]> git.kernelconcepts.de Git - karo-tx-linux.git/commitdiff
Merge branch 'for-3.3/mtip32xx' into for-3.3/drivers
authorJens Axboe <axboe@kernel.dk>
Sun, 15 Jan 2012 09:39:35 +0000 (10:39 +0100)
committerJens Axboe <axboe@kernel.dk>
Sun, 15 Jan 2012 09:39:35 +0000 (10:39 +0100)
drivers/block/Kconfig
drivers/block/Makefile
drivers/block/mtip32xx/Kconfig [new file with mode: 0644]
drivers/block/mtip32xx/Makefile [new file with mode: 0644]
drivers/block/mtip32xx/mtip32xx.c [new file with mode: 0644]
drivers/block/mtip32xx/mtip32xx.h [new file with mode: 0644]

index 6f07ec1c2f58d2dabd766463165e32728910faf6..a30aa103f95b33a4567b519250331725dc5f9539 100644 (file)
@@ -116,6 +116,8 @@ config PARIDE
 
 source "drivers/block/paride/Kconfig"
 
+source "drivers/block/mtip32xx/Kconfig"
+
 config BLK_CPQ_DA
        tristate "Compaq SMART2 support"
        depends on PCI && VIRT_TO_BUS
index 76646e9a1c91528617c22e2c3f429201531acdf4..ad7b74a44ef3dd3e1e1c39f7e44855e45e0bfd56 100644 (file)
@@ -39,5 +39,6 @@ obj-$(CONFIG_XEN_BLKDEV_FRONTEND)     += xen-blkfront.o
 obj-$(CONFIG_XEN_BLKDEV_BACKEND)       += xen-blkback/
 obj-$(CONFIG_BLK_DEV_DRBD)     += drbd/
 obj-$(CONFIG_BLK_DEV_RBD)     += rbd.o
+obj-$(CONFIG_BLK_DEV_PCIESSD_MTIP32XX) += mtip32xx/
 
 swim_mod-y     := swim.o swim_asm.o
diff --git a/drivers/block/mtip32xx/Kconfig b/drivers/block/mtip32xx/Kconfig
new file mode 100644 (file)
index 0000000..b5dd14e
--- /dev/null
@@ -0,0 +1,9 @@
+#
+# mtip32xx device driver configuration
+#
+
+config BLK_DEV_PCIESSD_MTIP32XX
+       tristate "Block Device Driver for Micron PCIe SSDs"
+       depends on HOTPLUG_PCI_PCIE
+       help
+          This enables the block driver for Micron PCIe SSDs.
diff --git a/drivers/block/mtip32xx/Makefile b/drivers/block/mtip32xx/Makefile
new file mode 100644 (file)
index 0000000..4fbef8c
--- /dev/null
@@ -0,0 +1,5 @@
+#
+# Makefile for  Block device driver for Micron PCIe SSD
+#
+
+obj-$(CONFIG_BLK_DEV_PCIESSD_MTIP32XX) += mtip32xx.o
diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
new file mode 100644 (file)
index 0000000..b74eab7
--- /dev/null
@@ -0,0 +1,3651 @@
+/*
+ * Driver for the Micron P320 SSD
+ *   Copyright (C) 2011 Micron Technology, Inc.
+ *
+ * Portions of this code were derived from works subjected to the
+ * following copyright:
+ *    Copyright (C) 2009 Integrated Device Technology, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/ata.h>
+#include <linux/delay.h>
+#include <linux/hdreg.h>
+#include <linux/uaccess.h>
+#include <linux/random.h>
+#include <linux/smp.h>
+#include <linux/compat.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/genhd.h>
+#include <linux/blkdev.h>
+#include <linux/bio.h>
+#include <linux/dma-mapping.h>
+#include <linux/idr.h>
+#include <linux/kthread.h>
+#include <../drivers/ata/ahci.h>
+#include "mtip32xx.h"
+
+#define HW_CMD_SLOT_SZ         (MTIP_MAX_COMMAND_SLOTS * 32)
+#define HW_CMD_TBL_SZ          (AHCI_CMD_TBL_HDR_SZ + (MTIP_MAX_SG * 16))
+#define HW_CMD_TBL_AR_SZ       (HW_CMD_TBL_SZ * MTIP_MAX_COMMAND_SLOTS)
+#define HW_PORT_PRIV_DMA_SZ \
+               (HW_CMD_SLOT_SZ + HW_CMD_TBL_AR_SZ + AHCI_RX_FIS_SZ)
+
+#define HOST_HSORG             0xFC
+#define HSORG_DISABLE_SLOTGRP_INTR (1<<24)
+#define HSORG_DISABLE_SLOTGRP_PXIS (1<<16)
+#define HSORG_HWREV            0xFF00
+#define HSORG_STYLE            0x8
+#define HSORG_SLOTGROUPS       0x7
+
+#define PORT_COMMAND_ISSUE     0x38
+#define PORT_SDBV              0x7C
+
+#define PORT_OFFSET            0x100
+#define PORT_MEM_SIZE          0x80
+
+#define PORT_IRQ_ERR \
+       (PORT_IRQ_HBUS_ERR | PORT_IRQ_IF_ERR | PORT_IRQ_CONNECT | \
+        PORT_IRQ_PHYRDY | PORT_IRQ_UNK_FIS | PORT_IRQ_BAD_PMP | \
+        PORT_IRQ_TF_ERR | PORT_IRQ_HBUS_DATA_ERR | PORT_IRQ_IF_NONFATAL | \
+        PORT_IRQ_OVERFLOW)
+#define PORT_IRQ_LEGACY \
+       (PORT_IRQ_PIOS_FIS | PORT_IRQ_D2H_REG_FIS)
+#define PORT_IRQ_HANDLED \
+       (PORT_IRQ_SDB_FIS | PORT_IRQ_LEGACY | \
+        PORT_IRQ_TF_ERR | PORT_IRQ_IF_ERR | \
+        PORT_IRQ_CONNECT | PORT_IRQ_PHYRDY)
+#define DEF_PORT_IRQ \
+       (PORT_IRQ_ERR | PORT_IRQ_LEGACY | PORT_IRQ_SDB_FIS)
+
+/* product numbers */
+#define MTIP_PRODUCT_UNKNOWN   0x00
+#define MTIP_PRODUCT_ASICFPGA  0x11
+
+/* Device instance number, incremented each time a device is probed. */
+static int instance;
+
+/*
+ * Global variable used to hold the major block device number
+ * allocated in mtip_init().
+ */
+static int mtip_major;
+
+static DEFINE_SPINLOCK(rssd_index_lock);
+static DEFINE_IDA(rssd_index_ida);
+
+static int mtip_block_initialize(struct driver_data *dd);
+
+#ifdef CONFIG_COMPAT
+struct mtip_compat_ide_task_request_s {
+       __u8            io_ports[8];
+       __u8            hob_ports[8];
+       ide_reg_valid_t out_flags;
+       ide_reg_valid_t in_flags;
+       int             data_phase;
+       int             req_cmd;
+       compat_ulong_t  out_size;
+       compat_ulong_t  in_size;
+};
+#endif
+
+/*
+ * This function check_for_surprise_removal is called
+ * while card is removed from the system and it will
+ * read the vendor id from the configration space
+ *
+ * @pdev Pointer to the pci_dev structure.
+ *
+ * return value
+ *      true if device removed, else false
+ */
+static bool mtip_check_surprise_removal(struct pci_dev *pdev)
+{
+       u16 vendor_id = 0;
+
+       /* Read the vendorID from the configuration space */
+       pci_read_config_word(pdev, 0x00, &vendor_id);
+       if (vendor_id == 0xFFFF)
+               return true; /* device removed */
+
+       return false; /* device present */
+}
+
+/*
+ * This function is called for clean the pending command in the
+ * command slot during the surprise removal of device and return
+ * error to the upper layer.
+ *
+ * @dd Pointer to the DRIVER_DATA structure.
+ *
+ * return value
+ *     None
+ */
+static void mtip_command_cleanup(struct driver_data *dd)
+{
+       int group = 0, commandslot = 0, commandindex = 0;
+       struct mtip_cmd *command;
+       struct mtip_port *port = dd->port;
+
+       for (group = 0; group < 4; group++) {
+               for (commandslot = 0; commandslot < 32; commandslot++) {
+                       if (!(port->allocated[group] & (1 << commandslot)))
+                               continue;
+
+                       commandindex = group << 5 | commandslot;
+                       command = &port->commands[commandindex];
+
+                       if (atomic_read(&command->active)
+                           && (command->async_callback)) {
+                               command->async_callback(command->async_data,
+                                       -ENODEV);
+                               command->async_callback = NULL;
+                               command->async_data = NULL;
+                       }
+
+                       dma_unmap_sg(&port->dd->pdev->dev,
+                               command->sg,
+                               command->scatter_ents,
+                               command->direction);
+               }
+       }
+
+       up(&port->cmd_slot);
+
+       atomic_set(&dd->drv_cleanup_done, true);
+}
+
+/*
+ * Obtain an empty command slot.
+ *
+ * This function needs to be reentrant since it could be called
+ * at the same time on multiple CPUs. The allocation of the
+ * command slot must be atomic.
+ *
+ * @port Pointer to the port data structure.
+ *
+ * return value
+ *     >= 0    Index of command slot obtained.
+ *     -1      No command slots available.
+ */
+static int get_slot(struct mtip_port *port)
+{
+       int slot, i;
+       unsigned int num_command_slots = port->dd->slot_groups * 32;
+
+       /*
+        * Try 10 times, because there is a small race here.
+        *  that's ok, because it's still cheaper than a lock.
+        *
+        * Race: Since this section is not protected by lock, same bit
+        * could be chosen by different process contexts running in
+        * different processor. So instead of costly lock, we are going
+        * with loop.
+        */
+       for (i = 0; i < 10; i++) {
+               slot = find_next_zero_bit(port->allocated,
+                                        num_command_slots, 1);
+               if ((slot < num_command_slots) &&
+                   (!test_and_set_bit(slot, port->allocated)))
+                       return slot;
+       }
+       dev_warn(&port->dd->pdev->dev, "Failed to get a tag.\n");
+
+       if (mtip_check_surprise_removal(port->dd->pdev)) {
+               /* Device not present, clean outstanding commands */
+               mtip_command_cleanup(port->dd);
+       }
+       return -1;
+}
+
+/*
+ * Release a command slot.
+ *
+ * @port Pointer to the port data structure.
+ * @tag  Tag of command to release
+ *
+ * return value
+ *     None
+ */
+static inline void release_slot(struct mtip_port *port, int tag)
+{
+       smp_mb__before_clear_bit();
+       clear_bit(tag, port->allocated);
+       smp_mb__after_clear_bit();
+}
+
+/*
+ * Reset the HBA (without sleeping)
+ *
+ * Just like hba_reset, except does not call sleep, so can be
+ * run from interrupt/tasklet context.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     0       The reset was successful.
+ *     -1      The HBA Reset bit did not clear.
+ */
+static int hba_reset_nosleep(struct driver_data *dd)
+{
+       unsigned long timeout;
+
+       /* Chip quirk: quiesce any chip function */
+       mdelay(10);
+
+       /* Set the reset bit */
+       writel(HOST_RESET, dd->mmio + HOST_CTL);
+
+       /* Flush */
+       readl(dd->mmio + HOST_CTL);
+
+       /*
+        * Wait 10ms then spin for up to 1 second
+        * waiting for reset acknowledgement
+        */
+       timeout = jiffies + msecs_to_jiffies(1000);
+       mdelay(10);
+       while ((readl(dd->mmio + HOST_CTL) & HOST_RESET)
+                && time_before(jiffies, timeout))
+               mdelay(1);
+
+       if (readl(dd->mmio + HOST_CTL) & HOST_RESET)
+               return -1;
+
+       return 0;
+}
+
+/*
+ * Issue a command to the hardware.
+ *
+ * Set the appropriate bit in the s_active and Command Issue hardware
+ * registers, causing hardware command processing to begin.
+ *
+ * @port Pointer to the port structure.
+ * @tag  The tag of the command to be issued.
+ *
+ * return value
+ *      None
+ */
+static inline void mtip_issue_ncq_command(struct mtip_port *port, int tag)
+{
+       unsigned long flags = 0;
+
+       atomic_set(&port->commands[tag].active, 1);
+
+       spin_lock_irqsave(&port->cmd_issue_lock, flags);
+
+       writel((1 << MTIP_TAG_BIT(tag)),
+                       port->s_active[MTIP_TAG_INDEX(tag)]);
+       writel((1 << MTIP_TAG_BIT(tag)),
+                       port->cmd_issue[MTIP_TAG_INDEX(tag)]);
+
+       spin_unlock_irqrestore(&port->cmd_issue_lock, flags);
+}
+
+/*
+ * Enable/disable the reception of FIS
+ *
+ * @port   Pointer to the port data structure
+ * @enable 1 to enable, 0 to disable
+ *
+ * return value
+ *     Previous state: 1 enabled, 0 disabled
+ */
+static int mtip_enable_fis(struct mtip_port *port, int enable)
+{
+       u32 tmp;
+
+       /* enable FIS reception */
+       tmp = readl(port->mmio + PORT_CMD);
+       if (enable)
+               writel(tmp | PORT_CMD_FIS_RX, port->mmio + PORT_CMD);
+       else
+               writel(tmp & ~PORT_CMD_FIS_RX, port->mmio + PORT_CMD);
+
+       /* Flush */
+       readl(port->mmio + PORT_CMD);
+
+       return (((tmp & PORT_CMD_FIS_RX) == PORT_CMD_FIS_RX));
+}
+
+/*
+ * Enable/disable the DMA engine
+ *
+ * @port   Pointer to the port data structure
+ * @enable 1 to enable, 0 to disable
+ *
+ * return value
+ *     Previous state: 1 enabled, 0 disabled.
+ */
+static int mtip_enable_engine(struct mtip_port *port, int enable)
+{
+       u32 tmp;
+
+       /* enable FIS reception */
+       tmp = readl(port->mmio + PORT_CMD);
+       if (enable)
+               writel(tmp | PORT_CMD_START, port->mmio + PORT_CMD);
+       else
+               writel(tmp & ~PORT_CMD_START, port->mmio + PORT_CMD);
+
+       readl(port->mmio + PORT_CMD);
+       return (((tmp & PORT_CMD_START) == PORT_CMD_START));
+}
+
+/*
+ * Enables the port DMA engine and FIS reception.
+ *
+ * return value
+ *     None
+ */
+static inline void mtip_start_port(struct mtip_port *port)
+{
+       /* Enable FIS reception */
+       mtip_enable_fis(port, 1);
+
+       /* Enable the DMA engine */
+       mtip_enable_engine(port, 1);
+}
+
+/*
+ * Deinitialize a port by disabling port interrupts, the DMA engine,
+ * and FIS reception.
+ *
+ * @port Pointer to the port structure
+ *
+ * return value
+ *     None
+ */
+static inline void mtip_deinit_port(struct mtip_port *port)
+{
+       /* Disable interrupts on this port */
+       writel(0, port->mmio + PORT_IRQ_MASK);
+
+       /* Disable the DMA engine */
+       mtip_enable_engine(port, 0);
+
+       /* Disable FIS reception */
+       mtip_enable_fis(port, 0);
+}
+
+/*
+ * Initialize a port.
+ *
+ * This function deinitializes the port by calling mtip_deinit_port() and
+ * then initializes it by setting the command header and RX FIS addresses,
+ * clearing the SError register and any pending port interrupts before
+ * re-enabling the default set of port interrupts.
+ *
+ * @port Pointer to the port structure.
+ *
+ * return value
+ *     None
+ */
+static void mtip_init_port(struct mtip_port *port)
+{
+       int i;
+       mtip_deinit_port(port);
+
+       /* Program the command list base and FIS base addresses */
+       if (readl(port->dd->mmio + HOST_CAP) & HOST_CAP_64) {
+               writel((port->command_list_dma >> 16) >> 16,
+                        port->mmio + PORT_LST_ADDR_HI);
+               writel((port->rxfis_dma >> 16) >> 16,
+                        port->mmio + PORT_FIS_ADDR_HI);
+       }
+
+       writel(port->command_list_dma & 0xFFFFFFFF,
+                       port->mmio + PORT_LST_ADDR);
+       writel(port->rxfis_dma & 0xFFFFFFFF, port->mmio + PORT_FIS_ADDR);
+
+       /* Clear SError */
+       writel(readl(port->mmio + PORT_SCR_ERR), port->mmio + PORT_SCR_ERR);
+
+       /* reset the completed registers.*/
+       for (i = 0; i < port->dd->slot_groups; i++)
+               writel(0xFFFFFFFF, port->completed[i]);
+
+       /* Clear any pending interrupts for this port */
+       writel(readl(port->mmio + PORT_IRQ_STAT), port->mmio + PORT_IRQ_STAT);
+
+       /* Enable port interrupts */
+       writel(DEF_PORT_IRQ, port->mmio + PORT_IRQ_MASK);
+}
+
+/*
+ * Restart a port
+ *
+ * @port Pointer to the port data structure.
+ *
+ * return value
+ *     None
+ */
+static void mtip_restart_port(struct mtip_port *port)
+{
+       unsigned long timeout;
+
+       /* Disable the DMA engine */
+       mtip_enable_engine(port, 0);
+
+       /* Chip quirk: wait up to 500ms for PxCMD.CR == 0 */
+       timeout = jiffies + msecs_to_jiffies(500);
+       while ((readl(port->mmio + PORT_CMD) & PORT_CMD_LIST_ON)
+                && time_before(jiffies, timeout))
+               ;
+
+       /*
+        * Chip quirk: escalate to hba reset if
+        * PxCMD.CR not clear after 500 ms
+        */
+       if (readl(port->mmio + PORT_CMD) & PORT_CMD_LIST_ON) {
+               dev_warn(&port->dd->pdev->dev,
+                       "PxCMD.CR not clear, escalating reset\n");
+
+               if (hba_reset_nosleep(port->dd))
+                       dev_err(&port->dd->pdev->dev,
+                               "HBA reset escalation failed.\n");
+
+               /* 30 ms delay before com reset to quiesce chip */
+               mdelay(30);
+       }
+
+       dev_warn(&port->dd->pdev->dev, "Issuing COM reset\n");
+
+       /* Set PxSCTL.DET */
+       writel(readl(port->mmio + PORT_SCR_CTL) |
+                        1, port->mmio + PORT_SCR_CTL);
+       readl(port->mmio + PORT_SCR_CTL);
+
+       /* Wait 1 ms to quiesce chip function */
+       timeout = jiffies + msecs_to_jiffies(1);
+       while (time_before(jiffies, timeout))
+               ;
+
+       /* Clear PxSCTL.DET */
+       writel(readl(port->mmio + PORT_SCR_CTL) & ~1,
+                        port->mmio + PORT_SCR_CTL);
+       readl(port->mmio + PORT_SCR_CTL);
+
+       /* Wait 500 ms for bit 0 of PORT_SCR_STS to be set */
+       timeout = jiffies + msecs_to_jiffies(500);
+       while (((readl(port->mmio + PORT_SCR_STAT) & 0x01) == 0)
+                        && time_before(jiffies, timeout))
+               ;
+
+       if ((readl(port->mmio + PORT_SCR_STAT) & 0x01) == 0)
+               dev_warn(&port->dd->pdev->dev,
+                       "COM reset failed\n");
+
+       /* Clear SError, the PxSERR.DIAG.x should be set so clear it */
+       writel(readl(port->mmio + PORT_SCR_ERR), port->mmio + PORT_SCR_ERR);
+
+       /* Enable the DMA engine */
+       mtip_enable_engine(port, 1);
+}
+
+/*
+ * Called periodically to see if any read/write commands are
+ * taking too long to complete.
+ *
+ * @data Pointer to the PORT data structure.
+ *
+ * return value
+ *     None
+ */
+static void mtip_timeout_function(unsigned long int data)
+{
+       struct mtip_port *port = (struct mtip_port *) data;
+       struct host_to_dev_fis *fis;
+       struct mtip_cmd *command;
+       int tag, cmdto_cnt = 0;
+       unsigned int bit, group;
+       unsigned int num_command_slots = port->dd->slot_groups * 32;
+
+       if (unlikely(!port))
+               return;
+
+       if (atomic_read(&port->dd->resumeflag) == true) {
+               mod_timer(&port->cmd_timer,
+                       jiffies + msecs_to_jiffies(30000));
+               return;
+       }
+
+       for (tag = 0; tag < num_command_slots; tag++) {
+               /*
+                * Skip internal command slot as it has
+                * its own timeout mechanism
+                */
+               if (tag == MTIP_TAG_INTERNAL)
+                       continue;
+
+               if (atomic_read(&port->commands[tag].active) &&
+                  (time_after(jiffies, port->commands[tag].comp_time))) {
+                       group = tag >> 5;
+                       bit = tag & 0x1F;
+
+                       command = &port->commands[tag];
+                       fis = (struct host_to_dev_fis *) command->command;
+
+                       dev_warn(&port->dd->pdev->dev,
+                               "Timeout for command tag %d\n", tag);
+
+                       cmdto_cnt++;
+                       if (cmdto_cnt == 1)
+                               set_bit(MTIP_FLAG_EH_ACTIVE_BIT, &port->flags);
+
+                       /*
+                        * Clear the completed bit. This should prevent
+                        *  any interrupt handlers from trying to retire
+                        *  the command.
+                        */
+                       writel(1 << bit, port->completed[group]);
+
+                       /* Call the async completion callback. */
+                       if (likely(command->async_callback))
+                               command->async_callback(command->async_data,
+                                                        -EIO);
+                       command->async_callback = NULL;
+                       command->comp_func = NULL;
+
+                       /* Unmap the DMA scatter list entries */
+                       dma_unmap_sg(&port->dd->pdev->dev,
+                                       command->sg,
+                                       command->scatter_ents,
+                                       command->direction);
+
+                       /*
+                        * Clear the allocated bit and active tag for the
+                        * command.
+                        */
+                       atomic_set(&port->commands[tag].active, 0);
+                       release_slot(port, tag);
+
+                       up(&port->cmd_slot);
+               }
+       }
+
+       if (cmdto_cnt) {
+               dev_warn(&port->dd->pdev->dev,
+                       "%d commands timed out: restarting port",
+                       cmdto_cnt);
+               mtip_restart_port(port);
+               clear_bit(MTIP_FLAG_EH_ACTIVE_BIT, &port->flags);
+               wake_up_interruptible(&port->svc_wait);
+       }
+
+       /* Restart the timer */
+       mod_timer(&port->cmd_timer,
+               jiffies + msecs_to_jiffies(MTIP_TIMEOUT_CHECK_PERIOD));
+}
+
+/*
+ * IO completion function.
+ *
+ * This completion function is called by the driver ISR when a
+ * command that was issued by the kernel completes. It first calls the
+ * asynchronous completion function which normally calls back into the block
+ * layer passing the asynchronous callback data, then unmaps the
+ * scatter list associated with the completed command, and finally
+ * clears the allocated bit associated with the completed command.
+ *
+ * @port   Pointer to the port data structure.
+ * @tag    Tag of the command.
+ * @data   Pointer to driver_data.
+ * @status Completion status.
+ *
+ * return value
+ *     None
+ */
+static void mtip_async_complete(struct mtip_port *port,
+                               int tag,
+                               void *data,
+                               int status)
+{
+       struct mtip_cmd *command;
+       struct driver_data *dd = data;
+       int cb_status = status ? -EIO : 0;
+
+       if (unlikely(!dd) || unlikely(!port))
+               return;
+
+       command = &port->commands[tag];
+
+       if (unlikely(status == PORT_IRQ_TF_ERR)) {
+               dev_warn(&port->dd->pdev->dev,
+                       "Command tag %d failed due to TFE\n", tag);
+       }
+
+       /* Upper layer callback */
+       if (likely(command->async_callback))
+               command->async_callback(command->async_data, cb_status);
+
+       command->async_callback = NULL;
+       command->comp_func = NULL;
+
+       /* Unmap the DMA scatter list entries */
+       dma_unmap_sg(&dd->pdev->dev,
+               command->sg,
+               command->scatter_ents,
+               command->direction);
+
+       /* Clear the allocated and active bits for the command */
+       atomic_set(&port->commands[tag].active, 0);
+       release_slot(port, tag);
+
+       up(&port->cmd_slot);
+}
+
+/*
+ * Internal command completion callback function.
+ *
+ * This function is normally called by the driver ISR when an internal
+ * command completed. This function signals the command completion by
+ * calling complete().
+ *
+ * @port   Pointer to the port data structure.
+ * @tag    Tag of the command that has completed.
+ * @data   Pointer to a completion structure.
+ * @status Completion status.
+ *
+ * return value
+ *     None
+ */
+static void mtip_completion(struct mtip_port *port,
+                           int tag,
+                           void *data,
+                           int status)
+{
+       struct mtip_cmd *command = &port->commands[tag];
+       struct completion *waiting = data;
+       if (unlikely(status == PORT_IRQ_TF_ERR))
+               dev_warn(&port->dd->pdev->dev,
+                       "Internal command %d completed with TFE\n", tag);
+
+       command->async_callback = NULL;
+       command->comp_func = NULL;
+
+       complete(waiting);
+}
+
+/*
+ * Helper function for tag logging
+ */
+static void print_tags(struct driver_data *dd,
+                       char *msg,
+                       unsigned long *tagbits)
+{
+       unsigned int tag, count = 0;
+
+       for (tag = 0; tag < (dd->slot_groups) * 32; tag++) {
+               if (test_bit(tag, tagbits))
+                       count++;
+       }
+       if (count)
+               dev_info(&dd->pdev->dev, "%s [%i tags]\n", msg, count);
+}
+
+/*
+ * Handle an error.
+ *
+ * @dd Pointer to the DRIVER_DATA structure.
+ *
+ * return value
+ *     None
+ */
+static void mtip_handle_tfe(struct driver_data *dd)
+{
+       int group, tag, bit, reissue;
+       struct mtip_port *port;
+       struct mtip_cmd  *command;
+       u32 completed;
+       struct host_to_dev_fis *fis;
+       unsigned long tagaccum[SLOTBITS_IN_LONGS];
+
+       dev_warn(&dd->pdev->dev, "Taskfile error\n");
+
+       port = dd->port;
+
+       /* Stop the timer to prevent command timeouts. */
+       del_timer(&port->cmd_timer);
+
+       /* Set eh_active */
+       set_bit(MTIP_FLAG_EH_ACTIVE_BIT, &port->flags);
+
+       /* Loop through all the groups */
+       for (group = 0; group < dd->slot_groups; group++) {
+               completed = readl(port->completed[group]);
+
+               /* clear completed status register in the hardware.*/
+               writel(completed, port->completed[group]);
+
+               /* clear the tag accumulator */
+               memset(tagaccum, 0, SLOTBITS_IN_LONGS * sizeof(long));
+
+               /* Process successfully completed commands */
+               for (bit = 0; bit < 32 && completed; bit++) {
+                       if (!(completed & (1<<bit)))
+                               continue;
+                       tag = (group << 5) + bit;
+
+                       /* Skip the internal command slot */
+                       if (tag == MTIP_TAG_INTERNAL)
+                               continue;
+
+                       command = &port->commands[tag];
+                       if (likely(command->comp_func)) {
+                               set_bit(tag, tagaccum);
+                               atomic_set(&port->commands[tag].active, 0);
+                               command->comp_func(port,
+                                        tag,
+                                        command->comp_data,
+                                        0);
+                       } else {
+                               dev_err(&port->dd->pdev->dev,
+                                       "Missing completion func for tag %d",
+                                       tag);
+                               if (mtip_check_surprise_removal(dd->pdev)) {
+                                       mtip_command_cleanup(dd);
+                                       /* don't proceed further */
+                                       return;
+                               }
+                       }
+               }
+       }
+       print_tags(dd, "TFE tags completed:", tagaccum);
+
+       /* Restart the port */
+       mdelay(20);
+       mtip_restart_port(port);
+
+       /* clear the tag accumulator */
+       memset(tagaccum, 0, SLOTBITS_IN_LONGS * sizeof(long));
+
+       /* Loop through all the groups */
+       for (group = 0; group < dd->slot_groups; group++) {
+               for (bit = 0; bit < 32; bit++) {
+                       reissue = 1;
+                       tag = (group << 5) + bit;
+
+                       /* If the active bit is set re-issue the command */
+                       if (atomic_read(&port->commands[tag].active) == 0)
+                               continue;
+
+                       fis = (struct host_to_dev_fis *)
+                               port->commands[tag].command;
+
+                       /* Should re-issue? */
+                       if (tag == MTIP_TAG_INTERNAL ||
+                           fis->command == ATA_CMD_SET_FEATURES)
+                               reissue = 0;
+
+                       /*
+                        * First check if this command has
+                        *  exceeded its retries.
+                        */
+                       if (reissue &&
+                           (port->commands[tag].retries-- > 0)) {
+
+                               set_bit(tag, tagaccum);
+
+                               /* Update the timeout value. */
+                               port->commands[tag].comp_time =
+                                       jiffies + msecs_to_jiffies(
+                                       MTIP_NCQ_COMMAND_TIMEOUT_MS);
+                               /* Re-issue the command. */
+                               mtip_issue_ncq_command(port, tag);
+
+                               continue;
+                       }
+
+                       /* Retire a command that will not be reissued */
+                       dev_warn(&port->dd->pdev->dev,
+                               "retiring tag %d\n", tag);
+                       atomic_set(&port->commands[tag].active, 0);
+
+                       if (port->commands[tag].comp_func)
+                               port->commands[tag].comp_func(
+                                       port,
+                                       tag,
+                                       port->commands[tag].comp_data,
+                                       PORT_IRQ_TF_ERR);
+                       else
+                               dev_warn(&port->dd->pdev->dev,
+                                       "Bad completion for tag %d\n",
+                                       tag);
+               }
+       }
+       print_tags(dd, "TFE tags reissued:", tagaccum);
+
+       /* clear eh_active */
+       clear_bit(MTIP_FLAG_EH_ACTIVE_BIT, &port->flags);
+       wake_up_interruptible(&port->svc_wait);
+
+       mod_timer(&port->cmd_timer,
+                jiffies + msecs_to_jiffies(MTIP_TIMEOUT_CHECK_PERIOD));
+}
+
+/*
+ * Handle a set device bits interrupt
+ */
+static inline void mtip_process_sdbf(struct driver_data *dd)
+{
+       struct mtip_port  *port = dd->port;
+       int group, tag, bit;
+       u32 completed;
+       struct mtip_cmd *command;
+
+       /* walk all bits in all slot groups */
+       for (group = 0; group < dd->slot_groups; group++) {
+               completed = readl(port->completed[group]);
+
+               /* clear completed status register in the hardware.*/
+               writel(completed, port->completed[group]);
+
+               /* Process completed commands. */
+               for (bit = 0;
+                    (bit < 32) && completed;
+                    bit++, completed >>= 1) {
+                       if (completed & 0x01) {
+                               tag = (group << 5) | bit;
+
+                               /* skip internal command slot. */
+                               if (unlikely(tag == MTIP_TAG_INTERNAL))
+                                       continue;
+
+                               command = &port->commands[tag];
+                               /* make internal callback */
+                               if (likely(command->comp_func)) {
+                                       command->comp_func(
+                                               port,
+                                               tag,
+                                               command->comp_data,
+                                               0);
+                               } else {
+                                       dev_warn(&dd->pdev->dev,
+                                               "Null completion "
+                                               "for tag %d",
+                                               tag);
+
+                                       if (mtip_check_surprise_removal(
+                                               dd->pdev)) {
+                                               mtip_command_cleanup(dd);
+                                               return;
+                                       }
+                               }
+                       }
+               }
+       }
+}
+
+/*
+ * Process legacy pio and d2h interrupts
+ */
+static inline void mtip_process_legacy(struct driver_data *dd, u32 port_stat)
+{
+       struct mtip_port *port = dd->port;
+       struct mtip_cmd *cmd = &port->commands[MTIP_TAG_INTERNAL];
+
+       if (test_bit(MTIP_FLAG_IC_ACTIVE_BIT, &port->flags) &&
+           (cmd != NULL) && !(readl(port->cmd_issue[MTIP_TAG_INTERNAL])
+               & (1 << MTIP_TAG_INTERNAL))) {
+               if (cmd->comp_func) {
+                       cmd->comp_func(port,
+                               MTIP_TAG_INTERNAL,
+                               cmd->comp_data,
+                               0);
+                       return;
+               }
+       }
+
+       dev_warn(&dd->pdev->dev, "IRQ status 0x%x ignored.\n", port_stat);
+
+       return;
+}
+
+/*
+ * Demux and handle errors
+ */
+static inline void mtip_process_errors(struct driver_data *dd, u32 port_stat)
+{
+       if (likely(port_stat & (PORT_IRQ_TF_ERR | PORT_IRQ_IF_ERR)))
+               mtip_handle_tfe(dd);
+
+       if (unlikely(port_stat & PORT_IRQ_CONNECT)) {
+               dev_warn(&dd->pdev->dev,
+                       "Clearing PxSERR.DIAG.x\n");
+               writel((1 << 26), dd->port->mmio + PORT_SCR_ERR);
+       }
+
+       if (unlikely(port_stat & PORT_IRQ_PHYRDY)) {
+               dev_warn(&dd->pdev->dev,
+                       "Clearing PxSERR.DIAG.n\n");
+               writel((1 << 16), dd->port->mmio + PORT_SCR_ERR);
+       }
+
+       if (unlikely(port_stat & ~PORT_IRQ_HANDLED)) {
+               dev_warn(&dd->pdev->dev,
+                       "Port stat errors %x unhandled\n",
+                       (port_stat & ~PORT_IRQ_HANDLED));
+       }
+}
+
+static inline irqreturn_t mtip_handle_irq(struct driver_data *data)
+{
+       struct driver_data *dd = (struct driver_data *) data;
+       struct mtip_port *port = dd->port;
+       u32 hba_stat, port_stat;
+       int rv = IRQ_NONE;
+
+       hba_stat = readl(dd->mmio + HOST_IRQ_STAT);
+       if (hba_stat) {
+               rv = IRQ_HANDLED;
+
+               /* Acknowledge the interrupt status on the port.*/
+               port_stat = readl(port->mmio + PORT_IRQ_STAT);
+               writel(port_stat, port->mmio + PORT_IRQ_STAT);
+
+               /* Demux port status */
+               if (likely(port_stat & PORT_IRQ_SDB_FIS))
+                       mtip_process_sdbf(dd);
+
+               if (unlikely(port_stat & PORT_IRQ_ERR)) {
+                       if (unlikely(mtip_check_surprise_removal(dd->pdev))) {
+                               mtip_command_cleanup(dd);
+                               /* don't proceed further */
+                               return IRQ_HANDLED;
+                       }
+
+                       mtip_process_errors(dd, port_stat & PORT_IRQ_ERR);
+               }
+
+               if (unlikely(port_stat & PORT_IRQ_LEGACY))
+                       mtip_process_legacy(dd, port_stat & PORT_IRQ_LEGACY);
+       }
+
+       /* acknowledge interrupt */
+       writel(hba_stat, dd->mmio + HOST_IRQ_STAT);
+
+       return rv;
+}
+
+/*
+ * Wrapper for mtip_handle_irq
+ * (ignores return code)
+ */
+static void mtip_tasklet(unsigned long data)
+{
+       mtip_handle_irq((struct driver_data *) data);
+}
+
+/*
+ * HBA interrupt subroutine.
+ *
+ * @irq                IRQ number.
+ * @instance   Pointer to the driver data structure.
+ *
+ * return value
+ *     IRQ_HANDLED     A HBA interrupt was pending and handled.
+ *     IRQ_NONE        This interrupt was not for the HBA.
+ */
+static irqreturn_t mtip_irq_handler(int irq, void *instance)
+{
+       struct driver_data *dd = instance;
+       tasklet_schedule(&dd->tasklet);
+       return IRQ_HANDLED;
+}
+
+static void mtip_issue_non_ncq_command(struct mtip_port *port, int tag)
+{
+       atomic_set(&port->commands[tag].active, 1);
+       writel(1 << MTIP_TAG_BIT(tag),
+               port->cmd_issue[MTIP_TAG_INDEX(tag)]);
+}
+
+/*
+ * Wait for port to quiesce
+ *
+ * @port    Pointer to port data structure
+ * @timeout Max duration to wait (ms)
+ *
+ * return value
+ *     0       Success
+ *     -EBUSY  Commands still active
+ */
+static int mtip_quiesce_io(struct mtip_port *port, unsigned long timeout)
+{
+       unsigned long to;
+       unsigned int n;
+       unsigned int active = 1;
+
+       to = jiffies + msecs_to_jiffies(timeout);
+       do {
+               if (test_bit(MTIP_FLAG_SVC_THD_ACTIVE_BIT, &port->flags) &&
+                       test_bit(MTIP_FLAG_ISSUE_CMDS_BIT, &port->flags)) {
+                       msleep(20);
+                       continue; /* svc thd is actively issuing commands */
+               }
+               /*
+                * Ignore s_active bit 0 of array element 0.
+                * This bit will always be set
+                */
+               active = readl(port->s_active[0]) & 0xFFFFFFFE;
+               for (n = 1; n < port->dd->slot_groups; n++)
+                       active |= readl(port->s_active[n]);
+
+               if (!active)
+                       break;
+
+               msleep(20);
+       } while (time_before(jiffies, to));
+
+       return active ? -EBUSY : 0;
+}
+
+/*
+ * Execute an internal command and wait for the completion.
+ *
+ * @port    Pointer to the port data structure.
+ * @fis     Pointer to the FIS that describes the command.
+ * @fis_len  Length in WORDS of the FIS.
+ * @buffer  DMA accessible for command data.
+ * @buf_len  Length, in bytes, of the data buffer.
+ * @opts    Command header options, excluding the FIS length
+ *             and the number of PRD entries.
+ * @timeout Time in ms to wait for the command to complete.
+ *
+ * return value
+ *     0        Command completed successfully.
+ *     -EFAULT  The buffer address is not correctly aligned.
+ *     -EBUSY   Internal command or other IO in progress.
+ *     -EAGAIN  Time out waiting for command to complete.
+ */
+static int mtip_exec_internal_command(struct mtip_port *port,
+                                       void *fis,
+                                       int fis_len,
+                                       dma_addr_t buffer,
+                                       int buf_len,
+                                       u32 opts,
+                                       gfp_t atomic,
+                                       unsigned long timeout)
+{
+       struct mtip_cmd_sg *command_sg;
+       DECLARE_COMPLETION_ONSTACK(wait);
+       int rv = 0;
+       struct mtip_cmd *int_cmd = &port->commands[MTIP_TAG_INTERNAL];
+
+       /* Make sure the buffer is 8 byte aligned. This is asic specific. */
+       if (buffer & 0x00000007) {
+               dev_err(&port->dd->pdev->dev,
+                       "SG buffer is not 8 byte aligned\n");
+               return -EFAULT;
+       }
+
+       /* Only one internal command should be running at a time */
+       if (test_and_set_bit(MTIP_TAG_INTERNAL, port->allocated)) {
+               dev_warn(&port->dd->pdev->dev,
+                       "Internal command already active\n");
+               return -EBUSY;
+       }
+       set_bit(MTIP_FLAG_IC_ACTIVE_BIT, &port->flags);
+
+       if (atomic == GFP_KERNEL) {
+               /* wait for io to complete if non atomic */
+               if (mtip_quiesce_io(port, 5000) < 0) {
+                       dev_warn(&port->dd->pdev->dev,
+                               "Failed to quiesce IO\n");
+                       release_slot(port, MTIP_TAG_INTERNAL);
+                       clear_bit(MTIP_FLAG_IC_ACTIVE_BIT, &port->flags);
+                       wake_up_interruptible(&port->svc_wait);
+                       return -EBUSY;
+               }
+
+               /* Set the completion function and data for the command. */
+               int_cmd->comp_data = &wait;
+               int_cmd->comp_func = mtip_completion;
+
+       } else {
+               /* Clear completion - we're going to poll */
+               int_cmd->comp_data = NULL;
+               int_cmd->comp_func = NULL;
+       }
+
+       /* Copy the command to the command table */
+       memcpy(int_cmd->command, fis, fis_len*4);
+
+       /* Populate the SG list */
+       int_cmd->command_header->opts =
+                __force_bit2int cpu_to_le32(opts | fis_len);
+       if (buf_len) {
+               command_sg = int_cmd->command + AHCI_CMD_TBL_HDR_SZ;
+
+               command_sg->info =
+                       __force_bit2int cpu_to_le32((buf_len-1) & 0x3FFFFF);
+               command_sg->dba =
+                       __force_bit2int cpu_to_le32(buffer & 0xFFFFFFFF);
+               command_sg->dba_upper =
+                       __force_bit2int cpu_to_le32((buffer >> 16) >> 16);
+
+               int_cmd->command_header->opts |=
+                       __force_bit2int cpu_to_le32((1 << 16));
+       }
+
+       /* Populate the command header */
+       int_cmd->command_header->byte_count = 0;
+
+       /* Issue the command to the hardware */
+       mtip_issue_non_ncq_command(port, MTIP_TAG_INTERNAL);
+
+       /* Poll if atomic, wait_for_completion otherwise */
+       if (atomic == GFP_KERNEL) {
+               /* Wait for the command to complete or timeout. */
+               if (wait_for_completion_timeout(
+                               &wait,
+                               msecs_to_jiffies(timeout)) == 0) {
+                       dev_err(&port->dd->pdev->dev,
+                               "Internal command did not complete [%d] "
+                               "within timeout of  %lu ms\n",
+                               atomic, timeout);
+                       rv = -EAGAIN;
+               }
+
+               if (readl(port->cmd_issue[MTIP_TAG_INTERNAL])
+                       & (1 << MTIP_TAG_INTERNAL)) {
+                       dev_warn(&port->dd->pdev->dev,
+                               "Retiring internal command but CI is 1.\n");
+               }
+
+       } else {
+               /* Spin for <timeout> checking if command still outstanding */
+               timeout = jiffies + msecs_to_jiffies(timeout);
+
+               while ((readl(
+                       port->cmd_issue[MTIP_TAG_INTERNAL])
+                       & (1 << MTIP_TAG_INTERNAL))
+                       && time_before(jiffies, timeout))
+                       ;
+
+               if (readl(port->cmd_issue[MTIP_TAG_INTERNAL])
+                       & (1 << MTIP_TAG_INTERNAL)) {
+                       dev_err(&port->dd->pdev->dev,
+                               "Internal command did not complete [%d]\n",
+                               atomic);
+                       rv = -EAGAIN;
+               }
+       }
+
+       /* Clear the allocated and active bits for the internal command. */
+       atomic_set(&int_cmd->active, 0);
+       release_slot(port, MTIP_TAG_INTERNAL);
+       clear_bit(MTIP_FLAG_IC_ACTIVE_BIT, &port->flags);
+       wake_up_interruptible(&port->svc_wait);
+
+       return rv;
+}
+
+/*
+ * Byte-swap ATA ID strings.
+ *
+ * ATA identify data contains strings in byte-swapped 16-bit words.
+ * They must be swapped (on all architectures) to be usable as C strings.
+ * This function swaps bytes in-place.
+ *
+ * @buf The buffer location of the string
+ * @len The number of bytes to swap
+ *
+ * return value
+ *     None
+ */
+static inline void ata_swap_string(u16 *buf, unsigned int len)
+{
+       int i;
+       for (i = 0; i < (len/2); i++)
+               be16_to_cpus(&buf[i]);
+}
+
+/*
+ * Request the device identity information.
+ *
+ * If a user space buffer is not specified, i.e. is NULL, the
+ * identify information is still read from the drive and placed
+ * into the identify data buffer (@e port->identify) in the
+ * port data structure.
+ * When the identify buffer contains valid identify information @e
+ * port->identify_valid is non-zero.
+ *
+ * @port        Pointer to the port structure.
+ * @user_buffer  A user space buffer where the identify data should be
+ *                    copied.
+ *
+ * return value
+ *     0       Command completed successfully.
+ *     -EFAULT An error occurred while coping data to the user buffer.
+ *     -1      Command failed.
+ */
+static int mtip_get_identify(struct mtip_port *port, void __user *user_buffer)
+{
+       int rv = 0;
+       struct host_to_dev_fis fis;
+
+       /* Build the FIS. */
+       memset(&fis, 0, sizeof(struct host_to_dev_fis));
+       fis.type        = 0x27;
+       fis.opts        = 1 << 7;
+       fis.command     = ATA_CMD_ID_ATA;
+
+       /* Set the identify information as invalid. */
+       port->identify_valid = 0;
+
+       /* Clear the identify information. */
+       memset(port->identify, 0, sizeof(u16) * ATA_ID_WORDS);
+
+       /* Execute the command. */
+       if (mtip_exec_internal_command(port,
+                               &fis,
+                               5,
+                               port->identify_dma,
+                               sizeof(u16) * ATA_ID_WORDS,
+                               0,
+                               GFP_KERNEL,
+                               MTIP_INTERNAL_COMMAND_TIMEOUT_MS)
+                               < 0) {
+               rv = -1;
+               goto out;
+       }
+
+       /*
+        * Perform any necessary byte-swapping.  Yes, the kernel does in fact
+        * perform field-sensitive swapping on the string fields.
+        * See the kernel use of ata_id_string() for proof of this.
+        */
+#ifdef __LITTLE_ENDIAN
+       ata_swap_string(port->identify + 27, 40);  /* model string*/
+       ata_swap_string(port->identify + 23, 8);   /* firmware string*/
+       ata_swap_string(port->identify + 10, 20);  /* serial# string*/
+#else
+       {
+               int i;
+               for (i = 0; i < ATA_ID_WORDS; i++)
+                       port->identify[i] = le16_to_cpu(port->identify[i]);
+       }
+#endif
+
+       /* Set the identify buffer as valid. */
+       port->identify_valid = 1;
+
+       if (user_buffer) {
+               if (copy_to_user(
+                       user_buffer,
+                       port->identify,
+                       ATA_ID_WORDS * sizeof(u16))) {
+                       rv = -EFAULT;
+                       goto out;
+               }
+       }
+
+out:
+       return rv;
+}
+
+/*
+ * Issue a standby immediate command to the device.
+ *
+ * @port Pointer to the port structure.
+ *
+ * return value
+ *     0       Command was executed successfully.
+ *     -1      An error occurred while executing the command.
+ */
+static int mtip_standby_immediate(struct mtip_port *port)
+{
+       int rv;
+       struct host_to_dev_fis  fis;
+
+       /* Build the FIS. */
+       memset(&fis, 0, sizeof(struct host_to_dev_fis));
+       fis.type        = 0x27;
+       fis.opts        = 1 << 7;
+       fis.command     = ATA_CMD_STANDBYNOW1;
+
+       /* Execute the command.  Use a 15-second timeout for large drives. */
+       rv = mtip_exec_internal_command(port,
+                                       &fis,
+                                       5,
+                                       0,
+                                       0,
+                                       0,
+                                       GFP_KERNEL,
+                                       15000);
+
+       return rv;
+}
+
+/*
+ * Get the drive capacity.
+ *
+ * @dd      Pointer to the device data structure.
+ * @sectors Pointer to the variable that will receive the sector count.
+ *
+ * return value
+ *     1 Capacity was returned successfully.
+ *     0 The identify information is invalid.
+ */
+static bool mtip_hw_get_capacity(struct driver_data *dd, sector_t *sectors)
+{
+       struct mtip_port *port = dd->port;
+       u64 total, raw0, raw1, raw2, raw3;
+       raw0 = port->identify[100];
+       raw1 = port->identify[101];
+       raw2 = port->identify[102];
+       raw3 = port->identify[103];
+       total = raw0 | raw1<<16 | raw2<<32 | raw3<<48;
+       *sectors = total;
+       return (bool) !!port->identify_valid;
+}
+
+/*
+ * Reset the HBA.
+ *
+ * Resets the HBA by setting the HBA Reset bit in the Global
+ * HBA Control register. After setting the HBA Reset bit the
+ * function waits for 1 second before reading the HBA Reset
+ * bit to make sure it has cleared. If HBA Reset is not clear
+ * an error is returned. Cannot be used in non-blockable
+ * context.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     0  The reset was successful.
+ *     -1 The HBA Reset bit did not clear.
+ */
+static int mtip_hba_reset(struct driver_data *dd)
+{
+       mtip_deinit_port(dd->port);
+
+       /* Set the reset bit */
+       writel(HOST_RESET, dd->mmio + HOST_CTL);
+
+       /* Flush */
+       readl(dd->mmio + HOST_CTL);
+
+       /* Wait for reset to clear */
+       ssleep(1);
+
+       /* Check the bit has cleared */
+       if (readl(dd->mmio + HOST_CTL) & HOST_RESET) {
+               dev_err(&dd->pdev->dev,
+                       "Reset bit did not clear.\n");
+               return -1;
+       }
+
+       return 0;
+}
+
+/*
+ * Display the identify command data.
+ *
+ * @port Pointer to the port data structure.
+ *
+ * return value
+ *     None
+ */
+static void mtip_dump_identify(struct mtip_port *port)
+{
+       sector_t sectors;
+       unsigned short revid;
+       char cbuf[42];
+
+       if (!port->identify_valid)
+               return;
+
+       strlcpy(cbuf, (char *)(port->identify+10), 21);
+       dev_info(&port->dd->pdev->dev,
+               "Serial No.: %s\n", cbuf);
+
+       strlcpy(cbuf, (char *)(port->identify+23), 9);
+       dev_info(&port->dd->pdev->dev,
+               "Firmware Ver.: %s\n", cbuf);
+
+       strlcpy(cbuf, (char *)(port->identify+27), 41);
+       dev_info(&port->dd->pdev->dev, "Model: %s\n", cbuf);
+
+       if (mtip_hw_get_capacity(port->dd, &sectors))
+               dev_info(&port->dd->pdev->dev,
+                       "Capacity: %llu sectors (%llu MB)\n",
+                        (u64)sectors,
+                        ((u64)sectors) * ATA_SECT_SIZE >> 20);
+
+       pci_read_config_word(port->dd->pdev, PCI_REVISION_ID, &revid);
+       switch (revid & 0xFF) {
+       case 0x1:
+               strlcpy(cbuf, "A0", 3);
+               break;
+       case 0x3:
+               strlcpy(cbuf, "A2", 3);
+               break;
+       default:
+               strlcpy(cbuf, "?", 2);
+               break;
+       }
+       dev_info(&port->dd->pdev->dev,
+               "Card Type: %s\n", cbuf);
+}
+
+/*
+ * Map the commands scatter list into the command table.
+ *
+ * @command Pointer to the command.
+ * @nents Number of scatter list entries.
+ *
+ * return value
+ *     None
+ */
+static inline void fill_command_sg(struct driver_data *dd,
+                               struct mtip_cmd *command,
+                               int nents)
+{
+       int n;
+       unsigned int dma_len;
+       struct mtip_cmd_sg *command_sg;
+       struct scatterlist *sg = command->sg;
+
+       command_sg = command->command + AHCI_CMD_TBL_HDR_SZ;
+
+       for (n = 0; n < nents; n++) {
+               dma_len = sg_dma_len(sg);
+               if (dma_len > 0x400000)
+                       dev_err(&dd->pdev->dev,
+                               "DMA segment length truncated\n");
+               command_sg->info = __force_bit2int
+                       cpu_to_le32((dma_len-1) & 0x3FFFFF);
+               command_sg->dba = __force_bit2int
+                       cpu_to_le32(sg_dma_address(sg));
+               command_sg->dba_upper = __force_bit2int
+                       cpu_to_le32((sg_dma_address(sg) >> 16) >> 16);
+               command_sg++;
+               sg++;
+       }
+}
+
+/*
+ * @brief Execute a drive command.
+ *
+ * return value 0 The command completed successfully.
+ * return value -1 An error occurred while executing the command.
+ */
+static int exec_drive_task(struct mtip_port *port, u8 *command)
+{
+       struct host_to_dev_fis  fis;
+       struct host_to_dev_fis *reply = (port->rxfis + RX_FIS_D2H_REG);
+
+       /* Build the FIS. */
+       memset(&fis, 0, sizeof(struct host_to_dev_fis));
+       fis.type        = 0x27;
+       fis.opts        = 1 << 7;
+       fis.command     = command[0];
+       fis.features    = command[1];
+       fis.sect_count  = command[2];
+       fis.sector      = command[3];
+       fis.cyl_low     = command[4];
+       fis.cyl_hi      = command[5];
+       fis.device      = command[6] & ~0x10; /* Clear the dev bit*/
+
+
+       dbg_printk(MTIP_DRV_NAME "%s: User Command: cmd %x, feat %x, "
+               "nsect %x, sect %x, lcyl %x, "
+               "hcyl %x, sel %x\n",
+               __func__,
+               command[0],
+               command[1],
+               command[2],
+               command[3],
+               command[4],
+               command[5],
+               command[6]);
+
+       /* Execute the command. */
+       if (mtip_exec_internal_command(port,
+                                &fis,
+                                5,
+                                0,
+                                0,
+                                0,
+                                GFP_KERNEL,
+                                MTIP_IOCTL_COMMAND_TIMEOUT_MS) < 0) {
+               return -1;
+       }
+
+       command[0] = reply->command; /* Status*/
+       command[1] = reply->features; /* Error*/
+       command[4] = reply->cyl_low;
+       command[5] = reply->cyl_hi;
+
+       dbg_printk(MTIP_DRV_NAME "%s: Completion Status: stat %x, "
+               "err %x , cyl_lo %x cyl_hi %x\n",
+               __func__,
+               command[0],
+               command[1],
+               command[4],
+               command[5]);
+
+       return 0;
+}
+
+/*
+ * @brief Execute a drive command.
+ *
+ * @param port Pointer to the port data structure.
+ * @param command Pointer to the user specified command parameters.
+ * @param user_buffer Pointer to the user space buffer where read sector
+ *                   data should be copied.
+ *
+ * return value 0 The command completed successfully.
+ * return value -EFAULT An error occurred while copying the completion
+ *                 data to the user space buffer.
+ * return value -1 An error occurred while executing the command.
+ */
+static int exec_drive_command(struct mtip_port *port, u8 *command,
+                               void __user *user_buffer)
+{
+       struct host_to_dev_fis  fis;
+       struct host_to_dev_fis *reply = (port->rxfis + RX_FIS_D2H_REG);
+
+       /* Build the FIS. */
+       memset(&fis, 0, sizeof(struct host_to_dev_fis));
+       fis.type                = 0x27;
+       fis.opts                = 1 << 7;
+       fis.command             = command[0];
+       fis.features    = command[2];
+       fis.sect_count  = command[3];
+       if (fis.command == ATA_CMD_SMART) {
+               fis.sector      = command[1];
+               fis.cyl_low     = 0x4F;
+               fis.cyl_hi      = 0xC2;
+       }
+
+       dbg_printk(MTIP_DRV_NAME
+               "%s: User Command: cmd %x, sect %x, "
+               "feat %x, sectcnt %x\n",
+               __func__,
+               command[0],
+               command[1],
+               command[2],
+               command[3]);
+
+       memset(port->sector_buffer, 0x00, ATA_SECT_SIZE);
+
+       /* Execute the command. */
+       if (mtip_exec_internal_command(port,
+                               &fis,
+                                5,
+                                port->sector_buffer_dma,
+                                (command[3] != 0) ? ATA_SECT_SIZE : 0,
+                                0,
+                                GFP_KERNEL,
+                                MTIP_IOCTL_COMMAND_TIMEOUT_MS)
+                                < 0) {
+               return -1;
+       }
+
+       /* Collect the completion status. */
+       command[0] = reply->command; /* Status*/
+       command[1] = reply->features; /* Error*/
+       command[2] = command[3];
+
+       dbg_printk(MTIP_DRV_NAME
+               "%s: Completion Status: stat %x, "
+               "err %x, cmd %x\n",
+               __func__,
+               command[0],
+               command[1],
+               command[2]);
+
+       if (user_buffer && command[3]) {
+               if (copy_to_user(user_buffer,
+                                port->sector_buffer,
+                                ATA_SECT_SIZE * command[3])) {
+                       return -EFAULT;
+               }
+       }
+
+       return 0;
+}
+
+/*
+ *  Indicates whether a command has a single sector payload.
+ *
+ *  @command passed to the device to perform the certain event.
+ *  @features passed to the device to perform the certain event.
+ *
+ *  return value
+ *     1       command is one that always has a single sector payload,
+ *             regardless of the value in the Sector Count field.
+ *      0       otherwise
+ *
+ */
+static unsigned int implicit_sector(unsigned char command,
+                                   unsigned char features)
+{
+       unsigned int rv = 0;
+
+       /* list of commands that have an implicit sector count of 1 */
+       switch (command) {
+       case ATA_CMD_SEC_SET_PASS:
+       case ATA_CMD_SEC_UNLOCK:
+       case ATA_CMD_SEC_ERASE_PREP:
+       case ATA_CMD_SEC_ERASE_UNIT:
+       case ATA_CMD_SEC_FREEZE_LOCK:
+       case ATA_CMD_SEC_DISABLE_PASS:
+       case ATA_CMD_PMP_READ:
+       case ATA_CMD_PMP_WRITE:
+               rv = 1;
+               break;
+       case ATA_CMD_SET_MAX:
+               if (features == ATA_SET_MAX_UNLOCK)
+                       rv = 1;
+               break;
+       case ATA_CMD_SMART:
+               if ((features == ATA_SMART_READ_VALUES) ||
+                               (features == ATA_SMART_READ_THRESHOLDS))
+                       rv = 1;
+               break;
+       case ATA_CMD_CONF_OVERLAY:
+               if ((features == ATA_DCO_IDENTIFY) ||
+                               (features == ATA_DCO_SET))
+                       rv = 1;
+               break;
+       }
+       return rv;
+}
+
+/*
+ * Executes a taskfile
+ * See ide_taskfile_ioctl() for derivation
+ */
+static int exec_drive_taskfile(struct driver_data *dd,
+                              void __user *buf,
+                              ide_task_request_t *req_task,
+                              int outtotal)
+{
+       struct host_to_dev_fis  fis;
+       struct host_to_dev_fis *reply;
+       u8 *outbuf = NULL;
+       u8 *inbuf = NULL;
+       dma_addr_t outbuf_dma = 0;
+       dma_addr_t inbuf_dma = 0;
+       dma_addr_t dma_buffer = 0;
+       int err = 0;
+       unsigned int taskin = 0;
+       unsigned int taskout = 0;
+       u8 nsect = 0;
+       unsigned int timeout = MTIP_IOCTL_COMMAND_TIMEOUT_MS;
+       unsigned int force_single_sector;
+       unsigned int transfer_size;
+       unsigned long task_file_data;
+       int intotal = outtotal + req_task->out_size;
+
+       taskout = req_task->out_size;
+       taskin = req_task->in_size;
+       /* 130560 = 512 * 0xFF*/
+       if (taskin > 130560 || taskout > 130560) {
+               err = -EINVAL;
+               goto abort;
+       }
+
+       if (taskout) {
+               outbuf = kzalloc(taskout, GFP_KERNEL);
+               if (outbuf == NULL) {
+                       err = -ENOMEM;
+                       goto abort;
+               }
+               if (copy_from_user(outbuf, buf + outtotal, taskout)) {
+                       err = -EFAULT;
+                       goto abort;
+               }
+               outbuf_dma = pci_map_single(dd->pdev,
+                                        outbuf,
+                                        taskout,
+                                        DMA_TO_DEVICE);
+               if (outbuf_dma == 0) {
+                       err = -ENOMEM;
+                       goto abort;
+               }
+               dma_buffer = outbuf_dma;
+       }
+
+       if (taskin) {
+               inbuf = kzalloc(taskin, GFP_KERNEL);
+               if (inbuf == NULL) {
+                       err = -ENOMEM;
+                       goto abort;
+               }
+
+               if (copy_from_user(inbuf, buf + intotal, taskin)) {
+                       err = -EFAULT;
+                       goto abort;
+               }
+               inbuf_dma = pci_map_single(dd->pdev,
+                                        inbuf,
+                                        taskin, DMA_FROM_DEVICE);
+               if (inbuf_dma == 0) {
+                       err = -ENOMEM;
+                       goto abort;
+               }
+               dma_buffer = inbuf_dma;
+       }
+
+       /* only supports PIO and non-data commands from this ioctl. */
+       switch (req_task->data_phase) {
+       case TASKFILE_OUT:
+               nsect = taskout / ATA_SECT_SIZE;
+               reply = (dd->port->rxfis + RX_FIS_PIO_SETUP);
+               break;
+       case TASKFILE_IN:
+               reply = (dd->port->rxfis + RX_FIS_PIO_SETUP);
+               break;
+       case TASKFILE_NO_DATA:
+               reply = (dd->port->rxfis + RX_FIS_D2H_REG);
+               break;
+       default:
+               err = -EINVAL;
+               goto abort;
+       }
+
+       /* Build the FIS. */
+       memset(&fis, 0, sizeof(struct host_to_dev_fis));
+
+       fis.type        = 0x27;
+       fis.opts        = 1 << 7;
+       fis.command     = req_task->io_ports[7];
+       fis.features    = req_task->io_ports[1];
+       fis.sect_count  = req_task->io_ports[2];
+       fis.lba_low     = req_task->io_ports[3];
+       fis.lba_mid     = req_task->io_ports[4];
+       fis.lba_hi      = req_task->io_ports[5];
+        /* Clear the dev bit*/
+       fis.device      = req_task->io_ports[6] & ~0x10;
+
+       if ((req_task->in_flags.all == 0) && (req_task->out_flags.all & 1)) {
+               req_task->in_flags.all  =
+                       IDE_TASKFILE_STD_IN_FLAGS |
+                       (IDE_HOB_STD_IN_FLAGS << 8);
+               fis.lba_low_ex          = req_task->hob_ports[3];
+               fis.lba_mid_ex          = req_task->hob_ports[4];
+               fis.lba_hi_ex           = req_task->hob_ports[5];
+               fis.features_ex         = req_task->hob_ports[1];
+               fis.sect_cnt_ex         = req_task->hob_ports[2];
+
+       } else {
+               req_task->in_flags.all = IDE_TASKFILE_STD_IN_FLAGS;
+       }
+
+       force_single_sector = implicit_sector(fis.command, fis.features);
+
+       if ((taskin || taskout) && (!fis.sect_count)) {
+               if (nsect)
+                       fis.sect_count = nsect;
+               else {
+                       if (!force_single_sector) {
+                               dev_warn(&dd->pdev->dev,
+                                       "data movement but "
+                                       "sect_count is 0\n");
+                                       err = -EINVAL;
+                                       goto abort;
+                       }
+               }
+       }
+
+       dbg_printk(MTIP_DRV_NAME
+               "taskfile: cmd %x, feat %x, nsect %x,"
+               " sect/lbal %x, lcyl/lbam %x, hcyl/lbah %x,"
+               " head/dev %x\n",
+               fis.command,
+               fis.features,
+               fis.sect_count,
+               fis.lba_low,
+               fis.lba_mid,
+               fis.lba_hi,
+               fis.device);
+
+       switch (fis.command) {
+       case ATA_CMD_DOWNLOAD_MICRO:
+               /* Change timeout for Download Microcode to 60 seconds.*/
+               timeout = 60000;
+               break;
+       case ATA_CMD_SEC_ERASE_UNIT:
+               /* Change timeout for Security Erase Unit to 4 minutes.*/
+               timeout = 240000;
+               break;
+       case ATA_CMD_STANDBYNOW1:
+               /* Change timeout for standby immediate to 10 seconds.*/
+               timeout = 10000;
+               break;
+       case 0xF7:
+       case 0xFA:
+               /* Change timeout for vendor unique command to 10 secs */
+               timeout = 10000;
+               break;
+       case ATA_CMD_SMART:
+               /* Change timeout for vendor unique command to 10 secs */
+               timeout = 10000;
+               break;
+       default:
+               timeout = MTIP_IOCTL_COMMAND_TIMEOUT_MS;
+               break;
+       }
+
+       /* Determine the correct transfer size.*/
+       if (force_single_sector)
+               transfer_size = ATA_SECT_SIZE;
+       else
+               transfer_size = ATA_SECT_SIZE * fis.sect_count;
+
+       /* Execute the command.*/
+       if (mtip_exec_internal_command(dd->port,
+                                &fis,
+                                5,
+                                dma_buffer,
+                                transfer_size,
+                                0,
+                                GFP_KERNEL,
+                                timeout) < 0) {
+               err = -EIO;
+               goto abort;
+       }
+
+       task_file_data = readl(dd->port->mmio+PORT_TFDATA);
+
+       if ((req_task->data_phase == TASKFILE_IN) && !(task_file_data & 1)) {
+               reply = dd->port->rxfis + RX_FIS_PIO_SETUP;
+               req_task->io_ports[7] = reply->control;
+       } else {
+               reply = dd->port->rxfis + RX_FIS_D2H_REG;
+               req_task->io_ports[7] = reply->command;
+       }
+
+       /* reclaim the DMA buffers.*/
+       if (inbuf_dma)
+               pci_unmap_single(dd->pdev, inbuf_dma,
+                       taskin, DMA_FROM_DEVICE);
+       if (outbuf_dma)
+               pci_unmap_single(dd->pdev, outbuf_dma,
+                       taskout, DMA_TO_DEVICE);
+       inbuf_dma  = 0;
+       outbuf_dma = 0;
+
+       /* return the ATA registers to the caller.*/
+       req_task->io_ports[1] = reply->features;
+       req_task->io_ports[2] = reply->sect_count;
+       req_task->io_ports[3] = reply->lba_low;
+       req_task->io_ports[4] = reply->lba_mid;
+       req_task->io_ports[5] = reply->lba_hi;
+       req_task->io_ports[6] = reply->device;
+
+       if (req_task->out_flags.all & 1)  {
+
+               req_task->hob_ports[3] = reply->lba_low_ex;
+               req_task->hob_ports[4] = reply->lba_mid_ex;
+               req_task->hob_ports[5] = reply->lba_hi_ex;
+               req_task->hob_ports[1] = reply->features_ex;
+               req_task->hob_ports[2] = reply->sect_cnt_ex;
+       }
+
+       /* Com rest after secure erase or lowlevel format */
+       if (((fis.command == ATA_CMD_SEC_ERASE_UNIT) ||
+               ((fis.command == 0xFC) &&
+                       (fis.features == 0x27 || fis.features == 0x72 ||
+                        fis.features == 0x62 || fis.features == 0x26))) &&
+                        !(reply->command & 1)) {
+               mtip_restart_port(dd->port);
+       }
+
+       dbg_printk(MTIP_DRV_NAME
+               "%s: Completion: stat %x,"
+               "err %x, sect_cnt %x, lbalo %x,"
+               "lbamid %x, lbahi %x, dev %x\n",
+               __func__,
+               req_task->io_ports[7],
+               req_task->io_ports[1],
+               req_task->io_ports[2],
+               req_task->io_ports[3],
+               req_task->io_ports[4],
+               req_task->io_ports[5],
+               req_task->io_ports[6]);
+
+       if (taskout) {
+               if (copy_to_user(buf + outtotal, outbuf, taskout)) {
+                       err = -EFAULT;
+                       goto abort;
+               }
+       }
+       if (taskin) {
+               if (copy_to_user(buf + intotal, inbuf, taskin)) {
+                       err = -EFAULT;
+                       goto abort;
+               }
+       }
+abort:
+       if (inbuf_dma)
+               pci_unmap_single(dd->pdev, inbuf_dma,
+                                       taskin, DMA_FROM_DEVICE);
+       if (outbuf_dma)
+               pci_unmap_single(dd->pdev, outbuf_dma,
+                                       taskout, DMA_TO_DEVICE);
+       kfree(outbuf);
+       kfree(inbuf);
+
+       return err;
+}
+
+/*
+ * Handle IOCTL calls from the Block Layer.
+ *
+ * This function is called by the Block Layer when it receives an IOCTL
+ * command that it does not understand. If the IOCTL command is not supported
+ * this function returns -ENOTTY.
+ *
+ * @dd  Pointer to the driver data structure.
+ * @cmd IOCTL command passed from the Block Layer.
+ * @arg IOCTL argument passed from the Block Layer.
+ *
+ * return value
+ *     0       The IOCTL completed successfully.
+ *     -ENOTTY The specified command is not supported.
+ *     -EFAULT An error occurred copying data to a user space buffer.
+ *     -EIO    An error occurred while executing the command.
+ */
+static int mtip_hw_ioctl(struct driver_data *dd, unsigned int cmd,
+                        unsigned long arg)
+{
+       switch (cmd) {
+       case HDIO_GET_IDENTITY:
+               if (mtip_get_identify(dd->port, (void __user *) arg) < 0) {
+                       dev_warn(&dd->pdev->dev,
+                               "Unable to read identity\n");
+                       return -EIO;
+               }
+
+               break;
+       case HDIO_DRIVE_CMD:
+       {
+               u8 drive_command[4];
+
+               /* Copy the user command info to our buffer. */
+               if (copy_from_user(drive_command,
+                                        (void __user *) arg,
+                                        sizeof(drive_command)))
+                       return -EFAULT;
+
+               /* Execute the drive command. */
+               if (exec_drive_command(dd->port,
+                                        drive_command,
+                                        (void __user *) (arg+4)))
+                       return -EIO;
+
+               /* Copy the status back to the users buffer. */
+               if (copy_to_user((void __user *) arg,
+                                        drive_command,
+                                        sizeof(drive_command)))
+                       return -EFAULT;
+
+               break;
+       }
+       case HDIO_DRIVE_TASK:
+       {
+               u8 drive_command[7];
+
+               /* Copy the user command info to our buffer. */
+               if (copy_from_user(drive_command,
+                                        (void __user *) arg,
+                                        sizeof(drive_command)))
+                       return -EFAULT;
+
+               /* Execute the drive command. */
+               if (exec_drive_task(dd->port, drive_command))
+                       return -EIO;
+
+               /* Copy the status back to the users buffer. */
+               if (copy_to_user((void __user *) arg,
+                                        drive_command,
+                                        sizeof(drive_command)))
+                       return -EFAULT;
+
+               break;
+       }
+       case HDIO_DRIVE_TASKFILE: {
+               ide_task_request_t req_task;
+               int ret, outtotal;
+
+               if (copy_from_user(&req_task, (void __user *) arg,
+                                       sizeof(req_task)))
+                       return -EFAULT;
+
+               outtotal = sizeof(req_task);
+
+               ret = exec_drive_taskfile(dd, (void __user *) arg,
+                                               &req_task, outtotal);
+
+               if (copy_to_user((void __user *) arg, &req_task,
+                                                       sizeof(req_task)))
+                       return -EFAULT;
+
+               return ret;
+       }
+
+       default:
+               return -EINVAL;
+       }
+       return 0;
+}
+
+/*
+ * Submit an IO to the hw
+ *
+ * This function is called by the block layer to issue an io
+ * to the device. Upon completion, the callback function will
+ * be called with the data parameter passed as the callback data.
+ *
+ * @dd       Pointer to the driver data structure.
+ * @start    First sector to read.
+ * @nsect    Number of sectors to read.
+ * @nents    Number of entries in scatter list for the read command.
+ * @tag      The tag of this read command.
+ * @callback Pointer to the function that should be called
+ *          when the read completes.
+ * @data     Callback data passed to the callback function
+ *          when the read completes.
+ * @barrier  If non-zero, this command must be completed before
+ *          issuing any other commands.
+ * @dir      Direction (read or write)
+ *
+ * return value
+ *     None
+ */
+static void mtip_hw_submit_io(struct driver_data *dd, sector_t start,
+                             int nsect, int nents, int tag, void *callback,
+                             void *data, int barrier, int dir)
+{
+       struct host_to_dev_fis  *fis;
+       struct mtip_port *port = dd->port;
+       struct mtip_cmd *command = &port->commands[tag];
+
+       /* Map the scatter list for DMA access */
+       if (dir == READ)
+               nents = dma_map_sg(&dd->pdev->dev, command->sg,
+                                       nents, DMA_FROM_DEVICE);
+       else
+               nents = dma_map_sg(&dd->pdev->dev, command->sg,
+                                       nents, DMA_TO_DEVICE);
+
+       command->scatter_ents = nents;
+
+       /*
+        * The number of retries for this command before it is
+        * reported as a failure to the upper layers.
+        */
+       command->retries = MTIP_MAX_RETRIES;
+
+       /* Fill out fis */
+       fis = command->command;
+       fis->type        = 0x27;
+       fis->opts        = 1 << 7;
+       fis->command     =
+               (dir == READ ? ATA_CMD_FPDMA_READ : ATA_CMD_FPDMA_WRITE);
+       *((unsigned int *) &fis->lba_low) = (start & 0xFFFFFF);
+       *((unsigned int *) &fis->lba_low_ex) = ((start >> 24) & 0xFFFFFF);
+       fis->device      = 1 << 6;
+       if (barrier)
+               fis->device |= FUA_BIT;
+       fis->features    = nsect & 0xFF;
+       fis->features_ex = (nsect >> 8) & 0xFF;
+       fis->sect_count  = ((tag << 3) | (tag >> 5));
+       fis->sect_cnt_ex = 0;
+       fis->control     = 0;
+       fis->res2        = 0;
+       fis->res3        = 0;
+       fill_command_sg(dd, command, nents);
+
+       /* Populate the command header */
+       command->command_header->opts =
+                       __force_bit2int cpu_to_le32(
+                               (nents << 16) | 5 | AHCI_CMD_PREFETCH);
+       command->command_header->byte_count = 0;
+
+       /*
+        * Set the completion function and data for the command
+        * within this layer.
+        */
+       command->comp_data = dd;
+       command->comp_func = mtip_async_complete;
+       command->direction = (dir == READ ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
+
+       /*
+        * Set the completion function and data for the command passed
+        * from the upper layer.
+        */
+       command->async_data = data;
+       command->async_callback = callback;
+
+       /*
+        * To prevent this command from being issued
+        * if an internal command is in progress or error handling is active.
+        */
+       if (unlikely(test_bit(MTIP_FLAG_IC_ACTIVE_BIT, &port->flags) ||
+                       test_bit(MTIP_FLAG_EH_ACTIVE_BIT, &port->flags))) {
+               set_bit(tag, port->cmds_to_issue);
+               set_bit(MTIP_FLAG_ISSUE_CMDS_BIT, &port->flags);
+               return;
+       }
+
+       /* Issue the command to the hardware */
+       mtip_issue_ncq_command(port, tag);
+
+       /* Set the command's timeout value.*/
+       port->commands[tag].comp_time = jiffies + msecs_to_jiffies(
+                                       MTIP_NCQ_COMMAND_TIMEOUT_MS);
+}
+
+/*
+ * Release a command slot.
+ *
+ * @dd  Pointer to the driver data structure.
+ * @tag Slot tag
+ *
+ * return value
+ *      None
+ */
+static void mtip_hw_release_scatterlist(struct driver_data *dd, int tag)
+{
+       release_slot(dd->port, tag);
+}
+
+/*
+ * Obtain a command slot and return its associated scatter list.
+ *
+ * @dd  Pointer to the driver data structure.
+ * @tag Pointer to an int that will receive the allocated command
+ *            slot tag.
+ *
+ * return value
+ *     Pointer to the scatter list for the allocated command slot
+ *     or NULL if no command slots are available.
+ */
+static struct scatterlist *mtip_hw_get_scatterlist(struct driver_data *dd,
+                                                  int *tag)
+{
+       /*
+        * It is possible that, even with this semaphore, a thread
+        * may think that no command slots are available. Therefore, we
+        * need to make an attempt to get_slot().
+        */
+       down(&dd->port->cmd_slot);
+       *tag = get_slot(dd->port);
+
+       if (unlikely(*tag < 0))
+               return NULL;
+
+       return dd->port->commands[*tag].sg;
+}
+
+/*
+ * Sysfs register/status dump.
+ *
+ * @dev  Pointer to the device structure, passed by the kernrel.
+ * @attr Pointer to the device_attribute structure passed by the kernel.
+ * @buf  Pointer to the char buffer that will receive the stats info.
+ *
+ * return value
+ *     The size, in bytes, of the data copied into buf.
+ */
+static ssize_t hw_show_registers(struct device *dev,
+                               struct device_attribute *attr,
+                               char *buf)
+{
+       u32 group_allocated;
+       struct driver_data *dd = dev_to_disk(dev)->private_data;
+       int size = 0;
+       int n;
+
+       size += sprintf(&buf[size], "%s:\ns_active:\n", __func__);
+
+       for (n = 0; n < dd->slot_groups; n++)
+               size += sprintf(&buf[size], "0x%08x\n",
+                                        readl(dd->port->s_active[n]));
+
+       size += sprintf(&buf[size], "Command Issue:\n");
+
+       for (n = 0; n < dd->slot_groups; n++)
+               size += sprintf(&buf[size], "0x%08x\n",
+                                       readl(dd->port->cmd_issue[n]));
+
+       size += sprintf(&buf[size], "Allocated:\n");
+
+       for (n = 0; n < dd->slot_groups; n++) {
+               if (sizeof(long) > sizeof(u32))
+                       group_allocated =
+                               dd->port->allocated[n/2] >> (32*(n&1));
+               else
+                       group_allocated = dd->port->allocated[n];
+               size += sprintf(&buf[size], "0x%08x\n",
+                                group_allocated);
+       }
+
+       size += sprintf(&buf[size], "completed:\n");
+
+       for (n = 0; n < dd->slot_groups; n++)
+               size += sprintf(&buf[size], "0x%08x\n",
+                               readl(dd->port->completed[n]));
+
+       size += sprintf(&buf[size], "PORT_IRQ_STAT 0x%08x\n",
+                               readl(dd->port->mmio + PORT_IRQ_STAT));
+       size += sprintf(&buf[size], "HOST_IRQ_STAT 0x%08x\n",
+                               readl(dd->mmio + HOST_IRQ_STAT));
+
+       return size;
+}
+static DEVICE_ATTR(registers, S_IRUGO, hw_show_registers, NULL);
+
+/*
+ * Create the sysfs related attributes.
+ *
+ * @dd   Pointer to the driver data structure.
+ * @kobj Pointer to the kobj for the block device.
+ *
+ * return value
+ *     0       Operation completed successfully.
+ *     -EINVAL Invalid parameter.
+ */
+static int mtip_hw_sysfs_init(struct driver_data *dd, struct kobject *kobj)
+{
+       if (!kobj || !dd)
+               return -EINVAL;
+
+       if (sysfs_create_file(kobj, &dev_attr_registers.attr))
+               dev_warn(&dd->pdev->dev,
+                       "Error creating registers sysfs entry\n");
+       return 0;
+}
+
+/*
+ * Remove the sysfs related attributes.
+ *
+ * @dd   Pointer to the driver data structure.
+ * @kobj Pointer to the kobj for the block device.
+ *
+ * return value
+ *     0       Operation completed successfully.
+ *     -EINVAL Invalid parameter.
+ */
+static int mtip_hw_sysfs_exit(struct driver_data *dd, struct kobject *kobj)
+{
+       if (!kobj || !dd)
+               return -EINVAL;
+
+       sysfs_remove_file(kobj, &dev_attr_registers.attr);
+
+       return 0;
+}
+
+/*
+ * Perform any init/resume time hardware setup
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     None
+ */
+static inline void hba_setup(struct driver_data *dd)
+{
+       u32 hwdata;
+       hwdata = readl(dd->mmio + HOST_HSORG);
+
+       /* interrupt bug workaround: use only 1 IS bit.*/
+       writel(hwdata |
+               HSORG_DISABLE_SLOTGRP_INTR |
+               HSORG_DISABLE_SLOTGRP_PXIS,
+               dd->mmio + HOST_HSORG);
+}
+
+/*
+ * Detect the details of the product, and store anything needed
+ * into the driver data structure.  This includes product type and
+ * version and number of slot groups.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     None
+ */
+static void mtip_detect_product(struct driver_data *dd)
+{
+       u32 hwdata;
+       unsigned int rev, slotgroups;
+
+       /*
+        * HBA base + 0xFC [15:0] - vendor-specific hardware interface
+        * info register:
+        * [15:8] hardware/software interface rev#
+        * [   3] asic-style interface
+        * [ 2:0] number of slot groups, minus 1 (only valid for asic-style).
+        */
+       hwdata = readl(dd->mmio + HOST_HSORG);
+
+       dd->product_type = MTIP_PRODUCT_UNKNOWN;
+       dd->slot_groups = 1;
+
+       if (hwdata & 0x8) {
+               dd->product_type = MTIP_PRODUCT_ASICFPGA;
+               rev = (hwdata & HSORG_HWREV) >> 8;
+               slotgroups = (hwdata & HSORG_SLOTGROUPS) + 1;
+               dev_info(&dd->pdev->dev,
+                       "ASIC-FPGA design, HS rev 0x%x, "
+                       "%i slot groups [%i slots]\n",
+                        rev,
+                        slotgroups,
+                        slotgroups * 32);
+
+               if (slotgroups > MTIP_MAX_SLOT_GROUPS) {
+                       dev_warn(&dd->pdev->dev,
+                               "Warning: driver only supports "
+                               "%i slot groups.\n", MTIP_MAX_SLOT_GROUPS);
+                       slotgroups = MTIP_MAX_SLOT_GROUPS;
+               }
+               dd->slot_groups = slotgroups;
+               return;
+       }
+
+       dev_warn(&dd->pdev->dev, "Unrecognized product id\n");
+}
+
+/*
+ * Blocking wait for FTL rebuild to complete
+ *
+ * @dd Pointer to the DRIVER_DATA structure.
+ *
+ * return value
+ *     0       FTL rebuild completed successfully
+ *     -EFAULT FTL rebuild error/timeout/interruption
+ */
+static int mtip_ftl_rebuild_poll(struct driver_data *dd)
+{
+       unsigned long timeout, cnt = 0, start;
+
+       dev_warn(&dd->pdev->dev,
+               "FTL rebuild in progress. Polling for completion.\n");
+
+       start = jiffies;
+       dd->ftlrebuildflag = 1;
+       timeout = jiffies + msecs_to_jiffies(MTIP_FTL_REBUILD_TIMEOUT_MS);
+
+       do {
+               if (mtip_check_surprise_removal(dd->pdev))
+                       return -EFAULT;
+
+               if (mtip_get_identify(dd->port, NULL) < 0)
+                       return -EFAULT;
+
+               if (*(dd->port->identify + MTIP_FTL_REBUILD_OFFSET) ==
+                       MTIP_FTL_REBUILD_MAGIC) {
+                       ssleep(1);
+                       /* Print message every 3 minutes */
+                       if (cnt++ >= 180) {
+                               dev_warn(&dd->pdev->dev,
+                               "FTL rebuild in progress (%d secs).\n",
+                               jiffies_to_msecs(jiffies - start) / 1000);
+                               cnt = 0;
+                       }
+               } else {
+                       dev_warn(&dd->pdev->dev,
+                               "FTL rebuild complete (%d secs).\n",
+                       jiffies_to_msecs(jiffies - start) / 1000);
+                       dd->ftlrebuildflag = 0;
+                       mtip_block_initialize(dd);
+                       break;
+               }
+               ssleep(10);
+       } while (time_before(jiffies, timeout));
+
+       /* Check for timeout */
+       if (dd->ftlrebuildflag) {
+               dev_err(&dd->pdev->dev,
+               "Timed out waiting for FTL rebuild to complete (%d secs).\n",
+               jiffies_to_msecs(jiffies - start) / 1000);
+               return -EFAULT;
+       }
+
+       return 0;
+}
+
+/*
+ * service thread to issue queued commands
+ *
+ * @data Pointer to the driver data structure.
+ *
+ * return value
+ *     0
+ */
+
+static int mtip_service_thread(void *data)
+{
+       struct driver_data *dd = (struct driver_data *)data;
+       unsigned long slot, slot_start, slot_wrap;
+       unsigned int num_cmd_slots = dd->slot_groups * 32;
+       struct mtip_port *port = dd->port;
+
+       while (1) {
+               /*
+                * the condition is to check neither an internal command is
+                * is in progress nor error handling is active
+                */
+               wait_event_interruptible(port->svc_wait, (port->flags) &&
+                       !test_bit(MTIP_FLAG_IC_ACTIVE_BIT, &port->flags) &&
+                       !test_bit(MTIP_FLAG_EH_ACTIVE_BIT, &port->flags));
+
+               if (kthread_should_stop())
+                       break;
+
+               set_bit(MTIP_FLAG_SVC_THD_ACTIVE_BIT, &port->flags);
+               if (test_bit(MTIP_FLAG_ISSUE_CMDS_BIT, &port->flags)) {
+                       slot = 1;
+                       /* used to restrict the loop to one iteration */
+                       slot_start = num_cmd_slots;
+                       slot_wrap = 0;
+                       while (1) {
+                               slot = find_next_bit(port->cmds_to_issue,
+                                               num_cmd_slots, slot);
+                               if (slot_wrap == 1) {
+                                       if ((slot_start >= slot) ||
+                                               (slot >= num_cmd_slots))
+                                               break;
+                               }
+                               if (unlikely(slot_start == num_cmd_slots))
+                                       slot_start = slot;
+
+                               if (unlikely(slot == num_cmd_slots)) {
+                                       slot = 1;
+                                       slot_wrap = 1;
+                                       continue;
+                               }
+
+                               /* Issue the command to the hardware */
+                               mtip_issue_ncq_command(port, slot);
+
+                               /* Set the command's timeout value.*/
+                               port->commands[slot].comp_time = jiffies +
+                               msecs_to_jiffies(MTIP_NCQ_COMMAND_TIMEOUT_MS);
+
+                               clear_bit(slot, port->cmds_to_issue);
+                       }
+
+                       clear_bit(MTIP_FLAG_ISSUE_CMDS_BIT, &port->flags);
+               } else if (test_bit(MTIP_FLAG_REBUILD_BIT, &port->flags)) {
+                       mtip_ftl_rebuild_poll(dd);
+                       clear_bit(MTIP_FLAG_REBUILD_BIT, &port->flags);
+               }
+               clear_bit(MTIP_FLAG_SVC_THD_ACTIVE_BIT, &port->flags);
+
+               if (test_bit(MTIP_FLAG_SVC_THD_SHOULD_STOP_BIT, &port->flags))
+                       break;
+       }
+       return 0;
+}
+
+/*
+ * Called once for each card.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     0 on success, else an error code.
+ */
+static int mtip_hw_init(struct driver_data *dd)
+{
+       int i;
+       int rv;
+       unsigned int num_command_slots;
+
+       dd->mmio = pcim_iomap_table(dd->pdev)[MTIP_ABAR];
+
+       mtip_detect_product(dd);
+       if (dd->product_type == MTIP_PRODUCT_UNKNOWN) {
+               rv = -EIO;
+               goto out1;
+       }
+       num_command_slots = dd->slot_groups * 32;
+
+       hba_setup(dd);
+
+       tasklet_init(&dd->tasklet, mtip_tasklet, (unsigned long)dd);
+
+       dd->port = kzalloc(sizeof(struct mtip_port), GFP_KERNEL);
+       if (!dd->port) {
+               dev_err(&dd->pdev->dev,
+                       "Memory allocation: port structure\n");
+               return -ENOMEM;
+       }
+
+       /* Counting semaphore to track command slot usage */
+       sema_init(&dd->port->cmd_slot, num_command_slots - 1);
+
+       /* Spinlock to prevent concurrent issue */
+       spin_lock_init(&dd->port->cmd_issue_lock);
+
+       /* Set the port mmio base address. */
+       dd->port->mmio  = dd->mmio + PORT_OFFSET;
+       dd->port->dd    = dd;
+
+       /* Allocate memory for the command list. */
+       dd->port->command_list =
+               dmam_alloc_coherent(&dd->pdev->dev,
+                       HW_PORT_PRIV_DMA_SZ + (ATA_SECT_SIZE * 2),
+                       &dd->port->command_list_dma,
+                       GFP_KERNEL);
+       if (!dd->port->command_list) {
+               dev_err(&dd->pdev->dev,
+                       "Memory allocation: command list\n");
+               rv = -ENOMEM;
+               goto out1;
+       }
+
+       /* Clear the memory we have allocated. */
+       memset(dd->port->command_list,
+               0,
+               HW_PORT_PRIV_DMA_SZ + (ATA_SECT_SIZE * 2));
+
+       /* Setup the addresse of the RX FIS. */
+       dd->port->rxfis     = dd->port->command_list + HW_CMD_SLOT_SZ;
+       dd->port->rxfis_dma = dd->port->command_list_dma + HW_CMD_SLOT_SZ;
+
+       /* Setup the address of the command tables. */
+       dd->port->command_table   = dd->port->rxfis + AHCI_RX_FIS_SZ;
+       dd->port->command_tbl_dma = dd->port->rxfis_dma + AHCI_RX_FIS_SZ;
+
+       /* Setup the address of the identify data. */
+       dd->port->identify     = dd->port->command_table +
+                                       HW_CMD_TBL_AR_SZ;
+       dd->port->identify_dma = dd->port->command_tbl_dma +
+                                       HW_CMD_TBL_AR_SZ;
+
+       /* Setup the address of the sector buffer. */
+       dd->port->sector_buffer = (void *) dd->port->identify + ATA_SECT_SIZE;
+       dd->port->sector_buffer_dma = dd->port->identify_dma + ATA_SECT_SIZE;
+
+       /* Point the command headers at the command tables. */
+       for (i = 0; i < num_command_slots; i++) {
+               dd->port->commands[i].command_header =
+                                       dd->port->command_list +
+                                       (sizeof(struct mtip_cmd_hdr) * i);
+               dd->port->commands[i].command_header_dma =
+                                       dd->port->command_list_dma +
+                                       (sizeof(struct mtip_cmd_hdr) * i);
+
+               dd->port->commands[i].command =
+                       dd->port->command_table + (HW_CMD_TBL_SZ * i);
+               dd->port->commands[i].command_dma =
+                       dd->port->command_tbl_dma + (HW_CMD_TBL_SZ * i);
+
+               if (readl(dd->mmio + HOST_CAP) & HOST_CAP_64)
+                       dd->port->commands[i].command_header->ctbau =
+                       __force_bit2int cpu_to_le32(
+                       (dd->port->commands[i].command_dma >> 16) >> 16);
+               dd->port->commands[i].command_header->ctba =
+                       __force_bit2int cpu_to_le32(
+                       dd->port->commands[i].command_dma & 0xFFFFFFFF);
+
+               /*
+                * If this is not done, a bug is reported by the stock
+                * FC11 i386. Due to the fact that it has lots of kernel
+                * debugging enabled.
+                */
+               sg_init_table(dd->port->commands[i].sg, MTIP_MAX_SG);
+
+               /* Mark all commands as currently inactive.*/
+               atomic_set(&dd->port->commands[i].active, 0);
+       }
+
+       /* Setup the pointers to the extended s_active and CI registers. */
+       for (i = 0; i < dd->slot_groups; i++) {
+               dd->port->s_active[i] =
+                       dd->port->mmio + i*0x80 + PORT_SCR_ACT;
+               dd->port->cmd_issue[i] =
+                       dd->port->mmio + i*0x80 + PORT_COMMAND_ISSUE;
+               dd->port->completed[i] =
+                       dd->port->mmio + i*0x80 + PORT_SDBV;
+       }
+
+       /* Reset the HBA. */
+       if (mtip_hba_reset(dd) < 0) {
+               dev_err(&dd->pdev->dev,
+                       "Card did not reset within timeout\n");
+               rv = -EIO;
+               goto out2;
+       }
+
+       mtip_init_port(dd->port);
+       mtip_start_port(dd->port);
+
+       /* Setup the ISR and enable interrupts. */
+       rv = devm_request_irq(&dd->pdev->dev,
+                               dd->pdev->irq,
+                               mtip_irq_handler,
+                               IRQF_SHARED,
+                               dev_driver_string(&dd->pdev->dev),
+                               dd);
+
+       if (rv) {
+               dev_err(&dd->pdev->dev,
+                       "Unable to allocate IRQ %d\n", dd->pdev->irq);
+               goto out2;
+       }
+
+       /* Enable interrupts on the HBA. */
+       writel(readl(dd->mmio + HOST_CTL) | HOST_IRQ_EN,
+                                       dd->mmio + HOST_CTL);
+
+       init_timer(&dd->port->cmd_timer);
+       init_waitqueue_head(&dd->port->svc_wait);
+
+       dd->port->cmd_timer.data = (unsigned long int) dd->port;
+       dd->port->cmd_timer.function = mtip_timeout_function;
+       mod_timer(&dd->port->cmd_timer,
+               jiffies + msecs_to_jiffies(MTIP_TIMEOUT_CHECK_PERIOD));
+
+       if (mtip_get_identify(dd->port, NULL) < 0) {
+               rv = -EFAULT;
+               goto out3;
+       }
+
+       if (*(dd->port->identify + MTIP_FTL_REBUILD_OFFSET) ==
+               MTIP_FTL_REBUILD_MAGIC) {
+               set_bit(MTIP_FLAG_REBUILD_BIT, &dd->port->flags);
+               return MTIP_FTL_REBUILD_MAGIC;
+       }
+       mtip_dump_identify(dd->port);
+       return rv;
+
+out3:
+       del_timer_sync(&dd->port->cmd_timer);
+
+       /* Disable interrupts on the HBA. */
+       writel(readl(dd->mmio + HOST_CTL) & ~HOST_IRQ_EN,
+                       dd->mmio + HOST_CTL);
+
+       /*Release the IRQ. */
+       devm_free_irq(&dd->pdev->dev, dd->pdev->irq, dd);
+
+out2:
+       mtip_deinit_port(dd->port);
+
+       /* Free the command/command header memory. */
+       dmam_free_coherent(&dd->pdev->dev,
+                               HW_PORT_PRIV_DMA_SZ + (ATA_SECT_SIZE * 2),
+                               dd->port->command_list,
+                               dd->port->command_list_dma);
+out1:
+       /* Free the memory allocated for the for structure. */
+       kfree(dd->port);
+
+       return rv;
+}
+
+/*
+ * Called to deinitialize an interface.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     0
+ */
+static int mtip_hw_exit(struct driver_data *dd)
+{
+       /*
+        * Send standby immediate (E0h) to the drive so that it
+        * saves its state.
+        */
+       if (atomic_read(&dd->drv_cleanup_done) != true) {
+
+               mtip_standby_immediate(dd->port);
+
+               /* de-initialize the port. */
+               mtip_deinit_port(dd->port);
+
+               /* Disable interrupts on the HBA. */
+               writel(readl(dd->mmio + HOST_CTL) & ~HOST_IRQ_EN,
+                               dd->mmio + HOST_CTL);
+       }
+
+       del_timer_sync(&dd->port->cmd_timer);
+
+       /* Release the IRQ. */
+       devm_free_irq(&dd->pdev->dev, dd->pdev->irq, dd);
+
+       /* Stop the bottom half tasklet. */
+       tasklet_kill(&dd->tasklet);
+
+       /* Free the command/command header memory. */
+       dmam_free_coherent(&dd->pdev->dev,
+                       HW_PORT_PRIV_DMA_SZ + (ATA_SECT_SIZE * 2),
+                       dd->port->command_list,
+                       dd->port->command_list_dma);
+       /* Free the memory allocated for the for structure. */
+       kfree(dd->port);
+
+       return 0;
+}
+
+/*
+ * Issue a Standby Immediate command to the device.
+ *
+ * This function is called by the Block Layer just before the
+ * system powers off during a shutdown.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     0
+ */
+static int mtip_hw_shutdown(struct driver_data *dd)
+{
+       /*
+        * Send standby immediate (E0h) to the drive so that it
+        * saves its state.
+        */
+       mtip_standby_immediate(dd->port);
+
+       return 0;
+}
+
+/*
+ * Suspend function
+ *
+ * This function is called by the Block Layer just before the
+ * system hibernates.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     0       Suspend was successful
+ *     -EFAULT Suspend was not successful
+ */
+static int mtip_hw_suspend(struct driver_data *dd)
+{
+       /*
+        * Send standby immediate (E0h) to the drive
+        * so that it saves its state.
+        */
+       if (mtip_standby_immediate(dd->port) != 0) {
+               dev_err(&dd->pdev->dev,
+                       "Failed standby-immediate command\n");
+               return -EFAULT;
+       }
+
+       /* Disable interrupts on the HBA.*/
+       writel(readl(dd->mmio + HOST_CTL) & ~HOST_IRQ_EN,
+                       dd->mmio + HOST_CTL);
+       mtip_deinit_port(dd->port);
+
+       return 0;
+}
+
+/*
+ * Resume function
+ *
+ * This function is called by the Block Layer as the
+ * system resumes.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     0       Resume was successful
+ *      -EFAULT Resume was not successful
+ */
+static int mtip_hw_resume(struct driver_data *dd)
+{
+       /* Perform any needed hardware setup steps */
+       hba_setup(dd);
+
+       /* Reset the HBA */
+       if (mtip_hba_reset(dd) != 0) {
+               dev_err(&dd->pdev->dev,
+                       "Unable to reset the HBA\n");
+               return -EFAULT;
+       }
+
+       /*
+        * Enable the port, DMA engine, and FIS reception specific
+        * h/w in controller.
+        */
+       mtip_init_port(dd->port);
+       mtip_start_port(dd->port);
+
+       /* Enable interrupts on the HBA.*/
+       writel(readl(dd->mmio + HOST_CTL) | HOST_IRQ_EN,
+                       dd->mmio + HOST_CTL);
+
+       return 0;
+}
+
+/*
+ * Helper function for reusing disk name
+ * upon hot insertion.
+ */
+static int rssd_disk_name_format(char *prefix,
+                                int index,
+                                char *buf,
+                                int buflen)
+{
+       const int base = 'z' - 'a' + 1;
+       char *begin = buf + strlen(prefix);
+       char *end = buf + buflen;
+       char *p;
+       int unit;
+
+       p = end - 1;
+       *p = '\0';
+       unit = base;
+       do {
+               if (p == begin)
+                       return -EINVAL;
+               *--p = 'a' + (index % unit);
+               index = (index / unit) - 1;
+       } while (index >= 0);
+
+       memmove(begin, p, end - p);
+       memcpy(buf, prefix, strlen(prefix));
+
+       return 0;
+}
+
+/*
+ * Block layer IOCTL handler.
+ *
+ * @dev Pointer to the block_device structure.
+ * @mode ignored
+ * @cmd IOCTL command passed from the user application.
+ * @arg Argument passed from the user application.
+ *
+ * return value
+ *     0        IOCTL completed successfully.
+ *     -ENOTTY  IOCTL not supported or invalid driver data
+ *                 structure pointer.
+ */
+static int mtip_block_ioctl(struct block_device *dev,
+                           fmode_t mode,
+                           unsigned cmd,
+                           unsigned long arg)
+{
+       struct driver_data *dd = dev->bd_disk->private_data;
+
+       if (!capable(CAP_SYS_ADMIN))
+               return -EACCES;
+
+       if (!dd)
+               return -ENOTTY;
+
+       switch (cmd) {
+       case BLKFLSBUF:
+               return -ENOTTY;
+       default:
+               return mtip_hw_ioctl(dd, cmd, arg);
+       }
+}
+
+#ifdef CONFIG_COMPAT
+/*
+ * Block layer compat IOCTL handler.
+ *
+ * @dev Pointer to the block_device structure.
+ * @mode ignored
+ * @cmd IOCTL command passed from the user application.
+ * @arg Argument passed from the user application.
+ *
+ * return value
+ *     0        IOCTL completed successfully.
+ *     -ENOTTY  IOCTL not supported or invalid driver data
+ *                 structure pointer.
+ */
+static int mtip_block_compat_ioctl(struct block_device *dev,
+                           fmode_t mode,
+                           unsigned cmd,
+                           unsigned long arg)
+{
+       struct driver_data *dd = dev->bd_disk->private_data;
+
+       if (!capable(CAP_SYS_ADMIN))
+               return -EACCES;
+
+       if (!dd)
+               return -ENOTTY;
+
+       switch (cmd) {
+       case BLKFLSBUF:
+               return -ENOTTY;
+       case HDIO_DRIVE_TASKFILE: {
+               struct mtip_compat_ide_task_request_s __user *compat_req_task;
+               ide_task_request_t req_task;
+               int compat_tasksize, outtotal, ret;
+
+               compat_tasksize =
+                       sizeof(struct mtip_compat_ide_task_request_s);
+
+               compat_req_task =
+                       (struct mtip_compat_ide_task_request_s __user *) arg;
+
+               if (copy_from_user(&req_task, (void __user *) arg,
+                       compat_tasksize - (2 * sizeof(compat_long_t))))
+                       return -EFAULT;
+
+               if (get_user(req_task.out_size, &compat_req_task->out_size))
+                       return -EFAULT;
+
+               if (get_user(req_task.in_size, &compat_req_task->in_size))
+                       return -EFAULT;
+
+               outtotal = sizeof(struct mtip_compat_ide_task_request_s);
+
+               ret = exec_drive_taskfile(dd, (void __user *) arg,
+                                               &req_task, outtotal);
+
+               if (copy_to_user((void __user *) arg, &req_task,
+                               compat_tasksize -
+                               (2 * sizeof(compat_long_t))))
+                       return -EFAULT;
+
+               if (put_user(req_task.out_size, &compat_req_task->out_size))
+                       return -EFAULT;
+
+               if (put_user(req_task.in_size, &compat_req_task->in_size))
+                       return -EFAULT;
+
+               return ret;
+       }
+       default:
+               return mtip_hw_ioctl(dd, cmd, arg);
+       }
+}
+#endif
+
+/*
+ * Obtain the geometry of the device.
+ *
+ * You may think that this function is obsolete, but some applications,
+ * fdisk for example still used CHS values. This function describes the
+ * device as having 224 heads and 56 sectors per cylinder. These values are
+ * chosen so that each cylinder is aligned on a 4KB boundary. Since a
+ * partition is described in terms of a start and end cylinder this means
+ * that each partition is also 4KB aligned. Non-aligned partitions adversely
+ * affects performance.
+ *
+ * @dev Pointer to the block_device strucutre.
+ * @geo Pointer to a hd_geometry structure.
+ *
+ * return value
+ *     0       Operation completed successfully.
+ *     -ENOTTY An error occurred while reading the drive capacity.
+ */
+static int mtip_block_getgeo(struct block_device *dev,
+                               struct hd_geometry *geo)
+{
+       struct driver_data *dd = dev->bd_disk->private_data;
+       sector_t capacity;
+
+       if (!dd)
+               return -ENOTTY;
+
+       if (!(mtip_hw_get_capacity(dd, &capacity))) {
+               dev_warn(&dd->pdev->dev,
+                       "Could not get drive capacity.\n");
+               return -ENOTTY;
+       }
+
+       geo->heads = 224;
+       geo->sectors = 56;
+       sector_div(capacity, (geo->heads * geo->sectors));
+       geo->cylinders = capacity;
+       return 0;
+}
+
+/*
+ * Block device operation function.
+ *
+ * This structure contains pointers to the functions required by the block
+ * layer.
+ */
+static const struct block_device_operations mtip_block_ops = {
+       .ioctl          = mtip_block_ioctl,
+#ifdef CONFIG_COMPAT
+       .compat_ioctl   = mtip_block_compat_ioctl,
+#endif
+       .getgeo         = mtip_block_getgeo,
+       .owner          = THIS_MODULE
+};
+
+/*
+ * Block layer make request function.
+ *
+ * This function is called by the kernel to process a BIO for
+ * the P320 device.
+ *
+ * @queue Pointer to the request queue. Unused other than to obtain
+ *              the driver data structure.
+ * @bio   Pointer to the BIO.
+ *
+ */
+static void mtip_make_request(struct request_queue *queue, struct bio *bio)
+{
+       struct driver_data *dd = queue->queuedata;
+       struct scatterlist *sg;
+       struct bio_vec *bvec;
+       int nents = 0;
+       int tag = 0;
+
+       if (unlikely(!bio_has_data(bio))) {
+               blk_queue_flush(queue, 0);
+               bio_endio(bio, 0);
+               return;
+       }
+
+       sg = mtip_hw_get_scatterlist(dd, &tag);
+       if (likely(sg != NULL)) {
+               blk_queue_bounce(queue, &bio);
+
+               if (unlikely((bio)->bi_vcnt > MTIP_MAX_SG)) {
+                       dev_warn(&dd->pdev->dev,
+                               "Maximum number of SGL entries exceeded");
+                       bio_io_error(bio);
+                       mtip_hw_release_scatterlist(dd, tag);
+                       return;
+               }
+
+               /* Create the scatter list for this bio. */
+               bio_for_each_segment(bvec, bio, nents) {
+                       sg_set_page(&sg[nents],
+                                       bvec->bv_page,
+                                       bvec->bv_len,
+                                       bvec->bv_offset);
+               }
+
+               /* Issue the read/write. */
+               mtip_hw_submit_io(dd,
+                               bio->bi_sector,
+                               bio_sectors(bio),
+                               nents,
+                               tag,
+                               bio_endio,
+                               bio,
+                               bio->bi_rw & REQ_FUA,
+                               bio_data_dir(bio));
+       } else
+               bio_io_error(bio);
+}
+
+/*
+ * Block layer initialization function.
+ *
+ * This function is called once by the PCI layer for each P320
+ * device that is connected to the system.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     0 on success else an error code.
+ */
+static int mtip_block_initialize(struct driver_data *dd)
+{
+       int rv = 0, wait_for_rebuild = 0;
+       sector_t capacity;
+       unsigned int index = 0;
+       struct kobject *kobj;
+       unsigned char thd_name[16];
+
+       if (dd->disk)
+               goto skip_create_disk; /* hw init done, before rebuild */
+
+       /* Initialize the protocol layer. */
+       wait_for_rebuild = mtip_hw_init(dd);
+       if (wait_for_rebuild < 0) {
+               dev_err(&dd->pdev->dev,
+                       "Protocol layer initialization failed\n");
+               rv = -EINVAL;
+               goto protocol_init_error;
+       }
+
+       dd->disk = alloc_disk(MTIP_MAX_MINORS);
+       if (dd->disk  == NULL) {
+               dev_err(&dd->pdev->dev,
+                       "Unable to allocate gendisk structure\n");
+               rv = -EINVAL;
+               goto alloc_disk_error;
+       }
+
+       /* Generate the disk name, implemented same as in sd.c */
+       do {
+               if (!ida_pre_get(&rssd_index_ida, GFP_KERNEL))
+                       goto ida_get_error;
+
+               spin_lock(&rssd_index_lock);
+               rv = ida_get_new(&rssd_index_ida, &index);
+               spin_unlock(&rssd_index_lock);
+       } while (rv == -EAGAIN);
+
+       if (rv)
+               goto ida_get_error;
+
+       rv = rssd_disk_name_format("rssd",
+                               index,
+                               dd->disk->disk_name,
+                               DISK_NAME_LEN);
+       if (rv)
+               goto disk_index_error;
+
+       dd->disk->driverfs_dev  = &dd->pdev->dev;
+       dd->disk->major         = dd->major;
+       dd->disk->first_minor   = dd->instance * MTIP_MAX_MINORS;
+       dd->disk->fops          = &mtip_block_ops;
+       dd->disk->private_data  = dd;
+       dd->index               = index;
+
+       /*
+        * if rebuild pending, start the service thread, and delay the block
+        * queue creation and add_disk()
+        */
+       if (wait_for_rebuild == MTIP_FTL_REBUILD_MAGIC)
+               goto start_service_thread;
+
+skip_create_disk:
+       /* Allocate the request queue. */
+       dd->queue = blk_alloc_queue(GFP_KERNEL);
+       if (dd->queue == NULL) {
+               dev_err(&dd->pdev->dev,
+                       "Unable to allocate request queue\n");
+               rv = -ENOMEM;
+               goto block_queue_alloc_init_error;
+       }
+
+       /* Attach our request function to the request queue. */
+       blk_queue_make_request(dd->queue, mtip_make_request);
+
+       dd->disk->queue         = dd->queue;
+       dd->queue->queuedata    = dd;
+
+       /* Set device limits. */
+       set_bit(QUEUE_FLAG_NONROT, &dd->queue->queue_flags);
+       blk_queue_max_segments(dd->queue, MTIP_MAX_SG);
+       blk_queue_physical_block_size(dd->queue, 4096);
+       blk_queue_io_min(dd->queue, 4096);
+       blk_queue_flush(dd->queue, 0);
+
+       /* Set the capacity of the device in 512 byte sectors. */
+       if (!(mtip_hw_get_capacity(dd, &capacity))) {
+               dev_warn(&dd->pdev->dev,
+                       "Could not read drive capacity\n");
+               rv = -EIO;
+               goto read_capacity_error;
+       }
+       set_capacity(dd->disk, capacity);
+
+       /* Enable the block device and add it to /dev */
+       add_disk(dd->disk);
+
+       /*
+        * Now that the disk is active, initialize any sysfs attributes
+        * managed by the protocol layer.
+        */
+       kobj = kobject_get(&disk_to_dev(dd->disk)->kobj);
+       if (kobj) {
+               mtip_hw_sysfs_init(dd, kobj);
+               kobject_put(kobj);
+       }
+
+       if (dd->mtip_svc_handler)
+               return rv; /* service thread created for handling rebuild */
+
+start_service_thread:
+       sprintf(thd_name, "mtip_svc_thd_%02d", index);
+
+       dd->mtip_svc_handler = kthread_run(mtip_service_thread,
+                                               dd, thd_name);
+
+       if (IS_ERR(dd->mtip_svc_handler)) {
+               printk(KERN_ERR "mtip32xx: service thread failed to start\n");
+               dd->mtip_svc_handler = NULL;
+               rv = -EFAULT;
+               goto kthread_run_error;
+       }
+
+       return rv;
+
+kthread_run_error:
+       /* Delete our gendisk. This also removes the device from /dev */
+       del_gendisk(dd->disk);
+
+read_capacity_error:
+       blk_cleanup_queue(dd->queue);
+
+block_queue_alloc_init_error:
+disk_index_error:
+       spin_lock(&rssd_index_lock);
+       ida_remove(&rssd_index_ida, index);
+       spin_unlock(&rssd_index_lock);
+
+ida_get_error:
+       put_disk(dd->disk);
+
+alloc_disk_error:
+       mtip_hw_exit(dd); /* De-initialize the protocol layer. */
+
+protocol_init_error:
+       return rv;
+}
+
+/*
+ * Block layer deinitialization function.
+ *
+ * Called by the PCI layer as each P320 device is removed.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     0
+ */
+static int mtip_block_remove(struct driver_data *dd)
+{
+       struct kobject *kobj;
+
+       if (dd->mtip_svc_handler) {
+               set_bit(MTIP_FLAG_SVC_THD_SHOULD_STOP_BIT, &dd->port->flags);
+               wake_up_interruptible(&dd->port->svc_wait);
+               kthread_stop(dd->mtip_svc_handler);
+       }
+
+       /* Clean up the sysfs attributes managed by the protocol layer. */
+       kobj = kobject_get(&disk_to_dev(dd->disk)->kobj);
+       if (kobj) {
+               mtip_hw_sysfs_exit(dd, kobj);
+               kobject_put(kobj);
+       }
+
+       /*
+        * Delete our gendisk structure. This also removes the device
+        * from /dev
+        */
+       del_gendisk(dd->disk);
+       blk_cleanup_queue(dd->queue);
+       dd->disk  = NULL;
+       dd->queue = NULL;
+
+       /* De-initialize the protocol layer. */
+       mtip_hw_exit(dd);
+
+       return 0;
+}
+
+/*
+ * Function called by the PCI layer when just before the
+ * machine shuts down.
+ *
+ * If a protocol layer shutdown function is present it will be called
+ * by this function.
+ *
+ * @dd Pointer to the driver data structure.
+ *
+ * return value
+ *     0
+ */
+static int mtip_block_shutdown(struct driver_data *dd)
+{
+       dev_info(&dd->pdev->dev,
+               "Shutting down %s ...\n", dd->disk->disk_name);
+
+       /* Delete our gendisk structure, and cleanup the blk queue. */
+       del_gendisk(dd->disk);
+       blk_cleanup_queue(dd->queue);
+       dd->disk  = NULL;
+       dd->queue = NULL;
+
+       mtip_hw_shutdown(dd);
+       return 0;
+}
+
+static int mtip_block_suspend(struct driver_data *dd)
+{
+       dev_info(&dd->pdev->dev,
+               "Suspending %s ...\n", dd->disk->disk_name);
+       mtip_hw_suspend(dd);
+       return 0;
+}
+
+static int mtip_block_resume(struct driver_data *dd)
+{
+       dev_info(&dd->pdev->dev, "Resuming %s ...\n",
+               dd->disk->disk_name);
+       mtip_hw_resume(dd);
+       return 0;
+}
+
+/*
+ * Called for each supported PCI device detected.
+ *
+ * This function allocates the private data structure, enables the
+ * PCI device and then calls the block layer initialization function.
+ *
+ * return value
+ *     0 on success else an error code.
+ */
+static int mtip_pci_probe(struct pci_dev *pdev,
+                       const struct pci_device_id *ent)
+{
+       int rv = 0;
+       struct driver_data *dd = NULL;
+
+       /* Allocate memory for this devices private data. */
+       dd = kzalloc(sizeof(struct driver_data), GFP_KERNEL);
+       if (dd == NULL) {
+               dev_err(&pdev->dev,
+                       "Unable to allocate memory for driver data\n");
+               return -ENOMEM;
+       }
+
+       /* Set the atomic variable as 1 in case of SRSI */
+       atomic_set(&dd->drv_cleanup_done, true);
+
+       atomic_set(&dd->resumeflag, false);
+
+       /* Attach the private data to this PCI device.  */
+       pci_set_drvdata(pdev, dd);
+
+       rv = pcim_enable_device(pdev);
+       if (rv < 0) {
+               dev_err(&pdev->dev, "Unable to enable device\n");
+               goto iomap_err;
+       }
+
+       /* Map BAR5 to memory. */
+       rv = pcim_iomap_regions(pdev, 1 << MTIP_ABAR, MTIP_DRV_NAME);
+       if (rv < 0) {
+               dev_err(&pdev->dev, "Unable to map regions\n");
+               goto iomap_err;
+       }
+
+       if (!pci_set_dma_mask(pdev, DMA_BIT_MASK(64))) {
+               rv = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
+
+               if (rv) {
+                       rv = pci_set_consistent_dma_mask(pdev,
+                                               DMA_BIT_MASK(32));
+                       if (rv) {
+                               dev_warn(&pdev->dev,
+                                       "64-bit DMA enable failed\n");
+                               goto setmask_err;
+                       }
+               }
+       }
+
+       pci_set_master(pdev);
+
+       if (pci_enable_msi(pdev)) {
+               dev_warn(&pdev->dev,
+                       "Unable to enable MSI interrupt.\n");
+               goto block_initialize_err;
+       }
+
+       /* Copy the info we may need later into the private data structure. */
+       dd->major       = mtip_major;
+       dd->instance    = instance;
+       dd->pdev        = pdev;
+
+       /* Initialize the block layer. */
+       rv = mtip_block_initialize(dd);
+       if (rv < 0) {
+               dev_err(&pdev->dev,
+                       "Unable to initialize block layer\n");
+               goto block_initialize_err;
+       }
+
+       /*
+        * Increment the instance count so that each device has a unique
+        * instance number.
+        */
+       instance++;
+
+       goto done;
+
+block_initialize_err:
+       pci_disable_msi(pdev);
+
+setmask_err:
+       pcim_iounmap_regions(pdev, 1 << MTIP_ABAR);
+
+iomap_err:
+       kfree(dd);
+       pci_set_drvdata(pdev, NULL);
+       return rv;
+done:
+       /* Set the atomic variable as 0 in case of SRSI */
+       atomic_set(&dd->drv_cleanup_done, true);
+
+       return rv;
+}
+
+/*
+ * Called for each probed device when the device is removed or the
+ * driver is unloaded.
+ *
+ * return value
+ *     None
+ */
+static void mtip_pci_remove(struct pci_dev *pdev)
+{
+       struct driver_data *dd = pci_get_drvdata(pdev);
+       int counter = 0;
+
+       if (mtip_check_surprise_removal(pdev)) {
+               while (atomic_read(&dd->drv_cleanup_done) == false) {
+                       counter++;
+                       msleep(20);
+                       if (counter == 10) {
+                               /* Cleanup the outstanding commands */
+                               mtip_command_cleanup(dd);
+                               break;
+                       }
+               }
+       }
+       /* Set the atomic variable as 1 in case of SRSI */
+       atomic_set(&dd->drv_cleanup_done, true);
+
+       /* Clean up the block layer. */
+       mtip_block_remove(dd);
+
+       pci_disable_msi(pdev);
+
+       kfree(dd);
+       pcim_iounmap_regions(pdev, 1 << MTIP_ABAR);
+}
+
+/*
+ * Called for each probed device when the device is suspended.
+ *
+ * return value
+ *     0  Success
+ *     <0 Error
+ */
+static int mtip_pci_suspend(struct pci_dev *pdev, pm_message_t mesg)
+{
+       int rv = 0;
+       struct driver_data *dd = pci_get_drvdata(pdev);
+
+       if (!dd) {
+               dev_err(&pdev->dev,
+                       "Driver private datastructure is NULL\n");
+               return -EFAULT;
+       }
+
+       atomic_set(&dd->resumeflag, true);
+
+       /* Disable ports & interrupts then send standby immediate */
+       rv = mtip_block_suspend(dd);
+       if (rv < 0) {
+               dev_err(&pdev->dev,
+                       "Failed to suspend controller\n");
+               return rv;
+       }
+
+       /*
+        * Save the pci config space to pdev structure &
+        * disable the device
+        */
+       pci_save_state(pdev);
+       pci_disable_device(pdev);
+
+       /* Move to Low power state*/
+       pci_set_power_state(pdev, PCI_D3hot);
+
+       return rv;
+}
+
+/*
+ * Called for each probed device when the device is resumed.
+ *
+ * return value
+ *      0  Success
+ *      <0 Error
+ */
+static int mtip_pci_resume(struct pci_dev *pdev)
+{
+       int rv = 0;
+       struct driver_data *dd;
+
+       dd = pci_get_drvdata(pdev);
+       if (!dd) {
+               dev_err(&pdev->dev,
+                       "Driver private datastructure is NULL\n");
+               return -EFAULT;
+       }
+
+       /* Move the device to active State */
+       pci_set_power_state(pdev, PCI_D0);
+
+       /* Restore PCI configuration space */
+       pci_restore_state(pdev);
+
+       /* Enable the PCI device*/
+       rv = pcim_enable_device(pdev);
+       if (rv < 0) {
+               dev_err(&pdev->dev,
+                       "Failed to enable card during resume\n");
+               goto err;
+       }
+       pci_set_master(pdev);
+
+       /*
+        * Calls hbaReset, initPort, & startPort function
+        * then enables interrupts
+        */
+       rv = mtip_block_resume(dd);
+       if (rv < 0)
+               dev_err(&pdev->dev, "Unable to resume\n");
+
+err:
+       atomic_set(&dd->resumeflag, false);
+
+       return rv;
+}
+
+/*
+ * Shutdown routine
+ *
+ * return value
+ *      None
+ */
+static void mtip_pci_shutdown(struct pci_dev *pdev)
+{
+       struct driver_data *dd = pci_get_drvdata(pdev);
+       if (dd)
+               mtip_block_shutdown(dd);
+}
+
+/* Table of device ids supported by this driver. */
+static DEFINE_PCI_DEVICE_TABLE(mtip_pci_tbl) = {
+       {  PCI_DEVICE(PCI_VENDOR_ID_MICRON, P320_DEVICE_ID) },
+       { 0 }
+};
+
+/* Structure that describes the PCI driver functions. */
+static struct pci_driver mtip_pci_driver = {
+       .name                   = MTIP_DRV_NAME,
+       .id_table               = mtip_pci_tbl,
+       .probe                  = mtip_pci_probe,
+       .remove                 = mtip_pci_remove,
+       .suspend                = mtip_pci_suspend,
+       .resume                 = mtip_pci_resume,
+       .shutdown               = mtip_pci_shutdown,
+};
+
+MODULE_DEVICE_TABLE(pci, mtip_pci_tbl);
+
+/*
+ * Module initialization function.
+ *
+ * Called once when the module is loaded. This function allocates a major
+ * block device number to the Cyclone devices and registers the PCI layer
+ * of the driver.
+ *
+ * Return value
+ *      0 on success else error code.
+ */
+static int __init mtip_init(void)
+{
+       printk(KERN_INFO MTIP_DRV_NAME " Version " MTIP_DRV_VERSION "\n");
+
+       /* Allocate a major block device number to use with this driver. */
+       mtip_major = register_blkdev(0, MTIP_DRV_NAME);
+       if (mtip_major < 0) {
+               printk(KERN_ERR "Unable to register block device (%d)\n",
+               mtip_major);
+               return -EBUSY;
+       }
+
+       /* Register our PCI operations. */
+       return pci_register_driver(&mtip_pci_driver);
+}
+
+/*
+ * Module de-initialization function.
+ *
+ * Called once when the module is unloaded. This function deallocates
+ * the major block device number allocated by mtip_init() and
+ * unregisters the PCI layer of the driver.
+ *
+ * Return value
+ *      none
+ */
+static void __exit mtip_exit(void)
+{
+       /* Release the allocated major block device number. */
+       unregister_blkdev(mtip_major, MTIP_DRV_NAME);
+
+       /* Unregister the PCI driver. */
+       pci_unregister_driver(&mtip_pci_driver);
+}
+
+MODULE_AUTHOR("Micron Technology, Inc");
+MODULE_DESCRIPTION("Micron RealSSD PCIe Block Driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(MTIP_DRV_VERSION);
+
+module_init(mtip_init);
+module_exit(mtip_exit);
diff --git a/drivers/block/mtip32xx/mtip32xx.h b/drivers/block/mtip32xx/mtip32xx.h
new file mode 100644 (file)
index 0000000..723d7c4
--- /dev/null
@@ -0,0 +1,423 @@
+/*
+ * mtip32xx.h - Header file for the P320 SSD Block Driver
+ *   Copyright (C) 2011 Micron Technology, Inc.
+ *
+ * Portions of this code were derived from works subjected to the
+ * following copyright:
+ *    Copyright (C) 2009 Integrated Device Technology, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __MTIP32XX_H__
+#define __MTIP32XX_H__
+
+#include <linux/spinlock.h>
+#include <linux/rwsem.h>
+#include <linux/ata.h>
+#include <linux/interrupt.h>
+#include <linux/genhd.h>
+#include <linux/version.h>
+
+/* Offset of Subsystem Device ID in pci confoguration space */
+#define PCI_SUBSYSTEM_DEVICEID 0x2E
+
+/* offset of Device Control register in PCIe extended capabilites space */
+#define PCIE_CONFIG_EXT_DEVICE_CONTROL_OFFSET  0x48
+
+/* # of times to retry timed out IOs */
+#define MTIP_MAX_RETRIES       5
+
+/* Various timeout values in ms */
+#define MTIP_NCQ_COMMAND_TIMEOUT_MS       5000
+#define MTIP_IOCTL_COMMAND_TIMEOUT_MS     5000
+#define MTIP_INTERNAL_COMMAND_TIMEOUT_MS  5000
+
+/* check for timeouts every 500ms */
+#define MTIP_TIMEOUT_CHECK_PERIOD      500
+
+/* ftl rebuild */
+#define MTIP_FTL_REBUILD_OFFSET                142
+#define MTIP_FTL_REBUILD_MAGIC         0xED51
+#define MTIP_FTL_REBUILD_TIMEOUT_MS    2400000
+
+/* Macro to extract the tag bit number from a tag value. */
+#define MTIP_TAG_BIT(tag)      (tag & 0x1F)
+
+/*
+ * Macro to extract the tag index from a tag value. The index
+ * is used to access the correct s_active/Command Issue register based
+ * on the tag value.
+ */
+#define MTIP_TAG_INDEX(tag)    (tag >> 5)
+
+/*
+ * Maximum number of scatter gather entries
+ * a single command may have.
+ */
+#define MTIP_MAX_SG            128
+
+/*
+ * Maximum number of slot groups (Command Issue & s_active registers)
+ * NOTE: This is the driver maximum; check dd->slot_groups for actual value.
+ */
+#define MTIP_MAX_SLOT_GROUPS   8
+
+/* Internal command tag. */
+#define MTIP_TAG_INTERNAL      0
+
+/* Micron Vendor ID & P320x SSD Device ID */
+#define PCI_VENDOR_ID_MICRON    0x1344
+#define P320_DEVICE_ID         0x5150
+
+/* Driver name and version strings */
+#define MTIP_DRV_NAME          "mtip32xx"
+#define MTIP_DRV_VERSION       "1.2.6os3"
+
+/* Maximum number of minor device numbers per device. */
+#define MTIP_MAX_MINORS                16
+
+/* Maximum number of supported command slots. */
+#define MTIP_MAX_COMMAND_SLOTS (MTIP_MAX_SLOT_GROUPS * 32)
+
+/*
+ * Per-tag bitfield size in longs.
+ * Linux bit manipulation functions
+ * (i.e. test_and_set_bit, find_next_zero_bit)
+ * manipulate memory in longs, so we try to make the math work.
+ * take the slot groups and find the number of longs, rounding up.
+ * Careful! i386 and x86_64 use different size longs!
+ */
+#define U32_PER_LONG   (sizeof(long) / sizeof(u32))
+#define SLOTBITS_IN_LONGS ((MTIP_MAX_SLOT_GROUPS + \
+                                       (U32_PER_LONG-1))/U32_PER_LONG)
+
+/* BAR number used to access the HBA registers. */
+#define MTIP_ABAR              5
+
+/* Forced Unit Access Bit */
+#define FUA_BIT                        0x80
+
+#ifdef DEBUG
+ #define dbg_printk(format, arg...)    \
+       printk(pr_fmt(format), ##arg);
+#else
+ #define dbg_printk(format, arg...)
+#endif
+
+#define __force_bit2int (unsigned int __force)
+
+/* below are bit numbers in 'flags' defined in mtip_port */
+#define MTIP_FLAG_IC_ACTIVE_BIT                        0
+#define MTIP_FLAG_EH_ACTIVE_BIT                        1
+#define MTIP_FLAG_SVC_THD_ACTIVE_BIT           2
+#define MTIP_FLAG_ISSUE_CMDS_BIT               4
+#define MTIP_FLAG_REBUILD_BIT                  5
+#define MTIP_FLAG_SVC_THD_SHOULD_STOP_BIT      8
+
+/* Register Frame Information Structure (FIS), host to device. */
+struct host_to_dev_fis {
+       /*
+        * FIS type.
+        * - 27h Register FIS, host to device.
+        * - 34h Register FIS, device to host.
+        * - 39h DMA Activate FIS, device to host.
+        * - 41h DMA Setup FIS, bi-directional.
+        * - 46h Data FIS, bi-directional.
+        * - 58h BIST Activate FIS, bi-directional.
+        * - 5Fh PIO Setup FIS, device to host.
+        * - A1h Set Device Bits FIS, device to host.
+        */
+       unsigned char type;
+       unsigned char opts;
+       unsigned char command;
+       unsigned char features;
+
+       union {
+               unsigned char lba_low;
+               unsigned char sector;
+       };
+       union {
+               unsigned char lba_mid;
+               unsigned char cyl_low;
+       };
+       union {
+               unsigned char lba_hi;
+               unsigned char cyl_hi;
+       };
+       union {
+               unsigned char device;
+               unsigned char head;
+       };
+
+       union {
+               unsigned char lba_low_ex;
+               unsigned char sector_ex;
+       };
+       union {
+               unsigned char lba_mid_ex;
+               unsigned char cyl_low_ex;
+       };
+       union {
+               unsigned char lba_hi_ex;
+               unsigned char cyl_hi_ex;
+       };
+       unsigned char features_ex;
+
+       unsigned char sect_count;
+       unsigned char sect_cnt_ex;
+       unsigned char res2;
+       unsigned char control;
+
+       unsigned int res3;
+};
+
+/* Command header structure. */
+struct mtip_cmd_hdr {
+       /*
+        * Command options.
+        * - Bits 31:16 Number of PRD entries.
+        * - Bits 15:8 Unused in this implementation.
+        * - Bit 7 Prefetch bit, informs the drive to prefetch PRD entries.
+        * - Bit 6 Write bit, should be set when writing data to the device.
+        * - Bit 5 Unused in this implementation.
+        * - Bits 4:0 Length of the command FIS in DWords (DWord = 4 bytes).
+        */
+       unsigned int opts;
+       /* This field is unsed when using NCQ. */
+       union {
+               unsigned int byte_count;
+               unsigned int status;
+       };
+       /*
+        * Lower 32 bits of the command table address associated with this
+        * header. The command table addresses must be 128 byte aligned.
+        */
+       unsigned int ctba;
+       /*
+        * If 64 bit addressing is used this field is the upper 32 bits
+        * of the command table address associated with this command.
+        */
+       unsigned int ctbau;
+       /* Reserved and unused. */
+       unsigned int res[4];
+};
+
+/* Command scatter gather structure (PRD). */
+struct mtip_cmd_sg {
+       /*
+        * Low 32 bits of the data buffer address. For P320 this
+        * address must be 8 byte aligned signified by bits 2:0 being
+        * set to 0.
+        */
+       unsigned int dba;
+       /*
+        * When 64 bit addressing is used this field is the upper
+        * 32 bits of the data buffer address.
+        */
+       unsigned int dba_upper;
+       /* Unused. */
+       unsigned int reserved;
+       /*
+        * Bit 31: interrupt when this data block has been transferred.
+        * Bits 30..22: reserved
+        * Bits 21..0: byte count (minus 1).  For P320 the byte count must be
+        * 8 byte aligned signified by bits 2:0 being set to 1.
+        */
+       unsigned int info;
+};
+struct mtip_port;
+
+/* Structure used to describe a command. */
+struct mtip_cmd {
+
+       struct mtip_cmd_hdr *command_header; /* ptr to command header entry */
+
+       dma_addr_t command_header_dma; /* corresponding physical address */
+
+       void *command; /* ptr to command table entry */
+
+       dma_addr_t command_dma; /* corresponding physical address */
+
+       void *comp_data; /* data passed to completion function comp_func() */
+       /*
+        * Completion function called by the ISR upon completion of
+        * a command.
+        */
+       void (*comp_func)(struct mtip_port *port,
+                               int tag,
+                               void *data,
+                               int status);
+       /* Additional callback function that may be called by comp_func() */
+       void (*async_callback)(void *data, int status);
+
+       void *async_data; /* Addl. data passed to async_callback() */
+
+       int scatter_ents; /* Number of scatter list entries used */
+
+       struct scatterlist sg[MTIP_MAX_SG]; /* Scatter list entries */
+
+       int retries; /* The number of retries left for this command. */
+
+       int direction; /* Data transfer direction */
+
+       unsigned long comp_time; /* command completion time, in jiffies */
+
+       atomic_t active; /* declares if this command sent to the drive. */
+};
+
+/* Structure used to describe a port. */
+struct mtip_port {
+       /* Pointer back to the driver data for this port. */
+       struct driver_data *dd;
+       /*
+        * Used to determine if the data pointed to by the
+        * identify field is valid.
+        */
+       unsigned long identify_valid;
+       /* Base address of the memory mapped IO for the port. */
+       void __iomem *mmio;
+       /* Array of pointers to the memory mapped s_active registers. */
+       void __iomem *s_active[MTIP_MAX_SLOT_GROUPS];
+       /* Array of pointers to the memory mapped completed registers. */
+       void __iomem *completed[MTIP_MAX_SLOT_GROUPS];
+       /* Array of pointers to the memory mapped Command Issue registers. */
+       void __iomem *cmd_issue[MTIP_MAX_SLOT_GROUPS];
+       /*
+        * Pointer to the beginning of the command header memory as used
+        * by the driver.
+        */
+       void *command_list;
+       /*
+        * Pointer to the beginning of the command header memory as used
+        * by the DMA.
+        */
+       dma_addr_t command_list_dma;
+       /*
+        * Pointer to the beginning of the RX FIS memory as used
+        * by the driver.
+        */
+       void *rxfis;
+       /*
+        * Pointer to the beginning of the RX FIS memory as used
+        * by the DMA.
+        */
+       dma_addr_t rxfis_dma;
+       /*
+        * Pointer to the beginning of the command table memory as used
+        * by the driver.
+        */
+       void *command_table;
+       /*
+        * Pointer to the beginning of the command table memory as used
+        * by the DMA.
+        */
+       dma_addr_t command_tbl_dma;
+       /*
+        * Pointer to the beginning of the identify data memory as used
+        * by the driver.
+        */
+       u16 *identify;
+       /*
+        * Pointer to the beginning of the identify data memory as used
+        * by the DMA.
+        */
+       dma_addr_t identify_dma;
+       /*
+        * Pointer to the beginning of a sector buffer that is used
+        * by the driver when issuing internal commands.
+        */
+       u16 *sector_buffer;
+       /*
+        * Pointer to the beginning of a sector buffer that is used
+        * by the DMA when the driver issues internal commands.
+        */
+       dma_addr_t sector_buffer_dma;
+       /*
+        * Bit significant, used to determine if a command slot has
+        * been allocated. i.e. the slot is in use.  Bits are cleared
+        * when the command slot and all associated data structures
+        * are no longer needed.
+        */
+       unsigned long allocated[SLOTBITS_IN_LONGS];
+       /*
+        * used to queue commands when an internal command is in progress
+        * or error handling is active
+        */
+       unsigned long cmds_to_issue[SLOTBITS_IN_LONGS];
+       /*
+        * Array of command slots. Structure includes pointers to the
+        * command header and command table, and completion function and data
+        * pointers.
+        */
+       struct mtip_cmd commands[MTIP_MAX_COMMAND_SLOTS];
+       /* Used by mtip_service_thread to wait for an event */
+       wait_queue_head_t svc_wait;
+       /*
+        * indicates the state of the port. Also, helps the service thread
+        * to determine its action on wake up.
+        */
+       unsigned long flags;
+       /*
+        * Timer used to complete commands that have been active for too long.
+        */
+       struct timer_list cmd_timer;
+       /*
+        * Semaphore used to block threads if there are no
+        * command slots available.
+        */
+       struct semaphore cmd_slot;
+       /* Spinlock for working around command-issue bug. */
+       spinlock_t cmd_issue_lock;
+};
+
+/*
+ * Driver private data structure.
+ *
+ * One structure is allocated per probed device.
+ */
+struct driver_data {
+       void __iomem *mmio; /* Base address of the HBA registers. */
+
+       int major; /* Major device number. */
+
+       int instance; /* Instance number. First device probed is 0, ... */
+
+       struct gendisk *disk; /* Pointer to our gendisk structure. */
+
+       struct pci_dev *pdev; /* Pointer to the PCI device structure. */
+
+       struct request_queue *queue; /* Our request queue. */
+
+       struct mtip_port *port; /* Pointer to the port data structure. */
+
+       /* Tasklet used to process the bottom half of the ISR. */
+       struct tasklet_struct tasklet;
+
+       unsigned product_type; /* magic value declaring the product type */
+
+       unsigned slot_groups; /* number of slot groups the product supports */
+
+       atomic_t drv_cleanup_done; /* Atomic variable for SRSI */
+
+       unsigned long index; /* Index to determine the disk name */
+
+       unsigned int ftlrebuildflag; /* FTL rebuild flag */
+
+       atomic_t resumeflag; /* Atomic variable to track suspend/resume */
+
+       atomic_t eh_active; /* Flag for error handling tracking */
+
+       struct task_struct *mtip_svc_handler; /* task_struct of svc thd */
+};
+
+#endif