/*
* Dynamic DMA mapping support.
*
- * This implementation is for IA-64 platforms that do not support
+ * This implementation is for IA-64 and EM64T platforms that do not support
* I/O TLBs (aka DMA address translation hardware).
* Copyright (C) 2000 Asit Mallick <Asit.K.Mallick@intel.com>
* Copyright (C) 2000 Goutham Rao <goutham.rao@intel.com>
* 03/05/07 davidm Switch from PCI-DMA to generic device DMA API.
* 00/12/13 davidm Rename to swiotlb.c and add mark_clean() to avoid
* unnecessary i-cache flushing.
- * 04/07/.. ak Better overflow handling. Assorted fixes.
+ * 04/07/.. ak Better overflow handling. Assorted fixes.
+ * 05/09/10 linville Add support for syncing ranges, support syncing for
+ * DMA_BIDIRECTIONAL mappings, miscellaneous cleanup.
*/
#include <linux/cache.h>
+#include <linux/dma-mapping.h>
#include <linux/mm.h>
#include <linux/module.h>
-#include <linux/pci.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/ctype.h>
#include <asm/io.h>
-#include <asm/pci.h>
#include <asm/dma.h>
+#include <asm/scatterlist.h>
#include <linux/init.h>
#include <linux/bootmem.h>
*/
#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
+/*
+ * Enumeration for sync targets
+ */
+enum dma_sync_target {
+ SYNC_FOR_CPU = 0,
+ SYNC_FOR_DEVICE = 1,
+};
+
int swiotlb_force;
/*
/*
* Statically reserve bounce buffer space and initialize bounce buffer data
- * structures for the software IO TLB used to implement the PCI DMA API.
+ * structures for the software IO TLB used to implement the DMA API.
*/
void
swiotlb_init_with_default_size (size_t default_size)
}
static void
-sync_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
+sync_single(struct device *hwdev, char *dma_addr, size_t size,
+ int dir, int target)
{
int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
char *buffer = io_tlb_orig_addr[index];
- /*
- * bounce... copy the data back into/from the original buffer
- * XXX How do you handle DMA_BIDIRECTIONAL here ?
- */
- if (dir == DMA_FROM_DEVICE)
- memcpy(buffer, dma_addr, size);
- else if (dir == DMA_TO_DEVICE)
- memcpy(dma_addr, buffer, size);
- else
+ switch (target) {
+ case SYNC_FOR_CPU:
+ if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
+ memcpy(buffer, dma_addr, size);
+ else if (dir != DMA_TO_DEVICE)
+ BUG();
+ break;
+ case SYNC_FOR_DEVICE:
+ if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
+ memcpy(dma_addr, buffer, size);
+ else if (dir != DMA_FROM_DEVICE)
+ BUG();
+ break;
+ default:
BUG();
+ }
}
void *
/*
* Ran out of IOMMU space for this operation. This is very bad.
* Unfortunately the drivers cannot handle this operation properly.
- * unless they check for pci_dma_mapping_error (most don't)
+ * unless they check for dma_mapping_error (most don't)
* When the mapping is small enough return a static buffer to limit
* the damage, or panic when the transfer is too big.
*/
- printk(KERN_ERR "PCI-DMA: Out of SW-IOMMU space for %lu bytes at "
+ printk(KERN_ERR "DMA: Out of SW-IOMMU space for %lu bytes at "
"device %s\n", size, dev ? dev->bus_id : "?");
if (size > io_tlb_overflow && do_panic) {
- if (dir == PCI_DMA_FROMDEVICE || dir == PCI_DMA_BIDIRECTIONAL)
- panic("PCI-DMA: Memory would be corrupted\n");
- if (dir == PCI_DMA_TODEVICE || dir == PCI_DMA_BIDIRECTIONAL)
- panic("PCI-DMA: Random memory would be DMAed\n");
+ if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
+ panic("DMA: Memory would be corrupted\n");
+ if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
+ panic("DMA: Random memory would be DMAed\n");
}
}
/*
* Map a single buffer of the indicated size for DMA in streaming mode. The
- * PCI address to use is returned.
+ * physical address to use is returned.
*
* Once the device is given the dma address, the device owns this memory until
* either swiotlb_unmap_single or swiotlb_dma_sync_single is performed.
* after a transfer.
*
* If you perform a swiotlb_map_single() but wish to interrogate the buffer
- * using the cpu, yet do not wish to teardown the PCI dma mapping, you must
- * call this function before doing so. At the next point you give the PCI dma
+ * using the cpu, yet do not wish to teardown the dma mapping, you must
+ * call this function before doing so. At the next point you give the dma
* address back to the card, you must first perform a
* swiotlb_dma_sync_for_device, and then the device again owns the buffer
*/
-void
-swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, int dir)
+static inline void
+swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, int dir, int target)
{
char *dma_addr = phys_to_virt(dev_addr);
if (dir == DMA_NONE)
BUG();
if (dma_addr >= io_tlb_start && dma_addr < io_tlb_end)
- sync_single(hwdev, dma_addr, size, dir);
+ sync_single(hwdev, dma_addr, size, dir, target);
else if (dir == DMA_FROM_DEVICE)
mark_clean(dma_addr, size);
}
+void
+swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, int dir)
+{
+ swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
+}
+
void
swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
size_t size, int dir)
{
- char *dma_addr = phys_to_virt(dev_addr);
+ swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
+}
+
+/*
+ * Same as above, but for a sub-range of the mapping.
+ */
+static inline void
+swiotlb_sync_single_range(struct device *hwdev, dma_addr_t dev_addr,
+ unsigned long offset, size_t size,
+ int dir, int target)
+{
+ char *dma_addr = phys_to_virt(dev_addr) + offset;
if (dir == DMA_NONE)
BUG();
if (dma_addr >= io_tlb_start && dma_addr < io_tlb_end)
- sync_single(hwdev, dma_addr, size, dir);
+ sync_single(hwdev, dma_addr, size, dir, target);
else if (dir == DMA_FROM_DEVICE)
mark_clean(dma_addr, size);
}
+void
+swiotlb_sync_single_range_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
+ unsigned long offset, size_t size, int dir)
+{
+ swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
+ SYNC_FOR_CPU);
+}
+
+void
+swiotlb_sync_single_range_for_device(struct device *hwdev, dma_addr_t dev_addr,
+ unsigned long offset, size_t size, int dir)
+{
+ swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
+ SYNC_FOR_DEVICE);
+}
+
/*
* Map a set of buffers described by scatterlist in streaming mode for DMA.
* This is the scatter-gather version of the above swiotlb_map_single
* The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
* and usage.
*/
-void
-swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
- int nelems, int dir)
+static inline void
+swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sg,
+ int nelems, int dir, int target)
{
int i;
for (i = 0; i < nelems; i++, sg++)
if (sg->dma_address != SG_ENT_PHYS_ADDRESS(sg))
sync_single(hwdev, (void *) sg->dma_address,
- sg->dma_length, dir);
+ sg->dma_length, dir, target);
+}
+
+void
+swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
+ int nelems, int dir)
+{
+ swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
}
void
swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
int nelems, int dir)
{
- int i;
-
- if (dir == DMA_NONE)
- BUG();
-
- for (i = 0; i < nelems; i++, sg++)
- if (sg->dma_address != SG_ENT_PHYS_ADDRESS(sg))
- sync_single(hwdev, (void *) sg->dma_address,
- sg->dma_length, dir);
+ swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
}
int
}
/*
- * Return whether the given PCI device DMA address mask can be supported
+ * Return whether the given device DMA address mask can be supported
* properly. For example, if your device can only drive the low 24-bits
- * during PCI bus mastering, then you would pass 0x00ffffff as the mask to
+ * during bus mastering, then you would pass 0x00ffffff as the mask to
* this function.
*/
int
EXPORT_SYMBOL(swiotlb_unmap_sg);
EXPORT_SYMBOL(swiotlb_sync_single_for_cpu);
EXPORT_SYMBOL(swiotlb_sync_single_for_device);
+EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_cpu);
+EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_device);
EXPORT_SYMBOL(swiotlb_sync_sg_for_cpu);
EXPORT_SYMBOL(swiotlb_sync_sg_for_device);
EXPORT_SYMBOL(swiotlb_dma_mapping_error);