arch/powerpc/platforms/iseries/irq.c

   1 /*
   2  * This module supports the iSeries PCI bus interrupt handling
   3  * Copyright (C) 20yy  <Robert L Holtorf> <IBM Corp>
   4  * Copyright (C) 2004-2005 IBM Corporation
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the:
  18  * Free Software Foundation, Inc.,
  19  * 59 Temple Place, Suite 330,
  20  * Boston, MA  02111-1307  USA
  21  *
  22  * Change Activity:
  23  *   Created, December 13, 2000 by Wayne Holm
  24  * End Change Activity
  25  */
  26 #include <linux/config.h>
  27 #include <linux/pci.h>
  28 #include <linux/init.h>
  29 #include <linux/threads.h>
  30 #include <linux/smp.h>
  31 #include <linux/param.h>
  32 #include <linux/string.h>
  33 #include <linux/bootmem.h>
  34 #include <linux/ide.h>
  35 #include <linux/irq.h>
  36 #include <linux/spinlock.h>
  37
  38 #include <asm/iseries/hv_types.h>
  39 #include <asm/iseries/hv_lp_event.h>
  40 #include <asm/iseries/hv_call_xm.h>
  41
  42 #include "irq.h"
  43 #include "call_pci.h"
  44
  45 /* This maps virtual irq numbers to real irqs */
  46 unsigned int virt_irq_to_real_map[NR_IRQS];
  47
  48 /* The next available virtual irq number */
  49 /* Note: the pcnet32 driver assumes irq numbers < 2 aren't valid. :( */
  50 static int next_virtual_irq = 2;
  51
  52 static long Pci_Interrupt_Count;
  53 static long Pci_Event_Count;
  54
  55 enum XmPciLpEvent_Subtype {
  56         XmPciLpEvent_BusCreated         = 0,    // PHB has been created
  57         XmPciLpEvent_BusError           = 1,    // PHB has failed
  58         XmPciLpEvent_BusFailed          = 2,    // Msg to Secondary, Primary failed bus
  59         XmPciLpEvent_NodeFailed         = 4,    // Multi-adapter bridge has failed
  60         XmPciLpEvent_NodeRecovered      = 5,    // Multi-adapter bridge has recovered
  61         XmPciLpEvent_BusRecovered       = 12,   // PHB has been recovered
  62         XmPciLpEvent_UnQuiesceBus       = 18,   // Secondary bus unqiescing
  63         XmPciLpEvent_BridgeError        = 21,   // Bridge Error
  64         XmPciLpEvent_SlotInterrupt      = 22    // Slot interrupt
  65 };
  66
  67 struct XmPciLpEvent_BusInterrupt {
  68         HvBusNumber     busNumber;
  69         HvSubBusNumber  subBusNumber;
  70 };
  71
  72 struct XmPciLpEvent_NodeInterrupt {
  73         HvBusNumber     busNumber;
  74         HvSubBusNumber  subBusNumber;
  75         HvAgentId       deviceId;
  76 };
  77
  78 struct XmPciLpEvent {
  79         struct HvLpEvent hvLpEvent;
  80
  81         union {
  82                 u64 alignData;                  // Align on an 8-byte boundary
  83
  84                 struct {
  85                         u32             fisr;
  86                         HvBusNumber     busNumber;
  87                         HvSubBusNumber  subBusNumber;
  88                         HvAgentId       deviceId;
  89                 } slotInterrupt;
  90
  91                 struct XmPciLpEvent_BusInterrupt busFailed;
  92                 struct XmPciLpEvent_BusInterrupt busRecovered;
  93                 struct XmPciLpEvent_BusInterrupt busCreated;
  94
  95                 struct XmPciLpEvent_NodeInterrupt nodeFailed;
  96                 struct XmPciLpEvent_NodeInterrupt nodeRecovered;
  97
  98         } eventData;
  99
 100 };
 101
 102 static void intReceived(struct XmPciLpEvent *eventParm,
 103                 struct pt_regs *regsParm)
 104 {
 105         int irq;
 106 #ifdef CONFIG_IRQSTACKS
 107         struct thread_info *curtp, *irqtp;
 108 #endif
 109
 110         ++Pci_Interrupt_Count;
 111
 112         switch (eventParm->hvLpEvent.xSubtype) {
 113         case XmPciLpEvent_SlotInterrupt:
 114                 irq = eventParm->hvLpEvent.xCorrelationToken;
 115                 /* Dispatch the interrupt handlers for this irq */
 116 #ifdef CONFIG_IRQSTACKS
 117                 /* Switch to the irq stack to handle this */
 118                 curtp = current_thread_info();
 119                 irqtp = hardirq_ctx[smp_processor_id()];
 120                 if (curtp != irqtp) {
 121                         irqtp->task = curtp->task;
 122                         irqtp->flags = 0;
 123                         call_ppc_irq_dispatch_handler(regsParm, irq, irqtp);
 124                         irqtp->task = NULL;
 125                         if (irqtp->flags)
 126                                 set_bits(irqtp->flags, &curtp->flags);
 127                 } else
 128 #endif
 129                         ppc_irq_dispatch_handler(regsParm, irq);
 130                 HvCallPci_eoi(eventParm->eventData.slotInterrupt.busNumber,
 131                         eventParm->eventData.slotInterrupt.subBusNumber,
 132                         eventParm->eventData.slotInterrupt.deviceId);
 133                 break;
 134                 /* Ignore error recovery events for now */
 135         case XmPciLpEvent_BusCreated:
 136                 printk(KERN_INFO "intReceived: system bus %d created\n",
 137                         eventParm->eventData.busCreated.busNumber);
 138                 break;
 139         case XmPciLpEvent_BusError:
 140         case XmPciLpEvent_BusFailed:
 141                 printk(KERN_INFO "intReceived: system bus %d failed\n",
 142                         eventParm->eventData.busFailed.busNumber);
 143                 break;
 144         case XmPciLpEvent_BusRecovered:
 145         case XmPciLpEvent_UnQuiesceBus:
 146                 printk(KERN_INFO "intReceived: system bus %d recovered\n",
 147                         eventParm->eventData.busRecovered.busNumber);
 148                 break;
 149         case XmPciLpEvent_NodeFailed:
 150         case XmPciLpEvent_BridgeError:
 151                 printk(KERN_INFO
 152                         "intReceived: multi-adapter bridge %d/%d/%d failed\n",
 153                         eventParm->eventData.nodeFailed.busNumber,
 154                         eventParm->eventData.nodeFailed.subBusNumber,
 155                         eventParm->eventData.nodeFailed.deviceId);
 156                 break;
 157         case XmPciLpEvent_NodeRecovered:
 158                 printk(KERN_INFO
 159                         "intReceived: multi-adapter bridge %d/%d/%d recovered\n",
 160                         eventParm->eventData.nodeRecovered.busNumber,
 161                         eventParm->eventData.nodeRecovered.subBusNumber,
 162                         eventParm->eventData.nodeRecovered.deviceId);
 163                 break;
 164         default:
 165                 printk(KERN_ERR
 166                         "intReceived: unrecognized event subtype 0x%x\n",
 167                         eventParm->hvLpEvent.xSubtype);
 168                 break;
 169         }
 170 }
 171
 172 static void XmPciLpEvent_handler(struct HvLpEvent *eventParm,
 173                 struct pt_regs *regsParm)
 174 {
 175 #ifdef CONFIG_PCI
 176         ++Pci_Event_Count;
 177
 178         if (eventParm && (eventParm->xType == HvLpEvent_Type_PciIo)) {
 179                 switch (eventParm->xFlags.xFunction) {
 180                 case HvLpEvent_Function_Int:
 181                         intReceived((struct XmPciLpEvent *)eventParm, regsParm);
 182                         break;
 183                 case HvLpEvent_Function_Ack:
 184                         printk(KERN_ERR
 185                                 "XmPciLpEvent_handler: unexpected ack received\n");
 186                         break;
 187                 default:
 188                         printk(KERN_ERR
 189                                 "XmPciLpEvent_handler: unexpected event function %d\n",
 190                                 (int)eventParm->xFlags.xFunction);
 191                         break;
 192                 }
 193         } else if (eventParm)
 194                 printk(KERN_ERR
 195                         "XmPciLpEvent_handler: Unrecognized PCI event type 0x%x\n",
 196                         (int)eventParm->xType);
 197         else
 198                 printk(KERN_ERR "XmPciLpEvent_handler: NULL event received\n");
 199 #endif
 200 }
 201
 202 /*
 203  * This is called by init_IRQ.  set in ppc_md.init_IRQ by iSeries_setup.c
 204  * It must be called before the bus walk.
 205  */
 206 void __init iSeries_init_IRQ(void)
 207 {
 208         /* Register PCI event handler and open an event path */
 209         int xRc;
 210
 211         xRc = HvLpEvent_registerHandler(HvLpEvent_Type_PciIo,
 212                         &XmPciLpEvent_handler);
 213         if (xRc == 0) {
 214                 xRc = HvLpEvent_openPath(HvLpEvent_Type_PciIo, 0);
 215                 if (xRc != 0)
 216                         printk(KERN_ERR "iSeries_init_IRQ: open event path "
 217                                         "failed with rc 0x%x\n", xRc);
 218         } else
 219                 printk(KERN_ERR "iSeries_init_IRQ: register handler "
 220                                 "failed with rc 0x%x\n", xRc);
 221 }
 222
 223 #define REAL_IRQ_TO_BUS(irq)    ((((irq) >> 6) & 0xff) + 1)
 224 #define REAL_IRQ_TO_IDSEL(irq)  ((((irq) >> 3) & 7) + 1)
 225 #define REAL_IRQ_TO_FUNC(irq)   ((irq) & 7)
 226
 227 /*
 228  * This will be called by device drivers (via enable_IRQ)
 229  * to enable INTA in the bridge interrupt status register.
 230  */
 231 static void iSeries_enable_IRQ(unsigned int irq)
 232 {
 233         u32 bus, deviceId, function, mask;
 234         const u32 subBus = 0;
 235         unsigned int rirq = virt_irq_to_real_map[irq];
 236
 237         /* The IRQ has already been locked by the caller */
 238         bus = REAL_IRQ_TO_BUS(rirq);
 239         function = REAL_IRQ_TO_FUNC(rirq);
 240         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 241
 242         /* Unmask secondary INTA */
 243         mask = 0x80000000;
 244         HvCallPci_unmaskInterrupts(bus, subBus, deviceId, mask);
 245 }
 246
 247 /* This is called by iSeries_activate_IRQs */
 248 static unsigned int iSeries_startup_IRQ(unsigned int irq)
 249 {
 250         u32 bus, deviceId, function, mask;
 251         const u32 subBus = 0;
 252         unsigned int rirq = virt_irq_to_real_map[irq];
 253
 254         bus = REAL_IRQ_TO_BUS(rirq);
 255         function = REAL_IRQ_TO_FUNC(rirq);
 256         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 257
 258         /* Link the IRQ number to the bridge */
 259         HvCallXm_connectBusUnit(bus, subBus, deviceId, irq);
 260
 261         /* Unmask bridge interrupts in the FISR */
 262         mask = 0x01010000 << function;
 263         HvCallPci_unmaskFisr(bus, subBus, deviceId, mask);
 264         iSeries_enable_IRQ(irq);
 265         return 0;
 266 }
 267
 268 /*
 269  * This is called out of iSeries_fixup to activate interrupt
 270  * generation for usable slots
 271  */
 272 void __init iSeries_activate_IRQs()
 273 {
 274         int irq;
 275         unsigned long flags;
 276
 277         for_each_irq (irq) {
 278                 irq_desc_t *desc = get_irq_desc(irq);
 279
 280                 if (desc && desc->handler && desc->handler->startup) {
 281                         spin_lock_irqsave(&desc->lock, flags);
 282                         desc->handler->startup(irq);
 283                         spin_unlock_irqrestore(&desc->lock, flags);
 284                 }
 285         }
 286 }
 287
 288 /*  this is not called anywhere currently */
 289 static void iSeries_shutdown_IRQ(unsigned int irq)
 290 {
 291         u32 bus, deviceId, function, mask;
 292         const u32 subBus = 0;
 293         unsigned int rirq = virt_irq_to_real_map[irq];
 294
 295         /* irq should be locked by the caller */
 296         bus = REAL_IRQ_TO_BUS(rirq);
 297         function = REAL_IRQ_TO_FUNC(rirq);
 298         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 299
 300         /* Invalidate the IRQ number in the bridge */
 301         HvCallXm_connectBusUnit(bus, subBus, deviceId, 0);
 302
 303         /* Mask bridge interrupts in the FISR */
 304         mask = 0x01010000 << function;
 305         HvCallPci_maskFisr(bus, subBus, deviceId, mask);
 306 }
 307
 308 /*
 309  * This will be called by device drivers (via disable_IRQ)
 310  * to disable INTA in the bridge interrupt status register.
 311  */
 312 static void iSeries_disable_IRQ(unsigned int irq)
 313 {
 314         u32 bus, deviceId, function, mask;
 315         const u32 subBus = 0;
 316         unsigned int rirq = virt_irq_to_real_map[irq];
 317
 318         /* The IRQ has already been locked by the caller */
 319         bus = REAL_IRQ_TO_BUS(rirq);
 320         function = REAL_IRQ_TO_FUNC(rirq);
 321         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 322
 323         /* Mask secondary INTA   */
 324         mask = 0x80000000;
 325         HvCallPci_maskInterrupts(bus, subBus, deviceId, mask);
 326 }
 327
 328 /*
 329  * Need to define this so ppc_irq_dispatch_handler will NOT call
 330  * enable_IRQ at the end of interrupt handling.  However, this does
 331  * nothing because there is not enough information provided to do
 332  * the EOI HvCall.  This is done by XmPciLpEvent.c
 333  */
 334 static void iSeries_end_IRQ(unsigned int irq)
 335 {
 336 }
 337
 338 static hw_irq_controller iSeries_IRQ_handler = {
 339         .typename = "iSeries irq controller",
 340         .startup = iSeries_startup_IRQ,
 341         .shutdown = iSeries_shutdown_IRQ,
 342         .enable = iSeries_enable_IRQ,
 343         .disable = iSeries_disable_IRQ,
 344         .end = iSeries_end_IRQ
 345 };
 346
 347 /*
 348  * This is called out of iSeries_scan_slot to allocate an IRQ for an EADS slot
 349  * It calculates the irq value for the slot.
 350  * Note that subBusNumber is always 0 (at the moment at least).
 351  */
 352 int __init iSeries_allocate_IRQ(HvBusNumber busNumber,
 353                 HvSubBusNumber subBusNumber, HvAgentId deviceId)
 354 {
 355         unsigned int realirq, virtirq;
 356         u8 idsel = (deviceId >> 4);
 357         u8 function = deviceId & 7;
 358
 359         virtirq = next_virtual_irq++;
 360         realirq = ((busNumber - 1) << 6) + ((idsel - 1) << 3) + function;
 361         virt_irq_to_real_map[virtirq] = realirq;
 362
 363         irq_desc[virtirq].handler = &iSeries_IRQ_handler;
 364         return virtirq;
 365 }
 366
 367 int virt_irq_create_mapping(unsigned int real_irq)
 368 {
 369         BUG(); /* Don't call this on iSeries, yet */
 370
 371         return 0;
 372 }
 373
 374 void virt_irq_init(void)
 375 {
 376         return;
 377 }