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/ppcdebug.h>
  39 #include <asm/iSeries/HvTypes.h>
  40 #include <asm/iSeries/HvLpEvent.h>
  41 #include <asm/iSeries/HvCallPci.h>
  42 #include <asm/iSeries/HvCallXm.h>
  43
  44 #include "irq.h"
  45
  46 /* This maps virtual irq numbers to real irqs */
  47 unsigned int virt_irq_to_real_map[NR_IRQS];
  48
  49 /* The next available virtual irq number */
  50 /* Note: the pcnet32 driver assumes irq numbers < 2 aren't valid. :( */
  51 static int next_virtual_irq = 2;
  52
  53 static long Pci_Interrupt_Count;
  54 static long Pci_Event_Count;
  55
  56 enum XmPciLpEvent_Subtype {
  57         XmPciLpEvent_BusCreated         = 0,    // PHB has been created
  58         XmPciLpEvent_BusError           = 1,    // PHB has failed
  59         XmPciLpEvent_BusFailed          = 2,    // Msg to Secondary, Primary failed bus
  60         XmPciLpEvent_NodeFailed         = 4,    // Multi-adapter bridge has failed
  61         XmPciLpEvent_NodeRecovered      = 5,    // Multi-adapter bridge has recovered
  62         XmPciLpEvent_BusRecovered       = 12,   // PHB has been recovered
  63         XmPciLpEvent_UnQuiesceBus       = 18,   // Secondary bus unqiescing
  64         XmPciLpEvent_BridgeError        = 21,   // Bridge Error
  65         XmPciLpEvent_SlotInterrupt      = 22    // Slot interrupt
  66 };
  67
  68 struct XmPciLpEvent_BusInterrupt {
  69         HvBusNumber     busNumber;
  70         HvSubBusNumber  subBusNumber;
  71 };
  72
  73 struct XmPciLpEvent_NodeInterrupt {
  74         HvBusNumber     busNumber;
  75         HvSubBusNumber  subBusNumber;
  76         HvAgentId       deviceId;
  77 };
  78
  79 struct XmPciLpEvent {
  80         struct HvLpEvent hvLpEvent;
  81
  82         union {
  83                 u64 alignData;                  // Align on an 8-byte boundary
  84
  85                 struct {
  86                         u32             fisr;
  87                         HvBusNumber     busNumber;
  88                         HvSubBusNumber  subBusNumber;
  89                         HvAgentId       deviceId;
  90                 } slotInterrupt;
  91
  92                 struct XmPciLpEvent_BusInterrupt busFailed;
  93                 struct XmPciLpEvent_BusInterrupt busRecovered;
  94                 struct XmPciLpEvent_BusInterrupt busCreated;
  95
  96                 struct XmPciLpEvent_NodeInterrupt nodeFailed;
  97                 struct XmPciLpEvent_NodeInterrupt nodeRecovered;
  98
  99         } eventData;
 100
 101 };
 102
 103 static void intReceived(struct XmPciLpEvent *eventParm,
 104                 struct pt_regs *regsParm)
 105 {
 106         int irq;
 107
 108         ++Pci_Interrupt_Count;
 109
 110         switch (eventParm->hvLpEvent.xSubtype) {
 111         case XmPciLpEvent_SlotInterrupt:
 112                 irq = eventParm->hvLpEvent.xCorrelationToken;
 113                 /* Dispatch the interrupt handlers for this irq */
 114                 ppc_irq_dispatch_handler(regsParm, irq);
 115                 HvCallPci_eoi(eventParm->eventData.slotInterrupt.busNumber,
 116                         eventParm->eventData.slotInterrupt.subBusNumber,
 117                         eventParm->eventData.slotInterrupt.deviceId);
 118                 break;
 119                 /* Ignore error recovery events for now */
 120         case XmPciLpEvent_BusCreated:
 121                 printk(KERN_INFO "intReceived: system bus %d created\n",
 122                         eventParm->eventData.busCreated.busNumber);
 123                 break;
 124         case XmPciLpEvent_BusError:
 125         case XmPciLpEvent_BusFailed:
 126                 printk(KERN_INFO "intReceived: system bus %d failed\n",
 127                         eventParm->eventData.busFailed.busNumber);
 128                 break;
 129         case XmPciLpEvent_BusRecovered:
 130         case XmPciLpEvent_UnQuiesceBus:
 131                 printk(KERN_INFO "intReceived: system bus %d recovered\n",
 132                         eventParm->eventData.busRecovered.busNumber);
 133                 break;
 134         case XmPciLpEvent_NodeFailed:
 135         case XmPciLpEvent_BridgeError:
 136                 printk(KERN_INFO
 137                         "intReceived: multi-adapter bridge %d/%d/%d failed\n",
 138                         eventParm->eventData.nodeFailed.busNumber,
 139                         eventParm->eventData.nodeFailed.subBusNumber,
 140                         eventParm->eventData.nodeFailed.deviceId);
 141                 break;
 142         case XmPciLpEvent_NodeRecovered:
 143                 printk(KERN_INFO
 144                         "intReceived: multi-adapter bridge %d/%d/%d recovered\n",
 145                         eventParm->eventData.nodeRecovered.busNumber,
 146                         eventParm->eventData.nodeRecovered.subBusNumber,
 147                         eventParm->eventData.nodeRecovered.deviceId);
 148                 break;
 149         default:
 150                 printk(KERN_ERR
 151                         "intReceived: unrecognized event subtype 0x%x\n",
 152                         eventParm->hvLpEvent.xSubtype);
 153                 break;
 154         }
 155 }
 156
 157 static void XmPciLpEvent_handler(struct HvLpEvent *eventParm,
 158                 struct pt_regs *regsParm)
 159 {
 160 #ifdef CONFIG_PCI
 161         ++Pci_Event_Count;
 162
 163         if (eventParm && (eventParm->xType == HvLpEvent_Type_PciIo)) {
 164                 switch (eventParm->xFlags.xFunction) {
 165                 case HvLpEvent_Function_Int:
 166                         intReceived((struct XmPciLpEvent *)eventParm, regsParm);
 167                         break;
 168                 case HvLpEvent_Function_Ack:
 169                         printk(KERN_ERR
 170                                 "XmPciLpEvent_handler: unexpected ack received\n");
 171                         break;
 172                 default:
 173                         printk(KERN_ERR
 174                                 "XmPciLpEvent_handler: unexpected event function %d\n",
 175                                 (int)eventParm->xFlags.xFunction);
 176                         break;
 177                 }
 178         } else if (eventParm)
 179                 printk(KERN_ERR
 180                         "XmPciLpEvent_handler: Unrecognized PCI event type 0x%x\n",
 181                         (int)eventParm->xType);
 182         else
 183                 printk(KERN_ERR "XmPciLpEvent_handler: NULL event received\n");
 184 #endif
 185 }
 186
 187 /*
 188  * This is called by init_IRQ.  set in ppc_md.init_IRQ by iSeries_setup.c
 189  * It must be called before the bus walk.
 190  */
 191 void __init iSeries_init_IRQ(void)
 192 {
 193         /* Register PCI event handler and open an event path */
 194         int xRc;
 195
 196         xRc = HvLpEvent_registerHandler(HvLpEvent_Type_PciIo,
 197                         &XmPciLpEvent_handler);
 198         if (xRc == 0) {
 199                 xRc = HvLpEvent_openPath(HvLpEvent_Type_PciIo, 0);
 200                 if (xRc != 0)
 201                         printk(KERN_ERR "iSeries_init_IRQ: open event path "
 202                                         "failed with rc 0x%x\n", xRc);
 203         } else
 204                 printk(KERN_ERR "iSeries_init_IRQ: register handler "
 205                                 "failed with rc 0x%x\n", xRc);
 206 }
 207
 208 #define REAL_IRQ_TO_BUS(irq)    ((((irq) >> 6) & 0xff) + 1)
 209 #define REAL_IRQ_TO_IDSEL(irq)  ((((irq) >> 3) & 7) + 1)
 210 #define REAL_IRQ_TO_FUNC(irq)   ((irq) & 7)
 211
 212 /*
 213  * This will be called by device drivers (via enable_IRQ)
 214  * to enable INTA in the bridge interrupt status register.
 215  */
 216 static void iSeries_enable_IRQ(unsigned int irq)
 217 {
 218         u32 bus, deviceId, function, mask;
 219         const u32 subBus = 0;
 220         unsigned int rirq = virt_irq_to_real_map[irq];
 221
 222         /* The IRQ has already been locked by the caller */
 223         bus = REAL_IRQ_TO_BUS(rirq);
 224         function = REAL_IRQ_TO_FUNC(rirq);
 225         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 226
 227         /* Unmask secondary INTA */
 228         mask = 0x80000000;
 229         HvCallPci_unmaskInterrupts(bus, subBus, deviceId, mask);
 230         PPCDBG(PPCDBG_BUSWALK, "iSeries_enable_IRQ 0x%02X.%02X.%02X 0x%04X\n",
 231                         bus, subBus, deviceId, irq);
 232 }
 233
 234 /* This is called by iSeries_activate_IRQs */
 235 static unsigned int iSeries_startup_IRQ(unsigned int irq)
 236 {
 237         u32 bus, deviceId, function, mask;
 238         const u32 subBus = 0;
 239         unsigned int rirq = virt_irq_to_real_map[irq];
 240
 241         bus = REAL_IRQ_TO_BUS(rirq);
 242         function = REAL_IRQ_TO_FUNC(rirq);
 243         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 244
 245         /* Link the IRQ number to the bridge */
 246         HvCallXm_connectBusUnit(bus, subBus, deviceId, irq);
 247
 248         /* Unmask bridge interrupts in the FISR */
 249         mask = 0x01010000 << function;
 250         HvCallPci_unmaskFisr(bus, subBus, deviceId, mask);
 251         iSeries_enable_IRQ(irq);
 252         return 0;
 253 }
 254
 255 /*
 256  * This is called out of iSeries_fixup to activate interrupt
 257  * generation for usable slots
 258  */
 259 void __init iSeries_activate_IRQs()
 260 {
 261         int irq;
 262         unsigned long flags;
 263
 264         for_each_irq (irq) {
 265                 irq_desc_t *desc = get_irq_desc(irq);
 266
 267                 if (desc && desc->handler && desc->handler->startup) {
 268                         spin_lock_irqsave(&desc->lock, flags);
 269                         desc->handler->startup(irq);
 270                         spin_unlock_irqrestore(&desc->lock, flags);
 271                 }
 272         }
 273 }
 274
 275 /*  this is not called anywhere currently */
 276 static void iSeries_shutdown_IRQ(unsigned int irq)
 277 {
 278         u32 bus, deviceId, function, mask;
 279         const u32 subBus = 0;
 280         unsigned int rirq = virt_irq_to_real_map[irq];
 281
 282         /* irq should be locked by the caller */
 283         bus = REAL_IRQ_TO_BUS(rirq);
 284         function = REAL_IRQ_TO_FUNC(rirq);
 285         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 286
 287         /* Invalidate the IRQ number in the bridge */
 288         HvCallXm_connectBusUnit(bus, subBus, deviceId, 0);
 289
 290         /* Mask bridge interrupts in the FISR */
 291         mask = 0x01010000 << function;
 292         HvCallPci_maskFisr(bus, subBus, deviceId, mask);
 293 }
 294
 295 /*
 296  * This will be called by device drivers (via disable_IRQ)
 297  * to disable INTA in the bridge interrupt status register.
 298  */
 299 static void iSeries_disable_IRQ(unsigned int irq)
 300 {
 301         u32 bus, deviceId, function, mask;
 302         const u32 subBus = 0;
 303         unsigned int rirq = virt_irq_to_real_map[irq];
 304
 305         /* The IRQ has already been locked by the caller */
 306         bus = REAL_IRQ_TO_BUS(rirq);
 307         function = REAL_IRQ_TO_FUNC(rirq);
 308         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 309
 310         /* Mask secondary INTA   */
 311         mask = 0x80000000;
 312         HvCallPci_maskInterrupts(bus, subBus, deviceId, mask);
 313         PPCDBG(PPCDBG_BUSWALK, "iSeries_disable_IRQ 0x%02X.%02X.%02X 0x%04X\n",
 314                         bus, subBus, deviceId, irq);
 315 }
 316
 317 /*
 318  * Need to define this so ppc_irq_dispatch_handler will NOT call
 319  * enable_IRQ at the end of interrupt handling.  However, this does
 320  * nothing because there is not enough information provided to do
 321  * the EOI HvCall.  This is done by XmPciLpEvent.c
 322  */
 323 static void iSeries_end_IRQ(unsigned int irq)
 324 {
 325 }
 326
 327 static hw_irq_controller iSeries_IRQ_handler = {
 328         .typename = "iSeries irq controller",
 329         .startup = iSeries_startup_IRQ,
 330         .shutdown = iSeries_shutdown_IRQ,
 331         .enable = iSeries_enable_IRQ,
 332         .disable = iSeries_disable_IRQ,
 333         .end = iSeries_end_IRQ
 334 };
 335
 336 /*
 337  * This is called out of iSeries_scan_slot to allocate an IRQ for an EADS slot
 338  * It calculates the irq value for the slot.
 339  * Note that subBusNumber is always 0 (at the moment at least).
 340  */
 341 int __init iSeries_allocate_IRQ(HvBusNumber busNumber,
 342                 HvSubBusNumber subBusNumber, HvAgentId deviceId)
 343 {
 344         unsigned int realirq, virtirq;
 345         u8 idsel = (deviceId >> 4);
 346         u8 function = deviceId & 7;
 347
 348         virtirq = next_virtual_irq++;
 349         realirq = ((busNumber - 1) << 6) + ((idsel - 1) << 3) + function;
 350         virt_irq_to_real_map[virtirq] = realirq;
 351
 352         irq_desc[virtirq].handler = &iSeries_IRQ_handler;
 353         return virtirq;
 354 }
 355
 356 int virt_irq_create_mapping(unsigned int real_irq)
 357 {
 358         BUG(); /* Don't call this on iSeries, yet */
 359
 360         return 0;
 361 }
 362
 363 void virt_irq_init(void)
 364 {
 365         return;
 366 }