arch/ppc64/kernel/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 #include <asm/iSeries/iSeries_irq.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
 107         ++Pci_Interrupt_Count;
 108
 109         switch (eventParm->hvLpEvent.xSubtype) {
 110         case XmPciLpEvent_SlotInterrupt:
 111                 irq = eventParm->hvLpEvent.xCorrelationToken;
 112                 /* Dispatch the interrupt handlers for this irq */
 113                 ppc_irq_dispatch_handler(regsParm, irq);
 114                 HvCallPci_eoi(eventParm->eventData.slotInterrupt.busNumber,
 115                         eventParm->eventData.slotInterrupt.subBusNumber,
 116                         eventParm->eventData.slotInterrupt.deviceId);
 117                 break;
 118                 /* Ignore error recovery events for now */
 119         case XmPciLpEvent_BusCreated:
 120                 printk(KERN_INFO "intReceived: system bus %d created\n",
 121                         eventParm->eventData.busCreated.busNumber);
 122                 break;
 123         case XmPciLpEvent_BusError:
 124         case XmPciLpEvent_BusFailed:
 125                 printk(KERN_INFO "intReceived: system bus %d failed\n",
 126                         eventParm->eventData.busFailed.busNumber);
 127                 break;
 128         case XmPciLpEvent_BusRecovered:
 129         case XmPciLpEvent_UnQuiesceBus:
 130                 printk(KERN_INFO "intReceived: system bus %d recovered\n",
 131                         eventParm->eventData.busRecovered.busNumber);
 132                 break;
 133         case XmPciLpEvent_NodeFailed:
 134         case XmPciLpEvent_BridgeError:
 135                 printk(KERN_INFO
 136                         "intReceived: multi-adapter bridge %d/%d/%d failed\n",
 137                         eventParm->eventData.nodeFailed.busNumber,
 138                         eventParm->eventData.nodeFailed.subBusNumber,
 139                         eventParm->eventData.nodeFailed.deviceId);
 140                 break;
 141         case XmPciLpEvent_NodeRecovered:
 142                 printk(KERN_INFO
 143                         "intReceived: multi-adapter bridge %d/%d/%d recovered\n",
 144                         eventParm->eventData.nodeRecovered.busNumber,
 145                         eventParm->eventData.nodeRecovered.subBusNumber,
 146                         eventParm->eventData.nodeRecovered.deviceId);
 147                 break;
 148         default:
 149                 printk(KERN_ERR
 150                         "intReceived: unrecognized event subtype 0x%x\n",
 151                         eventParm->hvLpEvent.xSubtype);
 152                 break;
 153         }
 154 }
 155
 156 static void XmPciLpEvent_handler(struct HvLpEvent *eventParm,
 157                 struct pt_regs *regsParm)
 158 {
 159 #ifdef CONFIG_PCI
 160         ++Pci_Event_Count;
 161
 162         if (eventParm && (eventParm->xType == HvLpEvent_Type_PciIo)) {
 163                 switch (eventParm->xFlags.xFunction) {
 164                 case HvLpEvent_Function_Int:
 165                         intReceived((struct XmPciLpEvent *)eventParm, regsParm);
 166                         break;
 167                 case HvLpEvent_Function_Ack:
 168                         printk(KERN_ERR
 169                                 "XmPciLpEvent_handler: unexpected ack received\n");
 170                         break;
 171                 default:
 172                         printk(KERN_ERR
 173                                 "XmPciLpEvent_handler: unexpected event function %d\n",
 174                                 (int)eventParm->xFlags.xFunction);
 175                         break;
 176                 }
 177         } else if (eventParm)
 178                 printk(KERN_ERR
 179                         "XmPciLpEvent_handler: Unrecognized PCI event type 0x%x\n",
 180                         (int)eventParm->xType);
 181         else
 182                 printk(KERN_ERR "XmPciLpEvent_handler: NULL event received\n");
 183 #endif
 184 }
 185
 186 /*
 187  * This is called by init_IRQ.  set in ppc_md.init_IRQ by iSeries_setup.c
 188  * It must be called before the bus walk.
 189  */
 190 void __init iSeries_init_IRQ(void)
 191 {
 192         /* Register PCI event handler and open an event path */
 193         int xRc;
 194
 195         xRc = HvLpEvent_registerHandler(HvLpEvent_Type_PciIo,
 196                         &XmPciLpEvent_handler);
 197         if (xRc == 0) {
 198                 xRc = HvLpEvent_openPath(HvLpEvent_Type_PciIo, 0);
 199                 if (xRc != 0)
 200                         printk(KERN_ERR "iSeries_init_IRQ: open event path "
 201                                         "failed with rc 0x%x\n", xRc);
 202         } else
 203                 printk(KERN_ERR "iSeries_init_IRQ: register handler "
 204                                 "failed with rc 0x%x\n", xRc);
 205 }
 206
 207 #define REAL_IRQ_TO_BUS(irq)    ((((irq) >> 6) & 0xff) + 1)
 208 #define REAL_IRQ_TO_IDSEL(irq)  ((((irq) >> 3) & 7) + 1)
 209 #define REAL_IRQ_TO_FUNC(irq)   ((irq) & 7)
 210
 211 /*
 212  * This will be called by device drivers (via enable_IRQ)
 213  * to enable INTA in the bridge interrupt status register.
 214  */
 215 static void iSeries_enable_IRQ(unsigned int irq)
 216 {
 217         u32 bus, deviceId, function, mask;
 218         const u32 subBus = 0;
 219         unsigned int rirq = virt_irq_to_real_map[irq];
 220
 221         /* The IRQ has already been locked by the caller */
 222         bus = REAL_IRQ_TO_BUS(rirq);
 223         function = REAL_IRQ_TO_FUNC(rirq);
 224         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 225
 226         /* Unmask secondary INTA */
 227         mask = 0x80000000;
 228         HvCallPci_unmaskInterrupts(bus, subBus, deviceId, mask);
 229         PPCDBG(PPCDBG_BUSWALK, "iSeries_enable_IRQ 0x%02X.%02X.%02X 0x%04X\n",
 230                         bus, subBus, deviceId, irq);
 231 }
 232
 233 /* This is called by iSeries_activate_IRQs */
 234 static unsigned int iSeries_startup_IRQ(unsigned int irq)
 235 {
 236         u32 bus, deviceId, function, mask;
 237         const u32 subBus = 0;
 238         unsigned int rirq = virt_irq_to_real_map[irq];
 239
 240         bus = REAL_IRQ_TO_BUS(rirq);
 241         function = REAL_IRQ_TO_FUNC(rirq);
 242         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 243
 244         /* Link the IRQ number to the bridge */
 245         HvCallXm_connectBusUnit(bus, subBus, deviceId, irq);
 246
 247         /* Unmask bridge interrupts in the FISR */
 248         mask = 0x01010000 << function;
 249         HvCallPci_unmaskFisr(bus, subBus, deviceId, mask);
 250         iSeries_enable_IRQ(irq);
 251         return 0;
 252 }
 253
 254 /*
 255  * This is called out of iSeries_fixup to activate interrupt
 256  * generation for usable slots
 257  */
 258 void __init iSeries_activate_IRQs()
 259 {
 260         int irq;
 261         unsigned long flags;
 262
 263         for_each_irq (irq) {
 264                 irq_desc_t *desc = get_irq_desc(irq);
 265
 266                 if (desc && desc->handler && desc->handler->startup) {
 267                         spin_lock_irqsave(&desc->lock, flags);
 268                         desc->handler->startup(irq);
 269                         spin_unlock_irqrestore(&desc->lock, flags);
 270                 }
 271         }
 272 }
 273
 274 /*  this is not called anywhere currently */
 275 static void iSeries_shutdown_IRQ(unsigned int irq)
 276 {
 277         u32 bus, deviceId, function, mask;
 278         const u32 subBus = 0;
 279         unsigned int rirq = virt_irq_to_real_map[irq];
 280
 281         /* irq should be locked by the caller */
 282         bus = REAL_IRQ_TO_BUS(rirq);
 283         function = REAL_IRQ_TO_FUNC(rirq);
 284         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 285
 286         /* Invalidate the IRQ number in the bridge */
 287         HvCallXm_connectBusUnit(bus, subBus, deviceId, 0);
 288
 289         /* Mask bridge interrupts in the FISR */
 290         mask = 0x01010000 << function;
 291         HvCallPci_maskFisr(bus, subBus, deviceId, mask);
 292 }
 293
 294 /*
 295  * This will be called by device drivers (via disable_IRQ)
 296  * to disable INTA in the bridge interrupt status register.
 297  */
 298 static void iSeries_disable_IRQ(unsigned int irq)
 299 {
 300         u32 bus, deviceId, function, mask;
 301         const u32 subBus = 0;
 302         unsigned int rirq = virt_irq_to_real_map[irq];
 303
 304         /* The IRQ has already been locked by the caller */
 305         bus = REAL_IRQ_TO_BUS(rirq);
 306         function = REAL_IRQ_TO_FUNC(rirq);
 307         deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 308
 309         /* Mask secondary INTA   */
 310         mask = 0x80000000;
 311         HvCallPci_maskInterrupts(bus, subBus, deviceId, mask);
 312         PPCDBG(PPCDBG_BUSWALK, "iSeries_disable_IRQ 0x%02X.%02X.%02X 0x%04X\n",
 313                         bus, subBus, deviceId, irq);
 314 }
 315
 316 /*
 317  * Need to define this so ppc_irq_dispatch_handler will NOT call
 318  * enable_IRQ at the end of interrupt handling.  However, this does
 319  * nothing because there is not enough information provided to do
 320  * the EOI HvCall.  This is done by XmPciLpEvent.c
 321  */
 322 static void iSeries_end_IRQ(unsigned int irq)
 323 {
 324 }
 325
 326 static hw_irq_controller iSeries_IRQ_handler = {
 327         .typename = "iSeries irq controller",
 328         .startup = iSeries_startup_IRQ,
 329         .shutdown = iSeries_shutdown_IRQ,
 330         .enable = iSeries_enable_IRQ,
 331         .disable = iSeries_disable_IRQ,
 332         .end = iSeries_end_IRQ
 333 };
 334
 335 /*
 336  * This is called out of iSeries_scan_slot to allocate an IRQ for an EADS slot
 337  * It calculates the irq value for the slot.
 338  * Note that subBusNumber is always 0 (at the moment at least).
 339  */
 340 int __init iSeries_allocate_IRQ(HvBusNumber busNumber,
 341                 HvSubBusNumber subBusNumber, HvAgentId deviceId)
 342 {
 343         unsigned int realirq, virtirq;
 344         u8 idsel = (deviceId >> 4);
 345         u8 function = deviceId & 7;
 346
 347         virtirq = next_virtual_irq++;
 348         realirq = ((busNumber - 1) << 6) + ((idsel - 1) << 3) + function;
 349         virt_irq_to_real_map[virtirq] = realirq;
 350
 351         irq_desc[virtirq].handler = &iSeries_IRQ_handler;
 352         return virtirq;
 353 }