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