git.oblomov.eu Git - linux-2.6/blob - 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/paca.h>
  39 #include <asm/iseries/hv_types.h>
  40 #include <asm/iseries/hv_lp_event.h>
  41 #include <asm/iseries/hv_call_xm.h>
  42 #include <asm/iseries/it_lp_queue.h>
  43
  44 #include "irq.h"
  45 #include "call_pci.h"
  46
  47 #if defined(CONFIG_SMP)
  48 extern void iSeries_smp_message_recv(struct pt_regs *);
  49 #endif
  50
  51 enum pci_event_type {
  52         pe_bus_created          = 0,    /* PHB has been created */
  53         pe_bus_error            = 1,    /* PHB has failed */
  54         pe_bus_failed           = 2,    /* Msg to Secondary, Primary failed bus */
  55         pe_node_failed          = 4,    /* Multi-adapter bridge has failed */
  56         pe_node_recovered       = 5,    /* Multi-adapter bridge has recovered */
  57         pe_bus_recovered        = 12,   /* PHB has been recovered */
  58         pe_unquiese_bus         = 18,   /* Secondary bus unqiescing */
  59         pe_bridge_error         = 21,   /* Bridge Error */
  60         pe_slot_interrupt       = 22    /* Slot interrupt */
  61 };
  62
  63 struct pci_event {
  64         struct HvLpEvent event;
  65         union {
  66                 u64 __align;            /* Align on an 8-byte boundary */
  67                 struct {
  68                         u32             fisr;
  69                         HvBusNumber     bus_number;
  70                         HvSubBusNumber  sub_bus_number;
  71                         HvAgentId       dev_id;
  72                 } slot;
  73                 struct {
  74                         HvBusNumber     bus_number;
  75                         HvSubBusNumber  sub_bus_number;
  76                 } bus;
  77                 struct {
  78                         HvBusNumber     bus_number;
  79                         HvSubBusNumber  sub_bus_number;
  80                         HvAgentId       dev_id;
  81                 } node;
  82         } data;
  83 };
  84
  85 static void int_received(struct pci_event *event, struct pt_regs *regs)
  86 {
  87         int irq;
  88 #ifdef CONFIG_IRQSTACKS
  89         struct thread_info *curtp, *irqtp;
  90 #endif
  91
  92         switch (event->event.xSubtype) {
  93         case pe_slot_interrupt:
  94                 irq = event->event.xCorrelationToken;
  95                 /* Dispatch the interrupt handlers for this irq */
  96 #ifdef CONFIG_IRQSTACKS
  97                 /* Switch to the irq stack to handle this */
  98                 curtp = current_thread_info();
  99                 irqtp = hardirq_ctx[smp_processor_id()];
 100                 if (curtp != irqtp) {
 101                         irqtp->task = curtp->task;
 102                         irqtp->flags = 0;
 103                         call___do_IRQ(irq, regs, irqtp);
 104                         irqtp->task = NULL;
 105                         if (irqtp->flags)
 106                                 set_bits(irqtp->flags, &curtp->flags);
 107                 } else
 108 #endif
 109                         __do_IRQ(irq, regs);
 110                 break;
 111                 /* Ignore error recovery events for now */
 112         case pe_bus_created:
 113                 printk(KERN_INFO "int_received: system bus %d created\n",
 114                         event->data.bus.bus_number);
 115                 break;
 116         case pe_bus_error:
 117         case pe_bus_failed:
 118                 printk(KERN_INFO "int_received: system bus %d failed\n",
 119                         event->data.bus.bus_number);
 120                 break;
 121         case pe_bus_recovered:
 122         case pe_unquiese_bus:
 123                 printk(KERN_INFO "int_received: system bus %d recovered\n",
 124                         event->data.bus.bus_number);
 125                 break;
 126         case pe_node_failed:
 127         case pe_bridge_error:
 128                 printk(KERN_INFO
 129                         "int_received: multi-adapter bridge %d/%d/%d failed\n",
 130                         event->data.node.bus_number,
 131                         event->data.node.sub_bus_number,
 132                         event->data.node.dev_id);
 133                 break;
 134         case pe_node_recovered:
 135                 printk(KERN_INFO
 136                         "int_received: multi-adapter bridge %d/%d/%d recovered\n",
 137                         event->data.node.bus_number,
 138                         event->data.node.sub_bus_number,
 139                         event->data.node.dev_id);
 140                 break;
 141         default:
 142                 printk(KERN_ERR
 143                         "int_received: unrecognized event subtype 0x%x\n",
 144                         event->event.xSubtype);
 145                 break;
 146         }
 147 }
 148
 149 static void pci_event_handler(struct HvLpEvent *event, struct pt_regs *regs)
 150 {
 151         if (event && (event->xType == HvLpEvent_Type_PciIo)) {
 152                 switch (event->xFlags.xFunction) {
 153                 case HvLpEvent_Function_Int:
 154                         int_received((struct pci_event *)event, regs);
 155                         break;
 156                 case HvLpEvent_Function_Ack:
 157                         printk(KERN_ERR
 158                                 "pci_event_handler: unexpected ack received\n");
 159                         break;
 160                 default:
 161                         printk(KERN_ERR
 162                                 "pci_event_handler: unexpected event function %d\n",
 163                                 (int)event->xFlags.xFunction);
 164                         break;
 165                 }
 166         } else if (event)
 167                 printk(KERN_ERR
 168                         "pci_event_handler: Unrecognized PCI event type 0x%x\n",
 169                         (int)event->xType);
 170         else
 171                 printk(KERN_ERR "pci_event_handler: NULL event received\n");
 172 }
 173
 174 /*
 175  * This is called by init_IRQ.  set in ppc_md.init_IRQ by iSeries_setup.c
 176  * It must be called before the bus walk.
 177  */
 178 void __init iSeries_init_IRQ(void)
 179 {
 180         /* Register PCI event handler and open an event path */
 181         int ret;
 182
 183         ret = HvLpEvent_registerHandler(HvLpEvent_Type_PciIo,
 184                         &pci_event_handler);
 185         if (ret == 0) {
 186                 ret = HvLpEvent_openPath(HvLpEvent_Type_PciIo, 0);
 187                 if (ret != 0)
 188                         printk(KERN_ERR "iseries_init_IRQ: open event path "
 189                                         "failed with rc 0x%x\n", ret);
 190         } else
 191                 printk(KERN_ERR "iseries_init_IRQ: register handler "
 192                                 "failed with rc 0x%x\n", ret);
 193 }
 194
 195 #define REAL_IRQ_TO_SUBBUS(irq) (((irq) >> 14) & 0xff)
 196 #define REAL_IRQ_TO_BUS(irq)    ((((irq) >> 6) & 0xff) + 1)
 197 #define REAL_IRQ_TO_IDSEL(irq)  ((((irq) >> 3) & 7) + 1)
 198 #define REAL_IRQ_TO_FUNC(irq)   ((irq) & 7)
 199
 200 /*
 201  * This will be called by device drivers (via enable_IRQ)
 202  * to enable INTA in the bridge interrupt status register.
 203  */
 204 static void iseries_enable_IRQ(unsigned int irq)
 205 {
 206         u32 bus, dev_id, function, mask;
 207         const u32 sub_bus = 0;
 208         unsigned int rirq = virt_irq_to_real_map[irq];
 209
 210         /* The IRQ has already been locked by the caller */
 211         bus = REAL_IRQ_TO_BUS(rirq);
 212         function = REAL_IRQ_TO_FUNC(rirq);
 213         dev_id = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 214
 215         /* Unmask secondary INTA */
 216         mask = 0x80000000;
 217         HvCallPci_unmaskInterrupts(bus, sub_bus, dev_id, mask);
 218 }
 219
 220 /* This is called by iseries_activate_IRQs */
 221 static unsigned int iseries_startup_IRQ(unsigned int irq)
 222 {
 223         u32 bus, dev_id, function, mask;
 224         const u32 sub_bus = 0;
 225         unsigned int rirq = virt_irq_to_real_map[irq];
 226
 227         bus = REAL_IRQ_TO_BUS(rirq);
 228         function = REAL_IRQ_TO_FUNC(rirq);
 229         dev_id = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 230
 231         /* Link the IRQ number to the bridge */
 232         HvCallXm_connectBusUnit(bus, sub_bus, dev_id, irq);
 233
 234         /* Unmask bridge interrupts in the FISR */
 235         mask = 0x01010000 << function;
 236         HvCallPci_unmaskFisr(bus, sub_bus, dev_id, mask);
 237         iseries_enable_IRQ(irq);
 238         return 0;
 239 }
 240
 241 /*
 242  * This is called out of iSeries_fixup to activate interrupt
 243  * generation for usable slots
 244  */
 245 void __init iSeries_activate_IRQs()
 246 {
 247         int irq;
 248         unsigned long flags;
 249
 250         for_each_irq (irq) {
 251                 irq_desc_t *desc = get_irq_desc(irq);
 252
 253                 if (desc && desc->handler && desc->handler->startup) {
 254                         spin_lock_irqsave(&desc->lock, flags);
 255                         desc->handler->startup(irq);
 256                         spin_unlock_irqrestore(&desc->lock, flags);
 257                 }
 258         }
 259 }
 260
 261 /*  this is not called anywhere currently */
 262 static void iseries_shutdown_IRQ(unsigned int irq)
 263 {
 264         u32 bus, dev_id, function, mask;
 265         const u32 sub_bus = 0;
 266         unsigned int rirq = virt_irq_to_real_map[irq];
 267
 268         /* irq should be locked by the caller */
 269         bus = REAL_IRQ_TO_BUS(rirq);
 270         function = REAL_IRQ_TO_FUNC(rirq);
 271         dev_id = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 272
 273         /* Invalidate the IRQ number in the bridge */
 274         HvCallXm_connectBusUnit(bus, sub_bus, dev_id, 0);
 275
 276         /* Mask bridge interrupts in the FISR */
 277         mask = 0x01010000 << function;
 278         HvCallPci_maskFisr(bus, sub_bus, dev_id, mask);
 279 }
 280
 281 /*
 282  * This will be called by device drivers (via disable_IRQ)
 283  * to disable INTA in the bridge interrupt status register.
 284  */
 285 static void iseries_disable_IRQ(unsigned int irq)
 286 {
 287         u32 bus, dev_id, function, mask;
 288         const u32 sub_bus = 0;
 289         unsigned int rirq = virt_irq_to_real_map[irq];
 290
 291         /* The IRQ has already been locked by the caller */
 292         bus = REAL_IRQ_TO_BUS(rirq);
 293         function = REAL_IRQ_TO_FUNC(rirq);
 294         dev_id = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
 295
 296         /* Mask secondary INTA   */
 297         mask = 0x80000000;
 298         HvCallPci_maskInterrupts(bus, sub_bus, dev_id, mask);
 299 }
 300
 301 static void iseries_end_IRQ(unsigned int irq)
 302 {
 303         unsigned int rirq = virt_irq_to_real_map[irq];
 304
 305         HvCallPci_eoi(REAL_IRQ_TO_BUS(rirq), REAL_IRQ_TO_SUBBUS(rirq),
 306                 (REAL_IRQ_TO_IDSEL(rirq) << 4) + REAL_IRQ_TO_FUNC(rirq));
 307 }
 308
 309 static hw_irq_controller iSeries_IRQ_handler = {
 310         .typename = "iSeries irq controller",
 311         .startup = iseries_startup_IRQ,
 312         .shutdown = iseries_shutdown_IRQ,
 313         .enable = iseries_enable_IRQ,
 314         .disable = iseries_disable_IRQ,
 315         .end = iseries_end_IRQ
 316 };
 317
 318 /*
 319  * This is called out of iSeries_scan_slot to allocate an IRQ for an EADS slot
 320  * It calculates the irq value for the slot.
 321  * Note that sub_bus is always 0 (at the moment at least).
 322  */
 323 int __init iSeries_allocate_IRQ(HvBusNumber bus,
 324                 HvSubBusNumber sub_bus, HvAgentId dev_id)
 325 {
 326         int virtirq;
 327         unsigned int realirq;
 328         u8 idsel = (dev_id >> 4);
 329         u8 function = dev_id & 7;
 330
 331         realirq = (((((sub_bus << 8) + (bus - 1)) << 3) + (idsel - 1)) << 3)
 332                 + function;
 333         virtirq = virt_irq_create_mapping(realirq);
 334
 335         irq_desc[virtirq].handler = &iSeries_IRQ_handler;
 336         return virtirq;
 337 }
 338
 339 /*
 340  * Get the next pending IRQ.
 341  */
 342 int iSeries_get_irq(struct pt_regs *regs)
 343 {
 344         struct paca_struct *lpaca;
 345
 346         lpaca = get_paca();
 347 #ifdef CONFIG_SMP
 348         if (lpaca->lppaca.int_dword.fields.ipi_cnt) {
 349                 lpaca->lppaca.int_dword.fields.ipi_cnt = 0;
 350                 iSeries_smp_message_recv(regs);
 351         }
 352 #endif /* CONFIG_SMP */
 353         if (hvlpevent_is_pending())
 354                 process_hvlpevents(regs);
 355
 356         /* -2 means ignore this interrupt */
 357         return -2;
 358 }