arch/ia64/sn/kernel/irq.c

   1 /*
   2  * Platform dependent support for SGI SN
   3  *
   4  * This file is subject to the terms and conditions of the GNU General Public
   5  * License.  See the file "COPYING" in the main directory of this archive
   6  * for more details.
   7  *
   8  * Copyright (c) 2000-2008 Silicon Graphics, Inc.  All Rights Reserved.
   9  */
  10
  11 #include <linux/irq.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/init.h>
  14 #include <linux/rculist.h>
  15 #include <linux/slab.h>
  16 #include <asm/sn/addrs.h>
  17 #include <asm/sn/arch.h>
  18 #include <asm/sn/intr.h>
  19 #include <asm/sn/pcibr_provider.h>
  20 #include <asm/sn/pcibus_provider_defs.h>
  21 #include <asm/sn/pcidev.h>
  22 #include <asm/sn/shub_mmr.h>
  23 #include <asm/sn/sn_sal.h>
  24 #include <asm/sn/sn_feature_sets.h>
  25
  26 static void register_intr_pda(struct sn_irq_info *sn_irq_info);
  27 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info);
  28
  29 extern int sn_ioif_inited;
  30 struct list_head **sn_irq_lh;
  31 static DEFINE_SPINLOCK(sn_irq_info_lock); /* non-IRQ lock */
  32
  33 u64 sn_intr_alloc(nasid_t local_nasid, int local_widget,
  34                                      struct sn_irq_info *sn_irq_info,
  35                                      int req_irq, nasid_t req_nasid,
  36                                      int req_slice)
  37 {
  38         struct ia64_sal_retval ret_stuff;
  39         ret_stuff.status = 0;
  40         ret_stuff.v0 = 0;
  41
  42         SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
  43                         (u64) SAL_INTR_ALLOC, (u64) local_nasid,
  44                         (u64) local_widget, __pa(sn_irq_info), (u64) req_irq,
  45                         (u64) req_nasid, (u64) req_slice);
  46
  47         return ret_stuff.status;
  48 }
  49
  50 void sn_intr_free(nasid_t local_nasid, int local_widget,
  51                                 struct sn_irq_info *sn_irq_info)
  52 {
  53         struct ia64_sal_retval ret_stuff;
  54         ret_stuff.status = 0;
  55         ret_stuff.v0 = 0;
  56
  57         SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
  58                         (u64) SAL_INTR_FREE, (u64) local_nasid,
  59                         (u64) local_widget, (u64) sn_irq_info->irq_irq,
  60                         (u64) sn_irq_info->irq_cookie, 0, 0);
  61 }
  62
  63 u64 sn_intr_redirect(nasid_t local_nasid, int local_widget,
  64                       struct sn_irq_info *sn_irq_info,
  65                       nasid_t req_nasid, int req_slice)
  66 {
  67         struct ia64_sal_retval ret_stuff;
  68         ret_stuff.status = 0;
  69         ret_stuff.v0 = 0;
  70
  71         SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
  72                         (u64) SAL_INTR_REDIRECT, (u64) local_nasid,
  73                         (u64) local_widget, __pa(sn_irq_info),
  74                         (u64) req_nasid, (u64) req_slice, 0);
  75
  76         return ret_stuff.status;
  77 }
  78
  79 static unsigned int sn_startup_irq(struct irq_data *data)
  80 {
  81         return 0;
  82 }
  83
  84 static void sn_shutdown_irq(struct irq_data *data)
  85 {
  86 }
  87
  88 extern void ia64_mca_register_cpev(int);
  89
  90 static void sn_disable_irq(struct irq_data *data)
  91 {
  92         if (data->irq == local_vector_to_irq(IA64_CPE_VECTOR))
  93                 ia64_mca_register_cpev(0);
  94 }
  95
  96 static void sn_enable_irq(struct irq_data *data)
  97 {
  98         if (data->irq == local_vector_to_irq(IA64_CPE_VECTOR))
  99                 ia64_mca_register_cpev(data->irq);
 100 }
 101
 102 static void sn_ack_irq(struct irq_data *data)
 103 {
 104         u64 event_occurred, mask;
 105         unsigned int irq = data->irq & 0xff;
 106
 107         event_occurred = HUB_L((u64*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED));
 108         mask = event_occurred & SH_ALL_INT_MASK;
 109         HUB_S((u64*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS), mask);
 110         __set_bit(irq, (volatile void *)pda->sn_in_service_ivecs);
 111
 112         irq_move_irq(data);
 113 }
 114
 115 struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info,
 116                                        nasid_t nasid, int slice)
 117 {
 118         int vector;
 119         int cpuid;
 120 #ifdef CONFIG_SMP
 121         int cpuphys;
 122 #endif
 123         int64_t bridge;
 124         int local_widget, status;
 125         nasid_t local_nasid;
 126         struct sn_irq_info *new_irq_info;
 127         struct sn_pcibus_provider *pci_provider;
 128
 129         bridge = (u64) sn_irq_info->irq_bridge;
 130         if (!bridge) {
 131                 return NULL; /* irq is not a device interrupt */
 132         }
 133
 134         local_nasid = NASID_GET(bridge);
 135
 136         if (local_nasid & 1)
 137                 local_widget = TIO_SWIN_WIDGETNUM(bridge);
 138         else
 139                 local_widget = SWIN_WIDGETNUM(bridge);
 140         vector = sn_irq_info->irq_irq;
 141
 142         /* Make use of SAL_INTR_REDIRECT if PROM supports it */
 143         status = sn_intr_redirect(local_nasid, local_widget, sn_irq_info, nasid, slice);
 144         if (!status) {
 145                 new_irq_info = sn_irq_info;
 146                 goto finish_up;
 147         }
 148
 149         /*
 150          * PROM does not support SAL_INTR_REDIRECT, or it failed.
 151          * Revert to old method.
 152          */
 153         new_irq_info = kmalloc(sizeof(struct sn_irq_info), GFP_ATOMIC);
 154         if (new_irq_info == NULL)
 155                 return NULL;
 156
 157         memcpy(new_irq_info, sn_irq_info, sizeof(struct sn_irq_info));
 158
 159         /* Free the old PROM new_irq_info structure */
 160         sn_intr_free(local_nasid, local_widget, new_irq_info);
 161         unregister_intr_pda(new_irq_info);
 162
 163         /* allocate a new PROM new_irq_info struct */
 164         status = sn_intr_alloc(local_nasid, local_widget,
 165                                new_irq_info, vector,
 166                                nasid, slice);
 167
 168         /* SAL call failed */
 169         if (status) {
 170                 kfree(new_irq_info);
 171                 return NULL;
 172         }
 173
 174         register_intr_pda(new_irq_info);
 175         spin_lock(&sn_irq_info_lock);
 176         list_replace_rcu(&sn_irq_info->list, &new_irq_info->list);
 177         spin_unlock(&sn_irq_info_lock);
 178         kfree_rcu(sn_irq_info, rcu);
 179
 180
 181 finish_up:
 182         /* Update kernels new_irq_info with new target info */
 183         cpuid = nasid_slice_to_cpuid(new_irq_info->irq_nasid,
 184                                      new_irq_info->irq_slice);
 185         new_irq_info->irq_cpuid = cpuid;
 186
 187         pci_provider = sn_pci_provider[new_irq_info->irq_bridge_type];
 188
 189         /*
 190          * If this represents a line interrupt, target it.  If it's
 191          * an msi (irq_int_bit < 0), it's already targeted.
 192          */
 193         if (new_irq_info->irq_int_bit >= 0 &&
 194             pci_provider && pci_provider->target_interrupt)
 195                 (pci_provider->target_interrupt)(new_irq_info);
 196
 197 #ifdef CONFIG_SMP
 198         cpuphys = cpu_physical_id(cpuid);
 199         set_irq_affinity_info((vector & 0xff), cpuphys, 0);
 200 #endif
 201
 202         return new_irq_info;
 203 }
 204
 205 static int sn_set_affinity_irq(struct irq_data *data,
 206                                const struct cpumask *mask, bool force)
 207 {
 208         struct sn_irq_info *sn_irq_info, *sn_irq_info_safe;
 209         unsigned int irq = data->irq;
 210         nasid_t nasid;
 211         int slice;
 212
 213         nasid = cpuid_to_nasid(cpumask_first(mask));
 214         slice = cpuid_to_slice(cpumask_first(mask));
 215
 216         list_for_each_entry_safe(sn_irq_info, sn_irq_info_safe,
 217                                  sn_irq_lh[irq], list)
 218                 (void)sn_retarget_vector(sn_irq_info, nasid, slice);
 219
 220         return 0;
 221 }
 222
 223 #ifdef CONFIG_SMP
 224 void sn_set_err_irq_affinity(unsigned int irq)
 225 {
 226         /*
 227          * On systems which support CPU disabling (SHub2), all error interrupts
 228          * are targeted at the boot CPU.
 229          */
 230         if (is_shub2() && sn_prom_feature_available(PRF_CPU_DISABLE_SUPPORT))
 231                 set_irq_affinity_info(irq, cpu_physical_id(0), 0);
 232 }
 233 #else
 234 void sn_set_err_irq_affinity(unsigned int irq) { }
 235 #endif
 236
 237 static void
 238 sn_mask_irq(struct irq_data *data)
 239 {
 240 }
 241
 242 static void
 243 sn_unmask_irq(struct irq_data *data)
 244 {
 245 }
 246
 247 struct irq_chip irq_type_sn = {
 248         .name                   = "SN hub",
 249         .irq_startup            = sn_startup_irq,
 250         .irq_shutdown           = sn_shutdown_irq,
 251         .irq_enable             = sn_enable_irq,
 252         .irq_disable            = sn_disable_irq,
 253         .irq_ack                = sn_ack_irq,
 254         .irq_mask               = sn_mask_irq,
 255         .irq_unmask             = sn_unmask_irq,
 256         .irq_set_affinity       = sn_set_affinity_irq
 257 };
 258
 259 ia64_vector sn_irq_to_vector(int irq)
 260 {
 261         if (irq >= IA64_NUM_VECTORS)
 262                 return 0;
 263         return (ia64_vector)irq;
 264 }
 265
 266 unsigned int sn_local_vector_to_irq(u8 vector)
 267 {
 268         return (CPU_VECTOR_TO_IRQ(smp_processor_id(), vector));
 269 }
 270
 271 void sn_irq_init(void)
 272 {
 273         int i;
 274
 275         ia64_first_device_vector = IA64_SN2_FIRST_DEVICE_VECTOR;
 276         ia64_last_device_vector = IA64_SN2_LAST_DEVICE_VECTOR;
 277
 278         for (i = 0; i < NR_IRQS; i++) {
 279                 if (irq_get_chip(i) == &no_irq_chip)
 280                         irq_set_chip(i, &irq_type_sn);
 281         }
 282 }
 283
 284 static void register_intr_pda(struct sn_irq_info *sn_irq_info)
 285 {
 286         int irq = sn_irq_info->irq_irq;
 287         int cpu = sn_irq_info->irq_cpuid;
 288
 289         if (pdacpu(cpu)->sn_last_irq < irq) {
 290                 pdacpu(cpu)->sn_last_irq = irq;
 291         }
 292
 293         if (pdacpu(cpu)->sn_first_irq == 0 || pdacpu(cpu)->sn_first_irq > irq)
 294                 pdacpu(cpu)->sn_first_irq = irq;
 295 }
 296
 297 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info)
 298 {
 299         int irq = sn_irq_info->irq_irq;
 300         int cpu = sn_irq_info->irq_cpuid;
 301         struct sn_irq_info *tmp_irq_info;
 302         int i, foundmatch;
 303
 304         rcu_read_lock();
 305         if (pdacpu(cpu)->sn_last_irq == irq) {
 306                 foundmatch = 0;
 307                 for (i = pdacpu(cpu)->sn_last_irq - 1;
 308                      i && !foundmatch; i--) {
 309                         list_for_each_entry_rcu(tmp_irq_info,
 310                                                 sn_irq_lh[i],
 311                                                 list) {
 312                                 if (tmp_irq_info->irq_cpuid == cpu) {
 313                                         foundmatch = 1;
 314                                         break;
 315                                 }
 316                         }
 317                 }
 318                 pdacpu(cpu)->sn_last_irq = i;
 319         }
 320
 321         if (pdacpu(cpu)->sn_first_irq == irq) {
 322                 foundmatch = 0;
 323                 for (i = pdacpu(cpu)->sn_first_irq + 1;
 324                      i < NR_IRQS && !foundmatch; i++) {
 325                         list_for_each_entry_rcu(tmp_irq_info,
 326                                                 sn_irq_lh[i],
 327                                                 list) {
 328                                 if (tmp_irq_info->irq_cpuid == cpu) {
 329                                         foundmatch = 1;
 330                                         break;
 331                                 }
 332                         }
 333                 }
 334                 pdacpu(cpu)->sn_first_irq = ((i == NR_IRQS) ? 0 : i);
 335         }
 336         rcu_read_unlock();
 337 }
 338
 339 void sn_irq_fixup(struct pci_dev *pci_dev, struct sn_irq_info *sn_irq_info)
 340 {
 341         nasid_t nasid = sn_irq_info->irq_nasid;
 342         int slice = sn_irq_info->irq_slice;
 343         int cpu = nasid_slice_to_cpuid(nasid, slice);
 344 #ifdef CONFIG_SMP
 345         int cpuphys;
 346 #endif
 347
 348         pci_dev_get(pci_dev);
 349         sn_irq_info->irq_cpuid = cpu;
 350         sn_irq_info->irq_pciioinfo = SN_PCIDEV_INFO(pci_dev);
 351
 352         /* link it into the sn_irq[irq] list */
 353         spin_lock(&sn_irq_info_lock);
 354         list_add_rcu(&sn_irq_info->list, sn_irq_lh[sn_irq_info->irq_irq]);
 355         reserve_irq_vector(sn_irq_info->irq_irq);
 356         spin_unlock(&sn_irq_info_lock);
 357
 358         register_intr_pda(sn_irq_info);
 359 #ifdef CONFIG_SMP
 360         cpuphys = cpu_physical_id(cpu);
 361         set_irq_affinity_info(sn_irq_info->irq_irq, cpuphys, 0);
 362         /*
 363          * Affinity was set by the PROM, prevent it from
 364          * being reset by the request_irq() path.
 365          */
 366         irqd_mark_affinity_was_set(irq_get_irq_data(sn_irq_info->irq_irq));
 367 #endif
 368 }
 369
 370 void sn_irq_unfixup(struct pci_dev *pci_dev)
 371 {
 372         struct sn_irq_info *sn_irq_info;
 373
 374         /* Only cleanup IRQ stuff if this device has a host bus context */
 375         if (!SN_PCIDEV_BUSSOFT(pci_dev))
 376                 return;
 377
 378         sn_irq_info = SN_PCIDEV_INFO(pci_dev)->pdi_sn_irq_info;
 379         if (!sn_irq_info)
 380                 return;
 381         if (!sn_irq_info->irq_irq) {
 382                 kfree(sn_irq_info);
 383                 return;
 384         }
 385
 386         unregister_intr_pda(sn_irq_info);
 387         spin_lock(&sn_irq_info_lock);
 388         list_del_rcu(&sn_irq_info->list);
 389         spin_unlock(&sn_irq_info_lock);
 390         if (list_empty(sn_irq_lh[sn_irq_info->irq_irq]))
 391                 free_irq_vector(sn_irq_info->irq_irq);
 392         kfree_rcu(sn_irq_info, rcu);
 393         pci_dev_put(pci_dev);
 394
 395 }
 396
 397 static inline void
 398 sn_call_force_intr_provider(struct sn_irq_info *sn_irq_info)
 399 {
 400         struct sn_pcibus_provider *pci_provider;
 401
 402         pci_provider = sn_pci_provider[sn_irq_info->irq_bridge_type];
 403
 404         /* Don't force an interrupt if the irq has been disabled */
 405         if (!irqd_irq_disabled(irq_get_irq_data(sn_irq_info->irq_irq)) &&
 406             pci_provider && pci_provider->force_interrupt)
 407                 (*pci_provider->force_interrupt)(sn_irq_info);
 408 }
 409
 410 /*
 411  * Check for lost interrupts.  If the PIC int_status reg. says that
 412  * an interrupt has been sent, but not handled, and the interrupt
 413  * is not pending in either the cpu irr regs or in the soft irr regs,
 414  * and the interrupt is not in service, then the interrupt may have
 415  * been lost.  Force an interrupt on that pin.  It is possible that
 416  * the interrupt is in flight, so we may generate a spurious interrupt,
 417  * but we should never miss a real lost interrupt.
 418  */
 419 static void sn_check_intr(int irq, struct sn_irq_info *sn_irq_info)
 420 {
 421         u64 regval;
 422         struct pcidev_info *pcidev_info;
 423         struct pcibus_info *pcibus_info;
 424
 425         /*
 426          * Bridge types attached to TIO (anything but PIC) do not need this WAR
 427          * since they do not target Shub II interrupt registers.  If that
 428          * ever changes, this check needs to accommodate.
 429          */
 430         if (sn_irq_info->irq_bridge_type != PCIIO_ASIC_TYPE_PIC)
 431                 return;
 432
 433         pcidev_info = (struct pcidev_info *)sn_irq_info->irq_pciioinfo;
 434         if (!pcidev_info)
 435                 return;
 436
 437         pcibus_info =
 438             (struct pcibus_info *)pcidev_info->pdi_host_pcidev_info->
 439             pdi_pcibus_info;
 440         regval = pcireg_intr_status_get(pcibus_info);
 441
 442         if (!ia64_get_irr(irq_to_vector(irq))) {
 443                 if (!test_bit(irq, pda->sn_in_service_ivecs)) {
 444                         regval &= 0xff;
 445                         if (sn_irq_info->irq_int_bit & regval &
 446                             sn_irq_info->irq_last_intr) {
 447                                 regval &= ~(sn_irq_info->irq_int_bit & regval);
 448                                 sn_call_force_intr_provider(sn_irq_info);
 449                         }
 450                 }
 451         }
 452         sn_irq_info->irq_last_intr = regval;
 453 }
 454
 455 void sn_lb_int_war_check(void)
 456 {
 457         struct sn_irq_info *sn_irq_info;
 458         int i;
 459
 460         if (!sn_ioif_inited || pda->sn_first_irq == 0)
 461                 return;
 462
 463         rcu_read_lock();
 464         for (i = pda->sn_first_irq; i <= pda->sn_last_irq; i++) {
 465                 list_for_each_entry_rcu(sn_irq_info, sn_irq_lh[i], list) {
 466                         sn_check_intr(i, sn_irq_info);
 467                 }
 468         }
 469         rcu_read_unlock();
 470 }
 471
 472 void __init sn_irq_lh_init(void)
 473 {
 474         int i;
 475
 476         sn_irq_lh = kmalloc(sizeof(struct list_head *) * NR_IRQS, GFP_KERNEL);
 477         if (!sn_irq_lh)
 478                 panic("SN PCI INIT: Failed to allocate memory for PCI init\n");
 479
 480         for (i = 0; i < NR_IRQS; i++) {
 481                 sn_irq_lh[i] = kmalloc(sizeof(struct list_head), GFP_KERNEL);
 482                 if (!sn_irq_lh[i])
 483                         panic("SN PCI INIT: Failed IRQ memory allocation\n");
 484
 485                 INIT_LIST_HEAD(sn_irq_lh[i]);
 486         }
 487 }