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) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
   9  */
  10
  11 #include <linux/irq.h>
  12 #include <asm/sn/intr.h>
  13 #include <asm/sn/addrs.h>
  14 #include <asm/sn/arch.h>
  15 #include "xtalk/xwidgetdev.h"
  16 #include <asm/sn/pcibus_provider_defs.h>
  17 #include <asm/sn/pcidev.h>
  18 #include "pci/pcibr_provider.h"
  19 #include <asm/sn/shub_mmr.h>
  20 #include <asm/sn/sn_sal.h>
  21
  22 static void force_interrupt(int irq);
  23 static void register_intr_pda(struct sn_irq_info *sn_irq_info);
  24 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info);
  25
  26 extern int sn_force_interrupt_flag;
  27 extern int sn_ioif_inited;
  28 struct sn_irq_info **sn_irq;
  29
  30 static inline uint64_t sn_intr_alloc(nasid_t local_nasid, int local_widget,
  31                                      u64 sn_irq_info,
  32                                      int req_irq, nasid_t req_nasid,
  33                                      int req_slice)
  34 {
  35         struct ia64_sal_retval ret_stuff;
  36         ret_stuff.status = 0;
  37         ret_stuff.v0 = 0;
  38
  39         SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
  40                         (u64) SAL_INTR_ALLOC, (u64) local_nasid,
  41                         (u64) local_widget, (u64) sn_irq_info, (u64) req_irq,
  42                         (u64) req_nasid, (u64) req_slice);
  43         return ret_stuff.status;
  44 }
  45
  46 static inline void sn_intr_free(nasid_t local_nasid, int local_widget,
  47                                 struct sn_irq_info *sn_irq_info)
  48 {
  49         struct ia64_sal_retval ret_stuff;
  50         ret_stuff.status = 0;
  51         ret_stuff.v0 = 0;
  52
  53         SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
  54                         (u64) SAL_INTR_FREE, (u64) local_nasid,
  55                         (u64) local_widget, (u64) sn_irq_info->irq_irq,
  56                         (u64) sn_irq_info->irq_cookie, 0, 0);
  57 }
  58
  59 static unsigned int sn_startup_irq(unsigned int irq)
  60 {
  61         return 0;
  62 }
  63
  64 static void sn_shutdown_irq(unsigned int irq)
  65 {
  66 }
  67
  68 static void sn_disable_irq(unsigned int irq)
  69 {
  70 }
  71
  72 static void sn_enable_irq(unsigned int irq)
  73 {
  74 }
  75
  76 static void sn_ack_irq(unsigned int irq)
  77 {
  78         uint64_t event_occurred, mask = 0;
  79         int nasid;
  80
  81         irq = irq & 0xff;
  82         nasid = get_nasid();
  83         event_occurred =
  84             HUB_L((uint64_t *) GLOBAL_MMR_ADDR(nasid, SH_EVENT_OCCURRED));
  85         mask = event_occurred & SH_ALL_INT_MASK;
  86         HUB_S((uint64_t *) GLOBAL_MMR_ADDR(nasid, SH_EVENT_OCCURRED_ALIAS),
  87                  mask);
  88         __set_bit(irq, (volatile void *)pda->sn_in_service_ivecs);
  89
  90         move_irq(irq);
  91 }
  92
  93 static void sn_end_irq(unsigned int irq)
  94 {
  95         int nasid;
  96         int ivec;
  97         uint64_t event_occurred;
  98
  99         ivec = irq & 0xff;
 100         if (ivec == SGI_UART_VECTOR) {
 101                 nasid = get_nasid();
 102                 event_occurred = HUB_L((uint64_t *) GLOBAL_MMR_ADDR
 103                                        (nasid, SH_EVENT_OCCURRED));
 104                 /* If the UART bit is set here, we may have received an
 105                  * interrupt from the UART that the driver missed.  To
 106                  * make sure, we IPI ourselves to force us to look again.
 107                  */
 108                 if (event_occurred & SH_EVENT_OCCURRED_UART_INT_MASK) {
 109                         platform_send_ipi(smp_processor_id(), SGI_UART_VECTOR,
 110                                           IA64_IPI_DM_INT, 0);
 111                 }
 112         }
 113         __clear_bit(ivec, (volatile void *)pda->sn_in_service_ivecs);
 114         if (sn_force_interrupt_flag)
 115                 force_interrupt(irq);
 116 }
 117
 118 static void sn_set_affinity_irq(unsigned int irq, cpumask_t mask)
 119 {
 120         struct sn_irq_info *sn_irq_info = sn_irq[irq];
 121         struct sn_irq_info *tmp_sn_irq_info;
 122         int cpuid, cpuphys;
 123         nasid_t t_nasid;        /* nasid to target */
 124         int t_slice;            /* slice to target */
 125
 126         /* allocate a temp sn_irq_info struct to get new target info */
 127         tmp_sn_irq_info = kmalloc(sizeof(*tmp_sn_irq_info), GFP_KERNEL);
 128         if (!tmp_sn_irq_info)
 129                 return;
 130
 131         cpuid = first_cpu(mask);
 132         cpuphys = cpu_physical_id(cpuid);
 133         t_nasid = cpuid_to_nasid(cpuid);
 134         t_slice = cpuid_to_slice(cpuid);
 135
 136         while (sn_irq_info) {
 137                 int status;
 138                 int local_widget;
 139                 uint64_t bridge = (uint64_t) sn_irq_info->irq_bridge;
 140                 nasid_t local_nasid = NASID_GET(bridge);
 141
 142                 if (!bridge)
 143                         break;  /* irq is not a device interrupt */
 144
 145                 if (local_nasid & 1)
 146                         local_widget = TIO_SWIN_WIDGETNUM(bridge);
 147                 else
 148                         local_widget = SWIN_WIDGETNUM(bridge);
 149
 150                 /* Free the old PROM sn_irq_info structure */
 151                 sn_intr_free(local_nasid, local_widget, sn_irq_info);
 152
 153                 /* allocate a new PROM sn_irq_info struct */
 154                 status = sn_intr_alloc(local_nasid, local_widget,
 155                                        __pa(tmp_sn_irq_info), irq, t_nasid,
 156                                        t_slice);
 157
 158                 if (status == 0) {
 159                         /* Update kernels sn_irq_info with new target info */
 160                         unregister_intr_pda(sn_irq_info);
 161                         sn_irq_info->irq_cpuid = cpuid;
 162                         sn_irq_info->irq_nasid = t_nasid;
 163                         sn_irq_info->irq_slice = t_slice;
 164                         sn_irq_info->irq_xtalkaddr =
 165                             tmp_sn_irq_info->irq_xtalkaddr;
 166                         sn_irq_info->irq_cookie = tmp_sn_irq_info->irq_cookie;
 167                         register_intr_pda(sn_irq_info);
 168
 169                         if (IS_PCI_BRIDGE_ASIC(sn_irq_info->irq_bridge_type)) {
 170                                 pcibr_change_devices_irq(sn_irq_info);
 171                         }
 172
 173                         sn_irq_info = sn_irq_info->irq_next;
 174
 175 #ifdef CONFIG_SMP
 176                         set_irq_affinity_info((irq & 0xff), cpuphys, 0);
 177 #endif
 178                 } else {
 179                         break;  /* snp_affinity failed the intr_alloc */
 180                 }
 181         }
 182         kfree(tmp_sn_irq_info);
 183 }
 184
 185 struct hw_interrupt_type irq_type_sn = {
 186         "SN hub",
 187         sn_startup_irq,
 188         sn_shutdown_irq,
 189         sn_enable_irq,
 190         sn_disable_irq,
 191         sn_ack_irq,
 192         sn_end_irq,
 193         sn_set_affinity_irq
 194 };
 195
 196 unsigned int sn_local_vector_to_irq(u8 vector)
 197 {
 198         return (CPU_VECTOR_TO_IRQ(smp_processor_id(), vector));
 199 }
 200
 201 void sn_irq_init(void)
 202 {
 203         int i;
 204         irq_desc_t *base_desc = irq_desc;
 205
 206         for (i = 0; i < NR_IRQS; i++) {
 207                 if (base_desc[i].handler == &no_irq_type) {
 208                         base_desc[i].handler = &irq_type_sn;
 209                 }
 210         }
 211 }
 212
 213 static void register_intr_pda(struct sn_irq_info *sn_irq_info)
 214 {
 215         int irq = sn_irq_info->irq_irq;
 216         int cpu = sn_irq_info->irq_cpuid;
 217
 218         if (pdacpu(cpu)->sn_last_irq < irq) {
 219                 pdacpu(cpu)->sn_last_irq = irq;
 220         }
 221
 222         if (pdacpu(cpu)->sn_first_irq == 0 || pdacpu(cpu)->sn_first_irq > irq) {
 223                 pdacpu(cpu)->sn_first_irq = irq;
 224         }
 225 }
 226
 227 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info)
 228 {
 229         int irq = sn_irq_info->irq_irq;
 230         int cpu = sn_irq_info->irq_cpuid;
 231         struct sn_irq_info *tmp_irq_info;
 232         int i, foundmatch;
 233
 234         if (pdacpu(cpu)->sn_last_irq == irq) {
 235                 foundmatch = 0;
 236                 for (i = pdacpu(cpu)->sn_last_irq - 1; i; i--) {
 237                         tmp_irq_info = sn_irq[i];
 238                         while (tmp_irq_info) {
 239                                 if (tmp_irq_info->irq_cpuid == cpu) {
 240                                         foundmatch++;
 241                                         break;
 242                                 }
 243                                 tmp_irq_info = tmp_irq_info->irq_next;
 244                         }
 245                         if (foundmatch) {
 246                                 break;
 247                         }
 248                 }
 249                 pdacpu(cpu)->sn_last_irq = i;
 250         }
 251
 252         if (pdacpu(cpu)->sn_first_irq == irq) {
 253                 foundmatch = 0;
 254                 for (i = pdacpu(cpu)->sn_first_irq + 1; i < NR_IRQS; i++) {
 255                         tmp_irq_info = sn_irq[i];
 256                         while (tmp_irq_info) {
 257                                 if (tmp_irq_info->irq_cpuid == cpu) {
 258                                         foundmatch++;
 259                                         break;
 260                                 }
 261                                 tmp_irq_info = tmp_irq_info->irq_next;
 262                         }
 263                         if (foundmatch) {
 264                                 break;
 265                         }
 266                 }
 267                 pdacpu(cpu)->sn_first_irq = ((i == NR_IRQS) ? 0 : i);
 268         }
 269 }
 270
 271 struct sn_irq_info *sn_irq_alloc(nasid_t local_nasid, int local_widget, int irq,
 272                                  nasid_t nasid, int slice)
 273 {
 274         struct sn_irq_info *sn_irq_info;
 275         int status;
 276
 277         sn_irq_info = kmalloc(sizeof(*sn_irq_info), GFP_KERNEL);
 278         if (sn_irq_info == NULL)
 279                 return NULL;
 280
 281         memset(sn_irq_info, 0x0, sizeof(*sn_irq_info));
 282
 283         status =
 284             sn_intr_alloc(local_nasid, local_widget, __pa(sn_irq_info), irq,
 285                           nasid, slice);
 286
 287         if (status) {
 288                 kfree(sn_irq_info);
 289                 return NULL;
 290         } else {
 291                 return sn_irq_info;
 292         }
 293 }
 294
 295 void sn_irq_free(struct sn_irq_info *sn_irq_info)
 296 {
 297         uint64_t bridge = (uint64_t) sn_irq_info->irq_bridge;
 298         nasid_t local_nasid = NASID_GET(bridge);
 299         int local_widget;
 300
 301         if (local_nasid & 1)    /* tio check */
 302                 local_widget = TIO_SWIN_WIDGETNUM(bridge);
 303         else
 304                 local_widget = SWIN_WIDGETNUM(bridge);
 305
 306         sn_intr_free(local_nasid, local_widget, sn_irq_info);
 307
 308         kfree(sn_irq_info);
 309 }
 310
 311 void sn_irq_fixup(struct pci_dev *pci_dev, struct sn_irq_info *sn_irq_info)
 312 {
 313         nasid_t nasid = sn_irq_info->irq_nasid;
 314         int slice = sn_irq_info->irq_slice;
 315         int cpu = nasid_slice_to_cpuid(nasid, slice);
 316
 317         sn_irq_info->irq_cpuid = cpu;
 318         sn_irq_info->irq_pciioinfo = SN_PCIDEV_INFO(pci_dev);
 319
 320         /* link it into the sn_irq[irq] list */
 321         sn_irq_info->irq_next = sn_irq[sn_irq_info->irq_irq];
 322         sn_irq[sn_irq_info->irq_irq] = sn_irq_info;
 323
 324         (void)register_intr_pda(sn_irq_info);
 325 }
 326
 327 static void force_interrupt(int irq)
 328 {
 329         struct sn_irq_info *sn_irq_info;
 330
 331         if (!sn_ioif_inited)
 332                 return;
 333         sn_irq_info = sn_irq[irq];
 334         while (sn_irq_info) {
 335                 if (IS_PCI_BRIDGE_ASIC(sn_irq_info->irq_bridge_type) &&
 336                     (sn_irq_info->irq_bridge != NULL)) {
 337                         pcibr_force_interrupt(sn_irq_info);
 338                 }
 339                 sn_irq_info = sn_irq_info->irq_next;
 340         }
 341 }
 342
 343 /*
 344  * Check for lost interrupts.  If the PIC int_status reg. says that
 345  * an interrupt has been sent, but not handled, and the interrupt
 346  * is not pending in either the cpu irr regs or in the soft irr regs,
 347  * and the interrupt is not in service, then the interrupt may have
 348  * been lost.  Force an interrupt on that pin.  It is possible that
 349  * the interrupt is in flight, so we may generate a spurious interrupt,
 350  * but we should never miss a real lost interrupt.
 351  */
 352 static void sn_check_intr(int irq, struct sn_irq_info *sn_irq_info)
 353 {
 354         uint64_t regval;
 355         int irr_reg_num;
 356         int irr_bit;
 357         uint64_t irr_reg;
 358         struct pcidev_info *pcidev_info;
 359         struct pcibus_info *pcibus_info;
 360
 361         pcidev_info = (struct pcidev_info *)sn_irq_info->irq_pciioinfo;
 362         if (!pcidev_info)
 363                 return;
 364
 365         pcibus_info =
 366             (struct pcibus_info *)pcidev_info->pdi_host_pcidev_info->
 367             pdi_pcibus_info;
 368         regval = pcireg_intr_status_get(pcibus_info);
 369
 370         irr_reg_num = irq_to_vector(irq) / 64;
 371         irr_bit = irq_to_vector(irq) % 64;
 372         switch (irr_reg_num) {
 373         case 0:
 374                 irr_reg = ia64_getreg(_IA64_REG_CR_IRR0);
 375                 break;
 376         case 1:
 377                 irr_reg = ia64_getreg(_IA64_REG_CR_IRR1);
 378                 break;
 379         case 2:
 380                 irr_reg = ia64_getreg(_IA64_REG_CR_IRR2);
 381                 break;
 382         case 3:
 383                 irr_reg = ia64_getreg(_IA64_REG_CR_IRR3);
 384                 break;
 385         }
 386         if (!test_bit(irr_bit, &irr_reg)) {
 387                 if (!test_bit(irq, pda->sn_soft_irr)) {
 388                         if (!test_bit(irq, pda->sn_in_service_ivecs)) {
 389                                 regval &= 0xff;
 390                                 if (sn_irq_info->irq_int_bit & regval &
 391                                     sn_irq_info->irq_last_intr) {
 392                                         regval &=
 393                                             ~(sn_irq_info->
 394                                               irq_int_bit & regval);
 395                                         pcibr_force_interrupt(sn_irq_info);
 396                                 }
 397                         }
 398                 }
 399         }
 400         sn_irq_info->irq_last_intr = regval;
 401 }
 402
 403 void sn_lb_int_war_check(void)
 404 {
 405         int i;
 406
 407         if (!sn_ioif_inited || pda->sn_first_irq == 0)
 408                 return;
 409         for (i = pda->sn_first_irq; i <= pda->sn_last_irq; i++) {
 410                 struct sn_irq_info *sn_irq_info = sn_irq[i];
 411                 while (sn_irq_info) {
 412                         /* Only call for PCI bridges that are fully initialized. */
 413                         if (IS_PCI_BRIDGE_ASIC(sn_irq_info->irq_bridge_type) &&
 414                             (sn_irq_info->irq_bridge != NULL)) {
 415                                 sn_check_intr(i, sn_irq_info);
 416                         }
 417                         sn_irq_info = sn_irq_info->irq_next;
 418                 }
 419         }
 420 }