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   1 /*
   2  * I/O SAPIC support.
   3  *
   4  * Copyright (C) 1999 Intel Corp.
   5  * Copyright (C) 1999 Asit Mallick <asit.k.mallick@intel.com>
   6  * Copyright (C) 2000-2002 J.I. Lee <jung-ik.lee@intel.com>
   7  * Copyright (C) 1999-2000, 2002-2003 Hewlett-Packard Co.
   8  *      David Mosberger-Tang <davidm@hpl.hp.com>
   9  * Copyright (C) 1999 VA Linux Systems
  10  * Copyright (C) 1999,2000 Walt Drummond <drummond@valinux.com>
  11  *
  12  * 00/04/19     D. Mosberger    Rewritten to mirror more closely the x86 I/O
  13  *                              APIC code.  In particular, we now have separate
  14  *                              handlers for edge and level triggered
  15  *                              interrupts.
  16  * 00/10/27     Asit Mallick, Goutham Rao <goutham.rao@intel.com> IRQ vector
  17  *                              allocation PCI to vector mapping, shared PCI
  18  *                              interrupts.
  19  * 00/10/27     D. Mosberger    Document things a bit more to make them more
  20  *                              understandable.  Clean up much of the old
  21  *                              IOSAPIC cruft.
  22  * 01/07/27     J.I. Lee        PCI irq routing, Platform/Legacy interrupts
  23  *                              and fixes for ACPI S5(SoftOff) support.
  24  * 02/01/23     J.I. Lee        iosapic pgm fixes for PCI irq routing from _PRT
  25  * 02/01/07     E. Focht        <efocht@ess.nec.de> Redirectable interrupt
  26  *                              vectors in iosapic_set_affinity(),
  27  *                              initializations for /proc/irq/#/smp_affinity
  28  * 02/04/02     P. Diefenbaugh  Cleaned up ACPI PCI IRQ routing.
  29  * 02/04/18     J.I. Lee        bug fix in iosapic_init_pci_irq
  30  * 02/04/30     J.I. Lee        bug fix in find_iosapic to fix ACPI PCI IRQ to
  31  *                              IOSAPIC mapping error
  32  * 02/07/29     T. Kochi        Allocate interrupt vectors dynamically
  33  * 02/08/04     T. Kochi        Cleaned up terminology (irq, global system
  34  *                              interrupt, vector, etc.)
  35  * 02/09/20     D. Mosberger    Simplified by taking advantage of ACPI's
  36  *                              pci_irq code.
  37  * 03/02/19     B. Helgaas      Make pcat_compat system-wide, not per-IOSAPIC.
  38  *                              Remove iosapic_address & gsi_base from
  39  *                              external interfaces.  Rationalize
  40  *                              __init/__devinit attributes.
  41  * 04/12/04 Ashok Raj   <ashok.raj@intel.com> Intel Corporation 2004
  42  *                              Updated to work with irq migration necessary
  43  *                              for CPU Hotplug
  44  */
  45 /*
  46  * Here is what the interrupt logic between a PCI device and the kernel looks
  47  * like:
  48  *
  49  * (1) A PCI device raises one of the four interrupt pins (INTA, INTB, INTC,
  50  *     INTD).  The device is uniquely identified by its bus-, and slot-number
  51  *     (the function number does not matter here because all functions share
  52  *     the same interrupt lines).
  53  *
  54  * (2) The motherboard routes the interrupt line to a pin on a IOSAPIC
  55  *     controller.  Multiple interrupt lines may have to share the same
  56  *     IOSAPIC pin (if they're level triggered and use the same polarity).
  57  *     Each interrupt line has a unique Global System Interrupt (GSI) number
  58  *     which can be calculated as the sum of the controller's base GSI number
  59  *     and the IOSAPIC pin number to which the line connects.
  60  *
  61  * (3) The IOSAPIC uses an internal routing table entries (RTEs) to map the
  62  * IOSAPIC pin into the IA-64 interrupt vector.  This interrupt vector is then
  63  * sent to the CPU.
  64  *
  65  * (4) The kernel recognizes an interrupt as an IRQ.  The IRQ interface is
  66  *     used as architecture-independent interrupt handling mechanism in Linux.
  67  *     As an IRQ is a number, we have to have
  68  *     IA-64 interrupt vector number <-> IRQ number mapping.  On smaller
  69  *     systems, we use one-to-one mapping between IA-64 vector and IRQ.  A
  70  *     platform can implement platform_irq_to_vector(irq) and
  71  *     platform_local_vector_to_irq(vector) APIs to differentiate the mapping.
  72  *     Please see also include/asm-ia64/hw_irq.h for those APIs.
  73  *
  74  * To sum up, there are three levels of mappings involved:
  75  *
  76  *      PCI pin -> global system interrupt (GSI) -> IA-64 vector <-> IRQ
  77  *
  78  * Note: The term "IRQ" is loosely used everywhere in Linux kernel to
  79  * describeinterrupts.  Now we use "IRQ" only for Linux IRQ's.  ISA IRQ
  80  * (isa_irq) is the only exception in this source code.
  81  */
  82 #include <linux/config.h>
  83
  84 #include <linux/acpi.h>
  85 #include <linux/init.h>
  86 #include <linux/irq.h>
  87 #include <linux/kernel.h>
  88 #include <linux/list.h>
  89 #include <linux/pci.h>
  90 #include <linux/smp.h>
  91 #include <linux/smp_lock.h>
  92 #include <linux/string.h>
  93 #include <linux/bootmem.h>
  94
  95 #include <asm/delay.h>
  96 #include <asm/hw_irq.h>
  97 #include <asm/io.h>
  98 #include <asm/iosapic.h>
  99 #include <asm/machvec.h>
 100 #include <asm/processor.h>
 101 #include <asm/ptrace.h>
 102 #include <asm/system.h>
 103
 104 #undef DEBUG_INTERRUPT_ROUTING
 105
 106 #ifdef DEBUG_INTERRUPT_ROUTING
 107 #define DBG(fmt...)     printk(fmt)
 108 #else
 109 #define DBG(fmt...)
 110 #endif
 111
 112 #define NR_PREALLOCATE_RTE_ENTRIES \
 113         (PAGE_SIZE / sizeof(struct iosapic_rte_info))
 114 #define RTE_PREALLOCATED        (1)
 115
 116 static DEFINE_SPINLOCK(iosapic_lock);
 117
 118 /*
 119  * These tables map IA-64 vectors to the IOSAPIC pin that generates this
 120  * vector.
 121  */
 122
 123 struct iosapic_rte_info {
 124         struct list_head rte_list;      /* node in list of RTEs sharing the
 125                                          * same vector */
 126         char __iomem    *addr;          /* base address of IOSAPIC */
 127         unsigned int    gsi_base;       /* first GSI assigned to this
 128                                          * IOSAPIC */
 129         char            rte_index;      /* IOSAPIC RTE index */
 130         int             refcnt;         /* reference counter */
 131         unsigned int    flags;          /* flags */
 132 } ____cacheline_aligned;
 133
 134 static struct iosapic_intr_info {
 135         struct list_head rtes;          /* RTEs using this vector (empty =>
 136                                          * not an IOSAPIC interrupt) */
 137         int             count;          /* # of RTEs that shares this vector */
 138         u32             low32;          /* current value of low word of
 139                                          * Redirection table entry */
 140         unsigned int    dest;           /* destination CPU physical ID */
 141         unsigned char   dmode   : 3;    /* delivery mode (see iosapic.h) */
 142         unsigned char   polarity: 1;    /* interrupt polarity
 143                                          * (see iosapic.h) */
 144         unsigned char   trigger : 1;    /* trigger mode (see iosapic.h) */
 145 } iosapic_intr_info[IA64_NUM_VECTORS];
 146
 147 static struct iosapic {
 148         char __iomem    *addr;          /* base address of IOSAPIC */
 149         unsigned int    gsi_base;       /* first GSI assigned to this
 150                                          * IOSAPIC */
 151         unsigned short  num_rte;        /* # of RTEs on this IOSAPIC */
 152         int             rtes_inuse;     /* # of RTEs in use on this IOSAPIC */
 153 #ifdef CONFIG_NUMA
 154         unsigned short  node;           /* numa node association via pxm */
 155 #endif
 156 } iosapic_lists[NR_IOSAPICS];
 157
 158 static unsigned char pcat_compat __devinitdata; /* 8259 compatibility flag */
 159
 160 static int iosapic_kmalloc_ok;
 161 static LIST_HEAD(free_rte_list);
 162
 163 /*
 164  * Find an IOSAPIC associated with a GSI
 165  */
 166 static inline int
 167 find_iosapic (unsigned int gsi)
 168 {
 169         int i;
 170
 171         for (i = 0; i < NR_IOSAPICS; i++) {
 172                 if ((unsigned) (gsi - iosapic_lists[i].gsi_base) <
 173                     iosapic_lists[i].num_rte)
 174                         return i;
 175         }
 176
 177         return -1;
 178 }
 179
 180 static inline int
 181 _gsi_to_vector (unsigned int gsi)
 182 {
 183         struct iosapic_intr_info *info;
 184         struct iosapic_rte_info *rte;
 185
 186         for (info = iosapic_intr_info; info <
 187                      iosapic_intr_info + IA64_NUM_VECTORS; ++info)
 188                 list_for_each_entry(rte, &info->rtes, rte_list)
 189                         if (rte->gsi_base + rte->rte_index == gsi)
 190                                 return info - iosapic_intr_info;
 191         return -1;
 192 }
 193
 194 /*
 195  * Translate GSI number to the corresponding IA-64 interrupt vector.  If no
 196  * entry exists, return -1.
 197  */
 198 inline int
 199 gsi_to_vector (unsigned int gsi)
 200 {
 201         return _gsi_to_vector(gsi);
 202 }
 203
 204 int
 205 gsi_to_irq (unsigned int gsi)
 206 {
 207         unsigned long flags;
 208         int irq;
 209         /*
 210          * XXX fix me: this assumes an identity mapping between IA-64 vector
 211          * and Linux irq numbers...
 212          */
 213         spin_lock_irqsave(&iosapic_lock, flags);
 214         {
 215                 irq = _gsi_to_vector(gsi);
 216         }
 217         spin_unlock_irqrestore(&iosapic_lock, flags);
 218
 219         return irq;
 220 }
 221
 222 static struct iosapic_rte_info *gsi_vector_to_rte(unsigned int gsi,
 223                                                   unsigned int vec)
 224 {
 225         struct iosapic_rte_info *rte;
 226
 227         list_for_each_entry(rte, &iosapic_intr_info[vec].rtes, rte_list)
 228                 if (rte->gsi_base + rte->rte_index == gsi)
 229                         return rte;
 230         return NULL;
 231 }
 232
 233 static void
 234 set_rte (unsigned int gsi, unsigned int vector, unsigned int dest, int mask)
 235 {
 236         unsigned long pol, trigger, dmode;
 237         u32 low32, high32;
 238         char __iomem *addr;
 239         int rte_index;
 240         char redir;
 241         struct iosapic_rte_info *rte;
 242
 243         DBG(KERN_DEBUG"IOSAPIC: routing vector %d to 0x%x\n", vector, dest);
 244
 245         rte = gsi_vector_to_rte(gsi, vector);
 246         if (!rte)
 247                 return;         /* not an IOSAPIC interrupt */
 248
 249         rte_index = rte->rte_index;
 250         addr    = rte->addr;
 251         pol     = iosapic_intr_info[vector].polarity;
 252         trigger = iosapic_intr_info[vector].trigger;
 253         dmode   = iosapic_intr_info[vector].dmode;
 254
 255         redir = (dmode == IOSAPIC_LOWEST_PRIORITY) ? 1 : 0;
 256
 257 #ifdef CONFIG_SMP
 258         {
 259                 unsigned int irq;
 260
 261                 for (irq = 0; irq < NR_IRQS; ++irq)
 262                         if (irq_to_vector(irq) == vector) {
 263                                 set_irq_affinity_info(irq,
 264                                                       (int)(dest & 0xffff),
 265                                                       redir);
 266                                 break;
 267                         }
 268         }
 269 #endif
 270
 271         low32 = ((pol << IOSAPIC_POLARITY_SHIFT) |
 272                  (trigger << IOSAPIC_TRIGGER_SHIFT) |
 273                  (dmode << IOSAPIC_DELIVERY_SHIFT) |
 274                  ((mask ? 1 : 0) << IOSAPIC_MASK_SHIFT) |
 275                  vector);
 276
 277         /* dest contains both id and eid */
 278         high32 = (dest << IOSAPIC_DEST_SHIFT);
 279
 280         iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index), high32);
 281         iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
 282         iosapic_intr_info[vector].low32 = low32;
 283         iosapic_intr_info[vector].dest = dest;
 284 }
 285
 286 static void
 287 nop (unsigned int irq)
 288 {
 289         /* do nothing... */
 290 }
 291
 292 static void
 293 mask_irq (unsigned int irq)
 294 {
 295         unsigned long flags;
 296         char __iomem *addr;
 297         u32 low32;
 298         int rte_index;
 299         ia64_vector vec = irq_to_vector(irq);
 300         struct iosapic_rte_info *rte;
 301
 302         if (list_empty(&iosapic_intr_info[vec].rtes))
 303                 return;                 /* not an IOSAPIC interrupt! */
 304
 305         spin_lock_irqsave(&iosapic_lock, flags);
 306         {
 307                 /* set only the mask bit */
 308                 low32 = iosapic_intr_info[vec].low32 |= IOSAPIC_MASK;
 309                 list_for_each_entry(rte, &iosapic_intr_info[vec].rtes,
 310                                     rte_list) {
 311                         addr = rte->addr;
 312                         rte_index = rte->rte_index;
 313                         iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
 314                 }
 315         }
 316         spin_unlock_irqrestore(&iosapic_lock, flags);
 317 }
 318
 319 static void
 320 unmask_irq (unsigned int irq)
 321 {
 322         unsigned long flags;
 323         char __iomem *addr;
 324         u32 low32;
 325         int rte_index;
 326         ia64_vector vec = irq_to_vector(irq);
 327         struct iosapic_rte_info *rte;
 328
 329         if (list_empty(&iosapic_intr_info[vec].rtes))
 330                 return;                 /* not an IOSAPIC interrupt! */
 331
 332         spin_lock_irqsave(&iosapic_lock, flags);
 333         {
 334                 low32 = iosapic_intr_info[vec].low32 &= ~IOSAPIC_MASK;
 335                 list_for_each_entry(rte, &iosapic_intr_info[vec].rtes,
 336                                     rte_list) {
 337                         addr = rte->addr;
 338                         rte_index = rte->rte_index;
 339                         iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
 340                 }
 341         }
 342         spin_unlock_irqrestore(&iosapic_lock, flags);
 343 }
 344
 345
 346 static void
 347 iosapic_set_affinity (unsigned int irq, cpumask_t mask)
 348 {
 349 #ifdef CONFIG_SMP
 350         unsigned long flags;
 351         u32 high32, low32;
 352         int dest, rte_index;
 353         char __iomem *addr;
 354         int redir = (irq & IA64_IRQ_REDIRECTED) ? 1 : 0;
 355         ia64_vector vec;
 356         struct iosapic_rte_info *rte;
 357
 358         irq &= (~IA64_IRQ_REDIRECTED);
 359         vec = irq_to_vector(irq);
 360
 361         if (cpus_empty(mask))
 362                 return;
 363
 364         dest = cpu_physical_id(first_cpu(mask));
 365
 366         if (list_empty(&iosapic_intr_info[vec].rtes))
 367                 return;                 /* not an IOSAPIC interrupt */
 368
 369         set_irq_affinity_info(irq, dest, redir);
 370
 371         /* dest contains both id and eid */
 372         high32 = dest << IOSAPIC_DEST_SHIFT;
 373
 374         spin_lock_irqsave(&iosapic_lock, flags);
 375         {
 376                 low32 = iosapic_intr_info[vec].low32 &
 377                         ~(7 << IOSAPIC_DELIVERY_SHIFT);
 378
 379                 if (redir)
 380                         /* change delivery mode to lowest priority */
 381                         low32 |= (IOSAPIC_LOWEST_PRIORITY <<
 382                                   IOSAPIC_DELIVERY_SHIFT);
 383                 else
 384                         /* change delivery mode to fixed */
 385                         low32 |= (IOSAPIC_FIXED << IOSAPIC_DELIVERY_SHIFT);
 386
 387                 iosapic_intr_info[vec].low32 = low32;
 388                 iosapic_intr_info[vec].dest = dest;
 389                 list_for_each_entry(rte, &iosapic_intr_info[vec].rtes,
 390                                     rte_list) {
 391                         addr = rte->addr;
 392                         rte_index = rte->rte_index;
 393                         iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index),
 394                                       high32);
 395                         iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
 396                 }
 397         }
 398         spin_unlock_irqrestore(&iosapic_lock, flags);
 399 #endif
 400 }
 401
 402 /*
 403  * Handlers for level-triggered interrupts.
 404  */
 405
 406 static unsigned int
 407 iosapic_startup_level_irq (unsigned int irq)
 408 {
 409         unmask_irq(irq);
 410         return 0;
 411 }
 412
 413 static void
 414 iosapic_end_level_irq (unsigned int irq)
 415 {
 416         ia64_vector vec = irq_to_vector(irq);
 417         struct iosapic_rte_info *rte;
 418
 419         move_native_irq(irq);
 420         list_for_each_entry(rte, &iosapic_intr_info[vec].rtes, rte_list)
 421                 iosapic_eoi(rte->addr, vec);
 422 }
 423
 424 #define iosapic_shutdown_level_irq      mask_irq
 425 #define iosapic_enable_level_irq        unmask_irq
 426 #define iosapic_disable_level_irq       mask_irq
 427 #define iosapic_ack_level_irq           nop
 428
 429 struct hw_interrupt_type irq_type_iosapic_level = {
 430         .typename =     "IO-SAPIC-level",
 431         .startup =      iosapic_startup_level_irq,
 432         .shutdown =     iosapic_shutdown_level_irq,
 433         .enable =       iosapic_enable_level_irq,
 434         .disable =      iosapic_disable_level_irq,
 435         .ack =          iosapic_ack_level_irq,
 436         .end =          iosapic_end_level_irq,
 437         .set_affinity = iosapic_set_affinity
 438 };
 439
 440 /*
 441  * Handlers for edge-triggered interrupts.
 442  */
 443
 444 static unsigned int
 445 iosapic_startup_edge_irq (unsigned int irq)
 446 {
 447         unmask_irq(irq);
 448         /*
 449          * IOSAPIC simply drops interrupts pended while the
 450          * corresponding pin was masked, so we can't know if an
 451          * interrupt is pending already.  Let's hope not...
 452          */
 453         return 0;
 454 }
 455
 456 static void
 457 iosapic_ack_edge_irq (unsigned int irq)
 458 {
 459         irq_desc_t *idesc = irq_descp(irq);
 460
 461         move_native_irq(irq);
 462         /*
 463          * Once we have recorded IRQ_PENDING already, we can mask the
 464          * interrupt for real. This prevents IRQ storms from unhandled
 465          * devices.
 466          */
 467         if ((idesc->status & (IRQ_PENDING|IRQ_DISABLED)) ==
 468             (IRQ_PENDING|IRQ_DISABLED))
 469                 mask_irq(irq);
 470 }
 471
 472 #define iosapic_enable_edge_irq         unmask_irq
 473 #define iosapic_disable_edge_irq        nop
 474 #define iosapic_end_edge_irq            nop
 475
 476 struct hw_interrupt_type irq_type_iosapic_edge = {
 477         .typename =     "IO-SAPIC-edge",
 478         .startup =      iosapic_startup_edge_irq,
 479         .shutdown =     iosapic_disable_edge_irq,
 480         .enable =       iosapic_enable_edge_irq,
 481         .disable =      iosapic_disable_edge_irq,
 482         .ack =          iosapic_ack_edge_irq,
 483         .end =          iosapic_end_edge_irq,
 484         .set_affinity = iosapic_set_affinity
 485 };
 486
 487 unsigned int
 488 iosapic_version (char __iomem *addr)
 489 {
 490         /*
 491          * IOSAPIC Version Register return 32 bit structure like:
 492          * {
 493          *      unsigned int version   : 8;
 494          *      unsigned int reserved1 : 8;
 495          *      unsigned int max_redir : 8;
 496          *      unsigned int reserved2 : 8;
 497          * }
 498          */
 499         return iosapic_read(addr, IOSAPIC_VERSION);
 500 }
 501
 502 static int iosapic_find_sharable_vector (unsigned long trigger,
 503                                          unsigned long pol)
 504 {
 505         int i, vector = -1, min_count = -1;
 506         struct iosapic_intr_info *info;
 507
 508         /*
 509          * shared vectors for edge-triggered interrupts are not
 510          * supported yet
 511          */
 512         if (trigger == IOSAPIC_EDGE)
 513                 return -1;
 514
 515         for (i = IA64_FIRST_DEVICE_VECTOR; i <= IA64_LAST_DEVICE_VECTOR; i++) {
 516                 info = &iosapic_intr_info[i];
 517                 if (info->trigger == trigger && info->polarity == pol &&
 518                     (info->dmode == IOSAPIC_FIXED || info->dmode ==
 519                      IOSAPIC_LOWEST_PRIORITY)) {
 520                         if (min_count == -1 || info->count < min_count) {
 521                                 vector = i;
 522                                 min_count = info->count;
 523                         }
 524                 }
 525         }
 526
 527         return vector;
 528 }
 529
 530 /*
 531  * if the given vector is already owned by other,
 532  *  assign a new vector for the other and make the vector available
 533  */
 534 static void __init
 535 iosapic_reassign_vector (int vector)
 536 {
 537         int new_vector;
 538
 539         if (!list_empty(&iosapic_intr_info[vector].rtes)) {
 540                 new_vector = assign_irq_vector(AUTO_ASSIGN);
 541                 if (new_vector < 0)
 542                         panic("%s: out of interrupt vectors!\n", __FUNCTION__);
 543                 printk(KERN_INFO "Reassigning vector %d to %d\n",
 544                        vector, new_vector);
 545                 memcpy(&iosapic_intr_info[new_vector], &iosapic_intr_info[vector],
 546                        sizeof(struct iosapic_intr_info));
 547                 INIT_LIST_HEAD(&iosapic_intr_info[new_vector].rtes);
 548                 list_move(iosapic_intr_info[vector].rtes.next,
 549                           &iosapic_intr_info[new_vector].rtes);
 550                 memset(&iosapic_intr_info[vector], 0,
 551                        sizeof(struct iosapic_intr_info));
 552                 iosapic_intr_info[vector].low32 = IOSAPIC_MASK;
 553                 INIT_LIST_HEAD(&iosapic_intr_info[vector].rtes);
 554         }
 555 }
 556
 557 static struct iosapic_rte_info *iosapic_alloc_rte (void)
 558 {
 559         int i;
 560         struct iosapic_rte_info *rte;
 561         int preallocated = 0;
 562
 563         if (!iosapic_kmalloc_ok && list_empty(&free_rte_list)) {
 564                 rte = alloc_bootmem(sizeof(struct iosapic_rte_info) *
 565                                     NR_PREALLOCATE_RTE_ENTRIES);
 566                 if (!rte)
 567                         return NULL;
 568                 for (i = 0; i < NR_PREALLOCATE_RTE_ENTRIES; i++, rte++)
 569                         list_add(&rte->rte_list, &free_rte_list);
 570         }
 571
 572         if (!list_empty(&free_rte_list)) {
 573                 rte = list_entry(free_rte_list.next, struct iosapic_rte_info,
 574                                  rte_list);
 575                 list_del(&rte->rte_list);
 576                 preallocated++;
 577         } else {
 578                 rte = kmalloc(sizeof(struct iosapic_rte_info), GFP_ATOMIC);
 579                 if (!rte)
 580                         return NULL;
 581         }
 582
 583         memset(rte, 0, sizeof(struct iosapic_rte_info));
 584         if (preallocated)
 585                 rte->flags |= RTE_PREALLOCATED;
 586
 587         return rte;
 588 }
 589
 590 static void iosapic_free_rte (struct iosapic_rte_info *rte)
 591 {
 592         if (rte->flags & RTE_PREALLOCATED)
 593                 list_add_tail(&rte->rte_list, &free_rte_list);
 594         else
 595                 kfree(rte);
 596 }
 597
 598 static inline int vector_is_shared (int vector)
 599 {
 600         return (iosapic_intr_info[vector].count > 1);
 601 }
 602
 603 static int
 604 register_intr (unsigned int gsi, int vector, unsigned char delivery,
 605                unsigned long polarity, unsigned long trigger)
 606 {
 607         irq_desc_t *idesc;
 608         struct hw_interrupt_type *irq_type;
 609         int rte_index;
 610         int index;
 611         unsigned long gsi_base;
 612         void __iomem *iosapic_address;
 613         struct iosapic_rte_info *rte;
 614
 615         index = find_iosapic(gsi);
 616         if (index < 0) {
 617                 printk(KERN_WARNING "%s: No IOSAPIC for GSI %u\n",
 618                        __FUNCTION__, gsi);
 619                 return -ENODEV;
 620         }
 621
 622         iosapic_address = iosapic_lists[index].addr;
 623         gsi_base = iosapic_lists[index].gsi_base;
 624
 625         rte = gsi_vector_to_rte(gsi, vector);
 626         if (!rte) {
 627                 rte = iosapic_alloc_rte();
 628                 if (!rte) {
 629                         printk(KERN_WARNING "%s: cannot allocate memory\n",
 630                                __FUNCTION__);
 631                         return -ENOMEM;
 632                 }
 633
 634                 rte_index = gsi - gsi_base;
 635                 rte->rte_index  = rte_index;
 636                 rte->addr       = iosapic_address;
 637                 rte->gsi_base   = gsi_base;
 638                 rte->refcnt++;
 639                 list_add_tail(&rte->rte_list, &iosapic_intr_info[vector].rtes);
 640                 iosapic_intr_info[vector].count++;
 641                 iosapic_lists[index].rtes_inuse++;
 642         }
 643         else if (vector_is_shared(vector)) {
 644                 struct iosapic_intr_info *info = &iosapic_intr_info[vector];
 645                 if (info->trigger != trigger || info->polarity != polarity) {
 646                         printk (KERN_WARNING
 647                                 "%s: cannot override the interrupt\n",
 648                                 __FUNCTION__);
 649                         return -EINVAL;
 650                 }
 651         }
 652
 653         iosapic_intr_info[vector].polarity = polarity;
 654         iosapic_intr_info[vector].dmode    = delivery;
 655         iosapic_intr_info[vector].trigger  = trigger;
 656
 657         if (trigger == IOSAPIC_EDGE)
 658                 irq_type = &irq_type_iosapic_edge;
 659         else
 660                 irq_type = &irq_type_iosapic_level;
 661
 662         idesc = irq_descp(vector);
 663         if (idesc->handler != irq_type) {
 664                 if (idesc->handler != &no_irq_type)
 665                         printk(KERN_WARNING
 666                                "%s: changing vector %d from %s to %s\n",
 667                                __FUNCTION__, vector,
 668                                idesc->handler->typename, irq_type->typename);
 669                 idesc->handler = irq_type;
 670         }
 671         return 0;
 672 }
 673
 674 static unsigned int
 675 get_target_cpu (unsigned int gsi, int vector)
 676 {
 677 #ifdef CONFIG_SMP
 678         static int cpu = -1;
 679         extern int cpe_vector;
 680
 681         /*
 682          * In case of vector shared by multiple RTEs, all RTEs that
 683          * share the vector need to use the same destination CPU.
 684          */
 685         if (!list_empty(&iosapic_intr_info[vector].rtes))
 686                 return iosapic_intr_info[vector].dest;
 687
 688         /*
 689          * If the platform supports redirection via XTP, let it
 690          * distribute interrupts.
 691          */
 692         if (smp_int_redirect & SMP_IRQ_REDIRECTION)
 693                 return cpu_physical_id(smp_processor_id());
 694
 695         /*
 696          * Some interrupts (ACPI SCI, for instance) are registered
 697          * before the BSP is marked as online.
 698          */
 699         if (!cpu_online(smp_processor_id()))
 700                 return cpu_physical_id(smp_processor_id());
 701
 702 #ifdef CONFIG_ACPI
 703         if (cpe_vector > 0 && vector == IA64_CPEP_VECTOR)
 704                 return get_cpei_target_cpu();
 705 #endif
 706
 707 #ifdef CONFIG_NUMA
 708         {
 709                 int num_cpus, cpu_index, iosapic_index, numa_cpu, i = 0;
 710                 cpumask_t cpu_mask;
 711
 712                 iosapic_index = find_iosapic(gsi);
 713                 if (iosapic_index < 0 ||
 714                     iosapic_lists[iosapic_index].node == MAX_NUMNODES)
 715                         goto skip_numa_setup;
 716
 717                 cpu_mask = node_to_cpumask(iosapic_lists[iosapic_index].node);
 718
 719                 for_each_cpu_mask(numa_cpu, cpu_mask) {
 720                         if (!cpu_online(numa_cpu))
 721                                 cpu_clear(numa_cpu, cpu_mask);
 722                 }
 723
 724                 num_cpus = cpus_weight(cpu_mask);
 725
 726                 if (!num_cpus)
 727                         goto skip_numa_setup;
 728
 729                 /* Use vector assignment to distribute across cpus in node */
 730                 cpu_index = vector % num_cpus;
 731
 732                 for (numa_cpu = first_cpu(cpu_mask) ; i < cpu_index ; i++)
 733                         numa_cpu = next_cpu(numa_cpu, cpu_mask);
 734
 735                 if (numa_cpu != NR_CPUS)
 736                         return cpu_physical_id(numa_cpu);
 737         }
 738 skip_numa_setup:
 739 #endif
 740         /*
 741          * Otherwise, round-robin interrupt vectors across all the
 742          * processors.  (It'd be nice if we could be smarter in the
 743          * case of NUMA.)
 744          */
 745         do {
 746                 if (++cpu >= NR_CPUS)
 747                         cpu = 0;
 748         } while (!cpu_online(cpu));
 749
 750         return cpu_physical_id(cpu);
 751 #else  /* CONFIG_SMP */
 752         return cpu_physical_id(smp_processor_id());
 753 #endif
 754 }
 755
 756 /*
 757  * ACPI can describe IOSAPIC interrupts via static tables and namespace
 758  * methods.  This provides an interface to register those interrupts and
 759  * program the IOSAPIC RTE.
 760  */
 761 int
 762 iosapic_register_intr (unsigned int gsi,
 763                        unsigned long polarity, unsigned long trigger)
 764 {
 765         int vector, mask = 1, err;
 766         unsigned int dest;
 767         unsigned long flags;
 768         struct iosapic_rte_info *rte;
 769         u32 low32;
 770 again:
 771         /*
 772          * If this GSI has already been registered (i.e., it's a
 773          * shared interrupt, or we lost a race to register it),
 774          * don't touch the RTE.
 775          */
 776         spin_lock_irqsave(&iosapic_lock, flags);
 777         {
 778                 vector = gsi_to_vector(gsi);
 779                 if (vector > 0) {
 780                         rte = gsi_vector_to_rte(gsi, vector);
 781                         rte->refcnt++;
 782                         spin_unlock_irqrestore(&iosapic_lock, flags);
 783                         return vector;
 784                 }
 785         }
 786         spin_unlock_irqrestore(&iosapic_lock, flags);
 787
 788         /* If vector is running out, we try to find a sharable vector */
 789         vector = assign_irq_vector(AUTO_ASSIGN);
 790         if (vector < 0) {
 791                 vector = iosapic_find_sharable_vector(trigger, polarity);
 792                 if (vector < 0)
 793                         return -ENOSPC;
 794         }
 795
 796         spin_lock_irqsave(&irq_descp(vector)->lock, flags);
 797         spin_lock(&iosapic_lock);
 798         {
 799                 if (gsi_to_vector(gsi) > 0) {
 800                         if (list_empty(&iosapic_intr_info[vector].rtes))
 801                                 free_irq_vector(vector);
 802                         spin_unlock(&iosapic_lock);
 803                         spin_unlock_irqrestore(&irq_descp(vector)->lock,
 804                                                flags);
 805                         goto again;
 806                 }
 807
 808                 dest = get_target_cpu(gsi, vector);
 809                 err = register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY,
 810                               polarity, trigger);
 811                 if (err < 0) {
 812                         spin_unlock(&iosapic_lock);
 813                         spin_unlock_irqrestore(&irq_descp(vector)->lock,
 814                                                flags);
 815                         return err;
 816                 }
 817
 818                 /*
 819                  * If the vector is shared and already unmasked for
 820                  * other interrupt sources, don't mask it.
 821                  */
 822                 low32 = iosapic_intr_info[vector].low32;
 823                 if (vector_is_shared(vector) && !(low32 & IOSAPIC_MASK))
 824                         mask = 0;
 825                 set_rte(gsi, vector, dest, mask);
 826         }
 827         spin_unlock(&iosapic_lock);
 828         spin_unlock_irqrestore(&irq_descp(vector)->lock, flags);
 829
 830         printk(KERN_INFO "GSI %u (%s, %s) -> CPU %d (0x%04x) vector %d\n",
 831                gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
 832                (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
 833                cpu_logical_id(dest), dest, vector);
 834
 835         return vector;
 836 }
 837
 838 void
 839 iosapic_unregister_intr (unsigned int gsi)
 840 {
 841         unsigned long flags;
 842         int irq, vector, index;
 843         irq_desc_t *idesc;
 844         u32 low32;
 845         unsigned long trigger, polarity;
 846         unsigned int dest;
 847         struct iosapic_rte_info *rte;
 848
 849         /*
 850          * If the irq associated with the gsi is not found,
 851          * iosapic_unregister_intr() is unbalanced. We need to check
 852          * this again after getting locks.
 853          */
 854         irq = gsi_to_irq(gsi);
 855         if (irq < 0) {
 856                 printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n",
 857                        gsi);
 858                 WARN_ON(1);
 859                 return;
 860         }
 861         vector = irq_to_vector(irq);
 862
 863         idesc = irq_descp(irq);
 864         spin_lock_irqsave(&idesc->lock, flags);
 865         spin_lock(&iosapic_lock);
 866         {
 867                 if ((rte = gsi_vector_to_rte(gsi, vector)) == NULL) {
 868                         printk(KERN_ERR
 869                                "iosapic_unregister_intr(%u) unbalanced\n",
 870                                gsi);
 871                         WARN_ON(1);
 872                         goto out;
 873                 }
 874
 875                 if (--rte->refcnt > 0)
 876                         goto out;
 877
 878                 /* Mask the interrupt */
 879                 low32 = iosapic_intr_info[vector].low32 | IOSAPIC_MASK;
 880                 iosapic_write(rte->addr, IOSAPIC_RTE_LOW(rte->rte_index),
 881                               low32);
 882
 883                 /* Remove the rte entry from the list */
 884                 list_del(&rte->rte_list);
 885                 iosapic_intr_info[vector].count--;
 886                 iosapic_free_rte(rte);
 887                 index = find_iosapic(gsi);
 888                 iosapic_lists[index].rtes_inuse--;
 889                 WARN_ON(iosapic_lists[index].rtes_inuse < 0);
 890
 891                 trigger  = iosapic_intr_info[vector].trigger;
 892                 polarity = iosapic_intr_info[vector].polarity;
 893                 dest     = iosapic_intr_info[vector].dest;
 894                 printk(KERN_INFO
 895                        "GSI %u (%s, %s) -> CPU %d (0x%04x)"
 896                        " vector %d unregistered\n",
 897                        gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
 898                        (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
 899                        cpu_logical_id(dest), dest, vector);
 900
 901                 if (list_empty(&iosapic_intr_info[vector].rtes)) {
 902                         /* Sanity check */
 903                         BUG_ON(iosapic_intr_info[vector].count);
 904
 905                         /* Clear the interrupt controller descriptor */
 906                         idesc->handler = &no_irq_type;
 907
 908                         /* Clear the interrupt information */
 909                         memset(&iosapic_intr_info[vector], 0,
 910                                sizeof(struct iosapic_intr_info));
 911                         iosapic_intr_info[vector].low32 |= IOSAPIC_MASK;
 912                         INIT_LIST_HEAD(&iosapic_intr_info[vector].rtes);
 913
 914                         if (idesc->action) {
 915                                 printk(KERN_ERR
 916                                        "interrupt handlers still exist on"
 917                                        "IRQ %u\n", irq);
 918                                 WARN_ON(1);
 919                         }
 920
 921                         /* Free the interrupt vector */
 922                         free_irq_vector(vector);
 923                 }
 924         }
 925  out:
 926         spin_unlock(&iosapic_lock);
 927         spin_unlock_irqrestore(&idesc->lock, flags);
 928 }
 929
 930 /*
 931  * ACPI calls this when it finds an entry for a platform interrupt.
 932  */
 933 int __init
 934 iosapic_register_platform_intr (u32 int_type, unsigned int gsi,
 935                                 int iosapic_vector, u16 eid, u16 id,
 936                                 unsigned long polarity, unsigned long trigger)
 937 {
 938         static const char * const name[] = {"unknown", "PMI", "INIT", "CPEI"};
 939         unsigned char delivery;
 940         int vector, mask = 0;
 941         unsigned int dest = ((id << 8) | eid) & 0xffff;
 942
 943         switch (int_type) {
 944               case ACPI_INTERRUPT_PMI:
 945                 vector = iosapic_vector;
 946                 /*
 947                  * since PMI vector is alloc'd by FW(ACPI) not by kernel,
 948                  * we need to make sure the vector is available
 949                  */
 950                 iosapic_reassign_vector(vector);
 951                 delivery = IOSAPIC_PMI;
 952                 break;
 953               case ACPI_INTERRUPT_INIT:
 954                 vector = assign_irq_vector(AUTO_ASSIGN);
 955                 if (vector < 0)
 956                         panic("%s: out of interrupt vectors!\n", __FUNCTION__);
 957                 delivery = IOSAPIC_INIT;
 958                 break;
 959               case ACPI_INTERRUPT_CPEI:
 960                 vector = IA64_CPE_VECTOR;
 961                 delivery = IOSAPIC_LOWEST_PRIORITY;
 962                 mask = 1;
 963                 break;
 964               default:
 965                 printk(KERN_ERR "%s: invalid int type 0x%x\n", __FUNCTION__,
 966                        int_type);
 967                 return -1;
 968         }
 969
 970         register_intr(gsi, vector, delivery, polarity, trigger);
 971
 972         printk(KERN_INFO
 973                "PLATFORM int %s (0x%x): GSI %u (%s, %s) -> CPU %d (0x%04x)"
 974                " vector %d\n",
 975                int_type < ARRAY_SIZE(name) ? name[int_type] : "unknown",
 976                int_type, gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
 977                (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
 978                cpu_logical_id(dest), dest, vector);
 979
 980         set_rte(gsi, vector, dest, mask);
 981         return vector;
 982 }
 983
 984 /*
 985  * ACPI calls this when it finds an entry for a legacy ISA IRQ override.
 986  */
 987 void __init
 988 iosapic_override_isa_irq (unsigned int isa_irq, unsigned int gsi,
 989                           unsigned long polarity,
 990                           unsigned long trigger)
 991 {
 992         int vector;
 993         unsigned int dest = cpu_physical_id(smp_processor_id());
 994
 995         vector = isa_irq_to_vector(isa_irq);
 996
 997         register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY, polarity, trigger);
 998
 999         DBG("ISA: IRQ %u -> GSI %u (%s,%s) -> CPU %d (0x%04x) vector %d\n",
1000             isa_irq, gsi, trigger == IOSAPIC_EDGE ? "edge" : "level",
1001             polarity == IOSAPIC_POL_HIGH ? "high" : "low",
1002             cpu_logical_id(dest), dest, vector);
1003
1004         set_rte(gsi, vector, dest, 1);
1005 }
1006
1007 void __init
1008 iosapic_system_init (int system_pcat_compat)
1009 {
1010         int vector;
1011
1012         for (vector = 0; vector < IA64_NUM_VECTORS; ++vector) {
1013                 iosapic_intr_info[vector].low32 = IOSAPIC_MASK;
1014                 /* mark as unused */
1015                 INIT_LIST_HEAD(&iosapic_intr_info[vector].rtes);
1016         }
1017
1018         pcat_compat = system_pcat_compat;
1019         if (pcat_compat) {
1020                 /*
1021                  * Disable the compatibility mode interrupts (8259 style),
1022                  * needs IN/OUT support enabled.
1023                  */
1024                 printk(KERN_INFO
1025                        "%s: Disabling PC-AT compatible 8259 interrupts\n",
1026                        __FUNCTION__);
1027                 outb(0xff, 0xA1);
1028                 outb(0xff, 0x21);
1029         }
1030 }
1031
1032 static inline int
1033 iosapic_alloc (void)
1034 {
1035         int index;
1036
1037         for (index = 0; index < NR_IOSAPICS; index++)
1038                 if (!iosapic_lists[index].addr)
1039                         return index;
1040
1041         printk(KERN_WARNING "%s: failed to allocate iosapic\n", __FUNCTION__);
1042         return -1;
1043 }
1044
1045 static inline void
1046 iosapic_free (int index)
1047 {
1048         memset(&iosapic_lists[index], 0, sizeof(iosapic_lists[0]));
1049 }
1050
1051 static inline int
1052 iosapic_check_gsi_range (unsigned int gsi_base, unsigned int ver)
1053 {
1054         int index;
1055         unsigned int gsi_end, base, end;
1056
1057         /* check gsi range */
1058         gsi_end = gsi_base + ((ver >> 16) & 0xff);
1059         for (index = 0; index < NR_IOSAPICS; index++) {
1060                 if (!iosapic_lists[index].addr)
1061                         continue;
1062
1063                 base = iosapic_lists[index].gsi_base;
1064                 end  = base + iosapic_lists[index].num_rte - 1;
1065
1066                 if (gsi_end < base || end < gsi_base)
1067                         continue; /* OK */
1068
1069                 return -EBUSY;
1070         }
1071         return 0;
1072 }
1073
1074 int __devinit
1075 iosapic_init (unsigned long phys_addr, unsigned int gsi_base)
1076 {
1077         int num_rte, err, index;
1078         unsigned int isa_irq, ver;
1079         char __iomem *addr;
1080         unsigned long flags;
1081
1082         spin_lock_irqsave(&iosapic_lock, flags);
1083         {
1084                 addr = ioremap(phys_addr, 0);
1085                 ver = iosapic_version(addr);
1086
1087                 if ((err = iosapic_check_gsi_range(gsi_base, ver))) {
1088                         iounmap(addr);
1089                         spin_unlock_irqrestore(&iosapic_lock, flags);
1090                         return err;
1091                 }
1092
1093                 /*
1094                  * The MAX_REDIR register holds the highest input pin
1095                  * number (starting from 0).
1096                  * We add 1 so that we can use it for number of pins (= RTEs)
1097                  */
1098                 num_rte = ((ver >> 16) & 0xff) + 1;
1099
1100                 index = iosapic_alloc();
1101                 iosapic_lists[index].addr = addr;
1102                 iosapic_lists[index].gsi_base = gsi_base;
1103                 iosapic_lists[index].num_rte = num_rte;
1104 #ifdef CONFIG_NUMA
1105                 iosapic_lists[index].node = MAX_NUMNODES;
1106 #endif
1107         }
1108         spin_unlock_irqrestore(&iosapic_lock, flags);
1109
1110         if ((gsi_base == 0) && pcat_compat) {
1111                 /*
1112                  * Map the legacy ISA devices into the IOSAPIC data.  Some of
1113                  * these may get reprogrammed later on with data from the ACPI
1114                  * Interrupt Source Override table.
1115                  */
1116                 for (isa_irq = 0; isa_irq < 16; ++isa_irq)
1117                         iosapic_override_isa_irq(isa_irq, isa_irq,
1118                                                  IOSAPIC_POL_HIGH,
1119                                                  IOSAPIC_EDGE);
1120         }
1121         return 0;
1122 }
1123
1124 #ifdef CONFIG_HOTPLUG
1125 int
1126 iosapic_remove (unsigned int gsi_base)
1127 {
1128         int index, err = 0;
1129         unsigned long flags;
1130
1131         spin_lock_irqsave(&iosapic_lock, flags);
1132         {
1133                 index = find_iosapic(gsi_base);
1134                 if (index < 0) {
1135                         printk(KERN_WARNING "%s: No IOSAPIC for GSI base %u\n",
1136                                __FUNCTION__, gsi_base);
1137                         goto out;
1138                 }
1139
1140                 if (iosapic_lists[index].rtes_inuse) {
1141                         err = -EBUSY;
1142                         printk(KERN_WARNING
1143                                "%s: IOSAPIC for GSI base %u is busy\n",
1144                                __FUNCTION__, gsi_base);
1145                         goto out;
1146                 }
1147
1148                 iounmap(iosapic_lists[index].addr);
1149                 iosapic_free(index);
1150         }
1151  out:
1152         spin_unlock_irqrestore(&iosapic_lock, flags);
1153         return err;
1154 }
1155 #endif /* CONFIG_HOTPLUG */
1156
1157 #ifdef CONFIG_NUMA
1158 void __devinit
1159 map_iosapic_to_node(unsigned int gsi_base, int node)
1160 {
1161         int index;
1162
1163         index = find_iosapic(gsi_base);
1164         if (index < 0) {
1165                 printk(KERN_WARNING "%s: No IOSAPIC for GSI %u\n",
1166                        __FUNCTION__, gsi_base);
1167                 return;
1168         }
1169         iosapic_lists[index].node = node;
1170         return;
1171 }
1172 #endif
1173
1174 static int __init iosapic_enable_kmalloc (void)
1175 {
1176         iosapic_kmalloc_ok = 1;
1177         return 0;
1178 }
1179 core_initcall (iosapic_enable_kmalloc);