arch/ia64/kernel/iosapic.c

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