arch/powerpc/platforms/wsp/ics.c

   1 /*
   2  * Copyright 2008-2011 IBM Corporation.
   3  *
   4  *  This program is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU General Public License
   6  *  as published by the Free Software Foundation; either version
   7  *  2 of the License, or (at your option) any later version.
   8  */
   9
  10 #include <linux/cpu.h>
  11 #include <linux/init.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/irq.h>
  14 #include <linux/kernel.h>
  15 #include <linux/msi.h>
  16 #include <linux/of.h>
  17 #include <linux/slab.h>
  18 #include <linux/smp.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/types.h>
  21
  22 #include <asm/io.h>
  23 #include <asm/irq.h>
  24 #include <asm/xics.h>
  25
  26 #include "wsp.h"
  27 #include "ics.h"
  28
  29
  30 /* WSP ICS */
  31
  32 struct wsp_ics {
  33         struct ics ics;
  34         struct device_node *dn;
  35         void __iomem *regs;
  36         spinlock_t lock;
  37         unsigned long *bitmap;
  38         u32 chip_id;
  39         u32 lsi_base;
  40         u32 lsi_count;
  41         u64 hwirq_start;
  42         u64 count;
  43 #ifdef CONFIG_SMP
  44         int *hwirq_cpu_map;
  45 #endif
  46 };
  47
  48 #define to_wsp_ics(ics) container_of(ics, struct wsp_ics, ics)
  49
  50 #define INT_SRC_LAYER_BUID_REG(base)    ((base) + 0x00)
  51 #define IODA_TBL_ADDR_REG(base)         ((base) + 0x18)
  52 #define IODA_TBL_DATA_REG(base)         ((base) + 0x20)
  53 #define XIVE_UPDATE_REG(base)           ((base) + 0x28)
  54 #define ICS_INT_CAPS_REG(base)          ((base) + 0x30)
  55
  56 #define TBL_AUTO_INCREMENT      ((1UL << 63) | (1UL << 15))
  57 #define TBL_SELECT_XIST         (1UL << 48)
  58 #define TBL_SELECT_XIVT         (1UL << 49)
  59
  60 #define IODA_IRQ(irq)           ((irq) & (0x7FFULL))    /* HRM 5.1.3.4 */
  61
  62 #define XIST_REQUIRED           0x8
  63 #define XIST_REJECTED           0x4
  64 #define XIST_PRESENTED          0x2
  65 #define XIST_PENDING            0x1
  66
  67 #define XIVE_SERVER_SHIFT       42
  68 #define XIVE_SERVER_MASK        0xFFFFULL
  69 #define XIVE_PRIORITY_MASK      0xFFULL
  70 #define XIVE_PRIORITY_SHIFT     32
  71 #define XIVE_WRITE_ENABLE       (1ULL << 63)
  72
  73 /*
  74  * The docs refer to a 6 bit field called ChipID, which consists of a
  75  * 3 bit NodeID and a 3 bit ChipID. On WSP the ChipID is always zero
  76  * so we ignore it, and every where we use "chip id" in this code we
  77  * mean the NodeID.
  78  */
  79 #define WSP_ICS_CHIP_SHIFT              17
  80
  81
  82 static struct wsp_ics *ics_list;
  83 static int num_ics;
  84
  85 /* ICS Source controller accessors */
  86
  87 static u64 wsp_ics_get_xive(struct wsp_ics *ics, unsigned int irq)
  88 {
  89         unsigned long flags;
  90         u64 xive;
  91
  92         spin_lock_irqsave(&ics->lock, flags);
  93         out_be64(IODA_TBL_ADDR_REG(ics->regs), TBL_SELECT_XIVT | IODA_IRQ(irq));
  94         xive = in_be64(IODA_TBL_DATA_REG(ics->regs));
  95         spin_unlock_irqrestore(&ics->lock, flags);
  96
  97         return xive;
  98 }
  99
 100 static void wsp_ics_set_xive(struct wsp_ics *ics, unsigned int irq, u64 xive)
 101 {
 102         xive &= ~XIVE_ADDR_MASK;
 103         xive |= (irq & XIVE_ADDR_MASK);
 104         xive |= XIVE_WRITE_ENABLE;
 105
 106         out_be64(XIVE_UPDATE_REG(ics->regs), xive);
 107 }
 108
 109 static u64 xive_set_server(u64 xive, unsigned int server)
 110 {
 111         u64 mask = ~(XIVE_SERVER_MASK << XIVE_SERVER_SHIFT);
 112
 113         xive &= mask;
 114         xive |= (server & XIVE_SERVER_MASK) << XIVE_SERVER_SHIFT;
 115
 116         return xive;
 117 }
 118
 119 static u64 xive_set_priority(u64 xive, unsigned int priority)
 120 {
 121         u64 mask = ~(XIVE_PRIORITY_MASK << XIVE_PRIORITY_SHIFT);
 122
 123         xive &= mask;
 124         xive |= (priority & XIVE_PRIORITY_MASK) << XIVE_PRIORITY_SHIFT;
 125
 126         return xive;
 127 }
 128
 129
 130 #ifdef CONFIG_SMP
 131 /* Find logical CPUs within mask on a given chip and store result in ret */
 132 void cpus_on_chip(int chip_id, cpumask_t *mask, cpumask_t *ret)
 133 {
 134         int cpu, chip;
 135         struct device_node *cpu_dn, *dn;
 136         const u32 *prop;
 137
 138         cpumask_clear(ret);
 139         for_each_cpu(cpu, mask) {
 140                 cpu_dn = of_get_cpu_node(cpu, NULL);
 141                 if (!cpu_dn)
 142                         continue;
 143
 144                 prop = of_get_property(cpu_dn, "at-node", NULL);
 145                 if (!prop) {
 146                         of_node_put(cpu_dn);
 147                         continue;
 148                 }
 149
 150                 dn = of_find_node_by_phandle(*prop);
 151                 of_node_put(cpu_dn);
 152
 153                 chip = wsp_get_chip_id(dn);
 154                 if (chip == chip_id)
 155                         cpumask_set_cpu(cpu, ret);
 156
 157                 of_node_put(dn);
 158         }
 159 }
 160
 161 /* Store a suitable CPU to handle a hwirq in the ics->hwirq_cpu_map cache */
 162 static int cache_hwirq_map(struct wsp_ics *ics, unsigned int hwirq,
 163                            const cpumask_t *affinity)
 164 {
 165         cpumask_var_t avail, newmask;
 166         int ret = -ENOMEM, cpu, cpu_rover = 0, target;
 167         int index = hwirq - ics->hwirq_start;
 168         unsigned int nodeid;
 169
 170         BUG_ON(index < 0 || index >= ics->count);
 171
 172         if (!ics->hwirq_cpu_map)
 173                 return -ENOMEM;
 174
 175         if (!distribute_irqs) {
 176                 ics->hwirq_cpu_map[hwirq - ics->hwirq_start] = xics_default_server;
 177                 return 0;
 178         }
 179
 180         /* Allocate needed CPU masks */
 181         if (!alloc_cpumask_var(&avail, GFP_KERNEL))
 182                 goto ret;
 183         if (!alloc_cpumask_var(&newmask, GFP_KERNEL))
 184                 goto freeavail;
 185
 186         /* Find PBus attached to the source of this IRQ */
 187         nodeid = (hwirq >> WSP_ICS_CHIP_SHIFT) & 0x3; /* 12:14 */
 188
 189         /* Find CPUs that could handle this IRQ */
 190         if (affinity)
 191                 cpumask_and(avail, cpu_online_mask, affinity);
 192         else
 193                 cpumask_copy(avail, cpu_online_mask);
 194
 195         /* Narrow selection down to logical CPUs on the same chip */
 196         cpus_on_chip(nodeid, avail, newmask);
 197
 198         /* Ensure we haven't narrowed it down to 0 */
 199         if (unlikely(cpumask_empty(newmask))) {
 200                 if (unlikely(cpumask_empty(avail))) {
 201                         ret = -1;
 202                         goto out;
 203                 }
 204                 cpumask_copy(newmask, avail);
 205         }
 206
 207         /* Choose a CPU out of those we narrowed it down to in round robin */
 208         target = hwirq % cpumask_weight(newmask);
 209         for_each_cpu(cpu, newmask) {
 210                 if (cpu_rover++ >= target) {
 211                         ics->hwirq_cpu_map[index] = get_hard_smp_processor_id(cpu);
 212                         ret = 0;
 213                         goto out;
 214                 }
 215         }
 216
 217         /* Shouldn't happen */
 218         WARN_ON(1);
 219
 220 out:
 221         free_cpumask_var(newmask);
 222 freeavail:
 223         free_cpumask_var(avail);
 224 ret:
 225         if (ret < 0) {
 226                 ics->hwirq_cpu_map[index] = cpumask_first(cpu_online_mask);
 227                 pr_warning("Error, falling hwirq 0x%x routing back to CPU %i\n",
 228                            hwirq, ics->hwirq_cpu_map[index]);
 229         }
 230         return ret;
 231 }
 232
 233 static void alloc_irq_map(struct wsp_ics *ics)
 234 {
 235         int i;
 236
 237         ics->hwirq_cpu_map = kmalloc(sizeof(int) * ics->count, GFP_KERNEL);
 238         if (!ics->hwirq_cpu_map) {
 239                 pr_warning("Allocate hwirq_cpu_map failed, "
 240                            "IRQ balancing disabled\n");
 241                 return;
 242         }
 243
 244         for (i=0; i < ics->count; i++)
 245                 ics->hwirq_cpu_map[i] = xics_default_server;
 246 }
 247
 248 static int get_irq_server(struct wsp_ics *ics, unsigned int hwirq)
 249 {
 250         int index = hwirq - ics->hwirq_start;
 251
 252         BUG_ON(index < 0 || index >= ics->count);
 253
 254         if (!ics->hwirq_cpu_map)
 255                 return xics_default_server;
 256
 257         return ics->hwirq_cpu_map[index];
 258 }
 259 #else /* !CONFIG_SMP */
 260 static int cache_hwirq_map(struct wsp_ics *ics, unsigned int hwirq,
 261                            const cpumask_t *affinity)
 262 {
 263         return 0;
 264 }
 265
 266 static int get_irq_server(struct wsp_ics *ics, unsigned int hwirq)
 267 {
 268         return xics_default_server;
 269 }
 270
 271 static void alloc_irq_map(struct wsp_ics *ics) { }
 272 #endif
 273
 274 static void wsp_chip_unmask_irq(struct irq_data *d)
 275 {
 276         unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
 277         struct wsp_ics *ics;
 278         int server;
 279         u64 xive;
 280
 281         if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
 282                 return;
 283
 284         ics = d->chip_data;
 285         if (WARN_ON(!ics))
 286                 return;
 287
 288         server = get_irq_server(ics, hw_irq);
 289
 290         xive = wsp_ics_get_xive(ics, hw_irq);
 291         xive = xive_set_server(xive, server);
 292         xive = xive_set_priority(xive, DEFAULT_PRIORITY);
 293         wsp_ics_set_xive(ics, hw_irq, xive);
 294 }
 295
 296 static unsigned int wsp_chip_startup(struct irq_data *d)
 297 {
 298         /* unmask it */
 299         wsp_chip_unmask_irq(d);
 300         return 0;
 301 }
 302
 303 static void wsp_mask_real_irq(unsigned int hw_irq, struct wsp_ics *ics)
 304 {
 305         u64 xive;
 306
 307         if (hw_irq == XICS_IPI)
 308                 return;
 309
 310         if (WARN_ON(!ics))
 311                 return;
 312         xive = wsp_ics_get_xive(ics, hw_irq);
 313         xive = xive_set_server(xive, xics_default_server);
 314         xive = xive_set_priority(xive, LOWEST_PRIORITY);
 315         wsp_ics_set_xive(ics, hw_irq, xive);
 316 }
 317
 318 static void wsp_chip_mask_irq(struct irq_data *d)
 319 {
 320         unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
 321         struct wsp_ics *ics = d->chip_data;
 322
 323         if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
 324                 return;
 325
 326         wsp_mask_real_irq(hw_irq, ics);
 327 }
 328
 329 static int wsp_chip_set_affinity(struct irq_data *d,
 330                                  const struct cpumask *cpumask, bool force)
 331 {
 332         unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
 333         struct wsp_ics *ics;
 334         int ret;
 335         u64 xive;
 336
 337         if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
 338                 return -1;
 339
 340         ics = d->chip_data;
 341         if (WARN_ON(!ics))
 342                 return -1;
 343         xive = wsp_ics_get_xive(ics, hw_irq);
 344
 345         /*
 346          * For the moment only implement delivery to all cpus or one cpu.
 347          * Get current irq_server for the given irq
 348          */
 349         ret = cache_hwirq_map(ics, d->irq, cpumask);
 350         if (ret == -1) {
 351                 char cpulist[128];
 352                 cpumask_scnprintf(cpulist, sizeof(cpulist), cpumask);
 353                 pr_warning("%s: No online cpus in the mask %s for irq %d\n",
 354                            __func__, cpulist, d->irq);
 355                 return -1;
 356         } else if (ret == -ENOMEM) {
 357                 pr_warning("%s: Out of memory\n", __func__);
 358                 return -1;
 359         }
 360
 361         xive = xive_set_server(xive, get_irq_server(ics, hw_irq));
 362         wsp_ics_set_xive(ics, hw_irq, xive);
 363
 364         return 0;
 365 }
 366
 367 static struct irq_chip wsp_irq_chip = {
 368         .name = "WSP ICS",
 369         .irq_startup            = wsp_chip_startup,
 370         .irq_mask               = wsp_chip_mask_irq,
 371         .irq_unmask             = wsp_chip_unmask_irq,
 372         .irq_set_affinity       = wsp_chip_set_affinity
 373 };
 374
 375 static int wsp_ics_host_match(struct ics *ics, struct device_node *dn)
 376 {
 377         /* All ICSs in the system implement a global irq number space,
 378          * so match against them all. */
 379         return of_device_is_compatible(dn, "ibm,ppc-xics");
 380 }
 381
 382 static int wsp_ics_match_hwirq(struct wsp_ics *wsp_ics, unsigned int hwirq)
 383 {
 384         if (hwirq >= wsp_ics->hwirq_start &&
 385             hwirq <  wsp_ics->hwirq_start + wsp_ics->count)
 386                 return 1;
 387
 388         return 0;
 389 }
 390
 391 static int wsp_ics_map(struct ics *ics, unsigned int virq)
 392 {
 393         struct wsp_ics *wsp_ics = to_wsp_ics(ics);
 394         unsigned int hw_irq = virq_to_hw(virq);
 395         unsigned long flags;
 396
 397         if (!wsp_ics_match_hwirq(wsp_ics, hw_irq))
 398                 return -ENOENT;
 399
 400         irq_set_chip_and_handler(virq, &wsp_irq_chip, handle_fasteoi_irq);
 401
 402         irq_set_chip_data(virq, wsp_ics);
 403
 404         spin_lock_irqsave(&wsp_ics->lock, flags);
 405         bitmap_allocate_region(wsp_ics->bitmap, hw_irq - wsp_ics->hwirq_start, 0);
 406         spin_unlock_irqrestore(&wsp_ics->lock, flags);
 407
 408         return 0;
 409 }
 410
 411 static void wsp_ics_mask_unknown(struct ics *ics, unsigned long hw_irq)
 412 {
 413         struct wsp_ics *wsp_ics = to_wsp_ics(ics);
 414
 415         if (!wsp_ics_match_hwirq(wsp_ics, hw_irq))
 416                 return;
 417
 418         pr_err("%s: IRQ %lu (real) is invalid, disabling it.\n", __func__, hw_irq);
 419         wsp_mask_real_irq(hw_irq, wsp_ics);
 420 }
 421
 422 static long wsp_ics_get_server(struct ics *ics, unsigned long hw_irq)
 423 {
 424         struct wsp_ics *wsp_ics = to_wsp_ics(ics);
 425
 426         if (!wsp_ics_match_hwirq(wsp_ics, hw_irq))
 427                 return -ENOENT;
 428
 429         return get_irq_server(wsp_ics, hw_irq);
 430 }
 431
 432 /* HW Number allocation API */
 433
 434 static struct wsp_ics *wsp_ics_find_dn_ics(struct device_node *dn)
 435 {
 436         struct device_node *iparent;
 437         int i;
 438
 439         iparent = of_irq_find_parent(dn);
 440         if (!iparent) {
 441                 pr_err("wsp_ics: Failed to find interrupt parent!\n");
 442                 return NULL;
 443         }
 444
 445         for(i = 0; i < num_ics; i++) {
 446                 if(ics_list[i].dn == iparent)
 447                         break;
 448         }
 449
 450         if (i >= num_ics) {
 451                 pr_err("wsp_ics: Unable to find parent bitmap!\n");
 452                 return NULL;
 453         }
 454
 455         return &ics_list[i];
 456 }
 457
 458 int wsp_ics_alloc_irq(struct device_node *dn, int num)
 459 {
 460         struct wsp_ics *ics;
 461         int order, offset;
 462
 463         ics = wsp_ics_find_dn_ics(dn);
 464         if (!ics)
 465                 return -ENODEV;
 466
 467         /* Fast, but overly strict if num isn't a power of two */
 468         order = get_count_order(num);
 469
 470         spin_lock_irq(&ics->lock);
 471         offset = bitmap_find_free_region(ics->bitmap, ics->count, order);
 472         spin_unlock_irq(&ics->lock);
 473
 474         if (offset < 0)
 475                 return offset;
 476
 477         return offset + ics->hwirq_start;
 478 }
 479
 480 void wsp_ics_free_irq(struct device_node *dn, unsigned int irq)
 481 {
 482         struct wsp_ics *ics;
 483
 484         ics = wsp_ics_find_dn_ics(dn);
 485         if (WARN_ON(!ics))
 486                 return;
 487
 488         spin_lock_irq(&ics->lock);
 489         bitmap_release_region(ics->bitmap, irq, 0);
 490         spin_unlock_irq(&ics->lock);
 491 }
 492
 493 /* Initialisation */
 494
 495 static int __init wsp_ics_bitmap_setup(struct wsp_ics *ics,
 496                                       struct device_node *dn)
 497 {
 498         int len, i, j, size;
 499         u32 start, count;
 500         const u32 *p;
 501
 502         size = BITS_TO_LONGS(ics->count) * sizeof(long);
 503         ics->bitmap = kzalloc(size, GFP_KERNEL);
 504         if (!ics->bitmap) {
 505                 pr_err("wsp_ics: ENOMEM allocating IRQ bitmap!\n");
 506                 return -ENOMEM;
 507         }
 508
 509         spin_lock_init(&ics->lock);
 510
 511         p = of_get_property(dn, "available-ranges", &len);
 512         if (!p || !len) {
 513                 /* FIXME this should be a WARN() once mambo is updated */
 514                 pr_err("wsp_ics: No available-ranges defined for %s\n",
 515                         dn->full_name);
 516                 return 0;
 517         }
 518
 519         if (len % (2 * sizeof(u32)) != 0) {
 520                 /* FIXME this should be a WARN() once mambo is updated */
 521                 pr_err("wsp_ics: Invalid available-ranges for %s\n",
 522                         dn->full_name);
 523                 return 0;
 524         }
 525
 526         bitmap_fill(ics->bitmap, ics->count);
 527
 528         for (i = 0; i < len / sizeof(u32); i += 2) {
 529                 start = of_read_number(p + i, 1);
 530                 count = of_read_number(p + i + 1, 1);
 531
 532                 pr_devel("%s: start: %d count: %d\n", __func__, start, count);
 533
 534                 if ((start + count) > (ics->hwirq_start + ics->count) ||
 535                      start < ics->hwirq_start) {
 536                         pr_err("wsp_ics: Invalid range! -> %d to %d\n",
 537                                         start, start + count);
 538                         break;
 539                 }
 540
 541                 for (j = 0; j < count; j++)
 542                         bitmap_release_region(ics->bitmap,
 543                                 (start + j) - ics->hwirq_start, 0);
 544         }
 545
 546         /* Ensure LSIs are not available for allocation */
 547         bitmap_allocate_region(ics->bitmap, ics->lsi_base,
 548                                get_count_order(ics->lsi_count));
 549
 550         return 0;
 551 }
 552
 553 static int __init wsp_ics_setup(struct wsp_ics *ics, struct device_node *dn)
 554 {
 555         u32 lsi_buid, msi_buid, msi_base, msi_count;
 556         void __iomem *regs;
 557         const u32 *p;
 558         int rc, len, i;
 559         u64 caps, buid;
 560
 561         p = of_get_property(dn, "interrupt-ranges", &len);
 562         if (!p || len < (2 * sizeof(u32))) {
 563                 pr_err("wsp_ics: No/bad interrupt-ranges found on %s\n",
 564                         dn->full_name);
 565                 return -ENOENT;
 566         }
 567
 568         if (len > (2 * sizeof(u32))) {
 569                 pr_err("wsp_ics: Multiple ics ranges not supported.\n");
 570                 return -EINVAL;
 571         }
 572
 573         regs = of_iomap(dn, 0);
 574         if (!regs) {
 575                 pr_err("wsp_ics: of_iomap(%s) failed\n", dn->full_name);
 576                 return -ENXIO;
 577         }
 578
 579         ics->hwirq_start = of_read_number(p, 1);
 580         ics->count = of_read_number(p + 1, 1);
 581         ics->regs = regs;
 582
 583         ics->chip_id = wsp_get_chip_id(dn);
 584         if (WARN_ON(ics->chip_id < 0))
 585                 ics->chip_id = 0;
 586
 587         /* Get some informations about the critter */
 588         caps = in_be64(ICS_INT_CAPS_REG(ics->regs));
 589         buid = in_be64(INT_SRC_LAYER_BUID_REG(ics->regs));
 590         ics->lsi_count = caps >> 56;
 591         msi_count = (caps >> 44) & 0x7ff;
 592
 593         /* Note: LSI BUID is 9 bits, but really only 3 are BUID and the
 594          * rest is mixed in the interrupt number. We store the whole
 595          * thing though
 596          */
 597         lsi_buid = (buid >> 48) & 0x1ff;
 598         ics->lsi_base = (ics->chip_id << WSP_ICS_CHIP_SHIFT) | lsi_buid << 5;
 599         msi_buid = (buid >> 37) & 0x7;
 600         msi_base = (ics->chip_id << WSP_ICS_CHIP_SHIFT) | msi_buid << 11;
 601
 602         pr_info("wsp_ics: Found %s\n", dn->full_name);
 603         pr_info("wsp_ics:    irq range : 0x%06llx..0x%06llx\n",
 604                 ics->hwirq_start, ics->hwirq_start + ics->count - 1);
 605         pr_info("wsp_ics:    %4d LSIs : 0x%06x..0x%06x\n",
 606                 ics->lsi_count, ics->lsi_base,
 607                 ics->lsi_base + ics->lsi_count - 1);
 608         pr_info("wsp_ics:    %4d MSIs : 0x%06x..0x%06x\n",
 609                 msi_count, msi_base,
 610                 msi_base + msi_count - 1);
 611
 612         /* Let's check the HW config is sane */
 613         if (ics->lsi_base < ics->hwirq_start ||
 614             (ics->lsi_base + ics->lsi_count) > (ics->hwirq_start + ics->count))
 615                 pr_warning("wsp_ics: WARNING ! LSIs out of interrupt-ranges !\n");
 616         if (msi_base < ics->hwirq_start ||
 617             (msi_base + msi_count) > (ics->hwirq_start + ics->count))
 618                 pr_warning("wsp_ics: WARNING ! MSIs out of interrupt-ranges !\n");
 619
 620         /* We don't check for overlap between LSI and MSI, which will happen
 621          * if we use the same BUID, I'm not sure yet how legit that is.
 622          */
 623
 624         rc = wsp_ics_bitmap_setup(ics, dn);
 625         if (rc) {
 626                 iounmap(regs);
 627                 return rc;
 628         }
 629
 630         ics->dn = of_node_get(dn);
 631         alloc_irq_map(ics);
 632
 633         for(i = 0; i < ics->count; i++)
 634                 wsp_mask_real_irq(ics->hwirq_start + i, ics);
 635
 636         ics->ics.map = wsp_ics_map;
 637         ics->ics.mask_unknown = wsp_ics_mask_unknown;
 638         ics->ics.get_server = wsp_ics_get_server;
 639         ics->ics.host_match = wsp_ics_host_match;
 640
 641         xics_register_ics(&ics->ics);
 642
 643         return 0;
 644 }
 645
 646 static void __init wsp_ics_set_default_server(void)
 647 {
 648         struct device_node *np;
 649         u32 hwid;
 650
 651         /* Find the server number for the boot cpu. */
 652         np = of_get_cpu_node(boot_cpuid, NULL);
 653         BUG_ON(!np);
 654
 655         hwid = get_hard_smp_processor_id(boot_cpuid);
 656
 657         pr_info("wsp_ics: default server is %#x, CPU %s\n", hwid, np->full_name);
 658         xics_default_server = hwid;
 659
 660         of_node_put(np);
 661 }
 662
 663 static int __init wsp_ics_init(void)
 664 {
 665         struct device_node *dn;
 666         struct wsp_ics *ics;
 667         int rc, found;
 668
 669         wsp_ics_set_default_server();
 670
 671         found = 0;
 672         for_each_compatible_node(dn, NULL, "ibm,ppc-xics")
 673                 found++;
 674
 675         if (found == 0) {
 676                 pr_err("wsp_ics: No ICS's found!\n");
 677                 return -ENODEV;
 678         }
 679
 680         ics_list = kmalloc(sizeof(*ics) * found, GFP_KERNEL);
 681         if (!ics_list) {
 682                 pr_err("wsp_ics: No memory for structs.\n");
 683                 return -ENOMEM;
 684         }
 685
 686         num_ics = 0;
 687         ics = ics_list;
 688         for_each_compatible_node(dn, NULL, "ibm,wsp-xics") {
 689                 rc = wsp_ics_setup(ics, dn);
 690                 if (rc == 0) {
 691                         ics++;
 692                         num_ics++;
 693                 }
 694         }
 695
 696         if (found != num_ics) {
 697                 pr_err("wsp_ics: Failed setting up %d ICS's\n",
 698                         found - num_ics);
 699                 return -1;
 700         }
 701
 702         return 0;
 703 }
 704
 705 void __init wsp_init_irq(void)
 706 {
 707         wsp_ics_init();
 708         xics_init();
 709
 710         /* We need to patch our irq chip's EOI to point to the right ICP */
 711         wsp_irq_chip.irq_eoi = icp_ops->eoi;
 712 }