arch/powerpc/platforms/pseries/xics.c

   1 /*
   2  * arch/powerpc/platforms/pseries/xics.c
   3  *
   4  * Copyright 2000 IBM Corporation.
   5  *
   6  *  This program is free software; you can redistribute it and/or
   7  *  modify it under the terms of the GNU General Public License
   8  *  as published by the Free Software Foundation; either version
   9  *  2 of the License, or (at your option) any later version.
  10  */
  11
  12 #undef DEBUG
  13
  14 #include <linux/types.h>
  15 #include <linux/threads.h>
  16 #include <linux/kernel.h>
  17 #include <linux/irq.h>
  18 #include <linux/smp.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/signal.h>
  21 #include <linux/init.h>
  22 #include <linux/gfp.h>
  23 #include <linux/radix-tree.h>
  24 #include <linux/cpu.h>
  25
  26 #include <asm/firmware.h>
  27 #include <asm/prom.h>
  28 #include <asm/io.h>
  29 #include <asm/pgtable.h>
  30 #include <asm/smp.h>
  31 #include <asm/rtas.h>
  32 #include <asm/hvcall.h>
  33 #include <asm/machdep.h>
  34 #include <asm/i8259.h>
  35
  36 #include "xics.h"
  37
  38 #define XICS_IPI                2
  39 #define XICS_IRQ_SPURIOUS       0
  40
  41 /* Want a priority other than 0.  Various HW issues require this. */
  42 #define DEFAULT_PRIORITY        5
  43
  44 /*
  45  * Mark IPIs as higher priority so we can take them inside interrupts that
  46  * arent marked IRQF_DISABLED
  47  */
  48 #define IPI_PRIORITY            4
  49
  50 struct xics_ipl {
  51         union {
  52                 u32 word;
  53                 u8 bytes[4];
  54         } xirr_poll;
  55         union {
  56                 u32 word;
  57                 u8 bytes[4];
  58         } xirr;
  59         u32 dummy;
  60         union {
  61                 u32 word;
  62                 u8 bytes[4];
  63         } qirr;
  64 };
  65
  66 static struct xics_ipl __iomem *xics_per_cpu[NR_CPUS];
  67
  68 static unsigned int default_server = 0xFF;
  69 static unsigned int default_distrib_server = 0;
  70 static unsigned int interrupt_server_size = 8;
  71
  72 static struct irq_host *xics_host;
  73
  74 /*
  75  * XICS only has a single IPI, so encode the messages per CPU
  76  */
  77 struct xics_ipi_struct xics_ipi_message[NR_CPUS] __cacheline_aligned;
  78
  79 /* RTAS service tokens */
  80 static int ibm_get_xive;
  81 static int ibm_set_xive;
  82 static int ibm_int_on;
  83 static int ibm_int_off;
  84
  85
  86 /* Direct HW low level accessors */
  87
  88
  89 static inline unsigned int direct_xirr_info_get(int n_cpu)
  90 {
  91         return in_be32(&xics_per_cpu[n_cpu]->xirr.word);
  92 }
  93
  94 static inline void direct_xirr_info_set(int n_cpu, int value)
  95 {
  96         out_be32(&xics_per_cpu[n_cpu]->xirr.word, value);
  97 }
  98
  99 static inline void direct_cppr_info(int n_cpu, u8 value)
 100 {
 101         out_8(&xics_per_cpu[n_cpu]->xirr.bytes[0], value);
 102 }
 103
 104 static inline void direct_qirr_info(int n_cpu, u8 value)
 105 {
 106         out_8(&xics_per_cpu[n_cpu]->qirr.bytes[0], value);
 107 }
 108
 109
 110 /* LPAR low level accessors */
 111
 112
 113 static inline long plpar_eoi(unsigned long xirr)
 114 {
 115         return plpar_hcall_norets(H_EOI, xirr);
 116 }
 117
 118 static inline long plpar_cppr(unsigned long cppr)
 119 {
 120         return plpar_hcall_norets(H_CPPR, cppr);
 121 }
 122
 123 static inline long plpar_ipi(unsigned long servernum, unsigned long mfrr)
 124 {
 125         return plpar_hcall_norets(H_IPI, servernum, mfrr);
 126 }
 127
 128 static inline long plpar_xirr(unsigned long *xirr_ret)
 129 {
 130         unsigned long dummy;
 131         return plpar_hcall(H_XIRR, 0, 0, 0, 0, xirr_ret, &dummy, &dummy);
 132 }
 133
 134 static inline unsigned int lpar_xirr_info_get(int n_cpu)
 135 {
 136         unsigned long lpar_rc;
 137         unsigned long return_value;
 138
 139         lpar_rc = plpar_xirr(&return_value);
 140         if (lpar_rc != H_SUCCESS)
 141                 panic(" bad return code xirr - rc = %lx \n", lpar_rc);
 142         return (unsigned int)return_value;
 143 }
 144
 145 static inline void lpar_xirr_info_set(int n_cpu, int value)
 146 {
 147         unsigned long lpar_rc;
 148         unsigned long val64 = value & 0xffffffff;
 149
 150         lpar_rc = plpar_eoi(val64);
 151         if (lpar_rc != H_SUCCESS)
 152                 panic("bad return code EOI - rc = %ld, value=%lx\n", lpar_rc,
 153                       val64);
 154 }
 155
 156 static inline void lpar_cppr_info(int n_cpu, u8 value)
 157 {
 158         unsigned long lpar_rc;
 159
 160         lpar_rc = plpar_cppr(value);
 161         if (lpar_rc != H_SUCCESS)
 162                 panic("bad return code cppr - rc = %lx\n", lpar_rc);
 163 }
 164
 165 static inline void lpar_qirr_info(int n_cpu , u8 value)
 166 {
 167         unsigned long lpar_rc;
 168
 169         lpar_rc = plpar_ipi(get_hard_smp_processor_id(n_cpu), value);
 170         if (lpar_rc != H_SUCCESS)
 171                 panic("bad return code qirr - rc = %lx\n", lpar_rc);
 172 }
 173
 174
 175 /* High level handlers and init code */
 176
 177
 178 #ifdef CONFIG_SMP
 179 static int get_irq_server(unsigned int virq)
 180 {
 181         unsigned int server;
 182         /* For the moment only implement delivery to all cpus or one cpu */
 183         cpumask_t cpumask = irq_desc[virq].affinity;
 184         cpumask_t tmp = CPU_MASK_NONE;
 185
 186         if (!distribute_irqs)
 187                 return default_server;
 188
 189         if (cpus_equal(cpumask, CPU_MASK_ALL)) {
 190                 server = default_distrib_server;
 191         } else {
 192                 cpus_and(tmp, cpu_online_map, cpumask);
 193
 194                 if (cpus_empty(tmp))
 195                         server = default_distrib_server;
 196                 else
 197                         server = get_hard_smp_processor_id(first_cpu(tmp));
 198         }
 199
 200         return server;
 201
 202 }
 203 #else
 204 static int get_irq_server(unsigned int virq)
 205 {
 206         return default_server;
 207 }
 208 #endif
 209
 210
 211 static void xics_unmask_irq(unsigned int virq)
 212 {
 213         unsigned int irq;
 214         int call_status;
 215         unsigned int server;
 216
 217         pr_debug("xics: unmask virq %d\n", virq);
 218
 219         irq = (unsigned int)irq_map[virq].hwirq;
 220         pr_debug(" -> map to hwirq 0x%x\n", irq);
 221         if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
 222                 return;
 223
 224         server = get_irq_server(virq);
 225
 226         call_status = rtas_call(ibm_set_xive, 3, 1, NULL, irq, server,
 227                                 DEFAULT_PRIORITY);
 228         if (call_status != 0) {
 229                 printk(KERN_ERR "xics_enable_irq: irq=%u: ibm_set_xive "
 230                        "returned %d\n", irq, call_status);
 231                 printk("set_xive %x, server %x\n", ibm_set_xive, server);
 232                 return;
 233         }
 234
 235         /* Now unmask the interrupt (often a no-op) */
 236         call_status = rtas_call(ibm_int_on, 1, 1, NULL, irq);
 237         if (call_status != 0) {
 238                 printk(KERN_ERR "xics_enable_irq: irq=%u: ibm_int_on "
 239                        "returned %d\n", irq, call_status);
 240                 return;
 241         }
 242 }
 243
 244 static void xics_mask_real_irq(unsigned int irq)
 245 {
 246         int call_status;
 247         unsigned int server;
 248
 249         if (irq == XICS_IPI)
 250                 return;
 251
 252         call_status = rtas_call(ibm_int_off, 1, 1, NULL, irq);
 253         if (call_status != 0) {
 254                 printk(KERN_ERR "xics_disable_real_irq: irq=%u: "
 255                        "ibm_int_off returned %d\n", irq, call_status);
 256                 return;
 257         }
 258
 259         server = get_irq_server(irq);
 260         /* Have to set XIVE to 0xff to be able to remove a slot */
 261         call_status = rtas_call(ibm_set_xive, 3, 1, NULL, irq, server, 0xff);
 262         if (call_status != 0) {
 263                 printk(KERN_ERR "xics_disable_irq: irq=%u: ibm_set_xive(0xff)"
 264                        " returned %d\n", irq, call_status);
 265                 return;
 266         }
 267 }
 268
 269 static void xics_mask_irq(unsigned int virq)
 270 {
 271         unsigned int irq;
 272
 273         pr_debug("xics: mask virq %d\n", virq);
 274
 275         irq = (unsigned int)irq_map[virq].hwirq;
 276         if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
 277                 return;
 278         xics_mask_real_irq(irq);
 279 }
 280
 281 static unsigned int xics_startup(unsigned int virq)
 282 {
 283         unsigned int irq;
 284
 285         /* force a reverse mapping of the interrupt so it gets in the cache */
 286         irq = (unsigned int)irq_map[virq].hwirq;
 287         irq_radix_revmap(xics_host, irq);
 288
 289         /* unmask it */
 290         xics_unmask_irq(virq);
 291         return 0;
 292 }
 293
 294 static void xics_eoi_direct(unsigned int virq)
 295 {
 296         int cpu = smp_processor_id();
 297         unsigned int irq = (unsigned int)irq_map[virq].hwirq;
 298
 299         iosync();
 300         direct_xirr_info_set(cpu, (0xff << 24) | irq);
 301 }
 302
 303
 304 static void xics_eoi_lpar(unsigned int virq)
 305 {
 306         int cpu = smp_processor_id();
 307         unsigned int irq = (unsigned int)irq_map[virq].hwirq;
 308
 309         iosync();
 310         lpar_xirr_info_set(cpu, (0xff << 24) | irq);
 311 }
 312
 313 static inline unsigned int xics_remap_irq(unsigned int vec)
 314 {
 315         unsigned int irq;
 316
 317         vec &= 0x00ffffff;
 318
 319         if (vec == XICS_IRQ_SPURIOUS)
 320                 return NO_IRQ;
 321         irq = irq_radix_revmap(xics_host, vec);
 322         if (likely(irq != NO_IRQ))
 323                 return irq;
 324
 325         printk(KERN_ERR "Interrupt %u (real) is invalid,"
 326                " disabling it.\n", vec);
 327         xics_mask_real_irq(vec);
 328         return NO_IRQ;
 329 }
 330
 331 static unsigned int xics_get_irq_direct(struct pt_regs *regs)
 332 {
 333         unsigned int cpu = smp_processor_id();
 334
 335         return xics_remap_irq(direct_xirr_info_get(cpu));
 336 }
 337
 338 static unsigned int xics_get_irq_lpar(struct pt_regs *regs)
 339 {
 340         unsigned int cpu = smp_processor_id();
 341
 342         return xics_remap_irq(lpar_xirr_info_get(cpu));
 343 }
 344
 345 #ifdef CONFIG_SMP
 346
 347 static irqreturn_t xics_ipi_dispatch(int cpu, struct pt_regs *regs)
 348 {
 349         WARN_ON(cpu_is_offline(cpu));
 350
 351         while (xics_ipi_message[cpu].value) {
 352                 if (test_and_clear_bit(PPC_MSG_CALL_FUNCTION,
 353                                        &xics_ipi_message[cpu].value)) {
 354                         mb();
 355                         smp_message_recv(PPC_MSG_CALL_FUNCTION, regs);
 356                 }
 357                 if (test_and_clear_bit(PPC_MSG_RESCHEDULE,
 358                                        &xics_ipi_message[cpu].value)) {
 359                         mb();
 360                         smp_message_recv(PPC_MSG_RESCHEDULE, regs);
 361                 }
 362 #if 0
 363                 if (test_and_clear_bit(PPC_MSG_MIGRATE_TASK,
 364                                        &xics_ipi_message[cpu].value)) {
 365                         mb();
 366                         smp_message_recv(PPC_MSG_MIGRATE_TASK, regs);
 367                 }
 368 #endif
 369 #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
 370                 if (test_and_clear_bit(PPC_MSG_DEBUGGER_BREAK,
 371                                        &xics_ipi_message[cpu].value)) {
 372                         mb();
 373                         smp_message_recv(PPC_MSG_DEBUGGER_BREAK, regs);
 374                 }
 375 #endif
 376         }
 377         return IRQ_HANDLED;
 378 }
 379
 380 static irqreturn_t xics_ipi_action_direct(int irq, void *dev_id, struct pt_regs *regs)
 381 {
 382         int cpu = smp_processor_id();
 383
 384         direct_qirr_info(cpu, 0xff);
 385
 386         return xics_ipi_dispatch(cpu, regs);
 387 }
 388
 389 static irqreturn_t xics_ipi_action_lpar(int irq, void *dev_id, struct pt_regs *regs)
 390 {
 391         int cpu = smp_processor_id();
 392
 393         lpar_qirr_info(cpu, 0xff);
 394
 395         return xics_ipi_dispatch(cpu, regs);
 396 }
 397
 398 void xics_cause_IPI(int cpu)
 399 {
 400         if (firmware_has_feature(FW_FEATURE_LPAR))
 401                 lpar_qirr_info(cpu, IPI_PRIORITY);
 402         else
 403                 direct_qirr_info(cpu, IPI_PRIORITY);
 404 }
 405
 406 #endif /* CONFIG_SMP */
 407
 408 static void xics_set_cpu_priority(int cpu, unsigned char cppr)
 409 {
 410         if (firmware_has_feature(FW_FEATURE_LPAR))
 411                 lpar_cppr_info(cpu, cppr);
 412         else
 413                 direct_cppr_info(cpu, cppr);
 414         iosync();
 415 }
 416
 417 static void xics_set_affinity(unsigned int virq, cpumask_t cpumask)
 418 {
 419         unsigned int irq;
 420         int status;
 421         int xics_status[2];
 422         unsigned long newmask;
 423         cpumask_t tmp = CPU_MASK_NONE;
 424
 425         irq = (unsigned int)irq_map[virq].hwirq;
 426         if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
 427                 return;
 428
 429         status = rtas_call(ibm_get_xive, 1, 3, xics_status, irq);
 430
 431         if (status) {
 432                 printk(KERN_ERR "xics_set_affinity: irq=%u ibm,get-xive "
 433                        "returns %d\n", irq, status);
 434                 return;
 435         }
 436
 437         /* For the moment only implement delivery to all cpus or one cpu */
 438         if (cpus_equal(cpumask, CPU_MASK_ALL)) {
 439                 newmask = default_distrib_server;
 440         } else {
 441                 cpus_and(tmp, cpu_online_map, cpumask);
 442                 if (cpus_empty(tmp))
 443                         return;
 444                 newmask = get_hard_smp_processor_id(first_cpu(tmp));
 445         }
 446
 447         status = rtas_call(ibm_set_xive, 3, 1, NULL,
 448                                 irq, newmask, xics_status[1]);
 449
 450         if (status) {
 451                 printk(KERN_ERR "xics_set_affinity: irq=%u ibm,set-xive "
 452                        "returns %d\n", irq, status);
 453                 return;
 454         }
 455 }
 456
 457 void xics_setup_cpu(void)
 458 {
 459         int cpu = smp_processor_id();
 460
 461         xics_set_cpu_priority(cpu, 0xff);
 462
 463         /*
 464          * Put the calling processor into the GIQ.  This is really only
 465          * necessary from a secondary thread as the OF start-cpu interface
 466          * performs this function for us on primary threads.
 467          *
 468          * XXX: undo of teardown on kexec needs this too, as may hotplug
 469          */
 470         rtas_set_indicator(GLOBAL_INTERRUPT_QUEUE,
 471                 (1UL << interrupt_server_size) - 1 - default_distrib_server, 1);
 472 }
 473
 474
 475 static struct irq_chip xics_pic_direct = {
 476         .typename = " XICS     ",
 477         .startup = xics_startup,
 478         .mask = xics_mask_irq,
 479         .unmask = xics_unmask_irq,
 480         .eoi = xics_eoi_direct,
 481         .set_affinity = xics_set_affinity
 482 };
 483
 484
 485 static struct irq_chip xics_pic_lpar = {
 486         .typename = " XICS     ",
 487         .startup = xics_startup,
 488         .mask = xics_mask_irq,
 489         .unmask = xics_unmask_irq,
 490         .eoi = xics_eoi_lpar,
 491         .set_affinity = xics_set_affinity
 492 };
 493
 494
 495 static int xics_host_match(struct irq_host *h, struct device_node *node)
 496 {
 497         /* IBM machines have interrupt parents of various funky types for things
 498          * like vdevices, events, etc... The trick we use here is to match
 499          * everything here except the legacy 8259 which is compatible "chrp,iic"
 500          */
 501         return !device_is_compatible(node, "chrp,iic");
 502 }
 503
 504 static int xics_host_map_direct(struct irq_host *h, unsigned int virq,
 505                                 irq_hw_number_t hw)
 506 {
 507         pr_debug("xics: map_direct virq %d, hwirq 0x%lx\n", virq, hw);
 508
 509         get_irq_desc(virq)->status |= IRQ_LEVEL;
 510         set_irq_chip_and_handler(virq, &xics_pic_direct, handle_fasteoi_irq);
 511         return 0;
 512 }
 513
 514 static int xics_host_map_lpar(struct irq_host *h, unsigned int virq,
 515                               irq_hw_number_t hw)
 516 {
 517         pr_debug("xics: map_direct virq %d, hwirq 0x%lx\n", virq, hw);
 518
 519         get_irq_desc(virq)->status |= IRQ_LEVEL;
 520         set_irq_chip_and_handler(virq, &xics_pic_lpar, handle_fasteoi_irq);
 521         return 0;
 522 }
 523
 524 static int xics_host_xlate(struct irq_host *h, struct device_node *ct,
 525                            u32 *intspec, unsigned int intsize,
 526                            irq_hw_number_t *out_hwirq, unsigned int *out_flags)
 527
 528 {
 529         /* Current xics implementation translates everything
 530          * to level. It is not technically right for MSIs but this
 531          * is irrelevant at this point. We might get smarter in the future
 532          */
 533         *out_hwirq = intspec[0];
 534         *out_flags = IRQ_TYPE_LEVEL_LOW;
 535
 536         return 0;
 537 }
 538
 539 static struct irq_host_ops xics_host_direct_ops = {
 540         .match = xics_host_match,
 541         .map = xics_host_map_direct,
 542         .xlate = xics_host_xlate,
 543 };
 544
 545 static struct irq_host_ops xics_host_lpar_ops = {
 546         .match = xics_host_match,
 547         .map = xics_host_map_lpar,
 548         .xlate = xics_host_xlate,
 549 };
 550
 551 static void __init xics_init_host(void)
 552 {
 553         struct irq_host_ops *ops;
 554
 555         if (firmware_has_feature(FW_FEATURE_LPAR))
 556                 ops = &xics_host_lpar_ops;
 557         else
 558                 ops = &xics_host_direct_ops;
 559         xics_host = irq_alloc_host(IRQ_HOST_MAP_TREE, 0, ops,
 560                                    XICS_IRQ_SPURIOUS);
 561         BUG_ON(xics_host == NULL);
 562         irq_set_default_host(xics_host);
 563 }
 564
 565 static void __init xics_map_one_cpu(int hw_id, unsigned long addr,
 566                                      unsigned long size)
 567 {
 568 #ifdef CONFIG_SMP
 569         int i;
 570
 571         /* This may look gross but it's good enough for now, we don't quite
 572          * have a hard -> linux processor id matching.
 573          */
 574         for_each_possible_cpu(i) {
 575                 if (!cpu_present(i))
 576                         continue;
 577                 if (hw_id == get_hard_smp_processor_id(i)) {
 578                         xics_per_cpu[i] = ioremap(addr, size);
 579                         return;
 580                 }
 581         }
 582 #else
 583         if (hw_id != 0)
 584                 return;
 585         xics_per_cpu[0] = ioremap(addr, size);
 586 #endif /* CONFIG_SMP */
 587 }
 588
 589 static void __init xics_init_one_node(struct device_node *np,
 590                                       unsigned int *indx)
 591 {
 592         unsigned int ilen;
 593         u32 *ireg;
 594
 595         /* This code does the theorically broken assumption that the interrupt
 596          * server numbers are the same as the hard CPU numbers.
 597          * This happens to be the case so far but we are playing with fire...
 598          * should be fixed one of these days. -BenH.
 599          */
 600         ireg = (u32 *)get_property(np, "ibm,interrupt-server-ranges", NULL);
 601
 602         /* Do that ever happen ? we'll know soon enough... but even good'old
 603          * f80 does have that property ..
 604          */
 605         WARN_ON(ireg == NULL);
 606         if (ireg) {
 607                 /*
 608                  * set node starting index for this node
 609                  */
 610                 *indx = *ireg;
 611         }
 612         ireg = (u32 *)get_property(np, "reg", &ilen);
 613         if (!ireg)
 614                 panic("xics_init_IRQ: can't find interrupt reg property");
 615
 616         while (ilen >= (4 * sizeof(u32))) {
 617                 unsigned long addr, size;
 618
 619                 /* XXX Use proper OF parsing code here !!! */
 620                 addr = (unsigned long)*ireg++ << 32;
 621                 ilen -= sizeof(u32);
 622                 addr |= *ireg++;
 623                 ilen -= sizeof(u32);
 624                 size = (unsigned long)*ireg++ << 32;
 625                 ilen -= sizeof(u32);
 626                 size |= *ireg++;
 627                 ilen -= sizeof(u32);
 628                 xics_map_one_cpu(*indx, addr, size);
 629                 (*indx)++;
 630         }
 631 }
 632
 633
 634 static void __init xics_setup_8259_cascade(void)
 635 {
 636         struct device_node *np, *old, *found = NULL;
 637         int cascade, naddr;
 638         u32 *addrp;
 639         unsigned long intack = 0;
 640
 641         for_each_node_by_type(np, "interrupt-controller")
 642                 if (device_is_compatible(np, "chrp,iic")) {
 643                         found = np;
 644                         break;
 645                 }
 646         if (found == NULL) {
 647                 printk(KERN_DEBUG "xics: no ISA interrupt controller\n");
 648                 return;
 649         }
 650         cascade = irq_of_parse_and_map(found, 0);
 651         if (cascade == NO_IRQ) {
 652                 printk(KERN_ERR "xics: failed to map cascade interrupt");
 653                 return;
 654         }
 655         pr_debug("xics: cascade mapped to irq %d\n", cascade);
 656
 657         for (old = of_node_get(found); old != NULL ; old = np) {
 658                 np = of_get_parent(old);
 659                 of_node_put(old);
 660                 if (np == NULL)
 661                         break;
 662                 if (strcmp(np->name, "pci") != 0)
 663                         continue;
 664                 addrp = (u32 *)get_property(np, "8259-interrupt-acknowledge", NULL);
 665                 if (addrp == NULL)
 666                         continue;
 667                 naddr = prom_n_addr_cells(np);
 668                 intack = addrp[naddr-1];
 669                 if (naddr > 1)
 670                         intack |= ((unsigned long)addrp[naddr-2]) << 32;
 671         }
 672         if (intack)
 673                 printk(KERN_DEBUG "xics: PCI 8259 intack at 0x%016lx\n", intack);
 674         i8259_init(found, intack);
 675         of_node_put(found);
 676         set_irq_chained_handler(cascade, pseries_8259_cascade);
 677 }
 678
 679 void __init xics_init_IRQ(void)
 680 {
 681         int i;
 682         struct device_node *np;
 683         u32 *ireg, ilen, indx = 0;
 684         int found = 0;
 685
 686         ppc64_boot_msg(0x20, "XICS Init");
 687
 688         ibm_get_xive = rtas_token("ibm,get-xive");
 689         ibm_set_xive = rtas_token("ibm,set-xive");
 690         ibm_int_on  = rtas_token("ibm,int-on");
 691         ibm_int_off = rtas_token("ibm,int-off");
 692
 693         for_each_node_by_type(np, "PowerPC-External-Interrupt-Presentation") {
 694                 found = 1;
 695                 if (firmware_has_feature(FW_FEATURE_LPAR))
 696                         break;
 697                 xics_init_one_node(np, &indx);
 698         }
 699         if (found == 0)
 700                 return;
 701
 702         xics_init_host();
 703
 704         /* Find the server numbers for the boot cpu. */
 705         for (np = of_find_node_by_type(NULL, "cpu");
 706              np;
 707              np = of_find_node_by_type(np, "cpu")) {
 708                 ireg = (u32 *)get_property(np, "reg", &ilen);
 709                 if (ireg && ireg[0] == get_hard_smp_processor_id(boot_cpuid)) {
 710                         ireg = (u32 *)get_property(np,
 711                                                   "ibm,ppc-interrupt-gserver#s",
 712                                                    &ilen);
 713                         i = ilen / sizeof(int);
 714                         if (ireg && i > 0) {
 715                                 default_server = ireg[0];
 716                                 /* take last element */
 717                                 default_distrib_server = ireg[i-1];
 718                         }
 719                         ireg = (u32 *)get_property(np,
 720                                         "ibm,interrupt-server#-size", NULL);
 721                         if (ireg)
 722                                 interrupt_server_size = *ireg;
 723                         break;
 724                 }
 725         }
 726         of_node_put(np);
 727
 728         if (firmware_has_feature(FW_FEATURE_LPAR))
 729                 ppc_md.get_irq = xics_get_irq_lpar;
 730         else
 731                 ppc_md.get_irq = xics_get_irq_direct;
 732
 733         xics_setup_cpu();
 734
 735         xics_setup_8259_cascade();
 736
 737         ppc64_boot_msg(0x21, "XICS Done");
 738 }
 739
 740
 741 #ifdef CONFIG_SMP
 742 void xics_request_IPIs(void)
 743 {
 744         unsigned int ipi;
 745
 746         ipi = irq_create_mapping(xics_host, XICS_IPI);
 747         BUG_ON(ipi == NO_IRQ);
 748
 749         /*
 750          * IPIs are marked IRQF_DISABLED as they must run with irqs
 751          * disabled
 752          */
 753         set_irq_handler(ipi, handle_percpu_irq);
 754         if (firmware_has_feature(FW_FEATURE_LPAR))
 755                 request_irq(ipi, xics_ipi_action_lpar, IRQF_DISABLED,
 756                             "IPI", NULL);
 757         else
 758                 request_irq(ipi, xics_ipi_action_direct, IRQF_DISABLED,
 759                             "IPI", NULL);
 760 }
 761 #endif /* CONFIG_SMP */
 762
 763 void xics_teardown_cpu(int secondary)
 764 {
 765         int cpu = smp_processor_id();
 766         unsigned int ipi;
 767         struct irq_desc *desc;
 768
 769         xics_set_cpu_priority(cpu, 0);
 770
 771         /*
 772          * Clear IPI
 773          */
 774         if (firmware_has_feature(FW_FEATURE_LPAR))
 775                 lpar_qirr_info(cpu, 0xff);
 776         else
 777                 direct_qirr_info(cpu, 0xff);
 778
 779         /*
 780          * we need to EOI the IPI if we got here from kexec down IPI
 781          *
 782          * probably need to check all the other interrupts too
 783          * should we be flagging idle loop instead?
 784          * or creating some task to be scheduled?
 785          */
 786
 787         ipi = irq_find_mapping(xics_host, XICS_IPI);
 788         if (ipi == XICS_IRQ_SPURIOUS)
 789                 return;
 790         desc = get_irq_desc(ipi);
 791         if (desc->chip && desc->chip->eoi)
 792                 desc->chip->eoi(ipi);
 793
 794         /*
 795          * Some machines need to have at least one cpu in the GIQ,
 796          * so leave the master cpu in the group.
 797          */
 798         if (secondary)
 799                 rtas_set_indicator(GLOBAL_INTERRUPT_QUEUE,
 800                                    (1UL << interrupt_server_size) - 1 -
 801                                    default_distrib_server, 0);
 802 }
 803
 804 #ifdef CONFIG_HOTPLUG_CPU
 805
 806 /* Interrupts are disabled. */
 807 void xics_migrate_irqs_away(void)
 808 {
 809         int status;
 810         unsigned int irq, virq, cpu = smp_processor_id();
 811
 812         /* Reject any interrupt that was queued to us... */
 813         xics_set_cpu_priority(cpu, 0);
 814
 815         /* remove ourselves from the global interrupt queue */
 816         status = rtas_set_indicator(GLOBAL_INTERRUPT_QUEUE,
 817                 (1UL << interrupt_server_size) - 1 - default_distrib_server, 0);
 818         WARN_ON(status < 0);
 819
 820         /* Allow IPIs again... */
 821         xics_set_cpu_priority(cpu, DEFAULT_PRIORITY);
 822
 823         for_each_irq(virq) {
 824                 struct irq_desc *desc;
 825                 int xics_status[2];
 826                 unsigned long flags;
 827
 828                 /* We cant set affinity on ISA interrupts */
 829                 if (virq < NUM_ISA_INTERRUPTS)
 830                         continue;
 831                 if (irq_map[virq].host != xics_host)
 832                         continue;
 833                 irq = (unsigned int)irq_map[virq].hwirq;
 834                 /* We need to get IPIs still. */
 835                 if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
 836                         continue;
 837                 desc = get_irq_desc(virq);
 838
 839                 /* We only need to migrate enabled IRQS */
 840                 if (desc == NULL || desc->chip == NULL
 841                     || desc->action == NULL
 842                     || desc->chip->set_affinity == NULL)
 843                         continue;
 844
 845                 spin_lock_irqsave(&desc->lock, flags);
 846
 847                 status = rtas_call(ibm_get_xive, 1, 3, xics_status, irq);
 848                 if (status) {
 849                         printk(KERN_ERR "migrate_irqs_away: irq=%u "
 850                                         "ibm,get-xive returns %d\n",
 851                                         virq, status);
 852                         goto unlock;
 853                 }
 854
 855                 /*
 856                  * We only support delivery to all cpus or to one cpu.
 857                  * The irq has to be migrated only in the single cpu
 858                  * case.
 859                  */
 860                 if (xics_status[0] != get_hard_smp_processor_id(cpu))
 861                         goto unlock;
 862
 863                 printk(KERN_WARNING "IRQ %u affinity broken off cpu %u\n",
 864                        virq, cpu);
 865
 866                 /* Reset affinity to all cpus */
 867                 desc->chip->set_affinity(virq, CPU_MASK_ALL);
 868                 irq_desc[irq].affinity = CPU_MASK_ALL;
 869 unlock:
 870                 spin_unlock_irqrestore(&desc->lock, flags);
 871         }
 872 }
 873 #endif