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 #include <linux/config.h>
  12 #include <linux/types.h>
  13 #include <linux/threads.h>
  14 #include <linux/kernel.h>
  15 #include <linux/irq.h>
  16 #include <linux/smp.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/signal.h>
  19 #include <linux/init.h>
  20 #include <linux/gfp.h>
  21 #include <linux/radix-tree.h>
  22 #include <linux/cpu.h>
  23 #include <asm/firmware.h>
  24 #include <asm/prom.h>
  25 #include <asm/io.h>
  26 #include <asm/pgtable.h>
  27 #include <asm/smp.h>
  28 #include <asm/rtas.h>
  29 #include <asm/hvcall.h>
  30 #include <asm/machdep.h>
  31 #include <asm/i8259.h>
  32
  33 #include "xics.h"
  34
  35 static unsigned int xics_startup(unsigned int irq);
  36 static void xics_enable_irq(unsigned int irq);
  37 static void xics_disable_irq(unsigned int irq);
  38 static void xics_mask_and_ack_irq(unsigned int irq);
  39 static void xics_end_irq(unsigned int irq);
  40 static void xics_set_affinity(unsigned int irq_nr, cpumask_t cpumask);
  41
  42 static struct hw_interrupt_type xics_pic = {
  43         .typename = " XICS     ",
  44         .startup = xics_startup,
  45         .enable = xics_enable_irq,
  46         .disable = xics_disable_irq,
  47         .ack = xics_mask_and_ack_irq,
  48         .end = xics_end_irq,
  49         .set_affinity = xics_set_affinity
  50 };
  51
  52 /* This is used to map real irq numbers to virtual */
  53 static struct radix_tree_root irq_map = RADIX_TREE_INIT(GFP_ATOMIC);
  54
  55 #define XICS_IPI                2
  56 #define XICS_IRQ_SPURIOUS       0
  57
  58 /* Want a priority other than 0.  Various HW issues require this. */
  59 #define DEFAULT_PRIORITY        5
  60
  61 /*
  62  * Mark IPIs as higher priority so we can take them inside interrupts that
  63  * arent marked SA_INTERRUPT
  64  */
  65 #define IPI_PRIORITY            4
  66
  67 struct xics_ipl {
  68         union {
  69                 u32 word;
  70                 u8 bytes[4];
  71         } xirr_poll;
  72         union {
  73                 u32 word;
  74                 u8 bytes[4];
  75         } xirr;
  76         u32 dummy;
  77         union {
  78                 u32 word;
  79                 u8 bytes[4];
  80         } qirr;
  81 };
  82
  83 static struct xics_ipl __iomem *xics_per_cpu[NR_CPUS];
  84
  85 static int xics_irq_8259_cascade = 0;
  86 static int xics_irq_8259_cascade_real = 0;
  87 static unsigned int default_server = 0xFF;
  88 static unsigned int default_distrib_server = 0;
  89 static unsigned int interrupt_server_size = 8;
  90
  91 /*
  92  * XICS only has a single IPI, so encode the messages per CPU
  93  */
  94 struct xics_ipi_struct xics_ipi_message[NR_CPUS] __cacheline_aligned;
  95
  96 /* RTAS service tokens */
  97 static int ibm_get_xive;
  98 static int ibm_set_xive;
  99 static int ibm_int_on;
 100 static int ibm_int_off;
 101
 102 typedef struct {
 103         int (*xirr_info_get)(int cpu);
 104         void (*xirr_info_set)(int cpu, int val);
 105         void (*cppr_info)(int cpu, u8 val);
 106         void (*qirr_info)(int cpu, u8 val);
 107 } xics_ops;
 108
 109
 110 /* SMP */
 111
 112 static int pSeries_xirr_info_get(int n_cpu)
 113 {
 114         return in_be32(&xics_per_cpu[n_cpu]->xirr.word);
 115 }
 116
 117 static void pSeries_xirr_info_set(int n_cpu, int value)
 118 {
 119         out_be32(&xics_per_cpu[n_cpu]->xirr.word, value);
 120 }
 121
 122 static void pSeries_cppr_info(int n_cpu, u8 value)
 123 {
 124         out_8(&xics_per_cpu[n_cpu]->xirr.bytes[0], value);
 125 }
 126
 127 static void pSeries_qirr_info(int n_cpu, u8 value)
 128 {
 129         out_8(&xics_per_cpu[n_cpu]->qirr.bytes[0], value);
 130 }
 131
 132 static xics_ops pSeries_ops = {
 133         pSeries_xirr_info_get,
 134         pSeries_xirr_info_set,
 135         pSeries_cppr_info,
 136         pSeries_qirr_info
 137 };
 138
 139 static xics_ops *ops = &pSeries_ops;
 140
 141
 142 /* LPAR */
 143
 144 static inline long plpar_eoi(unsigned long xirr)
 145 {
 146         return plpar_hcall_norets(H_EOI, xirr);
 147 }
 148
 149 static inline long plpar_cppr(unsigned long cppr)
 150 {
 151         return plpar_hcall_norets(H_CPPR, cppr);
 152 }
 153
 154 static inline long plpar_ipi(unsigned long servernum, unsigned long mfrr)
 155 {
 156         return plpar_hcall_norets(H_IPI, servernum, mfrr);
 157 }
 158
 159 static inline long plpar_xirr(unsigned long *xirr_ret)
 160 {
 161         unsigned long dummy;
 162         return plpar_hcall(H_XIRR, 0, 0, 0, 0, xirr_ret, &dummy, &dummy);
 163 }
 164
 165 static int pSeriesLP_xirr_info_get(int n_cpu)
 166 {
 167         unsigned long lpar_rc;
 168         unsigned long return_value;
 169
 170         lpar_rc = plpar_xirr(&return_value);
 171         if (lpar_rc != H_SUCCESS)
 172                 panic(" bad return code xirr - rc = %lx \n", lpar_rc);
 173         return (int)return_value;
 174 }
 175
 176 static void pSeriesLP_xirr_info_set(int n_cpu, int value)
 177 {
 178         unsigned long lpar_rc;
 179         unsigned long val64 = value & 0xffffffff;
 180
 181         lpar_rc = plpar_eoi(val64);
 182         if (lpar_rc != H_SUCCESS)
 183                 panic("bad return code EOI - rc = %ld, value=%lx\n", lpar_rc,
 184                       val64);
 185 }
 186
 187 void pSeriesLP_cppr_info(int n_cpu, u8 value)
 188 {
 189         unsigned long lpar_rc;
 190
 191         lpar_rc = plpar_cppr(value);
 192         if (lpar_rc != H_SUCCESS)
 193                 panic("bad return code cppr - rc = %lx\n", lpar_rc);
 194 }
 195
 196 static void pSeriesLP_qirr_info(int n_cpu , u8 value)
 197 {
 198         unsigned long lpar_rc;
 199
 200         lpar_rc = plpar_ipi(get_hard_smp_processor_id(n_cpu), value);
 201         if (lpar_rc != H_SUCCESS)
 202                 panic("bad return code qirr - rc = %lx\n", lpar_rc);
 203 }
 204
 205 xics_ops pSeriesLP_ops = {
 206         pSeriesLP_xirr_info_get,
 207         pSeriesLP_xirr_info_set,
 208         pSeriesLP_cppr_info,
 209         pSeriesLP_qirr_info
 210 };
 211
 212 static unsigned int xics_startup(unsigned int virq)
 213 {
 214         unsigned int irq;
 215
 216         irq = irq_offset_down(virq);
 217         if (radix_tree_insert(&irq_map, virt_irq_to_real(irq),
 218                               &virt_irq_to_real_map[irq]) == -ENOMEM)
 219                 printk(KERN_CRIT "Out of memory creating real -> virtual"
 220                        " IRQ mapping for irq %u (real 0x%x)\n",
 221                        virq, virt_irq_to_real(irq));
 222         xics_enable_irq(virq);
 223         return 0;       /* return value is ignored */
 224 }
 225
 226 static unsigned int real_irq_to_virt(unsigned int real_irq)
 227 {
 228         unsigned int *ptr;
 229
 230         ptr = radix_tree_lookup(&irq_map, real_irq);
 231         if (ptr == NULL)
 232                 return NO_IRQ;
 233         return ptr - virt_irq_to_real_map;
 234 }
 235
 236 #ifdef CONFIG_SMP
 237 static int get_irq_server(unsigned int irq)
 238 {
 239         unsigned int server;
 240         /* For the moment only implement delivery to all cpus or one cpu */
 241         cpumask_t cpumask = irq_affinity[irq];
 242         cpumask_t tmp = CPU_MASK_NONE;
 243
 244         if (!distribute_irqs)
 245                 return default_server;
 246
 247         if (cpus_equal(cpumask, CPU_MASK_ALL)) {
 248                 server = default_distrib_server;
 249         } else {
 250                 cpus_and(tmp, cpu_online_map, cpumask);
 251
 252                 if (cpus_empty(tmp))
 253                         server = default_distrib_server;
 254                 else
 255                         server = get_hard_smp_processor_id(first_cpu(tmp));
 256         }
 257
 258         return server;
 259
 260 }
 261 #else
 262 static int get_irq_server(unsigned int irq)
 263 {
 264         return default_server;
 265 }
 266 #endif
 267
 268 static void xics_enable_irq(unsigned int virq)
 269 {
 270         unsigned int irq;
 271         int call_status;
 272         unsigned int server;
 273
 274         irq = virt_irq_to_real(irq_offset_down(virq));
 275         if (irq == XICS_IPI)
 276                 return;
 277
 278         server = get_irq_server(virq);
 279         call_status = rtas_call(ibm_set_xive, 3, 1, NULL, irq, server,
 280                                 DEFAULT_PRIORITY);
 281         if (call_status != 0) {
 282                 printk(KERN_ERR "xics_enable_irq: irq=%u: ibm_set_xive "
 283                        "returned %d\n", irq, call_status);
 284                 printk("set_xive %x, server %x\n", ibm_set_xive, server);
 285                 return;
 286         }
 287
 288         /* Now unmask the interrupt (often a no-op) */
 289         call_status = rtas_call(ibm_int_on, 1, 1, NULL, irq);
 290         if (call_status != 0) {
 291                 printk(KERN_ERR "xics_enable_irq: irq=%u: ibm_int_on "
 292                        "returned %d\n", irq, call_status);
 293                 return;
 294         }
 295 }
 296
 297 static void xics_disable_real_irq(unsigned int irq)
 298 {
 299         int call_status;
 300         unsigned int server;
 301
 302         if (irq == XICS_IPI)
 303                 return;
 304
 305         call_status = rtas_call(ibm_int_off, 1, 1, NULL, irq);
 306         if (call_status != 0) {
 307                 printk(KERN_ERR "xics_disable_real_irq: irq=%u: "
 308                        "ibm_int_off returned %d\n", irq, call_status);
 309                 return;
 310         }
 311
 312         server = get_irq_server(irq);
 313         /* Have to set XIVE to 0xff to be able to remove a slot */
 314         call_status = rtas_call(ibm_set_xive, 3, 1, NULL, irq, server, 0xff);
 315         if (call_status != 0) {
 316                 printk(KERN_ERR "xics_disable_irq: irq=%u: ibm_set_xive(0xff)"
 317                        " returned %d\n", irq, call_status);
 318                 return;
 319         }
 320 }
 321
 322 static void xics_disable_irq(unsigned int virq)
 323 {
 324         unsigned int irq;
 325
 326         irq = virt_irq_to_real(irq_offset_down(virq));
 327         xics_disable_real_irq(irq);
 328 }
 329
 330 static void xics_end_irq(unsigned int irq)
 331 {
 332         int cpu = smp_processor_id();
 333
 334         iosync();
 335         ops->xirr_info_set(cpu, ((0xff << 24) |
 336                                  (virt_irq_to_real(irq_offset_down(irq)))));
 337
 338 }
 339
 340 static void xics_mask_and_ack_irq(unsigned int irq)
 341 {
 342         int cpu = smp_processor_id();
 343
 344         if (irq < irq_offset_value()) {
 345                 i8259_pic.ack(irq);
 346                 iosync();
 347                 ops->xirr_info_set(cpu, ((0xff<<24) |
 348                                          xics_irq_8259_cascade_real));
 349                 iosync();
 350         }
 351 }
 352
 353 int xics_get_irq(struct pt_regs *regs)
 354 {
 355         unsigned int cpu = smp_processor_id();
 356         unsigned int vec;
 357         int irq;
 358
 359         vec = ops->xirr_info_get(cpu);
 360         /*  (vec >> 24) == old priority */
 361         vec &= 0x00ffffff;
 362
 363         /* for sanity, this had better be < NR_IRQS - 16 */
 364         if (vec == xics_irq_8259_cascade_real) {
 365                 irq = i8259_irq(regs);
 366                 xics_end_irq(irq_offset_up(xics_irq_8259_cascade));
 367         } else if (vec == XICS_IRQ_SPURIOUS) {
 368                 irq = -1;
 369         } else {
 370                 irq = real_irq_to_virt(vec);
 371                 if (irq == NO_IRQ)
 372                         irq = real_irq_to_virt_slowpath(vec);
 373                 if (irq == NO_IRQ) {
 374                         printk(KERN_ERR "Interrupt %u (real) is invalid,"
 375                                " disabling it.\n", vec);
 376                         xics_disable_real_irq(vec);
 377                 } else
 378                         irq = irq_offset_up(irq);
 379         }
 380         return irq;
 381 }
 382
 383 #ifdef CONFIG_SMP
 384
 385 static irqreturn_t xics_ipi_action(int irq, void *dev_id, struct pt_regs *regs)
 386 {
 387         int cpu = smp_processor_id();
 388
 389         ops->qirr_info(cpu, 0xff);
 390
 391         WARN_ON(cpu_is_offline(cpu));
 392
 393         while (xics_ipi_message[cpu].value) {
 394                 if (test_and_clear_bit(PPC_MSG_CALL_FUNCTION,
 395                                        &xics_ipi_message[cpu].value)) {
 396                         mb();
 397                         smp_message_recv(PPC_MSG_CALL_FUNCTION, regs);
 398                 }
 399                 if (test_and_clear_bit(PPC_MSG_RESCHEDULE,
 400                                        &xics_ipi_message[cpu].value)) {
 401                         mb();
 402                         smp_message_recv(PPC_MSG_RESCHEDULE, regs);
 403                 }
 404 #if 0
 405                 if (test_and_clear_bit(PPC_MSG_MIGRATE_TASK,
 406                                        &xics_ipi_message[cpu].value)) {
 407                         mb();
 408                         smp_message_recv(PPC_MSG_MIGRATE_TASK, regs);
 409                 }
 410 #endif
 411 #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
 412                 if (test_and_clear_bit(PPC_MSG_DEBUGGER_BREAK,
 413                                        &xics_ipi_message[cpu].value)) {
 414                         mb();
 415                         smp_message_recv(PPC_MSG_DEBUGGER_BREAK, regs);
 416                 }
 417 #endif
 418         }
 419         return IRQ_HANDLED;
 420 }
 421
 422 void xics_cause_IPI(int cpu)
 423 {
 424         ops->qirr_info(cpu, IPI_PRIORITY);
 425 }
 426 #endif /* CONFIG_SMP */
 427
 428 void xics_setup_cpu(void)
 429 {
 430         int cpu = smp_processor_id();
 431
 432         ops->cppr_info(cpu, 0xff);
 433         iosync();
 434
 435         /*
 436          * Put the calling processor into the GIQ.  This is really only
 437          * necessary from a secondary thread as the OF start-cpu interface
 438          * performs this function for us on primary threads.
 439          *
 440          * XXX: undo of teardown on kexec needs this too, as may hotplug
 441          */
 442         rtas_set_indicator(GLOBAL_INTERRUPT_QUEUE,
 443                 (1UL << interrupt_server_size) - 1 - default_distrib_server, 1);
 444 }
 445
 446 void xics_init_IRQ(void)
 447 {
 448         int i;
 449         unsigned long intr_size = 0;
 450         struct device_node *np;
 451         uint *ireg, ilen, indx = 0;
 452         unsigned long intr_base = 0;
 453         struct xics_interrupt_node {
 454                 unsigned long addr;
 455                 unsigned long size;
 456         } intnodes[NR_CPUS];
 457
 458         ppc64_boot_msg(0x20, "XICS Init");
 459
 460         ibm_get_xive = rtas_token("ibm,get-xive");
 461         ibm_set_xive = rtas_token("ibm,set-xive");
 462         ibm_int_on  = rtas_token("ibm,int-on");
 463         ibm_int_off = rtas_token("ibm,int-off");
 464
 465         np = of_find_node_by_type(NULL, "PowerPC-External-Interrupt-Presentation");
 466         if (!np)
 467                 panic("xics_init_IRQ: can't find interrupt presentation");
 468
 469 nextnode:
 470         ireg = (uint *)get_property(np, "ibm,interrupt-server-ranges", NULL);
 471         if (ireg) {
 472                 /*
 473                  * set node starting index for this node
 474                  */
 475                 indx = *ireg;
 476         }
 477
 478         ireg = (uint *)get_property(np, "reg", &ilen);
 479         if (!ireg)
 480                 panic("xics_init_IRQ: can't find interrupt reg property");
 481
 482         while (ilen) {
 483                 intnodes[indx].addr = (unsigned long)*ireg++ << 32;
 484                 ilen -= sizeof(uint);
 485                 intnodes[indx].addr |= *ireg++;
 486                 ilen -= sizeof(uint);
 487                 intnodes[indx].size = (unsigned long)*ireg++ << 32;
 488                 ilen -= sizeof(uint);
 489                 intnodes[indx].size |= *ireg++;
 490                 ilen -= sizeof(uint);
 491                 indx++;
 492                 if (indx >= NR_CPUS) break;
 493         }
 494
 495         np = of_find_node_by_type(np, "PowerPC-External-Interrupt-Presentation");
 496         if ((indx < NR_CPUS) && np) goto nextnode;
 497
 498         /* Find the server numbers for the boot cpu. */
 499         for (np = of_find_node_by_type(NULL, "cpu");
 500              np;
 501              np = of_find_node_by_type(np, "cpu")) {
 502                 ireg = (uint *)get_property(np, "reg", &ilen);
 503                 if (ireg && ireg[0] == get_hard_smp_processor_id(boot_cpuid)) {
 504                         ireg = (uint *)get_property(np, "ibm,ppc-interrupt-gserver#s",
 505                                                     &ilen);
 506                         i = ilen / sizeof(int);
 507                         if (ireg && i > 0) {
 508                                 default_server = ireg[0];
 509                                 default_distrib_server = ireg[i-1]; /* take last element */
 510                         }
 511                         ireg = (uint *)get_property(np,
 512                                         "ibm,interrupt-server#-size", NULL);
 513                         if (ireg)
 514                                 interrupt_server_size = *ireg;
 515                         break;
 516                 }
 517         }
 518         of_node_put(np);
 519
 520         intr_base = intnodes[0].addr;
 521         intr_size = intnodes[0].size;
 522
 523         np = of_find_node_by_type(NULL, "interrupt-controller");
 524         if (!np) {
 525                 printk(KERN_WARNING "xics: no ISA interrupt controller\n");
 526                 xics_irq_8259_cascade_real = -1;
 527                 xics_irq_8259_cascade = -1;
 528         } else {
 529                 ireg = (uint *) get_property(np, "interrupts", NULL);
 530                 if (!ireg)
 531                         panic("xics_init_IRQ: can't find ISA interrupts property");
 532
 533                 xics_irq_8259_cascade_real = *ireg;
 534                 xics_irq_8259_cascade
 535                         = virt_irq_create_mapping(xics_irq_8259_cascade_real);
 536                 i8259_init(0, 0);
 537                 of_node_put(np);
 538         }
 539
 540         if (firmware_has_feature(FW_FEATURE_LPAR))
 541                 ops = &pSeriesLP_ops;
 542         else {
 543 #ifdef CONFIG_SMP
 544                 for_each_possible_cpu(i) {
 545                         int hard_id;
 546
 547                         /* FIXME: Do this dynamically! --RR */
 548                         if (!cpu_present(i))
 549                                 continue;
 550
 551                         hard_id = get_hard_smp_processor_id(i);
 552                         xics_per_cpu[i] = ioremap(intnodes[hard_id].addr,
 553                                                   intnodes[hard_id].size);
 554                 }
 555 #else
 556                 xics_per_cpu[0] = ioremap(intr_base, intr_size);
 557 #endif /* CONFIG_SMP */
 558         }
 559
 560         for (i = irq_offset_value(); i < NR_IRQS; ++i)
 561                 get_irq_desc(i)->handler = &xics_pic;
 562
 563         xics_setup_cpu();
 564
 565         ppc64_boot_msg(0x21, "XICS Done");
 566 }
 567
 568 /*
 569  * We cant do this in init_IRQ because we need the memory subsystem up for
 570  * request_irq()
 571  */
 572 static int __init xics_setup_i8259(void)
 573 {
 574         if (ppc64_interrupt_controller == IC_PPC_XIC &&
 575             xics_irq_8259_cascade != -1) {
 576                 if (request_irq(irq_offset_up(xics_irq_8259_cascade),
 577                                 no_action, 0, "8259 cascade", NULL))
 578                         printk(KERN_ERR "xics_setup_i8259: couldn't get 8259 "
 579                                         "cascade\n");
 580         }
 581         return 0;
 582 }
 583 arch_initcall(xics_setup_i8259);
 584
 585 #ifdef CONFIG_SMP
 586 void xics_request_IPIs(void)
 587 {
 588         virt_irq_to_real_map[XICS_IPI] = XICS_IPI;
 589
 590         /* IPIs are marked SA_INTERRUPT as they must run with irqs disabled */
 591         request_irq(irq_offset_up(XICS_IPI), xics_ipi_action, SA_INTERRUPT,
 592                     "IPI", NULL);
 593         get_irq_desc(irq_offset_up(XICS_IPI))->status |= IRQ_PER_CPU;
 594 }
 595 #endif
 596
 597 static void xics_set_affinity(unsigned int virq, cpumask_t cpumask)
 598 {
 599         unsigned int irq;
 600         int status;
 601         int xics_status[2];
 602         unsigned long newmask;
 603         cpumask_t tmp = CPU_MASK_NONE;
 604
 605         irq = virt_irq_to_real(irq_offset_down(virq));
 606         if (irq == XICS_IPI || irq == NO_IRQ)
 607                 return;
 608
 609         status = rtas_call(ibm_get_xive, 1, 3, xics_status, irq);
 610
 611         if (status) {
 612                 printk(KERN_ERR "xics_set_affinity: irq=%u ibm,get-xive "
 613                        "returns %d\n", irq, status);
 614                 return;
 615         }
 616
 617         /* For the moment only implement delivery to all cpus or one cpu */
 618         if (cpus_equal(cpumask, CPU_MASK_ALL)) {
 619                 newmask = default_distrib_server;
 620         } else {
 621                 cpus_and(tmp, cpu_online_map, cpumask);
 622                 if (cpus_empty(tmp))
 623                         return;
 624                 newmask = get_hard_smp_processor_id(first_cpu(tmp));
 625         }
 626
 627         status = rtas_call(ibm_set_xive, 3, 1, NULL,
 628                                 irq, newmask, xics_status[1]);
 629
 630         if (status) {
 631                 printk(KERN_ERR "xics_set_affinity: irq=%u ibm,set-xive "
 632                        "returns %d\n", irq, status);
 633                 return;
 634         }
 635 }
 636
 637 void xics_teardown_cpu(int secondary)
 638 {
 639         int cpu = smp_processor_id();
 640
 641         ops->cppr_info(cpu, 0x00);
 642         iosync();
 643
 644         /*
 645          * Some machines need to have at least one cpu in the GIQ,
 646          * so leave the master cpu in the group.
 647          */
 648         if (secondary) {
 649                 /*
 650                  * we need to EOI the IPI if we got here from kexec down IPI
 651                  *
 652                  * probably need to check all the other interrupts too
 653                  * should we be flagging idle loop instead?
 654                  * or creating some task to be scheduled?
 655                  */
 656                 ops->xirr_info_set(cpu, XICS_IPI);
 657                 rtas_set_indicator(GLOBAL_INTERRUPT_QUEUE,
 658                         (1UL << interrupt_server_size) - 1 -
 659                         default_distrib_server, 0);
 660         }
 661 }
 662
 663 #ifdef CONFIG_HOTPLUG_CPU
 664
 665 /* Interrupts are disabled. */
 666 void xics_migrate_irqs_away(void)
 667 {
 668         int status;
 669         unsigned int irq, virq, cpu = smp_processor_id();
 670
 671         /* Reject any interrupt that was queued to us... */
 672         ops->cppr_info(cpu, 0);
 673         iosync();
 674
 675         /* remove ourselves from the global interrupt queue */
 676         status = rtas_set_indicator(GLOBAL_INTERRUPT_QUEUE,
 677                 (1UL << interrupt_server_size) - 1 - default_distrib_server, 0);
 678         WARN_ON(status < 0);
 679
 680         /* Allow IPIs again... */
 681         ops->cppr_info(cpu, DEFAULT_PRIORITY);
 682         iosync();
 683
 684         for_each_irq(virq) {
 685                 irq_desc_t *desc;
 686                 int xics_status[2];
 687                 unsigned long flags;
 688
 689                 /* We cant set affinity on ISA interrupts */
 690                 if (virq < irq_offset_value())
 691                         continue;
 692
 693                 desc = get_irq_desc(virq);
 694                 irq = virt_irq_to_real(irq_offset_down(virq));
 695
 696                 /* We need to get IPIs still. */
 697                 if (irq == XICS_IPI || irq == NO_IRQ)
 698                         continue;
 699
 700                 /* We only need to migrate enabled IRQS */
 701                 if (desc == NULL || desc->handler == NULL
 702                     || desc->action == NULL
 703                     || desc->handler->set_affinity == NULL)
 704                         continue;
 705
 706                 spin_lock_irqsave(&desc->lock, flags);
 707
 708                 status = rtas_call(ibm_get_xive, 1, 3, xics_status, irq);
 709                 if (status) {
 710                         printk(KERN_ERR "migrate_irqs_away: irq=%u "
 711                                         "ibm,get-xive returns %d\n",
 712                                         virq, status);
 713                         goto unlock;
 714                 }
 715
 716                 /*
 717                  * We only support delivery to all cpus or to one cpu.
 718                  * The irq has to be migrated only in the single cpu
 719                  * case.
 720                  */
 721                 if (xics_status[0] != get_hard_smp_processor_id(cpu))
 722                         goto unlock;
 723
 724                 printk(KERN_WARNING "IRQ %u affinity broken off cpu %u\n",
 725                        virq, cpu);
 726
 727                 /* Reset affinity to all cpus */
 728                 desc->handler->set_affinity(virq, CPU_MASK_ALL);
 729                 irq_affinity[virq] = CPU_MASK_ALL;
 730 unlock:
 731                 spin_unlock_irqrestore(&desc->lock, flags);
 732         }
 733 }
 734 #endif