git.oblomov.eu Git - linux-2.6/blob - arch/powerpc/platforms/powermac/smp.c

   1 /*
   2  * SMP support for power macintosh.
   3  *
   4  * We support both the old "powersurge" SMP architecture
   5  * and the current Core99 (G4 PowerMac) machines.
   6  *
   7  * Note that we don't support the very first rev. of
   8  * Apple/DayStar 2 CPUs board, the one with the funky
   9  * watchdog. Hopefully, none of these should be there except
  10  * maybe internally to Apple. I should probably still add some
  11  * code to detect this card though and disable SMP. --BenH.
  12  *
  13  * Support Macintosh G4 SMP by Troy Benjegerdes (hozer@drgw.net)
  14  * and Ben Herrenschmidt <benh@kernel.crashing.org>.
  15  *
  16  * Support for DayStar quad CPU cards
  17  * Copyright (C) XLR8, Inc. 1994-2000
  18  *
  19  *  This program is free software; you can redistribute it and/or
  20  *  modify it under the terms of the GNU General Public License
  21  *  as published by the Free Software Foundation; either version
  22  *  2 of the License, or (at your option) any later version.
  23  */
  24 #include <linux/kernel.h>
  25 #include <linux/sched.h>
  26 #include <linux/smp.h>
  27 #include <linux/smp_lock.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/kernel_stat.h>
  30 #include <linux/delay.h>
  31 #include <linux/init.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/errno.h>
  34 #include <linux/hardirq.h>
  35 #include <linux/cpu.h>
  36 #include <linux/compiler.h>
  37
  38 #include <asm/ptrace.h>
  39 #include <asm/atomic.h>
  40 #include <asm/irq.h>
  41 #include <asm/page.h>
  42 #include <asm/pgtable.h>
  43 #include <asm/sections.h>
  44 #include <asm/io.h>
  45 #include <asm/prom.h>
  46 #include <asm/smp.h>
  47 #include <asm/machdep.h>
  48 #include <asm/pmac_feature.h>
  49 #include <asm/time.h>
  50 #include <asm/mpic.h>
  51 #include <asm/cacheflush.h>
  52 #include <asm/keylargo.h>
  53 #include <asm/pmac_low_i2c.h>
  54 #include <asm/pmac_pfunc.h>
  55
  56 #define DEBUG
  57
  58 #ifdef DEBUG
  59 #define DBG(fmt...) udbg_printf(fmt)
  60 #else
  61 #define DBG(fmt...)
  62 #endif
  63
  64 extern void __secondary_start_pmac_0(void);
  65 extern int pmac_pfunc_base_install(void);
  66
  67 #ifdef CONFIG_PPC32
  68
  69 /* Sync flag for HW tb sync */
  70 static volatile int sec_tb_reset = 0;
  71
  72 /*
  73  * Powersurge (old powermac SMP) support.
  74  */
  75
  76 /* Addresses for powersurge registers */
  77 #define HAMMERHEAD_BASE         0xf8000000
  78 #define HHEAD_CONFIG            0x90
  79 #define HHEAD_SEC_INTR          0xc0
  80
  81 /* register for interrupting the primary processor on the powersurge */
  82 /* N.B. this is actually the ethernet ROM! */
  83 #define PSURGE_PRI_INTR         0xf3019000
  84
  85 /* register for storing the start address for the secondary processor */
  86 /* N.B. this is the PCI config space address register for the 1st bridge */
  87 #define PSURGE_START            0xf2800000
  88
  89 /* Daystar/XLR8 4-CPU card */
  90 #define PSURGE_QUAD_REG_ADDR    0xf8800000
  91
  92 #define PSURGE_QUAD_IRQ_SET     0
  93 #define PSURGE_QUAD_IRQ_CLR     1
  94 #define PSURGE_QUAD_IRQ_PRIMARY 2
  95 #define PSURGE_QUAD_CKSTOP_CTL  3
  96 #define PSURGE_QUAD_PRIMARY_ARB 4
  97 #define PSURGE_QUAD_BOARD_ID    6
  98 #define PSURGE_QUAD_WHICH_CPU   7
  99 #define PSURGE_QUAD_CKSTOP_RDBK 8
 100 #define PSURGE_QUAD_RESET_CTL   11
 101
 102 #define PSURGE_QUAD_OUT(r, v)   (out_8(quad_base + ((r) << 4) + 4, (v)))
 103 #define PSURGE_QUAD_IN(r)       (in_8(quad_base + ((r) << 4) + 4) & 0x0f)
 104 #define PSURGE_QUAD_BIS(r, v)   (PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) | (v)))
 105 #define PSURGE_QUAD_BIC(r, v)   (PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) & ~(v)))
 106
 107 /* virtual addresses for the above */
 108 static volatile u8 __iomem *hhead_base;
 109 static volatile u8 __iomem *quad_base;
 110 static volatile u32 __iomem *psurge_pri_intr;
 111 static volatile u8 __iomem *psurge_sec_intr;
 112 static volatile u32 __iomem *psurge_start;
 113
 114 /* values for psurge_type */
 115 #define PSURGE_NONE             -1
 116 #define PSURGE_DUAL             0
 117 #define PSURGE_QUAD_OKEE        1
 118 #define PSURGE_QUAD_COTTON      2
 119 #define PSURGE_QUAD_ICEGRASS    3
 120
 121 /* what sort of powersurge board we have */
 122 static int psurge_type = PSURGE_NONE;
 123
 124 /*
 125  * Set and clear IPIs for powersurge.
 126  */
 127 static inline void psurge_set_ipi(int cpu)
 128 {
 129         if (psurge_type == PSURGE_NONE)
 130                 return;
 131         if (cpu == 0)
 132                 in_be32(psurge_pri_intr);
 133         else if (psurge_type == PSURGE_DUAL)
 134                 out_8(psurge_sec_intr, 0);
 135         else
 136                 PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_SET, 1 << cpu);
 137 }
 138
 139 static inline void psurge_clr_ipi(int cpu)
 140 {
 141         if (cpu > 0) {
 142                 switch(psurge_type) {
 143                 case PSURGE_DUAL:
 144                         out_8(psurge_sec_intr, ~0);
 145                 case PSURGE_NONE:
 146                         break;
 147                 default:
 148                         PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, 1 << cpu);
 149                 }
 150         }
 151 }
 152
 153 /*
 154  * On powersurge (old SMP powermac architecture) we don't have
 155  * separate IPIs for separate messages like openpic does.  Instead
 156  * we have a bitmap for each processor, where a 1 bit means that
 157  * the corresponding message is pending for that processor.
 158  * Ideally each cpu's entry would be in a different cache line.
 159  *  -- paulus.
 160  */
 161 static unsigned long psurge_smp_message[NR_CPUS];
 162
 163 void psurge_smp_message_recv(struct pt_regs *regs)
 164 {
 165         int cpu = smp_processor_id();
 166         int msg;
 167
 168         /* clear interrupt */
 169         psurge_clr_ipi(cpu);
 170
 171         if (num_online_cpus() < 2)
 172                 return;
 173
 174         /* make sure there is a message there */
 175         for (msg = 0; msg < 4; msg++)
 176                 if (test_and_clear_bit(msg, &psurge_smp_message[cpu]))
 177                         smp_message_recv(msg, regs);
 178 }
 179
 180 irqreturn_t psurge_primary_intr(int irq, void *d, struct pt_regs *regs)
 181 {
 182         psurge_smp_message_recv(regs);
 183         return IRQ_HANDLED;
 184 }
 185
 186 static void smp_psurge_message_pass(int target, int msg)
 187 {
 188         int i;
 189
 190         if (num_online_cpus() < 2)
 191                 return;
 192
 193         for_each_online_cpu(i) {
 194                 if (target == MSG_ALL
 195                     || (target == MSG_ALL_BUT_SELF && i != smp_processor_id())
 196                     || target == i) {
 197                         set_bit(msg, &psurge_smp_message[i]);
 198                         psurge_set_ipi(i);
 199                 }
 200         }
 201 }
 202
 203 /*
 204  * Determine a quad card presence. We read the board ID register, we
 205  * force the data bus to change to something else, and we read it again.
 206  * It it's stable, then the register probably exist (ugh !)
 207  */
 208 static int __init psurge_quad_probe(void)
 209 {
 210         int type;
 211         unsigned int i;
 212
 213         type = PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID);
 214         if (type < PSURGE_QUAD_OKEE || type > PSURGE_QUAD_ICEGRASS
 215             || type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
 216                 return PSURGE_DUAL;
 217
 218         /* looks OK, try a slightly more rigorous test */
 219         /* bogus is not necessarily cacheline-aligned,
 220            though I don't suppose that really matters.  -- paulus */
 221         for (i = 0; i < 100; i++) {
 222                 volatile u32 bogus[8];
 223                 bogus[(0+i)%8] = 0x00000000;
 224                 bogus[(1+i)%8] = 0x55555555;
 225                 bogus[(2+i)%8] = 0xFFFFFFFF;
 226                 bogus[(3+i)%8] = 0xAAAAAAAA;
 227                 bogus[(4+i)%8] = 0x33333333;
 228                 bogus[(5+i)%8] = 0xCCCCCCCC;
 229                 bogus[(6+i)%8] = 0xCCCCCCCC;
 230                 bogus[(7+i)%8] = 0x33333333;
 231                 wmb();
 232                 asm volatile("dcbf 0,%0" : : "r" (bogus) : "memory");
 233                 mb();
 234                 if (type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
 235                         return PSURGE_DUAL;
 236         }
 237         return type;
 238 }
 239
 240 static void __init psurge_quad_init(void)
 241 {
 242         int procbits;
 243
 244         if (ppc_md.progress) ppc_md.progress("psurge_quad_init", 0x351);
 245         procbits = ~PSURGE_QUAD_IN(PSURGE_QUAD_WHICH_CPU);
 246         if (psurge_type == PSURGE_QUAD_ICEGRASS)
 247                 PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
 248         else
 249                 PSURGE_QUAD_BIC(PSURGE_QUAD_CKSTOP_CTL, procbits);
 250         mdelay(33);
 251         out_8(psurge_sec_intr, ~0);
 252         PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, procbits);
 253         PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
 254         if (psurge_type != PSURGE_QUAD_ICEGRASS)
 255                 PSURGE_QUAD_BIS(PSURGE_QUAD_CKSTOP_CTL, procbits);
 256         PSURGE_QUAD_BIC(PSURGE_QUAD_PRIMARY_ARB, procbits);
 257         mdelay(33);
 258         PSURGE_QUAD_BIC(PSURGE_QUAD_RESET_CTL, procbits);
 259         mdelay(33);
 260         PSURGE_QUAD_BIS(PSURGE_QUAD_PRIMARY_ARB, procbits);
 261         mdelay(33);
 262 }
 263
 264 static int __init smp_psurge_probe(void)
 265 {
 266         int i, ncpus;
 267
 268         /* We don't do SMP on the PPC601 -- paulus */
 269         if (PVR_VER(mfspr(SPRN_PVR)) == 1)
 270                 return 1;
 271
 272         /*
 273          * The powersurge cpu board can be used in the generation
 274          * of powermacs that have a socket for an upgradeable cpu card,
 275          * including the 7500, 8500, 9500, 9600.
 276          * The device tree doesn't tell you if you have 2 cpus because
 277          * OF doesn't know anything about the 2nd processor.
 278          * Instead we look for magic bits in magic registers,
 279          * in the hammerhead memory controller in the case of the
 280          * dual-cpu powersurge board.  -- paulus.
 281          */
 282         if (find_devices("hammerhead") == NULL)
 283                 return 1;
 284
 285         hhead_base = ioremap(HAMMERHEAD_BASE, 0x800);
 286         quad_base = ioremap(PSURGE_QUAD_REG_ADDR, 1024);
 287         psurge_sec_intr = hhead_base + HHEAD_SEC_INTR;
 288
 289         psurge_type = psurge_quad_probe();
 290         if (psurge_type != PSURGE_DUAL) {
 291                 psurge_quad_init();
 292                 /* All released cards using this HW design have 4 CPUs */
 293                 ncpus = 4;
 294         } else {
 295                 iounmap(quad_base);
 296                 if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
 297                         /* not a dual-cpu card */
 298                         iounmap(hhead_base);
 299                         psurge_type = PSURGE_NONE;
 300                         return 1;
 301                 }
 302                 ncpus = 2;
 303         }
 304
 305         psurge_start = ioremap(PSURGE_START, 4);
 306         psurge_pri_intr = ioremap(PSURGE_PRI_INTR, 4);
 307
 308         /*
 309          * This is necessary because OF doesn't know about the
 310          * secondary cpu(s), and thus there aren't nodes in the
 311          * device tree for them, and smp_setup_cpu_maps hasn't
 312          * set their bits in cpu_possible_map and cpu_present_map.
 313          */
 314         if (ncpus > NR_CPUS)
 315                 ncpus = NR_CPUS;
 316         for (i = 1; i < ncpus ; ++i) {
 317                 cpu_set(i, cpu_present_map);
 318                 cpu_set(i, cpu_possible_map);
 319                 set_hard_smp_processor_id(i, i);
 320         }
 321
 322         if (ppc_md.progress) ppc_md.progress("smp_psurge_probe - done", 0x352);
 323
 324         return ncpus;
 325 }
 326
 327 static void __init smp_psurge_kick_cpu(int nr)
 328 {
 329         unsigned long start = __pa(__secondary_start_pmac_0) + nr * 8;
 330         unsigned long a;
 331
 332         /* may need to flush here if secondary bats aren't setup */
 333         for (a = KERNELBASE; a < KERNELBASE + 0x800000; a += 32)
 334                 asm volatile("dcbf 0,%0" : : "r" (a) : "memory");
 335         asm volatile("sync");
 336
 337         if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu", 0x353);
 338
 339         out_be32(psurge_start, start);
 340         mb();
 341
 342         psurge_set_ipi(nr);
 343         udelay(10);
 344         psurge_clr_ipi(nr);
 345
 346         if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
 347 }
 348
 349 /*
 350  * With the dual-cpu powersurge board, the decrementers and timebases
 351  * of both cpus are frozen after the secondary cpu is started up,
 352  * until we give the secondary cpu another interrupt.  This routine
 353  * uses this to get the timebases synchronized.
 354  *  -- paulus.
 355  */
 356 static void __init psurge_dual_sync_tb(int cpu_nr)
 357 {
 358         int t;
 359
 360         set_dec(tb_ticks_per_jiffy);
 361         /* XXX fixme */
 362         set_tb(0, 0);
 363
 364         if (cpu_nr > 0) {
 365                 mb();
 366                 sec_tb_reset = 1;
 367                 return;
 368         }
 369
 370         /* wait for the secondary to have reset its TB before proceeding */
 371         for (t = 10000000; t > 0 && !sec_tb_reset; --t)
 372                 ;
 373
 374         /* now interrupt the secondary, starting both TBs */
 375         psurge_set_ipi(1);
 376 }
 377
 378 static struct irqaction psurge_irqaction = {
 379         .handler = psurge_primary_intr,
 380         .flags = IRQF_DISABLED,
 381         .mask = CPU_MASK_NONE,
 382         .name = "primary IPI",
 383 };
 384
 385 static void __init smp_psurge_setup_cpu(int cpu_nr)
 386 {
 387
 388         if (cpu_nr == 0) {
 389                 /* If we failed to start the second CPU, we should still
 390                  * send it an IPI to start the timebase & DEC or we might
 391                  * have them stuck.
 392                  */
 393                 if (num_online_cpus() < 2) {
 394                         if (psurge_type == PSURGE_DUAL)
 395                                 psurge_set_ipi(1);
 396                         return;
 397                 }
 398                 /* reset the entry point so if we get another intr we won't
 399                  * try to startup again */
 400                 out_be32(psurge_start, 0x100);
 401                 if (setup_irq(30, &psurge_irqaction))
 402                         printk(KERN_ERR "Couldn't get primary IPI interrupt");
 403         }
 404
 405         if (psurge_type == PSURGE_DUAL)
 406                 psurge_dual_sync_tb(cpu_nr);
 407 }
 408
 409 void __init smp_psurge_take_timebase(void)
 410 {
 411         /* Dummy implementation */
 412 }
 413
 414 void __init smp_psurge_give_timebase(void)
 415 {
 416         /* Dummy implementation */
 417 }
 418
 419 /* PowerSurge-style Macs */
 420 struct smp_ops_t psurge_smp_ops = {
 421         .message_pass   = smp_psurge_message_pass,
 422         .probe          = smp_psurge_probe,
 423         .kick_cpu       = smp_psurge_kick_cpu,
 424         .setup_cpu      = smp_psurge_setup_cpu,
 425         .give_timebase  = smp_psurge_give_timebase,
 426         .take_timebase  = smp_psurge_take_timebase,
 427 };
 428 #endif /* CONFIG_PPC32 - actually powersurge support */
 429
 430 /*
 431  * Core 99 and later support
 432  */
 433
 434 static void (*pmac_tb_freeze)(int freeze);
 435 static u64 timebase;
 436 static int tb_req;
 437
 438 static void smp_core99_give_timebase(void)
 439 {
 440         unsigned long flags;
 441
 442         local_irq_save(flags);
 443
 444         while(!tb_req)
 445                 barrier();
 446         tb_req = 0;
 447         (*pmac_tb_freeze)(1);
 448         mb();
 449         timebase = get_tb();
 450         mb();
 451         while (timebase)
 452                 barrier();
 453         mb();
 454         (*pmac_tb_freeze)(0);
 455         mb();
 456
 457         local_irq_restore(flags);
 458 }
 459
 460
 461 static void __devinit smp_core99_take_timebase(void)
 462 {
 463         unsigned long flags;
 464
 465         local_irq_save(flags);
 466
 467         tb_req = 1;
 468         mb();
 469         while (!timebase)
 470                 barrier();
 471         mb();
 472         set_tb(timebase >> 32, timebase & 0xffffffff);
 473         timebase = 0;
 474         mb();
 475         set_dec(tb_ticks_per_jiffy/2);
 476
 477         local_irq_restore(flags);
 478 }
 479
 480 #ifdef CONFIG_PPC64
 481 /*
 482  * G5s enable/disable the timebase via an i2c-connected clock chip.
 483  */
 484 static struct pmac_i2c_bus *pmac_tb_clock_chip_host;
 485 static u8 pmac_tb_pulsar_addr;
 486
 487 static void smp_core99_cypress_tb_freeze(int freeze)
 488 {
 489         u8 data;
 490         int rc;
 491
 492         /* Strangely, the device-tree says address is 0xd2, but darwin
 493          * accesses 0xd0 ...
 494          */
 495         pmac_i2c_setmode(pmac_tb_clock_chip_host,
 496                          pmac_i2c_mode_combined);
 497         rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
 498                            0xd0 | pmac_i2c_read,
 499                            1, 0x81, &data, 1);
 500         if (rc != 0)
 501                 goto bail;
 502
 503         data = (data & 0xf3) | (freeze ? 0x00 : 0x0c);
 504
 505         pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
 506         rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
 507                            0xd0 | pmac_i2c_write,
 508                            1, 0x81, &data, 1);
 509
 510  bail:
 511         if (rc != 0) {
 512                 printk("Cypress Timebase %s rc: %d\n",
 513                        freeze ? "freeze" : "unfreeze", rc);
 514                 panic("Timebase freeze failed !\n");
 515         }
 516 }
 517
 518
 519 static void smp_core99_pulsar_tb_freeze(int freeze)
 520 {
 521         u8 data;
 522         int rc;
 523
 524         pmac_i2c_setmode(pmac_tb_clock_chip_host,
 525                          pmac_i2c_mode_combined);
 526         rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
 527                            pmac_tb_pulsar_addr | pmac_i2c_read,
 528                            1, 0x2e, &data, 1);
 529         if (rc != 0)
 530                 goto bail;
 531
 532         data = (data & 0x88) | (freeze ? 0x11 : 0x22);
 533
 534         pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
 535         rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
 536                            pmac_tb_pulsar_addr | pmac_i2c_write,
 537                            1, 0x2e, &data, 1);
 538  bail:
 539         if (rc != 0) {
 540                 printk(KERN_ERR "Pulsar Timebase %s rc: %d\n",
 541                        freeze ? "freeze" : "unfreeze", rc);
 542                 panic("Timebase freeze failed !\n");
 543         }
 544 }
 545
 546 static void __init smp_core99_setup_i2c_hwsync(int ncpus)
 547 {
 548         struct device_node *cc = NULL;
 549         struct device_node *p;
 550         const char *name = NULL;
 551         u32 *reg;
 552         int ok;
 553
 554         /* Look for the clock chip */
 555         while ((cc = of_find_node_by_name(cc, "i2c-hwclock")) != NULL) {
 556                 p = of_get_parent(cc);
 557                 ok = p && device_is_compatible(p, "uni-n-i2c");
 558                 of_node_put(p);
 559                 if (!ok)
 560                         continue;
 561
 562                 pmac_tb_clock_chip_host = pmac_i2c_find_bus(cc);
 563                 if (pmac_tb_clock_chip_host == NULL)
 564                         continue;
 565                 reg = (u32 *)get_property(cc, "reg", NULL);
 566                 if (reg == NULL)
 567                         continue;
 568                 switch (*reg) {
 569                 case 0xd2:
 570                         if (device_is_compatible(cc,"pulsar-legacy-slewing")) {
 571                                 pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
 572                                 pmac_tb_pulsar_addr = 0xd2;
 573                                 name = "Pulsar";
 574                         } else if (device_is_compatible(cc, "cy28508")) {
 575                                 pmac_tb_freeze = smp_core99_cypress_tb_freeze;
 576                                 name = "Cypress";
 577                         }
 578                         break;
 579                 case 0xd4:
 580                         pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
 581                         pmac_tb_pulsar_addr = 0xd4;
 582                         name = "Pulsar";
 583                         break;
 584                 }
 585                 if (pmac_tb_freeze != NULL)
 586                         break;
 587         }
 588         if (pmac_tb_freeze != NULL) {
 589                 /* Open i2c bus for synchronous access */
 590                 if (pmac_i2c_open(pmac_tb_clock_chip_host, 1)) {
 591                         printk(KERN_ERR "Failed top open i2c bus for clock"
 592                                " sync, fallback to software sync !\n");
 593                         goto no_i2c_sync;
 594                 }
 595                 printk(KERN_INFO "Processor timebase sync using %s i2c clock\n",
 596                        name);
 597                 return;
 598         }
 599  no_i2c_sync:
 600         pmac_tb_freeze = NULL;
 601         pmac_tb_clock_chip_host = NULL;
 602 }
 603
 604
 605
 606 /*
 607  * Newer G5s uses a platform function
 608  */
 609
 610 static void smp_core99_pfunc_tb_freeze(int freeze)
 611 {
 612         struct device_node *cpus;
 613         struct pmf_args args;
 614
 615         cpus = of_find_node_by_path("/cpus");
 616         BUG_ON(cpus == NULL);
 617         args.count = 1;
 618         args.u[0].v = !freeze;
 619         pmf_call_function(cpus, "cpu-timebase", &args);
 620         of_node_put(cpus);
 621 }
 622
 623 #else /* CONFIG_PPC64 */
 624
 625 /*
 626  * SMP G4 use a GPIO to enable/disable the timebase.
 627  */
 628
 629 static unsigned int core99_tb_gpio;     /* Timebase freeze GPIO */
 630
 631 static void smp_core99_gpio_tb_freeze(int freeze)
 632 {
 633         if (freeze)
 634                 pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
 635         else
 636                 pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
 637         pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
 638 }
 639
 640
 641 #endif /* !CONFIG_PPC64 */
 642
 643 /* L2 and L3 cache settings to pass from CPU0 to CPU1 on G4 cpus */
 644 volatile static long int core99_l2_cache;
 645 volatile static long int core99_l3_cache;
 646
 647 static void __devinit core99_init_caches(int cpu)
 648 {
 649 #ifndef CONFIG_PPC64
 650         if (!cpu_has_feature(CPU_FTR_L2CR))
 651                 return;
 652
 653         if (cpu == 0) {
 654                 core99_l2_cache = _get_L2CR();
 655                 printk("CPU0: L2CR is %lx\n", core99_l2_cache);
 656         } else {
 657                 printk("CPU%d: L2CR was %lx\n", cpu, _get_L2CR());
 658                 _set_L2CR(0);
 659                 _set_L2CR(core99_l2_cache);
 660                 printk("CPU%d: L2CR set to %lx\n", cpu, core99_l2_cache);
 661         }
 662
 663         if (!cpu_has_feature(CPU_FTR_L3CR))
 664                 return;
 665
 666         if (cpu == 0){
 667                 core99_l3_cache = _get_L3CR();
 668                 printk("CPU0: L3CR is %lx\n", core99_l3_cache);
 669         } else {
 670                 printk("CPU%d: L3CR was %lx\n", cpu, _get_L3CR());
 671                 _set_L3CR(0);
 672                 _set_L3CR(core99_l3_cache);
 673                 printk("CPU%d: L3CR set to %lx\n", cpu, core99_l3_cache);
 674         }
 675 #endif /* !CONFIG_PPC64 */
 676 }
 677
 678 static void __init smp_core99_setup(int ncpus)
 679 {
 680 #ifdef CONFIG_PPC64
 681
 682         /* i2c based HW sync on some G5s */
 683         if (machine_is_compatible("PowerMac7,2") ||
 684             machine_is_compatible("PowerMac7,3") ||
 685             machine_is_compatible("RackMac3,1"))
 686                 smp_core99_setup_i2c_hwsync(ncpus);
 687
 688         /* pfunc based HW sync on recent G5s */
 689         if (pmac_tb_freeze == NULL) {
 690                 struct device_node *cpus =
 691                         of_find_node_by_path("/cpus");
 692                 if (cpus &&
 693                     get_property(cpus, "platform-cpu-timebase", NULL)) {
 694                         pmac_tb_freeze = smp_core99_pfunc_tb_freeze;
 695                         printk(KERN_INFO "Processor timebase sync using"
 696                                " platform function\n");
 697                 }
 698         }
 699
 700 #else /* CONFIG_PPC64 */
 701
 702         /* GPIO based HW sync on ppc32 Core99 */
 703         if (pmac_tb_freeze == NULL && !machine_is_compatible("MacRISC4")) {
 704                 struct device_node *cpu;
 705                 u32 *tbprop = NULL;
 706
 707                 core99_tb_gpio = KL_GPIO_TB_ENABLE;     /* default value */
 708                 cpu = of_find_node_by_type(NULL, "cpu");
 709                 if (cpu != NULL) {
 710                         tbprop = (u32 *)get_property(cpu, "timebase-enable",
 711                                                      NULL);
 712                         if (tbprop)
 713                                 core99_tb_gpio = *tbprop;
 714                         of_node_put(cpu);
 715                 }
 716                 pmac_tb_freeze = smp_core99_gpio_tb_freeze;
 717                 printk(KERN_INFO "Processor timebase sync using"
 718                        " GPIO 0x%02x\n", core99_tb_gpio);
 719         }
 720
 721 #endif /* CONFIG_PPC64 */
 722
 723         /* No timebase sync, fallback to software */
 724         if (pmac_tb_freeze == NULL) {
 725                 smp_ops->give_timebase = smp_generic_give_timebase;
 726                 smp_ops->take_timebase = smp_generic_take_timebase;
 727                 printk(KERN_INFO "Processor timebase sync using software\n");
 728         }
 729
 730 #ifndef CONFIG_PPC64
 731         {
 732                 int i;
 733
 734                 /* XXX should get this from reg properties */
 735                 for (i = 1; i < ncpus; ++i)
 736                         smp_hw_index[i] = i;
 737         }
 738 #endif
 739
 740         /* 32 bits SMP can't NAP */
 741         if (!machine_is_compatible("MacRISC4"))
 742                 powersave_nap = 0;
 743 }
 744
 745 static int __init smp_core99_probe(void)
 746 {
 747         struct device_node *cpus;
 748         int ncpus = 0;
 749
 750         if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
 751
 752         /* Count CPUs in the device-tree */
 753         for (cpus = NULL; (cpus = of_find_node_by_type(cpus, "cpu")) != NULL;)
 754                 ++ncpus;
 755
 756         printk(KERN_INFO "PowerMac SMP probe found %d cpus\n", ncpus);
 757
 758         /* Nothing more to do if less than 2 of them */
 759         if (ncpus <= 1)
 760                 return 1;
 761
 762         /* We need to perform some early initialisations before we can start
 763          * setting up SMP as we are running before initcalls
 764          */
 765         pmac_pfunc_base_install();
 766         pmac_i2c_init();
 767
 768         /* Setup various bits like timebase sync method, ability to nap, ... */
 769         smp_core99_setup(ncpus);
 770
 771         /* Install IPIs */
 772         mpic_request_ipis();
 773
 774         /* Collect l2cr and l3cr values from CPU 0 */
 775         core99_init_caches(0);
 776
 777         return ncpus;
 778 }
 779
 780 static void __devinit smp_core99_kick_cpu(int nr)
 781 {
 782         unsigned int save_vector;
 783         unsigned long target, flags;
 784         volatile unsigned int *vector
 785                  = ((volatile unsigned int *)(KERNELBASE+0x100));
 786
 787         if (nr < 0 || nr > 3)
 788                 return;
 789
 790         if (ppc_md.progress)
 791                 ppc_md.progress("smp_core99_kick_cpu", 0x346);
 792
 793         local_irq_save(flags);
 794         local_irq_disable();
 795
 796         /* Save reset vector */
 797         save_vector = *vector;
 798
 799         /* Setup fake reset vector that does
 800          *   b __secondary_start_pmac_0 + nr*8 - KERNELBASE
 801          */
 802         target = (unsigned long) __secondary_start_pmac_0 + nr * 8;
 803         create_branch((unsigned long)vector, target, BRANCH_SET_LINK);
 804
 805         /* Put some life in our friend */
 806         pmac_call_feature(PMAC_FTR_RESET_CPU, NULL, nr, 0);
 807
 808         /* FIXME: We wait a bit for the CPU to take the exception, I should
 809          * instead wait for the entry code to set something for me. Well,
 810          * ideally, all that crap will be done in prom.c and the CPU left
 811          * in a RAM-based wait loop like CHRP.
 812          */
 813         mdelay(1);
 814
 815         /* Restore our exception vector */
 816         *vector = save_vector;
 817         flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
 818
 819         local_irq_restore(flags);
 820         if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu done", 0x347);
 821 }
 822
 823 static void __devinit smp_core99_setup_cpu(int cpu_nr)
 824 {
 825         /* Setup L2/L3 */
 826         if (cpu_nr != 0)
 827                 core99_init_caches(cpu_nr);
 828
 829         /* Setup openpic */
 830         mpic_setup_this_cpu();
 831
 832         if (cpu_nr == 0) {
 833 #ifdef CONFIG_PPC64
 834                 extern void g5_phy_disable_cpu1(void);
 835
 836                 /* Close i2c bus if it was used for tb sync */
 837                 if (pmac_tb_clock_chip_host) {
 838                         pmac_i2c_close(pmac_tb_clock_chip_host);
 839                         pmac_tb_clock_chip_host = NULL;
 840                 }
 841
 842                 /* If we didn't start the second CPU, we must take
 843                  * it off the bus
 844                  */
 845                 if (machine_is_compatible("MacRISC4") &&
 846                     num_online_cpus() < 2)
 847                         g5_phy_disable_cpu1();
 848 #endif /* CONFIG_PPC64 */
 849
 850                 if (ppc_md.progress)
 851                         ppc_md.progress("core99_setup_cpu 0 done", 0x349);
 852         }
 853 }
 854
 855
 856 #if defined(CONFIG_HOTPLUG_CPU) && defined(CONFIG_PPC32)
 857
 858 int smp_core99_cpu_disable(void)
 859 {
 860         cpu_clear(smp_processor_id(), cpu_online_map);
 861
 862         /* XXX reset cpu affinity here */
 863         mpic_cpu_set_priority(0xf);
 864         asm volatile("mtdec %0" : : "r" (0x7fffffff));
 865         mb();
 866         udelay(20);
 867         asm volatile("mtdec %0" : : "r" (0x7fffffff));
 868         return 0;
 869 }
 870
 871 extern void low_cpu_die(void) __attribute__((noreturn)); /* in sleep.S */
 872 static int cpu_dead[NR_CPUS];
 873
 874 void cpu_die(void)
 875 {
 876         local_irq_disable();
 877         cpu_dead[smp_processor_id()] = 1;
 878         mb();
 879         low_cpu_die();
 880 }
 881
 882 void smp_core99_cpu_die(unsigned int cpu)
 883 {
 884         int timeout;
 885
 886         timeout = 1000;
 887         while (!cpu_dead[cpu]) {
 888                 if (--timeout == 0) {
 889                         printk("CPU %u refused to die!\n", cpu);
 890                         break;
 891                 }
 892                 msleep(1);
 893         }
 894         cpu_dead[cpu] = 0;
 895 }
 896
 897 #endif
 898
 899 /* Core99 Macs (dual G4s and G5s) */
 900 struct smp_ops_t core99_smp_ops = {
 901         .message_pass   = smp_mpic_message_pass,
 902         .probe          = smp_core99_probe,
 903         .kick_cpu       = smp_core99_kick_cpu,
 904         .setup_cpu      = smp_core99_setup_cpu,
 905         .give_timebase  = smp_core99_give_timebase,
 906         .take_timebase  = smp_core99_take_timebase,
 907 #if defined(CONFIG_HOTPLUG_CPU) && defined(CONFIG_PPC32)
 908         .cpu_disable    = smp_core99_cpu_disable,
 909         .cpu_die        = smp_core99_cpu_die,
 910 #endif
 911 };