release/src-rt-6.x.4708/linux/linux-2.6.36/arch/powerpc/kernel/setup-common.c

   1 /*
   2  * Common boot and setup code for both 32-bit and 64-bit.
   3  * Extracted from arch/powerpc/kernel/setup_64.c.
   4  *
   5  * Copyright (C) 2001 PPC64 Team, IBM Corp
   6  *
   7  *      This program is free software; you can redistribute it and/or
   8  *      modify it under the terms of the GNU General Public License
   9  *      as published by the Free Software Foundation; either version
  10  *      2 of the License, or (at your option) any later version.
  11  */
  12
  13 #undef DEBUG
  14
  15 #include <linux/module.h>
  16 #include <linux/string.h>
  17 #include <linux/sched.h>
  18 #include <linux/init.h>
  19 #include <linux/kernel.h>
  20 #include <linux/reboot.h>
  21 #include <linux/delay.h>
  22 #include <linux/initrd.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/seq_file.h>
  25 #include <linux/ioport.h>
  26 #include <linux/console.h>
  27 #include <linux/screen_info.h>
  28 #include <linux/root_dev.h>
  29 #include <linux/notifier.h>
  30 #include <linux/cpu.h>
  31 #include <linux/unistd.h>
  32 #include <linux/serial.h>
  33 #include <linux/serial_8250.h>
  34 #include <linux/debugfs.h>
  35 #include <linux/percpu.h>
  36 #include <linux/memblock.h>
  37 #include <linux/of_platform.h>
  38 #include <asm/io.h>
  39 #include <asm/paca.h>
  40 #include <asm/prom.h>
  41 #include <asm/processor.h>
  42 #include <asm/vdso_datapage.h>
  43 #include <asm/pgtable.h>
  44 #include <asm/smp.h>
  45 #include <asm/elf.h>
  46 #include <asm/machdep.h>
  47 #include <asm/time.h>
  48 #include <asm/cputable.h>
  49 #include <asm/sections.h>
  50 #include <asm/firmware.h>
  51 #include <asm/btext.h>
  52 #include <asm/nvram.h>
  53 #include <asm/setup.h>
  54 #include <asm/system.h>
  55 #include <asm/rtas.h>
  56 #include <asm/iommu.h>
  57 #include <asm/serial.h>
  58 #include <asm/cache.h>
  59 #include <asm/page.h>
  60 #include <asm/mmu.h>
  61 #include <asm/xmon.h>
  62 #include <asm/cputhreads.h>
  63 #include <mm/mmu_decl.h>
  64
  65 #include "setup.h"
  66
  67 #ifdef DEBUG
  68 #include <asm/udbg.h>
  69 #define DBG(fmt...) udbg_printf(fmt)
  70 #else
  71 #define DBG(fmt...)
  72 #endif
  73
  74 /* The main machine-dep calls structure
  75  */
  76 struct machdep_calls ppc_md;
  77 EXPORT_SYMBOL(ppc_md);
  78 struct machdep_calls *machine_id;
  79 EXPORT_SYMBOL(machine_id);
  80
  81 unsigned long klimit = (unsigned long) _end;
  82
  83 char cmd_line[COMMAND_LINE_SIZE];
  84
  85 /*
  86  * This still seems to be needed... -- paulus
  87  */
  88 struct screen_info screen_info = {
  89         .orig_x = 0,
  90         .orig_y = 25,
  91         .orig_video_cols = 80,
  92         .orig_video_lines = 25,
  93         .orig_video_isVGA = 1,
  94         .orig_video_points = 16
  95 };
  96
  97 /* Variables required to store legacy IO irq routing */
  98 int of_i8042_kbd_irq;
  99 EXPORT_SYMBOL_GPL(of_i8042_kbd_irq);
 100 int of_i8042_aux_irq;
 101 EXPORT_SYMBOL_GPL(of_i8042_aux_irq);
 102
 103 #ifdef __DO_IRQ_CANON
 104 int ppc_do_canonicalize_irqs;
 105 EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
 106 #endif
 107
 108 /* also used by kexec */
 109 void machine_shutdown(void)
 110 {
 111         if (ppc_md.machine_shutdown)
 112                 ppc_md.machine_shutdown();
 113 }
 114
 115 void machine_restart(char *cmd)
 116 {
 117         machine_shutdown();
 118         if (ppc_md.restart)
 119                 ppc_md.restart(cmd);
 120 #ifdef CONFIG_SMP
 121         smp_send_stop();
 122 #endif
 123         printk(KERN_EMERG "System Halted, OK to turn off power\n");
 124         local_irq_disable();
 125         while (1) ;
 126 }
 127
 128 void machine_power_off(void)
 129 {
 130         machine_shutdown();
 131         if (ppc_md.power_off)
 132                 ppc_md.power_off();
 133 #ifdef CONFIG_SMP
 134         smp_send_stop();
 135 #endif
 136         printk(KERN_EMERG "System Halted, OK to turn off power\n");
 137         local_irq_disable();
 138         while (1) ;
 139 }
 140 /* Used by the G5 thermal driver */
 141 EXPORT_SYMBOL_GPL(machine_power_off);
 142
 143 void (*pm_power_off)(void) = machine_power_off;
 144 EXPORT_SYMBOL_GPL(pm_power_off);
 145
 146 void machine_halt(void)
 147 {
 148         machine_shutdown();
 149         if (ppc_md.halt)
 150                 ppc_md.halt();
 151 #ifdef CONFIG_SMP
 152         smp_send_stop();
 153 #endif
 154         printk(KERN_EMERG "System Halted, OK to turn off power\n");
 155         local_irq_disable();
 156         while (1) ;
 157 }
 158
 159
 160 #ifdef CONFIG_TAU
 161 extern u32 cpu_temp(unsigned long cpu);
 162 extern u32 cpu_temp_both(unsigned long cpu);
 163 #endif /* CONFIG_TAU */
 164
 165 #ifdef CONFIG_SMP
 166 DEFINE_PER_CPU(unsigned int, cpu_pvr);
 167 #endif
 168
 169 static void show_cpuinfo_summary(struct seq_file *m)
 170 {
 171         struct device_node *root;
 172         const char *model = NULL;
 173 #if defined(CONFIG_SMP) && defined(CONFIG_PPC32)
 174         unsigned long bogosum = 0;
 175         int i;
 176         for_each_online_cpu(i)
 177                 bogosum += loops_per_jiffy;
 178         seq_printf(m, "total bogomips\t: %lu.%02lu\n",
 179                    bogosum/(500000/HZ), bogosum/(5000/HZ) % 100);
 180 #endif /* CONFIG_SMP && CONFIG_PPC32 */
 181         seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
 182         if (ppc_md.name)
 183                 seq_printf(m, "platform\t: %s\n", ppc_md.name);
 184         root = of_find_node_by_path("/");
 185         if (root)
 186                 model = of_get_property(root, "model", NULL);
 187         if (model)
 188                 seq_printf(m, "model\t\t: %s\n", model);
 189         of_node_put(root);
 190
 191         if (ppc_md.show_cpuinfo != NULL)
 192                 ppc_md.show_cpuinfo(m);
 193
 194 #ifdef CONFIG_PPC32
 195         /* Display the amount of memory */
 196         seq_printf(m, "Memory\t\t: %d MB\n",
 197                    (unsigned int)(total_memory / (1024 * 1024)));
 198 #endif
 199 }
 200
 201 static int show_cpuinfo(struct seq_file *m, void *v)
 202 {
 203         unsigned long cpu_id = (unsigned long)v - 1;
 204         unsigned int pvr;
 205         unsigned short maj;
 206         unsigned short min;
 207
 208         /* We only show online cpus: disable preempt (overzealous, I
 209          * knew) to prevent cpu going down. */
 210         preempt_disable();
 211         if (!cpu_online(cpu_id)) {
 212                 preempt_enable();
 213                 return 0;
 214         }
 215
 216 #ifdef CONFIG_SMP
 217         pvr = per_cpu(cpu_pvr, cpu_id);
 218 #else
 219         pvr = mfspr(SPRN_PVR);
 220 #endif
 221         maj = (pvr >> 8) & 0xFF;
 222         min = pvr & 0xFF;
 223
 224         seq_printf(m, "processor\t: %lu\n", cpu_id);
 225         seq_printf(m, "cpu\t\t: ");
 226
 227         if (cur_cpu_spec->pvr_mask)
 228                 seq_printf(m, "%s", cur_cpu_spec->cpu_name);
 229         else
 230                 seq_printf(m, "unknown (%08x)", pvr);
 231
 232 #ifdef CONFIG_ALTIVEC
 233         if (cpu_has_feature(CPU_FTR_ALTIVEC))
 234                 seq_printf(m, ", altivec supported");
 235 #endif /* CONFIG_ALTIVEC */
 236
 237         seq_printf(m, "\n");
 238
 239 #ifdef CONFIG_TAU
 240         if (cur_cpu_spec->cpu_features & CPU_FTR_TAU) {
 241 #ifdef CONFIG_TAU_AVERAGE
 242                 /* more straightforward, but potentially misleading */
 243                 seq_printf(m,  "temperature \t: %u C (uncalibrated)\n",
 244                            cpu_temp(cpu_id));
 245 #else
 246                 /* show the actual temp sensor range */
 247                 u32 temp;
 248                 temp = cpu_temp_both(cpu_id);
 249                 seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
 250                            temp & 0xff, temp >> 16);
 251 #endif
 252         }
 253 #endif /* CONFIG_TAU */
 254
 255         /*
 256          * Assume here that all clock rates are the same in a
 257          * smp system.  -- Cort
 258          */
 259         if (ppc_proc_freq)
 260                 seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
 261                            ppc_proc_freq / 1000000, ppc_proc_freq % 1000000);
 262
 263         if (ppc_md.show_percpuinfo != NULL)
 264                 ppc_md.show_percpuinfo(m, cpu_id);
 265
 266         /* If we are a Freescale core do a simple check so
 267          * we dont have to keep adding cases in the future */
 268         if (PVR_VER(pvr) & 0x8000) {
 269                 switch (PVR_VER(pvr)) {
 270                 case 0x8000:    /* 7441/7450/7451, Voyager */
 271                 case 0x8001:    /* 7445/7455, Apollo 6 */
 272                 case 0x8002:    /* 7447/7457, Apollo 7 */
 273                 case 0x8003:    /* 7447A, Apollo 7 PM */
 274                 case 0x8004:    /* 7448, Apollo 8 */
 275                 case 0x800c:    /* 7410, Nitro */
 276                         maj = ((pvr >> 8) & 0xF);
 277                         min = PVR_MIN(pvr);
 278                         break;
 279                 default:        /* e500/book-e */
 280                         maj = PVR_MAJ(pvr);
 281                         min = PVR_MIN(pvr);
 282                         break;
 283                 }
 284         } else {
 285                 switch (PVR_VER(pvr)) {
 286                         case 0x0020:    /* 403 family */
 287                                 maj = PVR_MAJ(pvr) + 1;
 288                                 min = PVR_MIN(pvr);
 289                                 break;
 290                         case 0x1008:    /* 740P/750P ?? */
 291                                 maj = ((pvr >> 8) & 0xFF) - 1;
 292                                 min = pvr & 0xFF;
 293                                 break;
 294                         default:
 295                                 maj = (pvr >> 8) & 0xFF;
 296                                 min = pvr & 0xFF;
 297                                 break;
 298                 }
 299         }
 300
 301         seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
 302                    maj, min, PVR_VER(pvr), PVR_REV(pvr));
 303
 304 #ifdef CONFIG_PPC32
 305         seq_printf(m, "bogomips\t: %lu.%02lu\n",
 306                    loops_per_jiffy / (500000/HZ),
 307                    (loops_per_jiffy / (5000/HZ)) % 100);
 308 #endif
 309
 310 #ifdef CONFIG_SMP
 311         seq_printf(m, "\n");
 312 #endif
 313
 314         preempt_enable();
 315
 316         /* If this is the last cpu, print the summary */
 317         if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids)
 318                 show_cpuinfo_summary(m);
 319
 320         return 0;
 321 }
 322
 323 static void *c_start(struct seq_file *m, loff_t *pos)
 324 {
 325         if (*pos == 0)  /* just in case, cpu 0 is not the first */
 326                 *pos = cpumask_first(cpu_online_mask);
 327         else
 328                 *pos = cpumask_next(*pos - 1, cpu_online_mask);
 329         if ((*pos) < nr_cpu_ids)
 330                 return (void *)(unsigned long)(*pos + 1);
 331         return NULL;
 332 }
 333
 334 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 335 {
 336         (*pos)++;
 337         return c_start(m, pos);
 338 }
 339
 340 static void c_stop(struct seq_file *m, void *v)
 341 {
 342 }
 343
 344 const struct seq_operations cpuinfo_op = {
 345         .start =c_start,
 346         .next = c_next,
 347         .stop = c_stop,
 348         .show = show_cpuinfo,
 349 };
 350
 351 void __init check_for_initrd(void)
 352 {
 353 #ifdef CONFIG_BLK_DEV_INITRD
 354         DBG(" -> check_for_initrd()  initrd_start=0x%lx  initrd_end=0x%lx\n",
 355             initrd_start, initrd_end);
 356
 357         /* If we were passed an initrd, set the ROOT_DEV properly if the values
 358          * look sensible. If not, clear initrd reference.
 359          */
 360         if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
 361             initrd_end > initrd_start)
 362                 ROOT_DEV = Root_RAM0;
 363         else
 364                 initrd_start = initrd_end = 0;
 365
 366         if (initrd_start)
 367                 printk("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);
 368
 369         DBG(" <- check_for_initrd()\n");
 370 #endif /* CONFIG_BLK_DEV_INITRD */
 371 }
 372
 373 #ifdef CONFIG_SMP
 374
 375 int threads_per_core, threads_shift;
 376 cpumask_t threads_core_mask;
 377
 378 static void __init cpu_init_thread_core_maps(int tpc)
 379 {
 380         int i;
 381
 382         threads_per_core = tpc;
 383         threads_core_mask = CPU_MASK_NONE;
 384
 385         /* This implementation only supports power of 2 number of threads
 386          * for simplicity and performance
 387          */
 388         threads_shift = ilog2(tpc);
 389         BUG_ON(tpc != (1 << threads_shift));
 390
 391         for (i = 0; i < tpc; i++)
 392                 cpu_set(i, threads_core_mask);
 393
 394         printk(KERN_INFO "CPU maps initialized for %d thread%s per core\n",
 395                tpc, tpc > 1 ? "s" : "");
 396         printk(KERN_DEBUG " (thread shift is %d)\n", threads_shift);
 397 }
 398
 399
 400 /**
 401  * setup_cpu_maps - initialize the following cpu maps:
 402  *                  cpu_possible_mask
 403  *                  cpu_present_mask
 404  *
 405  * Having the possible map set up early allows us to restrict allocations
 406  * of things like irqstacks to num_possible_cpus() rather than NR_CPUS.
 407  *
 408  * We do not initialize the online map here; cpus set their own bits in
 409  * cpu_online_mask as they come up.
 410  *
 411  * This function is valid only for Open Firmware systems.  finish_device_tree
 412  * must be called before using this.
 413  *
 414  * While we're here, we may as well set the "physical" cpu ids in the paca.
 415  *
 416  * NOTE: This must match the parsing done in early_init_dt_scan_cpus.
 417  */
 418 void __init smp_setup_cpu_maps(void)
 419 {
 420         struct device_node *dn = NULL;
 421         int cpu = 0;
 422         int nthreads = 1;
 423
 424         DBG("smp_setup_cpu_maps()\n");
 425
 426         while ((dn = of_find_node_by_type(dn, "cpu")) && cpu < NR_CPUS) {
 427                 const int *intserv;
 428                 int j, len;
 429
 430                 DBG("  * %s...\n", dn->full_name);
 431
 432                 intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
 433                                 &len);
 434                 if (intserv) {
 435                         nthreads = len / sizeof(int);
 436                         DBG("    ibm,ppc-interrupt-server#s -> %d threads\n",
 437                             nthreads);
 438                 } else {
 439                         DBG("    no ibm,ppc-interrupt-server#s -> 1 thread\n");
 440                         intserv = of_get_property(dn, "reg", NULL);
 441                         if (!intserv)
 442                                 intserv = &cpu; /* assume logical == phys */
 443                 }
 444
 445                 for (j = 0; j < nthreads && cpu < NR_CPUS; j++) {
 446                         DBG("    thread %d -> cpu %d (hard id %d)\n",
 447                             j, cpu, intserv[j]);
 448                         set_cpu_present(cpu, true);
 449                         set_hard_smp_processor_id(cpu, intserv[j]);
 450                         set_cpu_possible(cpu, true);
 451                         cpu++;
 452                 }
 453         }
 454
 455         /* If no SMT supported, nthreads is forced to 1 */
 456         if (!cpu_has_feature(CPU_FTR_SMT)) {
 457                 DBG("  SMT disabled ! nthreads forced to 1\n");
 458                 nthreads = 1;
 459         }
 460
 461 #ifdef CONFIG_PPC64
 462         /*
 463          * On pSeries LPAR, we need to know how many cpus
 464          * could possibly be added to this partition.
 465          */
 466         if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR) &&
 467             (dn = of_find_node_by_path("/rtas"))) {
 468                 int num_addr_cell, num_size_cell, maxcpus;
 469                 const unsigned int *ireg;
 470
 471                 num_addr_cell = of_n_addr_cells(dn);
 472                 num_size_cell = of_n_size_cells(dn);
 473
 474                 ireg = of_get_property(dn, "ibm,lrdr-capacity", NULL);
 475
 476                 if (!ireg)
 477                         goto out;
 478
 479                 maxcpus = ireg[num_addr_cell + num_size_cell];
 480
 481                 /* Double maxcpus for processors which have SMT capability */
 482                 if (cpu_has_feature(CPU_FTR_SMT))
 483                         maxcpus *= nthreads;
 484
 485                 if (maxcpus > NR_CPUS) {
 486                         printk(KERN_WARNING
 487                                "Partition configured for %d cpus, "
 488                                "operating system maximum is %d.\n",
 489                                maxcpus, NR_CPUS);
 490                         maxcpus = NR_CPUS;
 491                 } else
 492                         printk(KERN_INFO "Partition configured for %d cpus.\n",
 493                                maxcpus);
 494
 495                 for (cpu = 0; cpu < maxcpus; cpu++)
 496                         set_cpu_possible(cpu, true);
 497         out:
 498                 of_node_put(dn);
 499         }
 500         vdso_data->processorCount = num_present_cpus();
 501 #endif /* CONFIG_PPC64 */
 502
 503         /* Initialize CPU <=> thread mapping/
 504          *
 505          * WARNING: We assume that the number of threads is the same for
 506          * every CPU in the system. If that is not the case, then some code
 507          * here will have to be reworked
 508          */
 509         cpu_init_thread_core_maps(nthreads);
 510
 511         free_unused_pacas();
 512 }
 513 #endif /* CONFIG_SMP */
 514
 515 #ifdef CONFIG_PCSPKR_PLATFORM
 516 static __init int add_pcspkr(void)
 517 {
 518         struct device_node *np;
 519         struct platform_device *pd;
 520         int ret;
 521
 522         np = of_find_compatible_node(NULL, NULL, "pnpPNP,100");
 523         of_node_put(np);
 524         if (!np)
 525                 return -ENODEV;
 526
 527         pd = platform_device_alloc("pcspkr", -1);
 528         if (!pd)
 529                 return -ENOMEM;
 530
 531         ret = platform_device_add(pd);
 532         if (ret)
 533                 platform_device_put(pd);
 534
 535         return ret;
 536 }
 537 device_initcall(add_pcspkr);
 538 #endif  /* CONFIG_PCSPKR_PLATFORM */
 539
 540 void probe_machine(void)
 541 {
 542         extern struct machdep_calls __machine_desc_start;
 543         extern struct machdep_calls __machine_desc_end;
 544
 545         /*
 546          * Iterate all ppc_md structures until we find the proper
 547          * one for the current machine type
 548          */
 549         DBG("Probing machine type ...\n");
 550
 551         for (machine_id = &__machine_desc_start;
 552              machine_id < &__machine_desc_end;
 553              machine_id++) {
 554                 DBG("  %s ...", machine_id->name);
 555                 memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
 556                 if (ppc_md.probe()) {
 557                         DBG(" match !\n");
 558                         break;
 559                 }
 560                 DBG("\n");
 561         }
 562         /* What can we do if we didn't find ? */
 563         if (machine_id >= &__machine_desc_end) {
 564                 DBG("No suitable machine found !\n");
 565                 for (;;);
 566         }
 567
 568         printk(KERN_INFO "Using %s machine description\n", ppc_md.name);
 569 }
 570
 571 /* Match a class of boards, not a specific device configuration. */
 572 int check_legacy_ioport(unsigned long base_port)
 573 {
 574         struct device_node *parent, *np = NULL;
 575         int ret = -ENODEV;
 576
 577         switch(base_port) {
 578         case I8042_DATA_REG:
 579                 if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
 580                         np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
 581                 if (np) {
 582                         parent = of_get_parent(np);
 583
 584                         of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
 585                         if (!of_i8042_kbd_irq)
 586                                 of_i8042_kbd_irq = 1;
 587
 588                         of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
 589                         if (!of_i8042_aux_irq)
 590                                 of_i8042_aux_irq = 12;
 591
 592                         of_node_put(np);
 593                         np = parent;
 594                         break;
 595                 }
 596                 np = of_find_node_by_type(NULL, "8042");
 597                 /* Pegasos has no device_type on its 8042 node, look for the
 598                  * name instead */
 599                 if (!np)
 600                         np = of_find_node_by_name(NULL, "8042");
 601                 break;
 602         case FDC_BASE: /* FDC1 */
 603                 np = of_find_node_by_type(NULL, "fdc");
 604                 break;
 605 #ifdef CONFIG_PPC_PREP
 606         case _PIDXR:
 607         case _PNPWRP:
 608         case PNPBIOS_BASE:
 609                 /* implement me */
 610 #endif
 611         default:
 612                 /* ipmi is supposed to fail here */
 613                 break;
 614         }
 615         if (!np)
 616                 return ret;
 617         parent = of_get_parent(np);
 618         if (parent) {
 619                 if (strcmp(parent->type, "isa") == 0)
 620                         ret = 0;
 621                 of_node_put(parent);
 622         }
 623         of_node_put(np);
 624         return ret;
 625 }
 626 EXPORT_SYMBOL(check_legacy_ioport);
 627
 628 static int ppc_panic_event(struct notifier_block *this,
 629                              unsigned long event, void *ptr)
 630 {
 631         ppc_md.panic(ptr);  /* May not return */
 632         return NOTIFY_DONE;
 633 }
 634
 635 static struct notifier_block ppc_panic_block = {
 636         .notifier_call = ppc_panic_event,
 637         .priority = INT_MIN /* may not return; must be done last */
 638 };
 639
 640 void __init setup_panic(void)
 641 {
 642         atomic_notifier_chain_register(&panic_notifier_list, &ppc_panic_block);
 643 }
 644
 645 #ifdef CONFIG_CHECK_CACHE_COHERENCY
 646 /*
 647  * For platforms that have configurable cache-coherency.  This function
 648  * checks that the cache coherency setting of the kernel matches the setting
 649  * left by the firmware, as indicated in the device tree.  Since a mismatch
 650  * will eventually result in DMA failures, we print * and error and call
 651  * BUG() in that case.
 652  */
 653
 654 #ifdef CONFIG_NOT_COHERENT_CACHE
 655 #define KERNEL_COHERENCY        0
 656 #else
 657 #define KERNEL_COHERENCY        1
 658 #endif
 659
 660 static int __init check_cache_coherency(void)
 661 {
 662         struct device_node *np;
 663         const void *prop;
 664         int devtree_coherency;
 665
 666         np = of_find_node_by_path("/");
 667         prop = of_get_property(np, "coherency-off", NULL);
 668         of_node_put(np);
 669
 670         devtree_coherency = prop ? 0 : 1;
 671
 672         if (devtree_coherency != KERNEL_COHERENCY) {
 673                 printk(KERN_ERR
 674                         "kernel coherency:%s != device tree_coherency:%s\n",
 675                         KERNEL_COHERENCY ? "on" : "off",
 676                         devtree_coherency ? "on" : "off");
 677                 BUG();
 678         }
 679
 680         return 0;
 681 }
 682
 683 late_initcall(check_cache_coherency);
 684 #endif /* CONFIG_CHECK_CACHE_COHERENCY */
 685
 686 #ifdef CONFIG_DEBUG_FS
 687 struct dentry *powerpc_debugfs_root;
 688 EXPORT_SYMBOL(powerpc_debugfs_root);
 689
 690 static int powerpc_debugfs_init(void)
 691 {
 692         powerpc_debugfs_root = debugfs_create_dir("powerpc", NULL);
 693
 694         return powerpc_debugfs_root == NULL;
 695 }
 696 arch_initcall(powerpc_debugfs_init);
 697 #endif
 698
 699 static int ppc_dflt_bus_notify(struct notifier_block *nb,
 700                                 unsigned long action, void *data)
 701 {
 702         struct device *dev = data;
 703
 704         /* We are only intereted in device addition */
 705         if (action != BUS_NOTIFY_ADD_DEVICE)
 706                 return 0;
 707
 708         set_dma_ops(dev, &dma_direct_ops);
 709
 710         return NOTIFY_DONE;
 711 }
 712
 713 static struct notifier_block ppc_dflt_plat_bus_notifier = {
 714         .notifier_call = ppc_dflt_bus_notify,
 715         .priority = INT_MAX,
 716 };
 717
 718 static int __init setup_bus_notifier(void)
 719 {
 720         bus_register_notifier(&platform_bus_type, &ppc_dflt_plat_bus_notifier);
 721         return 0;
 722 }
 723
 724 arch_initcall(setup_bus_notifier);