arch/powerpc/kernel/setup_64.c

   1 /*
   2  *
   3  * Common boot and setup code.
   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/seq_file.h>
  24 #include <linux/ioport.h>
  25 #include <linux/console.h>
  26 #include <linux/utsname.h>
  27 #include <linux/tty.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/bootmem.h>
  35 #include <linux/pci.h>
  36 #include <linux/lockdep.h>
  37 #include <linux/lmb.h>
  38 #include <asm/io.h>
  39 #include <asm/kdump.h>
  40 #include <asm/prom.h>
  41 #include <asm/processor.h>
  42 #include <asm/pgtable.h>
  43 #include <asm/smp.h>
  44 #include <asm/elf.h>
  45 #include <asm/machdep.h>
  46 #include <asm/paca.h>
  47 #include <asm/time.h>
  48 #include <asm/cputable.h>
  49 #include <asm/sections.h>
  50 #include <asm/btext.h>
  51 #include <asm/nvram.h>
  52 #include <asm/setup.h>
  53 #include <asm/system.h>
  54 #include <asm/rtas.h>
  55 #include <asm/iommu.h>
  56 #include <asm/serial.h>
  57 #include <asm/cache.h>
  58 #include <asm/page.h>
  59 #include <asm/mmu.h>
  60 #include <asm/firmware.h>
  61 #include <asm/xmon.h>
  62 #include <asm/udbg.h>
  63 #include <asm/kexec.h>
  64 #include <asm/mmu_context.h>
  65
  66 #include "setup.h"
  67
  68 #ifdef DEBUG
  69 #define DBG(fmt...) udbg_printf(fmt)
  70 #else
  71 #define DBG(fmt...)
  72 #endif
  73
  74 int boot_cpuid = 0;
  75 u64 ppc64_pft_size;
  76
  77 /* Pick defaults since we might want to patch instructions
  78  * before we've read this from the device tree.
  79  */
  80 struct ppc64_caches ppc64_caches = {
  81         .dline_size = 0x40,
  82         .log_dline_size = 6,
  83         .iline_size = 0x40,
  84         .log_iline_size = 6
  85 };
  86 EXPORT_SYMBOL_GPL(ppc64_caches);
  87
  88 /*
  89  * These are used in binfmt_elf.c to put aux entries on the stack
  90  * for each elf executable being started.
  91  */
  92 int dcache_bsize;
  93 int icache_bsize;
  94 int ucache_bsize;
  95
  96 #ifdef CONFIG_SMP
  97
  98 static int smt_enabled_cmdline;
  99
 100 /* Look for ibm,smt-enabled OF option */
 101 static void check_smt_enabled(void)
 102 {
 103         struct device_node *dn;
 104         const char *smt_option;
 105
 106         /* Allow the command line to overrule the OF option */
 107         if (smt_enabled_cmdline)
 108                 return;
 109
 110         dn = of_find_node_by_path("/options");
 111
 112         if (dn) {
 113                 smt_option = of_get_property(dn, "ibm,smt-enabled", NULL);
 114
 115                 if (smt_option) {
 116                         if (!strcmp(smt_option, "on"))
 117                                 smt_enabled_at_boot = 1;
 118                         else if (!strcmp(smt_option, "off"))
 119                                 smt_enabled_at_boot = 0;
 120                 }
 121         }
 122 }
 123
 124 /* Look for smt-enabled= cmdline option */
 125 static int __init early_smt_enabled(char *p)
 126 {
 127         smt_enabled_cmdline = 1;
 128
 129         if (!p)
 130                 return 0;
 131
 132         if (!strcmp(p, "on") || !strcmp(p, "1"))
 133                 smt_enabled_at_boot = 1;
 134         else if (!strcmp(p, "off") || !strcmp(p, "0"))
 135                 smt_enabled_at_boot = 0;
 136
 137         return 0;
 138 }
 139 early_param("smt-enabled", early_smt_enabled);
 140
 141 #else
 142 #define check_smt_enabled()
 143 #endif /* CONFIG_SMP */
 144
 145 /*
 146  * Early initialization entry point. This is called by head.S
 147  * with MMU translation disabled. We rely on the "feature" of
 148  * the CPU that ignores the top 2 bits of the address in real
 149  * mode so we can access kernel globals normally provided we
 150  * only toy with things in the RMO region. From here, we do
 151  * some early parsing of the device-tree to setup out LMB
 152  * data structures, and allocate & initialize the hash table
 153  * and segment tables so we can start running with translation
 154  * enabled.
 155  *
 156  * It is this function which will call the probe() callback of
 157  * the various platform types and copy the matching one to the
 158  * global ppc_md structure. Your platform can eventually do
 159  * some very early initializations from the probe() routine, but
 160  * this is not recommended, be very careful as, for example, the
 161  * device-tree is not accessible via normal means at this point.
 162  */
 163
 164 void __init early_setup(unsigned long dt_ptr)
 165 {
 166         /* -------- printk is _NOT_ safe to use here ! ------- */
 167
 168         /* Identify CPU type */
 169         identify_cpu(0, mfspr(SPRN_PVR));
 170
 171         /* Assume we're on cpu 0 for now. Don't write to the paca yet! */
 172         initialise_paca(&boot_paca, 0);
 173         setup_paca(&boot_paca);
 174
 175         /* Initialize lockdep early or else spinlocks will blow */
 176         lockdep_init();
 177
 178         /* -------- printk is now safe to use ------- */
 179
 180         /* Enable early debugging if any specified (see udbg.h) */
 181         udbg_early_init();
 182
 183         DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
 184
 185         /*
 186          * Do early initialization using the flattened device
 187          * tree, such as retrieving the physical memory map or
 188          * calculating/retrieving the hash table size.
 189          */
 190         early_init_devtree(__va(dt_ptr));
 191
 192         /* Now we know the logical id of our boot cpu, setup the paca. */
 193         setup_paca(&paca[boot_cpuid]);
 194
 195         /* Fix up paca fields required for the boot cpu */
 196         get_paca()->cpu_start = 1;
 197
 198         /* Probe the machine type */
 199         probe_machine();
 200
 201         setup_kdump_trampoline();
 202
 203         DBG("Found, Initializing memory management...\n");
 204
 205         /* Initialize the hash table or TLB handling */
 206         early_init_mmu();
 207
 208         DBG(" <- early_setup()\n");
 209 }
 210
 211 #ifdef CONFIG_SMP
 212 void early_setup_secondary(void)
 213 {
 214         /* Mark interrupts enabled in PACA */
 215         get_paca()->soft_enabled = 0;
 216
 217         /* Initialize the hash table or TLB handling */
 218         early_init_mmu_secondary();
 219 }
 220
 221 #endif /* CONFIG_SMP */
 222
 223 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
 224 void smp_release_cpus(void)
 225 {
 226         unsigned long *ptr;
 227
 228         DBG(" -> smp_release_cpus()\n");
 229
 230         /* All secondary cpus are spinning on a common spinloop, release them
 231          * all now so they can start to spin on their individual paca
 232          * spinloops. For non SMP kernels, the secondary cpus never get out
 233          * of the common spinloop.
 234          */
 235
 236         ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
 237                         - PHYSICAL_START);
 238         *ptr = __pa(generic_secondary_smp_init);
 239         mb();
 240
 241         DBG(" <- smp_release_cpus()\n");
 242 }
 243 #endif /* CONFIG_SMP || CONFIG_KEXEC */
 244
 245 /*
 246  * Initialize some remaining members of the ppc64_caches and systemcfg
 247  * structures
 248  * (at least until we get rid of them completely). This is mostly some
 249  * cache informations about the CPU that will be used by cache flush
 250  * routines and/or provided to userland
 251  */
 252 static void __init initialize_cache_info(void)
 253 {
 254         struct device_node *np;
 255         unsigned long num_cpus = 0;
 256
 257         DBG(" -> initialize_cache_info()\n");
 258
 259         for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
 260                 num_cpus += 1;
 261
 262                 /* We're assuming *all* of the CPUs have the same
 263                  * d-cache and i-cache sizes... -Peter
 264                  */
 265
 266                 if ( num_cpus == 1 ) {
 267                         const u32 *sizep, *lsizep;
 268                         u32 size, lsize;
 269
 270                         size = 0;
 271                         lsize = cur_cpu_spec->dcache_bsize;
 272                         sizep = of_get_property(np, "d-cache-size", NULL);
 273                         if (sizep != NULL)
 274                                 size = *sizep;
 275                         lsizep = of_get_property(np, "d-cache-block-size", NULL);
 276                         /* fallback if block size missing */
 277                         if (lsizep == NULL)
 278                                 lsizep = of_get_property(np, "d-cache-line-size", NULL);
 279                         if (lsizep != NULL)
 280                                 lsize = *lsizep;
 281                         if (sizep == 0 || lsizep == 0)
 282                                 DBG("Argh, can't find dcache properties ! "
 283                                     "sizep: %p, lsizep: %p\n", sizep, lsizep);
 284
 285                         ppc64_caches.dsize = size;
 286                         ppc64_caches.dline_size = lsize;
 287                         ppc64_caches.log_dline_size = __ilog2(lsize);
 288                         ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
 289
 290                         size = 0;
 291                         lsize = cur_cpu_spec->icache_bsize;
 292                         sizep = of_get_property(np, "i-cache-size", NULL);
 293                         if (sizep != NULL)
 294                                 size = *sizep;
 295                         lsizep = of_get_property(np, "i-cache-block-size", NULL);
 296                         if (lsizep == NULL)
 297                                 lsizep = of_get_property(np, "i-cache-line-size", NULL);
 298                         if (lsizep != NULL)
 299                                 lsize = *lsizep;
 300                         if (sizep == 0 || lsizep == 0)
 301                                 DBG("Argh, can't find icache properties ! "
 302                                     "sizep: %p, lsizep: %p\n", sizep, lsizep);
 303
 304                         ppc64_caches.isize = size;
 305                         ppc64_caches.iline_size = lsize;
 306                         ppc64_caches.log_iline_size = __ilog2(lsize);
 307                         ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
 308                 }
 309         }
 310
 311         DBG(" <- initialize_cache_info()\n");
 312 }
 313
 314
 315 /*
 316  * Do some initial setup of the system.  The parameters are those which
 317  * were passed in from the bootloader.
 318  */
 319 void __init setup_system(void)
 320 {
 321         DBG(" -> setup_system()\n");
 322
 323         /* Apply the CPUs-specific and firmware specific fixups to kernel
 324          * text (nop out sections not relevant to this CPU or this firmware)
 325          */
 326         do_feature_fixups(cur_cpu_spec->cpu_features,
 327                           &__start___ftr_fixup, &__stop___ftr_fixup);
 328         do_feature_fixups(cur_cpu_spec->mmu_features,
 329                           &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
 330         do_feature_fixups(powerpc_firmware_features,
 331                           &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
 332         do_lwsync_fixups(cur_cpu_spec->cpu_features,
 333                          &__start___lwsync_fixup, &__stop___lwsync_fixup);
 334
 335         /*
 336          * Unflatten the device-tree passed by prom_init or kexec
 337          */
 338         unflatten_device_tree();
 339
 340         /*
 341          * Fill the ppc64_caches & systemcfg structures with informations
 342          * retrieved from the device-tree.
 343          */
 344         initialize_cache_info();
 345
 346 #ifdef CONFIG_PPC_RTAS
 347         /*
 348          * Initialize RTAS if available
 349          */
 350         rtas_initialize();
 351 #endif /* CONFIG_PPC_RTAS */
 352
 353         /*
 354          * Check if we have an initrd provided via the device-tree
 355          */
 356         check_for_initrd();
 357
 358         /*
 359          * Do some platform specific early initializations, that includes
 360          * setting up the hash table pointers. It also sets up some interrupt-mapping
 361          * related options that will be used by finish_device_tree()
 362          */
 363         if (ppc_md.init_early)
 364                 ppc_md.init_early();
 365
 366         /*
 367          * We can discover serial ports now since the above did setup the
 368          * hash table management for us, thus ioremap works. We do that early
 369          * so that further code can be debugged
 370          */
 371         find_legacy_serial_ports();
 372
 373         /*
 374          * Register early console
 375          */
 376         register_early_udbg_console();
 377
 378         /*
 379          * Initialize xmon
 380          */
 381         xmon_setup();
 382
 383         check_smt_enabled();
 384         smp_setup_cpu_maps();
 385
 386 #ifdef CONFIG_SMP
 387         /* Release secondary cpus out of their spinloops at 0x60 now that
 388          * we can map physical -> logical CPU ids
 389          */
 390         smp_release_cpus();
 391 #endif
 392
 393         printk("Starting Linux PPC64 %s\n", init_utsname()->version);
 394
 395         printk("-----------------------------------------------------\n");
 396         printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
 397         printk("physicalMemorySize            = 0x%llx\n", lmb_phys_mem_size());
 398         if (ppc64_caches.dline_size != 0x80)
 399                 printk("ppc64_caches.dcache_line_size = 0x%x\n",
 400                        ppc64_caches.dline_size);
 401         if (ppc64_caches.iline_size != 0x80)
 402                 printk("ppc64_caches.icache_line_size = 0x%x\n",
 403                        ppc64_caches.iline_size);
 404 #ifdef CONFIG_PPC_STD_MMU_64
 405         if (htab_address)
 406                 printk("htab_address                  = 0x%p\n", htab_address);
 407         printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
 408 #endif /* CONFIG_PPC_STD_MMU_64 */
 409         if (PHYSICAL_START > 0)
 410                 printk("physical_start                = 0x%llx\n",
 411                        (unsigned long long)PHYSICAL_START);
 412         printk("-----------------------------------------------------\n");
 413
 414         DBG(" <- setup_system()\n");
 415 }
 416
 417 static u64 slb0_limit(void)
 418 {
 419         if (cpu_has_feature(CPU_FTR_1T_SEGMENT)) {
 420                 return 1UL << SID_SHIFT_1T;
 421         }
 422         return 1UL << SID_SHIFT;
 423 }
 424
 425 static void __init irqstack_early_init(void)
 426 {
 427         u64 limit = slb0_limit();
 428         unsigned int i;
 429
 430         /*
 431          * interrupt stacks must be under 256MB, we cannot afford to take
 432          * SLB misses on them.
 433          */
 434         for_each_possible_cpu(i) {
 435                 softirq_ctx[i] = (struct thread_info *)
 436                         __va(lmb_alloc_base(THREAD_SIZE,
 437                                             THREAD_SIZE, limit));
 438                 hardirq_ctx[i] = (struct thread_info *)
 439                         __va(lmb_alloc_base(THREAD_SIZE,
 440                                             THREAD_SIZE, limit));
 441         }
 442 }
 443
 444 #ifdef CONFIG_PPC_BOOK3E
 445 static void __init exc_lvl_early_init(void)
 446 {
 447         unsigned int i;
 448
 449         for_each_possible_cpu(i) {
 450                 critirq_ctx[i] = (struct thread_info *)
 451                         __va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
 452                 dbgirq_ctx[i] = (struct thread_info *)
 453                         __va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
 454                 mcheckirq_ctx[i] = (struct thread_info *)
 455                         __va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
 456         }
 457 }
 458 #else
 459 #define exc_lvl_early_init()
 460 #endif
 461
 462 /*
 463  * Stack space used when we detect a bad kernel stack pointer, and
 464  * early in SMP boots before relocation is enabled.
 465  */
 466 static void __init emergency_stack_init(void)
 467 {
 468         u64 limit;
 469         unsigned int i;
 470
 471         /*
 472          * Emergency stacks must be under 256MB, we cannot afford to take
 473          * SLB misses on them. The ABI also requires them to be 128-byte
 474          * aligned.
 475          *
 476          * Since we use these as temporary stacks during secondary CPU
 477          * bringup, we need to get at them in real mode. This means they
 478          * must also be within the RMO region.
 479          */
 480         limit = min(slb0_limit(), lmb.rmo_size);
 481
 482         for_each_possible_cpu(i) {
 483                 unsigned long sp;
 484                 sp  = lmb_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
 485                 sp += THREAD_SIZE;
 486                 paca[i].emergency_sp = __va(sp);
 487         }
 488 }
 489
 490 /*
 491  * Called into from start_kernel, after lock_kernel has been called.
 492  * Initializes bootmem, which is unsed to manage page allocation until
 493  * mem_init is called.
 494  */
 495 void __init setup_arch(char **cmdline_p)
 496 {
 497         ppc64_boot_msg(0x12, "Setup Arch");
 498
 499         *cmdline_p = cmd_line;
 500
 501         /*
 502          * Set cache line size based on type of cpu as a default.
 503          * Systems with OF can look in the properties on the cpu node(s)
 504          * for a possibly more accurate value.
 505          */
 506         dcache_bsize = ppc64_caches.dline_size;
 507         icache_bsize = ppc64_caches.iline_size;
 508
 509         /* reboot on panic */
 510         panic_timeout = 180;
 511
 512         if (ppc_md.panic)
 513                 setup_panic();
 514
 515         init_mm.start_code = (unsigned long)_stext;
 516         init_mm.end_code = (unsigned long) _etext;
 517         init_mm.end_data = (unsigned long) _edata;
 518         init_mm.brk = klimit;
 519
 520         irqstack_early_init();
 521         exc_lvl_early_init();
 522         emergency_stack_init();
 523
 524 #ifdef CONFIG_PPC_STD_MMU_64
 525         stabs_alloc();
 526 #endif
 527         /* set up the bootmem stuff with available memory */
 528         do_init_bootmem();
 529         sparse_init();
 530
 531 #ifdef CONFIG_DUMMY_CONSOLE
 532         conswitchp = &dummy_con;
 533 #endif
 534
 535         if (ppc_md.setup_arch)
 536                 ppc_md.setup_arch();
 537
 538         paging_init();
 539
 540         /* Initialize the MMU context management stuff */
 541         mmu_context_init();
 542
 543         ppc64_boot_msg(0x15, "Setup Done");
 544 }
 545
 546
 547 /* ToDo: do something useful if ppc_md is not yet setup. */
 548 #define PPC64_LINUX_FUNCTION 0x0f000000
 549 #define PPC64_IPL_MESSAGE 0xc0000000
 550 #define PPC64_TERM_MESSAGE 0xb0000000
 551
 552 static void ppc64_do_msg(unsigned int src, const char *msg)
 553 {
 554         if (ppc_md.progress) {
 555                 char buf[128];
 556
 557                 sprintf(buf, "%08X\n", src);
 558                 ppc_md.progress(buf, 0);
 559                 snprintf(buf, 128, "%s", msg);
 560                 ppc_md.progress(buf, 0);
 561         }
 562 }
 563
 564 /* Print a boot progress message. */
 565 void ppc64_boot_msg(unsigned int src, const char *msg)
 566 {
 567         ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
 568         printk("[boot]%04x %s\n", src, msg);
 569 }
 570
 571 #ifdef CONFIG_SMP
 572 #define PCPU_DYN_SIZE           ()
 573
 574 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
 575 {
 576         return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
 577                                     __pa(MAX_DMA_ADDRESS));
 578 }
 579
 580 static void __init pcpu_fc_free(void *ptr, size_t size)
 581 {
 582         free_bootmem(__pa(ptr), size);
 583 }
 584
 585 static int pcpu_cpu_distance(unsigned int from, unsigned int to)
 586 {
 587         if (cpu_to_node(from) == cpu_to_node(to))
 588                 return LOCAL_DISTANCE;
 589         else
 590                 return REMOTE_DISTANCE;
 591 }
 592
 593 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
 594 EXPORT_SYMBOL(__per_cpu_offset);
 595
 596 void __init setup_per_cpu_areas(void)
 597 {
 598         const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
 599         size_t atom_size;
 600         unsigned long delta;
 601         unsigned int cpu;
 602         int rc;
 603
 604         /*
 605          * Linear mapping is one of 4K, 1M and 16M.  For 4K, no need
 606          * to group units.  For larger mappings, use 1M atom which
 607          * should be large enough to contain a number of units.
 608          */
 609         if (mmu_linear_psize == MMU_PAGE_4K)
 610                 atom_size = PAGE_SIZE;
 611         else
 612                 atom_size = 1 << 20;
 613
 614         rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
 615                                     pcpu_fc_alloc, pcpu_fc_free);
 616         if (rc < 0)
 617                 panic("cannot initialize percpu area (err=%d)", rc);
 618
 619         delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
 620         for_each_possible_cpu(cpu) {
 621                 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
 622                 paca[cpu].data_offset = __per_cpu_offset[cpu];
 623         }
 624 }
 625 #endif
 626
 627
 628 #ifdef CONFIG_PPC_INDIRECT_IO
 629 struct ppc_pci_io ppc_pci_io;
 630 EXPORT_SYMBOL(ppc_pci_io);
 631 #endif /* CONFIG_PPC_INDIRECT_IO */
 632