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
  65 #include "setup.h"
  66
  67 #ifdef DEBUG
  68 #define DBG(fmt...) udbg_printf(fmt)
  69 #else
  70 #define DBG(fmt...)
  71 #endif
  72
  73 int have_of = 1;
  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 /* Put the paca pointer into r13 and SPRG3 */
 146 void __init setup_paca(int cpu)
 147 {
 148         local_paca = &paca[cpu];
 149         mtspr(SPRN_SPRG3, local_paca);
 150 }
 151
 152 /*
 153  * Early initialization entry point. This is called by head.S
 154  * with MMU translation disabled. We rely on the "feature" of
 155  * the CPU that ignores the top 2 bits of the address in real
 156  * mode so we can access kernel globals normally provided we
 157  * only toy with things in the RMO region. From here, we do
 158  * some early parsing of the device-tree to setup out LMB
 159  * data structures, and allocate & initialize the hash table
 160  * and segment tables so we can start running with translation
 161  * enabled.
 162  *
 163  * It is this function which will call the probe() callback of
 164  * the various platform types and copy the matching one to the
 165  * global ppc_md structure. Your platform can eventually do
 166  * some very early initializations from the probe() routine, but
 167  * this is not recommended, be very careful as, for example, the
 168  * device-tree is not accessible via normal means at this point.
 169  */
 170
 171 void __init early_setup(unsigned long dt_ptr)
 172 {
 173         /* -------- printk is _NOT_ safe to use here ! ------- */
 174
 175         /* Fill in any unititialised pacas */
 176         initialise_pacas();
 177
 178         /* Identify CPU type */
 179         identify_cpu(0, mfspr(SPRN_PVR));
 180
 181         /* Assume we're on cpu 0 for now. Don't write to the paca yet! */
 182         setup_paca(0);
 183
 184         /* Initialize lockdep early or else spinlocks will blow */
 185         lockdep_init();
 186
 187         /* -------- printk is now safe to use ------- */
 188
 189         /* Enable early debugging if any specified (see udbg.h) */
 190         udbg_early_init();
 191
 192         DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
 193
 194         /*
 195          * Do early initialization using the flattened device
 196          * tree, such as retrieving the physical memory map or
 197          * calculating/retrieving the hash table size.
 198          */
 199         early_init_devtree(__va(dt_ptr));
 200
 201         /* Now we know the logical id of our boot cpu, setup the paca. */
 202         setup_paca(boot_cpuid);
 203
 204         /* Fix up paca fields required for the boot cpu */
 205         get_paca()->cpu_start = 1;
 206         get_paca()->stab_real = __pa((u64)&initial_stab);
 207         get_paca()->stab_addr = (u64)&initial_stab;
 208
 209         /* Probe the machine type */
 210         probe_machine();
 211
 212         setup_kdump_trampoline();
 213
 214         DBG("Found, Initializing memory management...\n");
 215
 216         /*
 217          * Initialize the MMU Hash table and create the linear mapping
 218          * of memory. Has to be done before stab/slb initialization as
 219          * this is currently where the page size encoding is obtained
 220          */
 221         htab_initialize();
 222
 223         /*
 224          * Initialize stab / SLB management except on iSeries
 225          */
 226         if (cpu_has_feature(CPU_FTR_SLB))
 227                 slb_initialize();
 228         else if (!firmware_has_feature(FW_FEATURE_ISERIES))
 229                 stab_initialize(get_paca()->stab_real);
 230
 231         DBG(" <- early_setup()\n");
 232 }
 233
 234 #ifdef CONFIG_SMP
 235 void early_setup_secondary(void)
 236 {
 237         struct paca_struct *lpaca = get_paca();
 238
 239         /* Mark interrupts enabled in PACA */
 240         lpaca->soft_enabled = 0;
 241
 242         /* Initialize hash table for that CPU */
 243         htab_initialize_secondary();
 244
 245         /* Initialize STAB/SLB. We use a virtual address as it works
 246          * in real mode on pSeries and we want a virutal address on
 247          * iSeries anyway
 248          */
 249         if (cpu_has_feature(CPU_FTR_SLB))
 250                 slb_initialize();
 251         else
 252                 stab_initialize(lpaca->stab_addr);
 253 }
 254
 255 #endif /* CONFIG_SMP */
 256
 257 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
 258 void smp_release_cpus(void)
 259 {
 260         extern unsigned long __secondary_hold_spinloop;
 261         unsigned long *ptr;
 262
 263         DBG(" -> smp_release_cpus()\n");
 264
 265         /* All secondary cpus are spinning on a common spinloop, release them
 266          * all now so they can start to spin on their individual paca
 267          * spinloops. For non SMP kernels, the secondary cpus never get out
 268          * of the common spinloop.
 269          * This is useless but harmless on iSeries, secondaries are already
 270          * waiting on their paca spinloops. */
 271
 272         ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
 273                         - PHYSICAL_START);
 274         *ptr = 1;
 275         mb();
 276
 277         DBG(" <- smp_release_cpus()\n");
 278 }
 279 #endif /* CONFIG_SMP || CONFIG_KEXEC */
 280
 281 /*
 282  * Initialize some remaining members of the ppc64_caches and systemcfg
 283  * structures
 284  * (at least until we get rid of them completely). This is mostly some
 285  * cache informations about the CPU that will be used by cache flush
 286  * routines and/or provided to userland
 287  */
 288 static void __init initialize_cache_info(void)
 289 {
 290         struct device_node *np;
 291         unsigned long num_cpus = 0;
 292
 293         DBG(" -> initialize_cache_info()\n");
 294
 295         for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
 296                 num_cpus += 1;
 297
 298                 /* We're assuming *all* of the CPUs have the same
 299                  * d-cache and i-cache sizes... -Peter
 300                  */
 301
 302                 if ( num_cpus == 1 ) {
 303                         const u32 *sizep, *lsizep;
 304                         u32 size, lsize;
 305
 306                         size = 0;
 307                         lsize = cur_cpu_spec->dcache_bsize;
 308                         sizep = of_get_property(np, "d-cache-size", NULL);
 309                         if (sizep != NULL)
 310                                 size = *sizep;
 311                         lsizep = of_get_property(np, "d-cache-block-size", NULL);
 312                         /* fallback if block size missing */
 313                         if (lsizep == NULL)
 314                                 lsizep = of_get_property(np, "d-cache-line-size", NULL);
 315                         if (lsizep != NULL)
 316                                 lsize = *lsizep;
 317                         if (sizep == 0 || lsizep == 0)
 318                                 DBG("Argh, can't find dcache properties ! "
 319                                     "sizep: %p, lsizep: %p\n", sizep, lsizep);
 320
 321                         ppc64_caches.dsize = size;
 322                         ppc64_caches.dline_size = lsize;
 323                         ppc64_caches.log_dline_size = __ilog2(lsize);
 324                         ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
 325
 326                         size = 0;
 327                         lsize = cur_cpu_spec->icache_bsize;
 328                         sizep = of_get_property(np, "i-cache-size", NULL);
 329                         if (sizep != NULL)
 330                                 size = *sizep;
 331                         lsizep = of_get_property(np, "i-cache-block-size", NULL);
 332                         if (lsizep == NULL)
 333                                 lsizep = of_get_property(np, "i-cache-line-size", NULL);
 334                         if (lsizep != NULL)
 335                                 lsize = *lsizep;
 336                         if (sizep == 0 || lsizep == 0)
 337                                 DBG("Argh, can't find icache properties ! "
 338                                     "sizep: %p, lsizep: %p\n", sizep, lsizep);
 339
 340                         ppc64_caches.isize = size;
 341                         ppc64_caches.iline_size = lsize;
 342                         ppc64_caches.log_iline_size = __ilog2(lsize);
 343                         ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
 344                 }
 345         }
 346
 347         DBG(" <- initialize_cache_info()\n");
 348 }
 349
 350
 351 /*
 352  * Do some initial setup of the system.  The parameters are those which
 353  * were passed in from the bootloader.
 354  */
 355 void __init setup_system(void)
 356 {
 357         DBG(" -> setup_system()\n");
 358
 359         /* Apply the CPUs-specific and firmware specific fixups to kernel
 360          * text (nop out sections not relevant to this CPU or this firmware)
 361          */
 362         do_feature_fixups(cur_cpu_spec->cpu_features,
 363                           &__start___ftr_fixup, &__stop___ftr_fixup);
 364         do_feature_fixups(powerpc_firmware_features,
 365                           &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
 366
 367         /*
 368          * Unflatten the device-tree passed by prom_init or kexec
 369          */
 370         unflatten_device_tree();
 371
 372         /*
 373          * Fill the ppc64_caches & systemcfg structures with informations
 374          * retrieved from the device-tree.
 375          */
 376         initialize_cache_info();
 377
 378         /*
 379          * Initialize irq remapping subsystem
 380          */
 381         irq_early_init();
 382
 383 #ifdef CONFIG_PPC_RTAS
 384         /*
 385          * Initialize RTAS if available
 386          */
 387         rtas_initialize();
 388 #endif /* CONFIG_PPC_RTAS */
 389
 390         /*
 391          * Check if we have an initrd provided via the device-tree
 392          */
 393         check_for_initrd();
 394
 395         /*
 396          * Do some platform specific early initializations, that includes
 397          * setting up the hash table pointers. It also sets up some interrupt-mapping
 398          * related options that will be used by finish_device_tree()
 399          */
 400         if (ppc_md.init_early)
 401                 ppc_md.init_early();
 402
 403         /*
 404          * We can discover serial ports now since the above did setup the
 405          * hash table management for us, thus ioremap works. We do that early
 406          * so that further code can be debugged
 407          */
 408         find_legacy_serial_ports();
 409
 410         /*
 411          * Register early console
 412          */
 413         register_early_udbg_console();
 414
 415         /*
 416          * Initialize xmon
 417          */
 418         xmon_setup();
 419
 420         check_smt_enabled();
 421         smp_setup_cpu_maps();
 422
 423 #ifdef CONFIG_SMP
 424         /* Release secondary cpus out of their spinloops at 0x60 now that
 425          * we can map physical -> logical CPU ids
 426          */
 427         smp_release_cpus();
 428 #endif
 429
 430         printk("Starting Linux PPC64 %s\n", init_utsname()->version);
 431
 432         printk("-----------------------------------------------------\n");
 433         printk("ppc64_pft_size                = 0x%lx\n", ppc64_pft_size);
 434         printk("physicalMemorySize            = 0x%lx\n", lmb_phys_mem_size());
 435         if (ppc64_caches.dline_size != 0x80)
 436                 printk("ppc64_caches.dcache_line_size = 0x%x\n",
 437                        ppc64_caches.dline_size);
 438         if (ppc64_caches.iline_size != 0x80)
 439                 printk("ppc64_caches.icache_line_size = 0x%x\n",
 440                        ppc64_caches.iline_size);
 441         if (htab_address)
 442                 printk("htab_address                  = 0x%p\n", htab_address);
 443         printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
 444 #if PHYSICAL_START > 0
 445         printk("physical_start                = 0x%lx\n", PHYSICAL_START);
 446 #endif
 447         printk("-----------------------------------------------------\n");
 448
 449         DBG(" <- setup_system()\n");
 450 }
 451
 452 #ifdef CONFIG_IRQSTACKS
 453 static void __init irqstack_early_init(void)
 454 {
 455         unsigned int i;
 456
 457         /*
 458          * interrupt stacks must be under 256MB, we cannot afford to take
 459          * SLB misses on them.
 460          */
 461         for_each_possible_cpu(i) {
 462                 softirq_ctx[i] = (struct thread_info *)
 463                         __va(lmb_alloc_base(THREAD_SIZE,
 464                                             THREAD_SIZE, 0x10000000));
 465                 hardirq_ctx[i] = (struct thread_info *)
 466                         __va(lmb_alloc_base(THREAD_SIZE,
 467                                             THREAD_SIZE, 0x10000000));
 468         }
 469 }
 470 #else
 471 #define irqstack_early_init()
 472 #endif
 473
 474 /*
 475  * Stack space used when we detect a bad kernel stack pointer, and
 476  * early in SMP boots before relocation is enabled.
 477  */
 478 static void __init emergency_stack_init(void)
 479 {
 480         unsigned long limit;
 481         unsigned int i;
 482
 483         /*
 484          * Emergency stacks must be under 256MB, we cannot afford to take
 485          * SLB misses on them. The ABI also requires them to be 128-byte
 486          * aligned.
 487          *
 488          * Since we use these as temporary stacks during secondary CPU
 489          * bringup, we need to get at them in real mode. This means they
 490          * must also be within the RMO region.
 491          */
 492         limit = min(0x10000000UL, lmb.rmo_size);
 493
 494         for_each_possible_cpu(i) {
 495                 unsigned long sp;
 496                 sp  = lmb_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
 497                 sp += THREAD_SIZE;
 498                 paca[i].emergency_sp = __va(sp);
 499         }
 500 }
 501
 502 /*
 503  * Called into from start_kernel, after lock_kernel has been called.
 504  * Initializes bootmem, which is unsed to manage page allocation until
 505  * mem_init is called.
 506  */
 507 void __init setup_arch(char **cmdline_p)
 508 {
 509         ppc64_boot_msg(0x12, "Setup Arch");
 510
 511         *cmdline_p = cmd_line;
 512
 513         /*
 514          * Set cache line size based on type of cpu as a default.
 515          * Systems with OF can look in the properties on the cpu node(s)
 516          * for a possibly more accurate value.
 517          */
 518         dcache_bsize = ppc64_caches.dline_size;
 519         icache_bsize = ppc64_caches.iline_size;
 520
 521         /* reboot on panic */
 522         panic_timeout = 180;
 523
 524         if (ppc_md.panic)
 525                 setup_panic();
 526
 527         init_mm.start_code = (unsigned long)_stext;
 528         init_mm.end_code = (unsigned long) _etext;
 529         init_mm.end_data = (unsigned long) _edata;
 530         init_mm.brk = klimit;
 531
 532         irqstack_early_init();
 533         emergency_stack_init();
 534
 535         stabs_alloc();
 536
 537         /* set up the bootmem stuff with available memory */
 538         do_init_bootmem();
 539         sparse_init();
 540
 541 #ifdef CONFIG_DUMMY_CONSOLE
 542         conswitchp = &dummy_con;
 543 #endif
 544
 545         if (ppc_md.setup_arch)
 546                 ppc_md.setup_arch();
 547
 548         paging_init();
 549         ppc64_boot_msg(0x15, "Setup Done");
 550 }
 551
 552
 553 /* ToDo: do something useful if ppc_md is not yet setup. */
 554 #define PPC64_LINUX_FUNCTION 0x0f000000
 555 #define PPC64_IPL_MESSAGE 0xc0000000
 556 #define PPC64_TERM_MESSAGE 0xb0000000
 557
 558 static void ppc64_do_msg(unsigned int src, const char *msg)
 559 {
 560         if (ppc_md.progress) {
 561                 char buf[128];
 562
 563                 sprintf(buf, "%08X\n", src);
 564                 ppc_md.progress(buf, 0);
 565                 snprintf(buf, 128, "%s", msg);
 566                 ppc_md.progress(buf, 0);
 567         }
 568 }
 569
 570 /* Print a boot progress message. */
 571 void ppc64_boot_msg(unsigned int src, const char *msg)
 572 {
 573         ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
 574         printk("[boot]%04x %s\n", src, msg);
 575 }
 576
 577 /* Print a termination message (print only -- does not stop the kernel) */
 578 void ppc64_terminate_msg(unsigned int src, const char *msg)
 579 {
 580         ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
 581         printk("[terminate]%04x %s\n", src, msg);
 582 }
 583
 584 void cpu_die(void)
 585 {
 586         if (ppc_md.cpu_die)
 587                 ppc_md.cpu_die();
 588 }
 589
 590 #ifdef CONFIG_SMP
 591 void __init setup_per_cpu_areas(void)
 592 {
 593         int i;
 594         unsigned long size;
 595         char *ptr;
 596
 597         /* Copy section for each CPU (we discard the original) */
 598         size = ALIGN(__per_cpu_end - __per_cpu_start, PAGE_SIZE);
 599 #ifdef CONFIG_MODULES
 600         if (size < PERCPU_ENOUGH_ROOM)
 601                 size = PERCPU_ENOUGH_ROOM;
 602 #endif
 603
 604         for_each_possible_cpu(i) {
 605                 ptr = alloc_bootmem_pages_node(NODE_DATA(cpu_to_node(i)), size);
 606                 if (!ptr)
 607                         panic("Cannot allocate cpu data for CPU %d\n", i);
 608
 609                 paca[i].data_offset = ptr - __per_cpu_start;
 610                 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
 611         }
 612
 613         /* Now that per_cpu is setup, initialize cpu_sibling_map */
 614         smp_setup_cpu_sibling_map();
 615 }
 616 #endif
 617
 618
 619 #ifdef CONFIG_PPC_INDIRECT_IO
 620 struct ppc_pci_io ppc_pci_io;
 621 EXPORT_SYMBOL(ppc_pci_io);
 622 #endif /* CONFIG_PPC_INDIRECT_IO */
 623