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 <asm/io.h>
  37 #include <asm/kdump.h>
  38 #include <asm/prom.h>
  39 #include <asm/processor.h>
  40 #include <asm/pgtable.h>
  41 #include <asm/smp.h>
  42 #include <asm/elf.h>
  43 #include <asm/machdep.h>
  44 #include <asm/paca.h>
  45 #include <asm/time.h>
  46 #include <asm/cputable.h>
  47 #include <asm/sections.h>
  48 #include <asm/btext.h>
  49 #include <asm/nvram.h>
  50 #include <asm/setup.h>
  51 #include <asm/system.h>
  52 #include <asm/rtas.h>
  53 #include <asm/iommu.h>
  54 #include <asm/serial.h>
  55 #include <asm/cache.h>
  56 #include <asm/page.h>
  57 #include <asm/mmu.h>
  58 #include <asm/lmb.h>
  59 #include <asm/firmware.h>
  60 #include <asm/xmon.h>
  61 #include <asm/udbg.h>
  62 #include <asm/kexec.h>
  63
  64 #include "setup.h"
  65
  66 #ifdef DEBUG
  67 #define DBG(fmt...) udbg_printf(fmt)
  68 #else
  69 #define DBG(fmt...)
  70 #endif
  71
  72 int have_of = 1;
  73 int boot_cpuid = 0;
  74 u64 ppc64_pft_size;
  75
  76 /* Pick defaults since we might want to patch instructions
  77  * before we've read this from the device tree.
  78  */
  79 struct ppc64_caches ppc64_caches = {
  80         .dline_size = 0x40,
  81         .log_dline_size = 6,
  82         .iline_size = 0x40,
  83         .log_iline_size = 6
  84 };
  85 EXPORT_SYMBOL_GPL(ppc64_caches);
  86
  87 /*
  88  * These are used in binfmt_elf.c to put aux entries on the stack
  89  * for each elf executable being started.
  90  */
  91 int dcache_bsize;
  92 int icache_bsize;
  93 int ucache_bsize;
  94
  95 #ifdef CONFIG_SMP
  96
  97 static int smt_enabled_cmdline;
  98
  99 /* Look for ibm,smt-enabled OF option */
 100 static void check_smt_enabled(void)
 101 {
 102         struct device_node *dn;
 103         const char *smt_option;
 104
 105         /* Allow the command line to overrule the OF option */
 106         if (smt_enabled_cmdline)
 107                 return;
 108
 109         dn = of_find_node_by_path("/options");
 110
 111         if (dn) {
 112                 smt_option = of_get_property(dn, "ibm,smt-enabled", NULL);
 113
 114                 if (smt_option) {
 115                         if (!strcmp(smt_option, "on"))
 116                                 smt_enabled_at_boot = 1;
 117                         else if (!strcmp(smt_option, "off"))
 118                                 smt_enabled_at_boot = 0;
 119                 }
 120         }
 121 }
 122
 123 /* Look for smt-enabled= cmdline option */
 124 static int __init early_smt_enabled(char *p)
 125 {
 126         smt_enabled_cmdline = 1;
 127
 128         if (!p)
 129                 return 0;
 130
 131         if (!strcmp(p, "on") || !strcmp(p, "1"))
 132                 smt_enabled_at_boot = 1;
 133         else if (!strcmp(p, "off") || !strcmp(p, "0"))
 134                 smt_enabled_at_boot = 0;
 135
 136         return 0;
 137 }
 138 early_param("smt-enabled", early_smt_enabled);
 139
 140 #else
 141 #define check_smt_enabled()
 142 #endif /* CONFIG_SMP */
 143
 144 /* Put the paca pointer into r13 and SPRG3 */
 145 void __init setup_paca(int cpu)
 146 {
 147         local_paca = &paca[cpu];
 148         mtspr(SPRN_SPRG3, local_paca);
 149 }
 150
 151 /*
 152  * Early initialization entry point. This is called by head.S
 153  * with MMU translation disabled. We rely on the "feature" of
 154  * the CPU that ignores the top 2 bits of the address in real
 155  * mode so we can access kernel globals normally provided we
 156  * only toy with things in the RMO region. From here, we do
 157  * some early parsing of the device-tree to setup out LMB
 158  * data structures, and allocate & initialize the hash table
 159  * and segment tables so we can start running with translation
 160  * enabled.
 161  *
 162  * It is this function which will call the probe() callback of
 163  * the various platform types and copy the matching one to the
 164  * global ppc_md structure. Your platform can eventually do
 165  * some very early initializations from the probe() routine, but
 166  * this is not recommended, be very careful as, for example, the
 167  * device-tree is not accessible via normal means at this point.
 168  */
 169
 170 void __init early_setup(unsigned long dt_ptr)
 171 {
 172         /* Identify CPU type */
 173         identify_cpu(0, mfspr(SPRN_PVR));
 174
 175         /* Assume we're on cpu 0 for now. Don't write to the paca yet! */
 176         setup_paca(0);
 177
 178         /* Enable early debugging if any specified (see udbg.h) */
 179         udbg_early_init();
 180
 181         DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
 182
 183         /*
 184          * Do early initialization using the flattened device
 185          * tree, such as retrieving the physical memory map or
 186          * calculating/retrieving the hash table size.
 187          */
 188         early_init_devtree(__va(dt_ptr));
 189
 190         /* Now we know the logical id of our boot cpu, setup the paca. */
 191         setup_paca(boot_cpuid);
 192
 193         /* Fix up paca fields required for the boot cpu */
 194         get_paca()->cpu_start = 1;
 195         get_paca()->stab_real = __pa((u64)&initial_stab);
 196         get_paca()->stab_addr = (u64)&initial_stab;
 197
 198         /* Probe the machine type */
 199         probe_machine();
 200
 201         setup_kdump_trampoline();
 202
 203         DBG("Found, Initializing memory management...\n");
 204
 205         /*
 206          * Initialize the MMU Hash table and create the linear mapping
 207          * of memory. Has to be done before stab/slb initialization as
 208          * this is currently where the page size encoding is obtained
 209          */
 210         htab_initialize();
 211
 212         /*
 213          * Initialize stab / SLB management except on iSeries
 214          */
 215         if (cpu_has_feature(CPU_FTR_SLB))
 216                 slb_initialize();
 217         else if (!firmware_has_feature(FW_FEATURE_ISERIES))
 218                 stab_initialize(get_paca()->stab_real);
 219
 220         DBG(" <- early_setup()\n");
 221 }
 222
 223 #ifdef CONFIG_SMP
 224 void early_setup_secondary(void)
 225 {
 226         struct paca_struct *lpaca = get_paca();
 227
 228         /* Mark interrupts enabled in PACA */
 229         lpaca->soft_enabled = 0;
 230
 231         /* Initialize hash table for that CPU */
 232         htab_initialize_secondary();
 233
 234         /* Initialize STAB/SLB. We use a virtual address as it works
 235          * in real mode on pSeries and we want a virutal address on
 236          * iSeries anyway
 237          */
 238         if (cpu_has_feature(CPU_FTR_SLB))
 239                 slb_initialize();
 240         else
 241                 stab_initialize(lpaca->stab_addr);
 242 }
 243
 244 #endif /* CONFIG_SMP */
 245
 246 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
 247 void smp_release_cpus(void)
 248 {
 249         extern unsigned long __secondary_hold_spinloop;
 250         unsigned long *ptr;
 251
 252         DBG(" -> smp_release_cpus()\n");
 253
 254         /* All secondary cpus are spinning on a common spinloop, release them
 255          * all now so they can start to spin on their individual paca
 256          * spinloops. For non SMP kernels, the secondary cpus never get out
 257          * of the common spinloop.
 258          * This is useless but harmless on iSeries, secondaries are already
 259          * waiting on their paca spinloops. */
 260
 261         ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
 262                         - PHYSICAL_START);
 263         *ptr = 1;
 264         mb();
 265
 266         DBG(" <- smp_release_cpus()\n");
 267 }
 268 #endif /* CONFIG_SMP || CONFIG_KEXEC */
 269
 270 /*
 271  * Initialize some remaining members of the ppc64_caches and systemcfg
 272  * structures
 273  * (at least until we get rid of them completely). This is mostly some
 274  * cache informations about the CPU that will be used by cache flush
 275  * routines and/or provided to userland
 276  */
 277 static void __init initialize_cache_info(void)
 278 {
 279         struct device_node *np;
 280         unsigned long num_cpus = 0;
 281
 282         DBG(" -> initialize_cache_info()\n");
 283
 284         for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
 285                 num_cpus += 1;
 286
 287                 /* We're assuming *all* of the CPUs have the same
 288                  * d-cache and i-cache sizes... -Peter
 289                  */
 290
 291                 if ( num_cpus == 1 ) {
 292                         const u32 *sizep, *lsizep;
 293                         u32 size, lsize;
 294
 295                         size = 0;
 296                         lsize = cur_cpu_spec->dcache_bsize;
 297                         sizep = of_get_property(np, "d-cache-size", NULL);
 298                         if (sizep != NULL)
 299                                 size = *sizep;
 300                         lsizep = of_get_property(np, "d-cache-block-size", NULL);
 301                         /* fallback if block size missing */
 302                         if (lsizep == NULL)
 303                                 lsizep = of_get_property(np, "d-cache-line-size", NULL);
 304                         if (lsizep != NULL)
 305                                 lsize = *lsizep;
 306                         if (sizep == 0 || lsizep == 0)
 307                                 DBG("Argh, can't find dcache properties ! "
 308                                     "sizep: %p, lsizep: %p\n", sizep, lsizep);
 309
 310                         ppc64_caches.dsize = size;
 311                         ppc64_caches.dline_size = lsize;
 312                         ppc64_caches.log_dline_size = __ilog2(lsize);
 313                         ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
 314
 315                         size = 0;
 316                         lsize = cur_cpu_spec->icache_bsize;
 317                         sizep = of_get_property(np, "i-cache-size", NULL);
 318                         if (sizep != NULL)
 319                                 size = *sizep;
 320                         lsizep = of_get_property(np, "i-cache-block-size", NULL);
 321                         if (lsizep == NULL)
 322                                 lsizep = of_get_property(np, "i-cache-line-size", NULL);
 323                         if (lsizep != NULL)
 324                                 lsize = *lsizep;
 325                         if (sizep == 0 || lsizep == 0)
 326                                 DBG("Argh, can't find icache properties ! "
 327                                     "sizep: %p, lsizep: %p\n", sizep, lsizep);
 328
 329                         ppc64_caches.isize = size;
 330                         ppc64_caches.iline_size = lsize;
 331                         ppc64_caches.log_iline_size = __ilog2(lsize);
 332                         ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
 333                 }
 334         }
 335
 336         DBG(" <- initialize_cache_info()\n");
 337 }
 338
 339
 340 /*
 341  * Do some initial setup of the system.  The parameters are those which
 342  * were passed in from the bootloader.
 343  */
 344 void __init setup_system(void)
 345 {
 346         DBG(" -> setup_system()\n");
 347
 348         /* Apply the CPUs-specific and firmware specific fixups to kernel
 349          * text (nop out sections not relevant to this CPU or this firmware)
 350          */
 351         do_feature_fixups(cur_cpu_spec->cpu_features,
 352                           &__start___ftr_fixup, &__stop___ftr_fixup);
 353         do_feature_fixups(powerpc_firmware_features,
 354                           &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
 355
 356         /*
 357          * Unflatten the device-tree passed by prom_init or kexec
 358          */
 359         unflatten_device_tree();
 360
 361         /*
 362          * Fill the ppc64_caches & systemcfg structures with informations
 363          * retrieved from the device-tree.
 364          */
 365         initialize_cache_info();
 366
 367         /*
 368          * Initialize irq remapping subsystem
 369          */
 370         irq_early_init();
 371
 372 #ifdef CONFIG_PPC_RTAS
 373         /*
 374          * Initialize RTAS if available
 375          */
 376         rtas_initialize();
 377 #endif /* CONFIG_PPC_RTAS */
 378
 379         /*
 380          * Check if we have an initrd provided via the device-tree
 381          */
 382         check_for_initrd();
 383
 384         /*
 385          * Do some platform specific early initializations, that includes
 386          * setting up the hash table pointers. It also sets up some interrupt-mapping
 387          * related options that will be used by finish_device_tree()
 388          */
 389         if (ppc_md.init_early)
 390                 ppc_md.init_early();
 391
 392         /*
 393          * We can discover serial ports now since the above did setup the
 394          * hash table management for us, thus ioremap works. We do that early
 395          * so that further code can be debugged
 396          */
 397         find_legacy_serial_ports();
 398
 399         /*
 400          * Register early console
 401          */
 402         register_early_udbg_console();
 403
 404         /*
 405          * Initialize xmon
 406          */
 407         xmon_setup();
 408
 409         check_smt_enabled();
 410         smp_setup_cpu_maps();
 411
 412 #ifdef CONFIG_SMP
 413         /* Release secondary cpus out of their spinloops at 0x60 now that
 414          * we can map physical -> logical CPU ids
 415          */
 416         smp_release_cpus();
 417 #endif
 418
 419         printk("Starting Linux PPC64 %s\n", init_utsname()->version);
 420
 421         printk("-----------------------------------------------------\n");
 422         printk("ppc64_pft_size                = 0x%lx\n", ppc64_pft_size);
 423         printk("physicalMemorySize            = 0x%lx\n", lmb_phys_mem_size());
 424         if (ppc64_caches.dline_size != 0x80)
 425                 printk("ppc64_caches.dcache_line_size = 0x%x\n",
 426                        ppc64_caches.dline_size);
 427         if (ppc64_caches.iline_size != 0x80)
 428                 printk("ppc64_caches.icache_line_size = 0x%x\n",
 429                        ppc64_caches.iline_size);
 430         if (htab_address)
 431                 printk("htab_address                  = 0x%p\n", htab_address);
 432         printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
 433 #if PHYSICAL_START > 0
 434         printk("physical_start                = 0x%x\n", PHYSICAL_START);
 435 #endif
 436         printk("-----------------------------------------------------\n");
 437
 438         DBG(" <- setup_system()\n");
 439 }
 440
 441 #ifdef CONFIG_IRQSTACKS
 442 static void __init irqstack_early_init(void)
 443 {
 444         unsigned int i;
 445
 446         /*
 447          * interrupt stacks must be under 256MB, we cannot afford to take
 448          * SLB misses on them.
 449          */
 450         for_each_possible_cpu(i) {
 451                 softirq_ctx[i] = (struct thread_info *)
 452                         __va(lmb_alloc_base(THREAD_SIZE,
 453                                             THREAD_SIZE, 0x10000000));
 454                 hardirq_ctx[i] = (struct thread_info *)
 455                         __va(lmb_alloc_base(THREAD_SIZE,
 456                                             THREAD_SIZE, 0x10000000));
 457         }
 458 }
 459 #else
 460 #define irqstack_early_init()
 461 #endif
 462
 463 /*
 464  * Stack space used when we detect a bad kernel stack pointer, and
 465  * early in SMP boots before relocation is enabled.
 466  */
 467 static void __init emergency_stack_init(void)
 468 {
 469         unsigned long limit;
 470         unsigned int i;
 471
 472         /*
 473          * Emergency stacks must be under 256MB, we cannot afford to take
 474          * SLB misses on them. The ABI also requires them to be 128-byte
 475          * aligned.
 476          *
 477          * Since we use these as temporary stacks during secondary CPU
 478          * bringup, we need to get at them in real mode. This means they
 479          * must also be within the RMO region.
 480          */
 481         limit = min(0x10000000UL, lmb.rmo_size);
 482
 483         for_each_possible_cpu(i)
 484                 paca[i].emergency_sp =
 485                 __va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
 486 }
 487
 488 /*
 489  * Called into from start_kernel, after lock_kernel has been called.
 490  * Initializes bootmem, which is unsed to manage page allocation until
 491  * mem_init is called.
 492  */
 493 void __init setup_arch(char **cmdline_p)
 494 {
 495         ppc64_boot_msg(0x12, "Setup Arch");
 496
 497         *cmdline_p = cmd_line;
 498
 499         /*
 500          * Set cache line size based on type of cpu as a default.
 501          * Systems with OF can look in the properties on the cpu node(s)
 502          * for a possibly more accurate value.
 503          */
 504         dcache_bsize = ppc64_caches.dline_size;
 505         icache_bsize = ppc64_caches.iline_size;
 506
 507         /* reboot on panic */
 508         panic_timeout = 180;
 509
 510         if (ppc_md.panic)
 511                 setup_panic();
 512
 513         init_mm.start_code = PAGE_OFFSET;
 514         init_mm.end_code = (unsigned long) _etext;
 515         init_mm.end_data = (unsigned long) _edata;
 516         init_mm.brk = klimit;
 517
 518         irqstack_early_init();
 519         emergency_stack_init();
 520
 521         stabs_alloc();
 522
 523         /* set up the bootmem stuff with available memory */
 524         do_init_bootmem();
 525         sparse_init();
 526
 527 #ifdef CONFIG_DUMMY_CONSOLE
 528         conswitchp = &dummy_con;
 529 #endif
 530
 531         if (ppc_md.setup_arch)
 532                 ppc_md.setup_arch();
 533
 534         paging_init();
 535         ppc64_boot_msg(0x15, "Setup Done");
 536 }
 537
 538
 539 /* ToDo: do something useful if ppc_md is not yet setup. */
 540 #define PPC64_LINUX_FUNCTION 0x0f000000
 541 #define PPC64_IPL_MESSAGE 0xc0000000
 542 #define PPC64_TERM_MESSAGE 0xb0000000
 543
 544 static void ppc64_do_msg(unsigned int src, const char *msg)
 545 {
 546         if (ppc_md.progress) {
 547                 char buf[128];
 548
 549                 sprintf(buf, "%08X\n", src);
 550                 ppc_md.progress(buf, 0);
 551                 snprintf(buf, 128, "%s", msg);
 552                 ppc_md.progress(buf, 0);
 553         }
 554 }
 555
 556 /* Print a boot progress message. */
 557 void ppc64_boot_msg(unsigned int src, const char *msg)
 558 {
 559         ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
 560         printk("[boot]%04x %s\n", src, msg);
 561 }
 562
 563 /* Print a termination message (print only -- does not stop the kernel) */
 564 void ppc64_terminate_msg(unsigned int src, const char *msg)
 565 {
 566         ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
 567         printk("[terminate]%04x %s\n", src, msg);
 568 }
 569
 570 void cpu_die(void)
 571 {
 572         if (ppc_md.cpu_die)
 573                 ppc_md.cpu_die();
 574 }
 575
 576 #ifdef CONFIG_SMP
 577 void __init setup_per_cpu_areas(void)
 578 {
 579         int i;
 580         unsigned long size;
 581         char *ptr;
 582
 583         /* Copy section for each CPU (we discard the original) */
 584         size = ALIGN(__per_cpu_end - __per_cpu_start, PAGE_SIZE);
 585 #ifdef CONFIG_MODULES
 586         if (size < PERCPU_ENOUGH_ROOM)
 587                 size = PERCPU_ENOUGH_ROOM;
 588 #endif
 589
 590         for_each_possible_cpu(i) {
 591                 ptr = alloc_bootmem_pages_node(NODE_DATA(cpu_to_node(i)), size);
 592                 if (!ptr)
 593                         panic("Cannot allocate cpu data for CPU %d\n", i);
 594
 595                 paca[i].data_offset = ptr - __per_cpu_start;
 596                 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
 597         }
 598
 599         /* Now that per_cpu is setup, initialize cpu_sibling_map */
 600         smp_setup_cpu_sibling_map();
 601 }
 602 #endif
 603
 604
 605 #ifdef CONFIG_PPC_INDIRECT_IO
 606 struct ppc_pci_io ppc_pci_io;
 607 EXPORT_SYMBOL(ppc_pci_io);
 608 #endif /* CONFIG_PPC_INDIRECT_IO */
 609