arch/powerpc/platforms/pseries/setup.c

   1 /*
   2  *  64-bit pSeries and RS/6000 setup code.
   3  *
   4  *  Copyright (C) 1995  Linus Torvalds
   5  *  Adapted from 'alpha' version by Gary Thomas
   6  *  Modified by Cort Dougan (cort@cs.nmt.edu)
   7  *  Modified by PPC64 Team, IBM Corp
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License
  11  * as published by the Free Software Foundation; either version
  12  * 2 of the License, or (at your option) any later version.
  13  */
  14
  15 /*
  16  * bootup setup stuff..
  17  */
  18
  19 #undef DEBUG
  20
  21 #include <linux/config.h>
  22 #include <linux/cpu.h>
  23 #include <linux/errno.h>
  24 #include <linux/sched.h>
  25 #include <linux/kernel.h>
  26 #include <linux/mm.h>
  27 #include <linux/stddef.h>
  28 #include <linux/unistd.h>
  29 #include <linux/slab.h>
  30 #include <linux/user.h>
  31 #include <linux/a.out.h>
  32 #include <linux/tty.h>
  33 #include <linux/major.h>
  34 #include <linux/interrupt.h>
  35 #include <linux/reboot.h>
  36 #include <linux/init.h>
  37 #include <linux/ioport.h>
  38 #include <linux/console.h>
  39 #include <linux/pci.h>
  40 #include <linux/utsname.h>
  41 #include <linux/adb.h>
  42 #include <linux/module.h>
  43 #include <linux/delay.h>
  44 #include <linux/irq.h>
  45 #include <linux/seq_file.h>
  46 #include <linux/root_dev.h>
  47
  48 #include <asm/mmu.h>
  49 #include <asm/processor.h>
  50 #include <asm/io.h>
  51 #include <asm/pgtable.h>
  52 #include <asm/prom.h>
  53 #include <asm/rtas.h>
  54 #include <asm/pci-bridge.h>
  55 #include <asm/iommu.h>
  56 #include <asm/dma.h>
  57 #include <asm/machdep.h>
  58 #include <asm/irq.h>
  59 #include <asm/kexec.h>
  60 #include <asm/time.h>
  61 #include <asm/nvram.h>
  62 #include "xics.h"
  63 #include <asm/pmc.h>
  64 #include <asm/mpic.h>
  65 #include <asm/ppc-pci.h>
  66 #include <asm/i8259.h>
  67 #include <asm/udbg.h>
  68 #include <asm/smp.h>
  69
  70 #include "plpar_wrappers.h"
  71 #include "ras.h"
  72 #include "firmware.h"
  73
  74 #ifdef DEBUG
  75 #define DBG(fmt...) udbg_printf(fmt)
  76 #else
  77 #define DBG(fmt...)
  78 #endif
  79
  80 extern void find_udbg_vterm(void);
  81
  82 int fwnmi_active;  /* TRUE if an FWNMI handler is present */
  83
  84 static void pseries_shared_idle_sleep(void);
  85 static void pseries_dedicated_idle_sleep(void);
  86
  87 struct mpic *pSeries_mpic;
  88
  89 static void pSeries_show_cpuinfo(struct seq_file *m)
  90 {
  91         struct device_node *root;
  92         const char *model = "";
  93
  94         root = of_find_node_by_path("/");
  95         if (root)
  96                 model = get_property(root, "model", NULL);
  97         seq_printf(m, "machine\t\t: CHRP %s\n", model);
  98         of_node_put(root);
  99 }
 100
 101 /* Initialize firmware assisted non-maskable interrupts if
 102  * the firmware supports this feature.
 103  */
 104 static void __init fwnmi_init(void)
 105 {
 106         unsigned long system_reset_addr, machine_check_addr;
 107
 108         int ibm_nmi_register = rtas_token("ibm,nmi-register");
 109         if (ibm_nmi_register == RTAS_UNKNOWN_SERVICE)
 110                 return;
 111
 112         /* If the kernel's not linked at zero we point the firmware at low
 113          * addresses anyway, and use a trampoline to get to the real code. */
 114         system_reset_addr  = __pa(system_reset_fwnmi) - PHYSICAL_START;
 115         machine_check_addr = __pa(machine_check_fwnmi) - PHYSICAL_START;
 116
 117         if (0 == rtas_call(ibm_nmi_register, 2, 1, NULL, system_reset_addr,
 118                                 machine_check_addr))
 119                 fwnmi_active = 1;
 120 }
 121
 122 static void __init pSeries_init_mpic(void)
 123 {
 124         unsigned int *addrp;
 125         struct device_node *np;
 126         unsigned long intack = 0;
 127
 128         /* All ISUs are setup, complete initialization */
 129         mpic_init(pSeries_mpic);
 130
 131         /* Check what kind of cascade ACK we have */
 132         if (!(np = of_find_node_by_name(NULL, "pci"))
 133             || !(addrp = (unsigned int *)
 134                  get_property(np, "8259-interrupt-acknowledge", NULL)))
 135                 printk(KERN_ERR "Cannot find pci to get ack address\n");
 136         else
 137                 intack = addrp[prom_n_addr_cells(np)-1];
 138         of_node_put(np);
 139
 140         /* Setup the legacy interrupts & controller */
 141         i8259_init(intack, 0);
 142
 143         /* Hook cascade to mpic */
 144         mpic_setup_cascade(NUM_ISA_INTERRUPTS, i8259_irq_cascade, NULL);
 145 }
 146
 147 static void __init pSeries_setup_mpic(void)
 148 {
 149         unsigned int *opprop;
 150         unsigned long openpic_addr = 0;
 151         unsigned char senses[NR_IRQS - NUM_ISA_INTERRUPTS];
 152         struct device_node *root;
 153         int irq_count;
 154
 155         /* Find the Open PIC if present */
 156         root = of_find_node_by_path("/");
 157         opprop = (unsigned int *) get_property(root, "platform-open-pic", NULL);
 158         if (opprop != 0) {
 159                 int n = prom_n_addr_cells(root);
 160
 161                 for (openpic_addr = 0; n > 0; --n)
 162                         openpic_addr = (openpic_addr << 32) + *opprop++;
 163                 printk(KERN_DEBUG "OpenPIC addr: %lx\n", openpic_addr);
 164         }
 165         of_node_put(root);
 166
 167         BUG_ON(openpic_addr == 0);
 168
 169         /* Get the sense values from OF */
 170         prom_get_irq_senses(senses, NUM_ISA_INTERRUPTS, NR_IRQS);
 171
 172         /* Setup the openpic driver */
 173         irq_count = NR_IRQS - NUM_ISA_INTERRUPTS - 4; /* leave room for IPIs */
 174         pSeries_mpic = mpic_alloc(openpic_addr, MPIC_PRIMARY,
 175                                   16, 16, irq_count, /* isu size, irq offset, irq count */
 176                                   NR_IRQS - 4, /* ipi offset */
 177                                   senses, irq_count, /* sense & sense size */
 178                                   " MPIC     ");
 179 }
 180
 181 static void pseries_lpar_enable_pmcs(void)
 182 {
 183         unsigned long set, reset;
 184
 185         power4_enable_pmcs();
 186
 187         set = 1UL << 63;
 188         reset = 0;
 189         plpar_hcall_norets(H_PERFMON, set, reset);
 190
 191         /* instruct hypervisor to maintain PMCs */
 192         if (firmware_has_feature(FW_FEATURE_SPLPAR))
 193                 get_lppaca()->pmcregs_in_use = 1;
 194 }
 195
 196 static void __init pSeries_setup_arch(void)
 197 {
 198         /* Fixup ppc_md depending on the type of interrupt controller */
 199         if (ppc64_interrupt_controller == IC_OPEN_PIC) {
 200                 ppc_md.init_IRQ       = pSeries_init_mpic;
 201                 ppc_md.get_irq        = mpic_get_irq;
 202                 /* Allocate the mpic now, so that find_and_init_phbs() can
 203                  * fill the ISUs */
 204                 pSeries_setup_mpic();
 205         } else {
 206                 ppc_md.init_IRQ       = xics_init_IRQ;
 207                 ppc_md.get_irq        = xics_get_irq;
 208         }
 209
 210 #ifdef CONFIG_SMP
 211         smp_init_pSeries();
 212 #endif
 213         /* openpic global configuration register (64-bit format). */
 214         /* openpic Interrupt Source Unit pointer (64-bit format). */
 215         /* python0 facility area (mmio) (64-bit format) REAL address. */
 216
 217         /* init to some ~sane value until calibrate_delay() runs */
 218         loops_per_jiffy = 50000000;
 219
 220         if (ROOT_DEV == 0) {
 221                 printk("No ramdisk, default root is /dev/sda2\n");
 222                 ROOT_DEV = Root_SDA2;
 223         }
 224
 225         fwnmi_init();
 226
 227         /* Find and initialize PCI host bridges */
 228         init_pci_config_tokens();
 229         find_and_init_phbs();
 230         eeh_init();
 231
 232         pSeries_nvram_init();
 233
 234         /* Choose an idle loop */
 235         if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
 236                 vpa_init(boot_cpuid);
 237                 if (get_lppaca()->shared_proc) {
 238                         printk(KERN_DEBUG "Using shared processor idle loop\n");
 239                         ppc_md.power_save = pseries_shared_idle_sleep;
 240                 } else {
 241                         printk(KERN_DEBUG "Using dedicated idle loop\n");
 242                         ppc_md.power_save = pseries_dedicated_idle_sleep;
 243                 }
 244         } else {
 245                 printk(KERN_DEBUG "Using default idle loop\n");
 246         }
 247
 248         if (firmware_has_feature(FW_FEATURE_LPAR))
 249                 ppc_md.enable_pmcs = pseries_lpar_enable_pmcs;
 250         else
 251                 ppc_md.enable_pmcs = power4_enable_pmcs;
 252 }
 253
 254 static int __init pSeries_init_panel(void)
 255 {
 256         /* Manually leave the kernel version on the panel. */
 257         ppc_md.progress("Linux ppc64\n", 0);
 258         ppc_md.progress(system_utsname.release, 0);
 259
 260         return 0;
 261 }
 262 arch_initcall(pSeries_init_panel);
 263
 264 static  void __init pSeries_discover_pic(void)
 265 {
 266         struct device_node *np;
 267         char *typep;
 268
 269         /*
 270          * Setup interrupt mapping options that are needed for finish_device_tree
 271          * to properly parse the OF interrupt tree & do the virtual irq mapping
 272          */
 273         __irq_offset_value = NUM_ISA_INTERRUPTS;
 274         ppc64_interrupt_controller = IC_INVALID;
 275         for (np = NULL; (np = of_find_node_by_name(np, "interrupt-controller"));) {
 276                 typep = (char *)get_property(np, "compatible", NULL);
 277                 if (strstr(typep, "open-pic")) {
 278                         ppc64_interrupt_controller = IC_OPEN_PIC;
 279                         break;
 280                 } else if (strstr(typep, "ppc-xicp")) {
 281                         ppc64_interrupt_controller = IC_PPC_XIC;
 282                         break;
 283                 }
 284         }
 285         if (ppc64_interrupt_controller == IC_INVALID)
 286                 printk("pSeries_discover_pic: failed to recognize"
 287                         " interrupt-controller\n");
 288
 289 }
 290
 291 static void pSeries_mach_cpu_die(void)
 292 {
 293         local_irq_disable();
 294         idle_task_exit();
 295         /* Some hardware requires clearing the CPPR, while other hardware does not
 296          * it is safe either way
 297          */
 298         pSeriesLP_cppr_info(0, 0);
 299         rtas_stop_self();
 300         /* Should never get here... */
 301         BUG();
 302         for(;;);
 303 }
 304
 305 static int pseries_set_dabr(unsigned long dabr)
 306 {
 307         return plpar_hcall_norets(H_SET_DABR, dabr);
 308 }
 309
 310 static int pseries_set_xdabr(unsigned long dabr)
 311 {
 312         /* We want to catch accesses from kernel and userspace */
 313         return plpar_hcall_norets(H_SET_XDABR, dabr,
 314                         H_DABRX_KERNEL | H_DABRX_USER);
 315 }
 316
 317 /*
 318  * Early initialization.  Relocation is on but do not reference unbolted pages
 319  */
 320 static void __init pSeries_init_early(void)
 321 {
 322         DBG(" -> pSeries_init_early()\n");
 323
 324         fw_feature_init();
 325
 326         if (firmware_has_feature(FW_FEATURE_LPAR))
 327                 hpte_init_lpar();
 328         else
 329                 hpte_init_native();
 330
 331         if (firmware_has_feature(FW_FEATURE_LPAR))
 332                 find_udbg_vterm();
 333
 334         if (firmware_has_feature(FW_FEATURE_DABR))
 335                 ppc_md.set_dabr = pseries_set_dabr;
 336         else if (firmware_has_feature(FW_FEATURE_XDABR))
 337                 ppc_md.set_dabr = pseries_set_xdabr;
 338
 339         iommu_init_early_pSeries();
 340
 341         pSeries_discover_pic();
 342
 343         DBG(" <- pSeries_init_early()\n");
 344 }
 345
 346
 347 static int pSeries_check_legacy_ioport(unsigned int baseport)
 348 {
 349         struct device_node *np;
 350
 351 #define I8042_DATA_REG  0x60
 352 #define FDC_BASE        0x3f0
 353
 354
 355         switch(baseport) {
 356         case I8042_DATA_REG:
 357                 np = of_find_node_by_type(NULL, "8042");
 358                 if (np == NULL)
 359                         return -ENODEV;
 360                 of_node_put(np);
 361                 break;
 362         case FDC_BASE:
 363                 np = of_find_node_by_type(NULL, "fdc");
 364                 if (np == NULL)
 365                         return -ENODEV;
 366                 of_node_put(np);
 367                 break;
 368         }
 369         return 0;
 370 }
 371
 372 /*
 373  * Called very early, MMU is off, device-tree isn't unflattened
 374  */
 375
 376 static int __init pSeries_probe_hypertas(unsigned long node,
 377                                          const char *uname, int depth,
 378                                          void *data)
 379 {
 380         if (depth != 1 ||
 381             (strcmp(uname, "rtas") != 0 && strcmp(uname, "rtas@0") != 0))
 382                 return 0;
 383
 384         if (of_get_flat_dt_prop(node, "ibm,hypertas-functions", NULL) != NULL)
 385                 powerpc_firmware_features |= FW_FEATURE_LPAR;
 386
 387         return 1;
 388 }
 389
 390 static int __init pSeries_probe(void)
 391 {
 392         unsigned long root = of_get_flat_dt_root();
 393         char *dtype = of_get_flat_dt_prop(of_get_flat_dt_root(),
 394                                           "device_type", NULL);
 395         if (dtype == NULL)
 396                 return 0;
 397         if (strcmp(dtype, "chrp"))
 398                 return 0;
 399
 400         /* Cell blades firmware claims to be chrp while it's not. Until this
 401          * is fixed, we need to avoid those here.
 402          */
 403         if (of_flat_dt_is_compatible(root, "IBM,CPBW-1.0") ||
 404             of_flat_dt_is_compatible(root, "IBM,CBEA"))
 405                 return 0;
 406
 407         DBG("pSeries detected, looking for LPAR capability...\n");
 408
 409         /* Now try to figure out if we are running on LPAR */
 410         of_scan_flat_dt(pSeries_probe_hypertas, NULL);
 411
 412         DBG("Machine is%s LPAR !\n",
 413             (powerpc_firmware_features & FW_FEATURE_LPAR) ? "" : " not");
 414
 415         return 1;
 416 }
 417
 418
 419 DECLARE_PER_CPU(unsigned long, smt_snooze_delay);
 420
 421 static void pseries_dedicated_idle_sleep(void)
 422 {
 423         unsigned int cpu = smp_processor_id();
 424         unsigned long start_snooze;
 425         unsigned long *smt_snooze_delay = &__get_cpu_var(smt_snooze_delay);
 426
 427         /*
 428          * Indicate to the HV that we are idle. Now would be
 429          * a good time to find other work to dispatch.
 430          */
 431         get_lppaca()->idle = 1;
 432
 433         /*
 434          * We come in with interrupts disabled, and need_resched()
 435          * has been checked recently.  If we should poll for a little
 436          * while, do so.
 437          */
 438         if (*smt_snooze_delay) {
 439                 start_snooze = get_tb() +
 440                         *smt_snooze_delay * tb_ticks_per_usec;
 441                 local_irq_enable();
 442                 set_thread_flag(TIF_POLLING_NRFLAG);
 443
 444                 while (get_tb() < start_snooze) {
 445                         if (need_resched() || cpu_is_offline(cpu))
 446                                 goto out;
 447                         ppc64_runlatch_off();
 448                         HMT_low();
 449                         HMT_very_low();
 450                 }
 451
 452                 HMT_medium();
 453                 clear_thread_flag(TIF_POLLING_NRFLAG);
 454                 smp_mb();
 455                 local_irq_disable();
 456                 if (need_resched() || cpu_is_offline(cpu))
 457                         goto out;
 458         }
 459
 460         /*
 461          * Cede if the other thread is not idle, so that it can
 462          * go single-threaded.  If the other thread is idle,
 463          * we ask the hypervisor if it has pending work it
 464          * wants to do and cede if it does.  Otherwise we keep
 465          * polling in order to reduce interrupt latency.
 466          *
 467          * Doing the cede when the other thread is active will
 468          * result in this thread going dormant, meaning the other
 469          * thread gets to run in single-threaded (ST) mode, which
 470          * is slightly faster than SMT mode with this thread at
 471          * very low priority.  The cede enables interrupts, which
 472          * doesn't matter here.
 473          */
 474         if (!lppaca[cpu ^ 1].idle || poll_pending() == H_PENDING)
 475                 cede_processor();
 476
 477 out:
 478         HMT_medium();
 479         get_lppaca()->idle = 0;
 480 }
 481
 482 static void pseries_shared_idle_sleep(void)
 483 {
 484         /*
 485          * Indicate to the HV that we are idle. Now would be
 486          * a good time to find other work to dispatch.
 487          */
 488         get_lppaca()->idle = 1;
 489
 490         /*
 491          * Yield the processor to the hypervisor.  We return if
 492          * an external interrupt occurs (which are driven prior
 493          * to returning here) or if a prod occurs from another
 494          * processor. When returning here, external interrupts
 495          * are enabled.
 496          */
 497         cede_processor();
 498
 499         get_lppaca()->idle = 0;
 500 }
 501
 502 static int pSeries_pci_probe_mode(struct pci_bus *bus)
 503 {
 504         if (firmware_has_feature(FW_FEATURE_LPAR))
 505                 return PCI_PROBE_DEVTREE;
 506         return PCI_PROBE_NORMAL;
 507 }
 508
 509 #ifdef CONFIG_KEXEC
 510 static void pseries_kexec_cpu_down(int crash_shutdown, int secondary)
 511 {
 512         /* Don't risk a hypervisor call if we're crashing */
 513         if (firmware_has_feature(FW_FEATURE_SPLPAR) && !crash_shutdown) {
 514                 unsigned long vpa = __pa(get_lppaca());
 515
 516                 if (unregister_vpa(hard_smp_processor_id(), vpa)) {
 517                         printk("VPA deregistration of cpu %u (hw_cpu_id %d) "
 518                                         "failed\n", smp_processor_id(),
 519                                         hard_smp_processor_id());
 520                 }
 521         }
 522
 523         if (ppc64_interrupt_controller == IC_OPEN_PIC)
 524                 mpic_teardown_this_cpu(secondary);
 525         else
 526                 xics_teardown_cpu(secondary);
 527 }
 528 #endif
 529
 530 define_machine(pseries) {
 531         .name                   = "pSeries",
 532         .probe                  = pSeries_probe,
 533         .setup_arch             = pSeries_setup_arch,
 534         .init_early             = pSeries_init_early,
 535         .show_cpuinfo           = pSeries_show_cpuinfo,
 536         .log_error              = pSeries_log_error,
 537         .pcibios_fixup          = pSeries_final_fixup,
 538         .pci_probe_mode         = pSeries_pci_probe_mode,
 539         .irq_bus_setup          = pSeries_irq_bus_setup,
 540         .restart                = rtas_restart,
 541         .power_off              = rtas_power_off,
 542         .halt                   = rtas_halt,
 543         .panic                  = rtas_os_term,
 544         .cpu_die                = pSeries_mach_cpu_die,
 545         .get_boot_time          = rtas_get_boot_time,
 546         .get_rtc_time           = rtas_get_rtc_time,
 547         .set_rtc_time           = rtas_set_rtc_time,
 548         .calibrate_decr         = generic_calibrate_decr,
 549         .progress               = rtas_progress,
 550         .check_legacy_ioport    = pSeries_check_legacy_ioport,
 551         .system_reset_exception = pSeries_system_reset_exception,
 552         .machine_check_exception = pSeries_machine_check_exception,
 553 #ifdef CONFIG_KEXEC
 554         .kexec_cpu_down         = pseries_kexec_cpu_down,
 555         .machine_kexec          = default_machine_kexec,
 556         .machine_kexec_prepare  = default_machine_kexec_prepare,
 557         .machine_crash_shutdown = default_machine_crash_shutdown,
 558 #endif
 559 };