arch/powerpc/platforms/powernv/setup.c

   1 /*
   2  * PowerNV setup code.
   3  *
   4  * Copyright 2011 IBM Corp.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #undef DEBUG
  13
  14 #include <linux/cpu.h>
  15 #include <linux/errno.h>
  16 #include <linux/sched.h>
  17 #include <linux/kernel.h>
  18 #include <linux/tty.h>
  19 #include <linux/reboot.h>
  20 #include <linux/init.h>
  21 #include <linux/console.h>
  22 #include <linux/delay.h>
  23 #include <linux/irq.h>
  24 #include <linux/seq_file.h>
  25 #include <linux/of.h>
  26 #include <linux/of_fdt.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/bug.h>
  29 #include <linux/pci.h>
  30 #include <linux/cpufreq.h>
  31
  32 #include <asm/machdep.h>
  33 #include <asm/firmware.h>
  34 #include <asm/xics.h>
  35 #include <asm/rtas.h>
  36 #include <asm/opal.h>
  37 #include <asm/kexec.h>
  38 #include <asm/smp.h>
  39 #include <asm/cputhreads.h>
  40 #include <asm/cpuidle.h>
  41 #include <asm/code-patching.h>
  42
  43 #include "powernv.h"
  44 #include "subcore.h"
  45
  46 static void __init pnv_setup_arch(void)
  47 {
  48         set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
  49
  50         /* Initialize SMP */
  51         pnv_smp_init();
  52
  53         /* Setup PCI */
  54         pnv_pci_init();
  55
  56         /* Setup RTC and NVRAM callbacks */
  57         if (firmware_has_feature(FW_FEATURE_OPAL))
  58                 opal_nvram_init();
  59
  60         /* Enable NAP mode */
  61         powersave_nap = 1;
  62
  63         /* XXX PMCS */
  64 }
  65
  66 static void __init pnv_init_early(void)
  67 {
  68         /*
  69          * Initialize the LPC bus now so that legacy serial
  70          * ports can be found on it
  71          */
  72         opal_lpc_init();
  73
  74 #ifdef CONFIG_HVC_OPAL
  75         if (firmware_has_feature(FW_FEATURE_OPAL))
  76                 hvc_opal_init_early();
  77         else
  78 #endif
  79                 add_preferred_console("hvc", 0, NULL);
  80 }
  81
  82 static void __init pnv_init_IRQ(void)
  83 {
  84         xics_init();
  85
  86         WARN_ON(!ppc_md.get_irq);
  87 }
  88
  89 static void pnv_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 = of_get_property(root, "model", NULL);
  97         seq_printf(m, "machine\t\t: PowerNV %s\n", model);
  98         if (firmware_has_feature(FW_FEATURE_OPALv3))
  99                 seq_printf(m, "firmware\t: OPAL v3\n");
 100         else if (firmware_has_feature(FW_FEATURE_OPALv2))
 101                 seq_printf(m, "firmware\t: OPAL v2\n");
 102         else if (firmware_has_feature(FW_FEATURE_OPAL))
 103                 seq_printf(m, "firmware\t: OPAL v1\n");
 104         else
 105                 seq_printf(m, "firmware\t: BML\n");
 106         of_node_put(root);
 107 }
 108
 109 static void pnv_prepare_going_down(void)
 110 {
 111         /*
 112          * Disable all notifiers from OPAL, we can't
 113          * service interrupts anymore anyway
 114          */
 115         opal_notifier_disable();
 116
 117         /* Soft disable interrupts */
 118         local_irq_disable();
 119
 120         /*
 121          * Return secondary CPUs to firwmare if a flash update
 122          * is pending otherwise we will get all sort of error
 123          * messages about CPU being stuck etc.. This will also
 124          * have the side effect of hard disabling interrupts so
 125          * past this point, the kernel is effectively dead.
 126          */
 127         opal_flash_term_callback();
 128 }
 129
 130 static void  __noreturn pnv_restart(char *cmd)
 131 {
 132         long rc = OPAL_BUSY;
 133
 134         pnv_prepare_going_down();
 135
 136         while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
 137                 rc = opal_cec_reboot();
 138                 if (rc == OPAL_BUSY_EVENT)
 139                         opal_poll_events(NULL);
 140                 else
 141                         mdelay(10);
 142         }
 143         for (;;)
 144                 opal_poll_events(NULL);
 145 }
 146
 147 static void __noreturn pnv_power_off(void)
 148 {
 149         long rc = OPAL_BUSY;
 150
 151         pnv_prepare_going_down();
 152
 153         while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
 154                 rc = opal_cec_power_down(0);
 155                 if (rc == OPAL_BUSY_EVENT)
 156                         opal_poll_events(NULL);
 157                 else
 158                         mdelay(10);
 159         }
 160         for (;;)
 161                 opal_poll_events(NULL);
 162 }
 163
 164 static void __noreturn pnv_halt(void)
 165 {
 166         pnv_power_off();
 167 }
 168
 169 static void pnv_progress(char *s, unsigned short hex)
 170 {
 171 }
 172
 173 static int pnv_dma_set_mask(struct device *dev, u64 dma_mask)
 174 {
 175         if (dev_is_pci(dev))
 176                 return pnv_pci_dma_set_mask(to_pci_dev(dev), dma_mask);
 177         return __dma_set_mask(dev, dma_mask);
 178 }
 179
 180 static u64 pnv_dma_get_required_mask(struct device *dev)
 181 {
 182         if (dev_is_pci(dev))
 183                 return pnv_pci_dma_get_required_mask(to_pci_dev(dev));
 184
 185         return __dma_get_required_mask(dev);
 186 }
 187
 188 static void pnv_shutdown(void)
 189 {
 190         /* Let the PCI code clear up IODA tables */
 191         pnv_pci_shutdown();
 192
 193         /*
 194          * Stop OPAL activity: Unregister all OPAL interrupts so they
 195          * don't fire up while we kexec and make sure all potentially
 196          * DMA'ing ops are complete (such as dump retrieval).
 197          */
 198         opal_shutdown();
 199 }
 200
 201 #ifdef CONFIG_KEXEC
 202 static void pnv_kexec_wait_secondaries_down(void)
 203 {
 204         int my_cpu, i, notified = -1;
 205
 206         my_cpu = get_cpu();
 207
 208         for_each_online_cpu(i) {
 209                 uint8_t status;
 210                 int64_t rc;
 211
 212                 if (i == my_cpu)
 213                         continue;
 214
 215                 for (;;) {
 216                         rc = opal_query_cpu_status(get_hard_smp_processor_id(i),
 217                                                    &status);
 218                         if (rc != OPAL_SUCCESS || status != OPAL_THREAD_STARTED)
 219                                 break;
 220                         barrier();
 221                         if (i != notified) {
 222                                 printk(KERN_INFO "kexec: waiting for cpu %d "
 223                                        "(physical %d) to enter OPAL\n",
 224                                        i, paca[i].hw_cpu_id);
 225                                 notified = i;
 226                         }
 227                 }
 228         }
 229 }
 230
 231 static void pnv_kexec_cpu_down(int crash_shutdown, int secondary)
 232 {
 233         xics_kexec_teardown_cpu(secondary);
 234
 235         /* On OPAL v3, we return all CPUs to firmware */
 236
 237         if (!firmware_has_feature(FW_FEATURE_OPALv3))
 238                 return;
 239
 240         if (secondary) {
 241                 /* Return secondary CPUs to firmware on OPAL v3 */
 242                 mb();
 243                 get_paca()->kexec_state = KEXEC_STATE_REAL_MODE;
 244                 mb();
 245
 246                 /* Return the CPU to OPAL */
 247                 opal_return_cpu();
 248         } else if (crash_shutdown) {
 249                 /*
 250                  * On crash, we don't wait for secondaries to go
 251                  * down as they might be unreachable or hung, so
 252                  * instead we just wait a bit and move on.
 253                  */
 254                 mdelay(1);
 255         } else {
 256                 /* Primary waits for the secondaries to have reached OPAL */
 257                 pnv_kexec_wait_secondaries_down();
 258         }
 259 }
 260 #endif /* CONFIG_KEXEC */
 261
 262 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 263 static unsigned long pnv_memory_block_size(void)
 264 {
 265         return 256UL * 1024 * 1024;
 266 }
 267 #endif
 268
 269 static void __init pnv_setup_machdep_opal(void)
 270 {
 271         ppc_md.get_boot_time = opal_get_boot_time;
 272         ppc_md.restart = pnv_restart;
 273         pm_power_off = pnv_power_off;
 274         ppc_md.halt = pnv_halt;
 275         ppc_md.machine_check_exception = opal_machine_check;
 276         ppc_md.mce_check_early_recovery = opal_mce_check_early_recovery;
 277         ppc_md.hmi_exception_early = opal_hmi_exception_early;
 278         ppc_md.handle_hmi_exception = opal_handle_hmi_exception;
 279 }
 280
 281 #ifdef CONFIG_PPC_POWERNV_RTAS
 282 static void __init pnv_setup_machdep_rtas(void)
 283 {
 284         if (rtas_token("get-time-of-day") != RTAS_UNKNOWN_SERVICE) {
 285                 ppc_md.get_boot_time = rtas_get_boot_time;
 286                 ppc_md.get_rtc_time = rtas_get_rtc_time;
 287                 ppc_md.set_rtc_time = rtas_set_rtc_time;
 288         }
 289         ppc_md.restart = rtas_restart;
 290         pm_power_off = rtas_power_off;
 291         ppc_md.halt = rtas_halt;
 292 }
 293 #endif /* CONFIG_PPC_POWERNV_RTAS */
 294
 295 static u32 supported_cpuidle_states;
 296
 297 int pnv_save_sprs_for_winkle(void)
 298 {
 299         int cpu;
 300         int rc;
 301
 302         /*
 303          * hid0, hid1, hid4, hid5, hmeer and lpcr values are symmetric accross
 304          * all cpus at boot. Get these reg values of current cpu and use the
 305          * same accross all cpus.
 306          */
 307         uint64_t lpcr_val = mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1;
 308         uint64_t hid0_val = mfspr(SPRN_HID0);
 309         uint64_t hid1_val = mfspr(SPRN_HID1);
 310         uint64_t hid4_val = mfspr(SPRN_HID4);
 311         uint64_t hid5_val = mfspr(SPRN_HID5);
 312         uint64_t hmeer_val = mfspr(SPRN_HMEER);
 313
 314         for_each_possible_cpu(cpu) {
 315                 uint64_t pir = get_hard_smp_processor_id(cpu);
 316                 uint64_t hsprg0_val = (uint64_t)&paca[cpu];
 317
 318                 /*
 319                  * HSPRG0 is used to store the cpu's pointer to paca. Hence last
 320                  * 3 bits are guaranteed to be 0. Program slw to restore HSPRG0
 321                  * with 63rd bit set, so that when a thread wakes up at 0x100 we
 322                  * can use this bit to distinguish between fastsleep and
 323                  * deep winkle.
 324                  */
 325                 hsprg0_val |= 1;
 326
 327                 rc = opal_slw_set_reg(pir, SPRN_HSPRG0, hsprg0_val);
 328                 if (rc != 0)
 329                         return rc;
 330
 331                 rc = opal_slw_set_reg(pir, SPRN_LPCR, lpcr_val);
 332                 if (rc != 0)
 333                         return rc;
 334
 335                 /* HIDs are per core registers */
 336                 if (cpu_thread_in_core(cpu) == 0) {
 337
 338                         rc = opal_slw_set_reg(pir, SPRN_HMEER, hmeer_val);
 339                         if (rc != 0)
 340                                 return rc;
 341
 342                         rc = opal_slw_set_reg(pir, SPRN_HID0, hid0_val);
 343                         if (rc != 0)
 344                                 return rc;
 345
 346                         rc = opal_slw_set_reg(pir, SPRN_HID1, hid1_val);
 347                         if (rc != 0)
 348                                 return rc;
 349
 350                         rc = opal_slw_set_reg(pir, SPRN_HID4, hid4_val);
 351                         if (rc != 0)
 352                                 return rc;
 353
 354                         rc = opal_slw_set_reg(pir, SPRN_HID5, hid5_val);
 355                         if (rc != 0)
 356                                 return rc;
 357                 }
 358         }
 359
 360         return 0;
 361 }
 362
 363 static void pnv_alloc_idle_core_states(void)
 364 {
 365         int i, j;
 366         int nr_cores = cpu_nr_cores();
 367         u32 *core_idle_state;
 368
 369         /*
 370          * core_idle_state - First 8 bits track the idle state of each thread
 371          * of the core. The 8th bit is the lock bit. Initially all thread bits
 372          * are set. They are cleared when the thread enters deep idle state
 373          * like sleep and winkle. Initially the lock bit is cleared.
 374          * The lock bit has 2 purposes
 375          * a. While the first thread is restoring core state, it prevents
 376          * other threads in the core from switching to process context.
 377          * b. While the last thread in the core is saving the core state, it
 378          * prevents a different thread from waking up.
 379          */
 380         for (i = 0; i < nr_cores; i++) {
 381                 int first_cpu = i * threads_per_core;
 382                 int node = cpu_to_node(first_cpu);
 383
 384                 core_idle_state = kmalloc_node(sizeof(u32), GFP_KERNEL, node);
 385                 *core_idle_state = PNV_CORE_IDLE_THREAD_BITS;
 386
 387                 for (j = 0; j < threads_per_core; j++) {
 388                         int cpu = first_cpu + j;
 389
 390                         paca[cpu].core_idle_state_ptr = core_idle_state;
 391                         paca[cpu].thread_idle_state = PNV_THREAD_RUNNING;
 392                         paca[cpu].thread_mask = 1 << j;
 393                 }
 394         }
 395
 396         update_subcore_sibling_mask();
 397
 398         if (supported_cpuidle_states & OPAL_PM_WINKLE_ENABLED)
 399                 pnv_save_sprs_for_winkle();
 400 }
 401
 402 u32 pnv_get_supported_cpuidle_states(void)
 403 {
 404         return supported_cpuidle_states;
 405 }
 406 EXPORT_SYMBOL_GPL(pnv_get_supported_cpuidle_states);
 407
 408 static int __init pnv_init_idle_states(void)
 409 {
 410         struct device_node *power_mgt;
 411         int dt_idle_states;
 412         const __be32 *idle_state_flags;
 413         u32 len_flags, flags;
 414         int i;
 415
 416         supported_cpuidle_states = 0;
 417
 418         if (cpuidle_disable != IDLE_NO_OVERRIDE)
 419                 return 0;
 420
 421         if (!firmware_has_feature(FW_FEATURE_OPALv3))
 422                 return 0;
 423
 424         power_mgt = of_find_node_by_path("/ibm,opal/power-mgt");
 425         if (!power_mgt) {
 426                 pr_warn("opal: PowerMgmt Node not found\n");
 427                 return 0;
 428         }
 429
 430         idle_state_flags = of_get_property(power_mgt,
 431                         "ibm,cpu-idle-state-flags", &len_flags);
 432         if (!idle_state_flags) {
 433                 pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-flags\n");
 434                 return 0;
 435         }
 436
 437         dt_idle_states = len_flags / sizeof(u32);
 438
 439         for (i = 0; i < dt_idle_states; i++) {
 440                 flags = be32_to_cpu(idle_state_flags[i]);
 441                 supported_cpuidle_states |= flags;
 442         }
 443         if (!(supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED_ER1)) {
 444                 patch_instruction(
 445                         (unsigned int *)pnv_fastsleep_workaround_at_entry,
 446                         PPC_INST_NOP);
 447                 patch_instruction(
 448                         (unsigned int *)pnv_fastsleep_workaround_at_exit,
 449                         PPC_INST_NOP);
 450         }
 451         pnv_alloc_idle_core_states();
 452         return 0;
 453 }
 454
 455 subsys_initcall(pnv_init_idle_states);
 456
 457 static int __init pnv_probe(void)
 458 {
 459         unsigned long root = of_get_flat_dt_root();
 460
 461         if (!of_flat_dt_is_compatible(root, "ibm,powernv"))
 462                 return 0;
 463
 464         hpte_init_native();
 465
 466         if (firmware_has_feature(FW_FEATURE_OPAL))
 467                 pnv_setup_machdep_opal();
 468 #ifdef CONFIG_PPC_POWERNV_RTAS
 469         else if (rtas.base)
 470                 pnv_setup_machdep_rtas();
 471 #endif /* CONFIG_PPC_POWERNV_RTAS */
 472
 473         pr_debug("PowerNV detected !\n");
 474
 475         return 1;
 476 }
 477
 478 /*
 479  * Returns the cpu frequency for 'cpu' in Hz. This is used by
 480  * /proc/cpuinfo
 481  */
 482 static unsigned long pnv_get_proc_freq(unsigned int cpu)
 483 {
 484         unsigned long ret_freq;
 485
 486         ret_freq = cpufreq_quick_get(cpu) * 1000ul;
 487
 488         /*
 489          * If the backend cpufreq driver does not exist,
 490          * then fallback to old way of reporting the clockrate.
 491          */
 492         if (!ret_freq)
 493                 ret_freq = ppc_proc_freq;
 494         return ret_freq;
 495 }
 496
 497 define_machine(powernv) {
 498         .name                   = "PowerNV",
 499         .probe                  = pnv_probe,
 500         .init_early             = pnv_init_early,
 501         .setup_arch             = pnv_setup_arch,
 502         .init_IRQ               = pnv_init_IRQ,
 503         .show_cpuinfo           = pnv_show_cpuinfo,
 504         .get_proc_freq          = pnv_get_proc_freq,
 505         .progress               = pnv_progress,
 506         .machine_shutdown       = pnv_shutdown,
 507         .power_save             = power7_idle,
 508         .calibrate_decr         = generic_calibrate_decr,
 509         .dma_set_mask           = pnv_dma_set_mask,
 510         .dma_get_required_mask  = pnv_dma_get_required_mask,
 511 #ifdef CONFIG_KEXEC
 512         .kexec_cpu_down         = pnv_kexec_cpu_down,
 513 #endif
 514 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 515         .memory_block_size      = pnv_memory_block_size,
 516 #endif
 517 };