kernel/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/opal.h>
  36 #include <asm/kexec.h>
  37 #include <asm/smp.h>
  38
  39 #include "powernv.h"
  40
  41 static void __init pnv_setup_arch(void)
  42 {
  43         set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
  44
  45         /* Initialize SMP */
  46         pnv_smp_init();
  47
  48         /* Setup PCI */
  49         pnv_pci_init();
  50
  51         /* Setup RTC and NVRAM callbacks */
  52         if (firmware_has_feature(FW_FEATURE_OPAL))
  53                 opal_nvram_init();
  54
  55         /* Enable NAP mode */
  56         powersave_nap = 1;
  57
  58         /* XXX PMCS */
  59 }
  60
  61 static void __init pnv_init_early(void)
  62 {
  63         /*
  64          * Initialize the LPC bus now so that legacy serial
  65          * ports can be found on it
  66          */
  67         opal_lpc_init();
  68
  69 #ifdef CONFIG_HVC_OPAL
  70         if (firmware_has_feature(FW_FEATURE_OPAL))
  71                 hvc_opal_init_early();
  72         else
  73 #endif
  74                 add_preferred_console("hvc", 0, NULL);
  75 }
  76
  77 static void __init pnv_init_IRQ(void)
  78 {
  79         xics_init();
  80
  81         WARN_ON(!ppc_md.get_irq);
  82 }
  83
  84 static void pnv_show_cpuinfo(struct seq_file *m)
  85 {
  86         struct device_node *root;
  87         const char *model = "";
  88
  89         root = of_find_node_by_path("/");
  90         if (root)
  91                 model = of_get_property(root, "model", NULL);
  92         seq_printf(m, "machine\t\t: PowerNV %s\n", model);
  93         if (firmware_has_feature(FW_FEATURE_OPALv3))
  94                 seq_printf(m, "firmware\t: OPAL v3\n");
  95         else if (firmware_has_feature(FW_FEATURE_OPALv2))
  96                 seq_printf(m, "firmware\t: OPAL v2\n");
  97         else if (firmware_has_feature(FW_FEATURE_OPAL))
  98                 seq_printf(m, "firmware\t: OPAL v1\n");
  99         else
 100                 seq_printf(m, "firmware\t: BML\n");
 101         of_node_put(root);
 102 }
 103
 104 static void pnv_prepare_going_down(void)
 105 {
 106         /*
 107          * Disable all notifiers from OPAL, we can't
 108          * service interrupts anymore anyway
 109          */
 110         opal_event_shutdown();
 111
 112         /* Soft disable interrupts */
 113         local_irq_disable();
 114
 115         /*
 116          * Return secondary CPUs to firwmare if a flash update
 117          * is pending otherwise we will get all sort of error
 118          * messages about CPU being stuck etc.. This will also
 119          * have the side effect of hard disabling interrupts so
 120          * past this point, the kernel is effectively dead.
 121          */
 122         opal_flash_term_callback();
 123 }
 124
 125 static void  __noreturn pnv_restart(char *cmd)
 126 {
 127         long rc = OPAL_BUSY;
 128
 129         pnv_prepare_going_down();
 130
 131         while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
 132                 rc = opal_cec_reboot();
 133                 if (rc == OPAL_BUSY_EVENT)
 134                         opal_poll_events(NULL);
 135                 else
 136                         mdelay(10);
 137         }
 138         for (;;)
 139                 opal_poll_events(NULL);
 140 }
 141
 142 static void __noreturn pnv_power_off(void)
 143 {
 144         long rc = OPAL_BUSY;
 145
 146         pnv_prepare_going_down();
 147
 148         while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
 149                 rc = opal_cec_power_down(0);
 150                 if (rc == OPAL_BUSY_EVENT)
 151                         opal_poll_events(NULL);
 152                 else
 153                         mdelay(10);
 154         }
 155         for (;;)
 156                 opal_poll_events(NULL);
 157 }
 158
 159 static void __noreturn pnv_halt(void)
 160 {
 161         pnv_power_off();
 162 }
 163
 164 static void pnv_progress(char *s, unsigned short hex)
 165 {
 166 }
 167
 168 static void pnv_shutdown(void)
 169 {
 170         /* Let the PCI code clear up IODA tables */
 171         pnv_pci_shutdown();
 172
 173         /*
 174          * Stop OPAL activity: Unregister all OPAL interrupts so they
 175          * don't fire up while we kexec and make sure all potentially
 176          * DMA'ing ops are complete (such as dump retrieval).
 177          */
 178         opal_shutdown();
 179 }
 180
 181 #ifdef CONFIG_KEXEC
 182 static void pnv_kexec_wait_secondaries_down(void)
 183 {
 184         int my_cpu, i, notified = -1;
 185
 186         my_cpu = get_cpu();
 187
 188         for_each_online_cpu(i) {
 189                 uint8_t status;
 190                 int64_t rc, timeout = 1000;
 191
 192                 if (i == my_cpu)
 193                         continue;
 194
 195                 for (;;) {
 196                         rc = opal_query_cpu_status(get_hard_smp_processor_id(i),
 197                                                    &status);
 198                         if (rc != OPAL_SUCCESS || status != OPAL_THREAD_STARTED)
 199                                 break;
 200                         barrier();
 201                         if (i != notified) {
 202                                 printk(KERN_INFO "kexec: waiting for cpu %d "
 203                                        "(physical %d) to enter OPAL\n",
 204                                        i, paca[i].hw_cpu_id);
 205                                 notified = i;
 206                         }
 207
 208                         /*
 209                          * On crash secondaries might be unreachable or hung,
 210                          * so timeout if we've waited too long
 211                          * */
 212                         mdelay(1);
 213                         if (timeout-- == 0) {
 214                                 printk(KERN_ERR "kexec: timed out waiting for "
 215                                        "cpu %d (physical %d) to enter OPAL\n",
 216                                        i, paca[i].hw_cpu_id);
 217                                 break;
 218                         }
 219                 }
 220         }
 221 }
 222
 223 static void pnv_kexec_cpu_down(int crash_shutdown, int secondary)
 224 {
 225         xics_kexec_teardown_cpu(secondary);
 226
 227         /* On OPAL v3, we return all CPUs to firmware */
 228
 229         if (!firmware_has_feature(FW_FEATURE_OPALv3))
 230                 return;
 231
 232         if (secondary) {
 233                 /* Return secondary CPUs to firmware on OPAL v3 */
 234                 mb();
 235                 get_paca()->kexec_state = KEXEC_STATE_REAL_MODE;
 236                 mb();
 237
 238                 /* Return the CPU to OPAL */
 239                 opal_return_cpu();
 240         } else {
 241                 /* Primary waits for the secondaries to have reached OPAL */
 242                 pnv_kexec_wait_secondaries_down();
 243
 244                 /*
 245                  * We might be running as little-endian - now that interrupts
 246                  * are disabled, reset the HILE bit to big-endian so we don't
 247                  * take interrupts in the wrong endian later
 248                  */
 249                 opal_reinit_cpus(OPAL_REINIT_CPUS_HILE_BE);
 250         }
 251 }
 252 #endif /* CONFIG_KEXEC */
 253
 254 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 255 static unsigned long pnv_memory_block_size(void)
 256 {
 257         return 256UL * 1024 * 1024;
 258 }
 259 #endif
 260
 261 static void __init pnv_setup_machdep_opal(void)
 262 {
 263         ppc_md.get_boot_time = opal_get_boot_time;
 264         ppc_md.restart = pnv_restart;
 265         pm_power_off = pnv_power_off;
 266         ppc_md.halt = pnv_halt;
 267         ppc_md.machine_check_exception = opal_machine_check;
 268         ppc_md.mce_check_early_recovery = opal_mce_check_early_recovery;
 269         ppc_md.hmi_exception_early = opal_hmi_exception_early;
 270         ppc_md.handle_hmi_exception = opal_handle_hmi_exception;
 271 }
 272
 273 static int __init pnv_probe(void)
 274 {
 275         unsigned long root = of_get_flat_dt_root();
 276
 277         if (!of_flat_dt_is_compatible(root, "ibm,powernv"))
 278                 return 0;
 279
 280         hpte_init_native();
 281
 282         if (firmware_has_feature(FW_FEATURE_OPAL))
 283                 pnv_setup_machdep_opal();
 284
 285         pr_debug("PowerNV detected !\n");
 286
 287         return 1;
 288 }
 289
 290 /*
 291  * Returns the cpu frequency for 'cpu' in Hz. This is used by
 292  * /proc/cpuinfo
 293  */
 294 static unsigned long pnv_get_proc_freq(unsigned int cpu)
 295 {
 296         unsigned long ret_freq;
 297
 298         ret_freq = cpufreq_quick_get(cpu) * 1000ul;
 299
 300         /*
 301          * If the backend cpufreq driver does not exist,
 302          * then fallback to old way of reporting the clockrate.
 303          */
 304         if (!ret_freq)
 305                 ret_freq = ppc_proc_freq;
 306         return ret_freq;
 307 }
 308
 309 define_machine(powernv) {
 310         .name                   = "PowerNV",
 311         .probe                  = pnv_probe,
 312         .init_early             = pnv_init_early,
 313         .setup_arch             = pnv_setup_arch,
 314         .init_IRQ               = pnv_init_IRQ,
 315         .show_cpuinfo           = pnv_show_cpuinfo,
 316         .get_proc_freq          = pnv_get_proc_freq,
 317         .progress               = pnv_progress,
 318         .machine_shutdown       = pnv_shutdown,
 319         .power_save             = power7_idle,
 320         .calibrate_decr         = generic_calibrate_decr,
 321 #ifdef CONFIG_KEXEC
 322         .kexec_cpu_down         = pnv_kexec_cpu_down,
 323 #endif
 324 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 325         .memory_block_size      = pnv_memory_block_size,
 326 #endif
 327 };