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/xive.h>
  36 #include <asm/opal.h>
  37 #include <asm/kexec.h>
  38 #include <asm/smp.h>
  39
  40 #include "powernv.h"
  41
  42 static void __init pnv_setup_arch(void)
  43 {
  44         set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
  45
  46         /* Initialize SMP */
  47         pnv_smp_init();
  48
  49         /* Setup PCI */
  50         pnv_pci_init();
  51
  52         /* Setup RTC and NVRAM callbacks */
  53         if (firmware_has_feature(FW_FEATURE_OPAL))
  54                 opal_nvram_init();
  55
  56         /* Enable NAP mode */
  57         powersave_nap = 1;
  58
  59         /* XXX PMCS */
  60 }
  61
  62 static void __init pnv_init(void)
  63 {
  64         /*
  65          * Initialize the LPC bus now so that legacy serial
  66          * ports can be found on it
  67          */
  68         opal_lpc_init();
  69
  70 #ifdef CONFIG_HVC_OPAL
  71         if (firmware_has_feature(FW_FEATURE_OPAL))
  72                 hvc_opal_init_early();
  73         else
  74 #endif
  75                 add_preferred_console("hvc", 0, NULL);
  76 }
  77
  78 static void __init pnv_init_IRQ(void)
  79 {
  80         /* Try using a XIVE if available, otherwise use a XICS */
  81         if (!xive_native_init())
  82                 xics_init();
  83
  84         WARN_ON(!ppc_md.get_irq);
  85 }
  86
  87 static void pnv_show_cpuinfo(struct seq_file *m)
  88 {
  89         struct device_node *root;
  90         const char *model = "";
  91
  92         root = of_find_node_by_path("/");
  93         if (root)
  94                 model = of_get_property(root, "model", NULL);
  95         seq_printf(m, "machine\t\t: PowerNV %s\n", model);
  96         if (firmware_has_feature(FW_FEATURE_OPAL))
  97                 seq_printf(m, "firmware\t: OPAL\n");
  98         else
  99                 seq_printf(m, "firmware\t: BML\n");
 100         of_node_put(root);
 101 }
 102
 103 static void pnv_prepare_going_down(void)
 104 {
 105         /*
 106          * Disable all notifiers from OPAL, we can't
 107          * service interrupts anymore anyway
 108          */
 109         opal_event_shutdown();
 110
 111         /* Soft disable interrupts */
 112         local_irq_disable();
 113
 114         /*
 115          * Return secondary CPUs to firwmare if a flash update
 116          * is pending otherwise we will get all sort of error
 117          * messages about CPU being stuck etc.. This will also
 118          * have the side effect of hard disabling interrupts so
 119          * past this point, the kernel is effectively dead.
 120          */
 121         opal_flash_term_callback();
 122 }
 123
 124 static void  __noreturn pnv_restart(char *cmd)
 125 {
 126         long rc = OPAL_BUSY;
 127
 128         pnv_prepare_going_down();
 129
 130         while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
 131                 rc = opal_cec_reboot();
 132                 if (rc == OPAL_BUSY_EVENT)
 133                         opal_poll_events(NULL);
 134                 else
 135                         mdelay(10);
 136         }
 137         for (;;)
 138                 opal_poll_events(NULL);
 139 }
 140
 141 static void __noreturn pnv_power_off(void)
 142 {
 143         long rc = OPAL_BUSY;
 144
 145         pnv_prepare_going_down();
 146
 147         while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
 148                 rc = opal_cec_power_down(0);
 149                 if (rc == OPAL_BUSY_EVENT)
 150                         opal_poll_events(NULL);
 151                 else
 152                         mdelay(10);
 153         }
 154         for (;;)
 155                 opal_poll_events(NULL);
 156 }
 157
 158 static void __noreturn pnv_halt(void)
 159 {
 160         pnv_power_off();
 161 }
 162
 163 static void pnv_progress(char *s, unsigned short hex)
 164 {
 165 }
 166
 167 static void pnv_shutdown(void)
 168 {
 169         /* Let the PCI code clear up IODA tables */
 170         pnv_pci_shutdown();
 171
 172         /*
 173          * Stop OPAL activity: Unregister all OPAL interrupts so they
 174          * don't fire up while we kexec and make sure all potentially
 175          * DMA'ing ops are complete (such as dump retrieval).
 176          */
 177         opal_shutdown();
 178 }
 179
 180 #ifdef CONFIG_KEXEC_CORE
 181 static void pnv_kexec_wait_secondaries_down(void)
 182 {
 183         int my_cpu, i, notified = -1;
 184
 185         my_cpu = get_cpu();
 186
 187         for_each_online_cpu(i) {
 188                 uint8_t status;
 189                 int64_t rc, timeout = 1000;
 190
 191                 if (i == my_cpu)
 192                         continue;
 193
 194                 for (;;) {
 195                         rc = opal_query_cpu_status(get_hard_smp_processor_id(i),
 196                                                    &status);
 197                         if (rc != OPAL_SUCCESS || status != OPAL_THREAD_STARTED)
 198                                 break;
 199                         barrier();
 200                         if (i != notified) {
 201                                 printk(KERN_INFO "kexec: waiting for cpu %d "
 202                                        "(physical %d) to enter OPAL\n",
 203                                        i, paca[i].hw_cpu_id);
 204                                 notified = i;
 205                         }
 206
 207                         /*
 208                          * On crash secondaries might be unreachable or hung,
 209                          * so timeout if we've waited too long
 210                          * */
 211                         mdelay(1);
 212                         if (timeout-- == 0) {
 213                                 printk(KERN_ERR "kexec: timed out waiting for "
 214                                        "cpu %d (physical %d) to enter OPAL\n",
 215                                        i, paca[i].hw_cpu_id);
 216                                 break;
 217                         }
 218                 }
 219         }
 220 }
 221
 222 static void pnv_kexec_cpu_down(int crash_shutdown, int secondary)
 223 {
 224         if (xive_enabled())
 225                 xive_kexec_teardown_cpu(secondary);
 226         else
 227                 xics_kexec_teardown_cpu(secondary);
 228
 229         /* On OPAL, we return all CPUs to firmware */
 230         if (!firmware_has_feature(FW_FEATURE_OPAL))
 231                 return;
 232
 233         if (secondary) {
 234                 /* Return secondary CPUs to firmware on OPAL v3 */
 235                 mb();
 236                 get_paca()->kexec_state = KEXEC_STATE_REAL_MODE;
 237                 mb();
 238
 239                 /* Return the CPU to OPAL */
 240                 opal_return_cpu();
 241         } else {
 242                 /* Primary waits for the secondaries to have reached OPAL */
 243                 pnv_kexec_wait_secondaries_down();
 244
 245                 /* Switch XIVE back to emulation mode */
 246                 if (xive_enabled())
 247                         xive_shutdown();
 248
 249                 /*
 250                  * We might be running as little-endian - now that interrupts
 251                  * are disabled, reset the HILE bit to big-endian so we don't
 252                  * take interrupts in the wrong endian later
 253                  */
 254                 opal_reinit_cpus(OPAL_REINIT_CPUS_HILE_BE);
 255         }
 256 }
 257 #endif /* CONFIG_KEXEC_CORE */
 258
 259 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 260 static unsigned long pnv_memory_block_size(void)
 261 {
 262         return 256UL * 1024 * 1024;
 263 }
 264 #endif
 265
 266 static void __init pnv_setup_machdep_opal(void)
 267 {
 268         ppc_md.get_boot_time = opal_get_boot_time;
 269         ppc_md.restart = pnv_restart;
 270         pm_power_off = pnv_power_off;
 271         ppc_md.halt = pnv_halt;
 272         ppc_md.machine_check_exception = opal_machine_check;
 273         ppc_md.mce_check_early_recovery = opal_mce_check_early_recovery;
 274         ppc_md.hmi_exception_early = opal_hmi_exception_early;
 275         ppc_md.handle_hmi_exception = opal_handle_hmi_exception;
 276 }
 277
 278 static int __init pnv_probe(void)
 279 {
 280         if (!of_machine_is_compatible("ibm,powernv"))
 281                 return 0;
 282
 283         if (firmware_has_feature(FW_FEATURE_OPAL))
 284                 pnv_setup_machdep_opal();
 285
 286         pr_debug("PowerNV detected !\n");
 287
 288         pnv_init();
 289
 290         return 1;
 291 }
 292
 293 /*
 294  * Returns the cpu frequency for 'cpu' in Hz. This is used by
 295  * /proc/cpuinfo
 296  */
 297 static unsigned long pnv_get_proc_freq(unsigned int cpu)
 298 {
 299         unsigned long ret_freq;
 300
 301         ret_freq = cpufreq_quick_get(cpu) * 1000ul;
 302
 303         /*
 304          * If the backend cpufreq driver does not exist,
 305          * then fallback to old way of reporting the clockrate.
 306          */
 307         if (!ret_freq)
 308                 ret_freq = ppc_proc_freq;
 309         return ret_freq;
 310 }
 311
 312 define_machine(powernv) {
 313         .name                   = "PowerNV",
 314         .probe                  = pnv_probe,
 315         .setup_arch             = pnv_setup_arch,
 316         .init_IRQ               = pnv_init_IRQ,
 317         .show_cpuinfo           = pnv_show_cpuinfo,
 318         .get_proc_freq          = pnv_get_proc_freq,
 319         .progress               = pnv_progress,
 320         .machine_shutdown       = pnv_shutdown,
 321         .power_save             = NULL,
 322         .calibrate_decr         = generic_calibrate_decr,
 323 #ifdef CONFIG_KEXEC_CORE
 324         .kexec_cpu_down         = pnv_kexec_cpu_down,
 325 #endif
 326 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 327         .memory_block_size      = pnv_memory_block_size,
 328 #endif
 329 };