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