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 u64 pnv_dma_get_required_mask(struct device *dev)
 169 {
 170         if (dev_is_pci(dev))
 171                 return pnv_pci_dma_get_required_mask(to_pci_dev(dev));
 172
 173         return __dma_get_required_mask(dev);
 174 }
 175
 176 static void pnv_shutdown(void)
 177 {
 178         /* Let the PCI code clear up IODA tables */
 179         pnv_pci_shutdown();
 180
 181         /*
 182          * Stop OPAL activity: Unregister all OPAL interrupts so they
 183          * don't fire up while we kexec and make sure all potentially
 184          * DMA'ing ops are complete (such as dump retrieval).
 185          */
 186         opal_shutdown();
 187 }
 188
 189 #ifdef CONFIG_KEXEC
 190 static void pnv_kexec_wait_secondaries_down(void)
 191 {
 192         int my_cpu, i, notified = -1;
 193
 194         my_cpu = get_cpu();
 195
 196         for_each_online_cpu(i) {
 197                 uint8_t status;
 198                 int64_t rc;
 199
 200                 if (i == my_cpu)
 201                         continue;
 202
 203                 for (;;) {
 204                         rc = opal_query_cpu_status(get_hard_smp_processor_id(i),
 205                                                    &status);
 206                         if (rc != OPAL_SUCCESS || status != OPAL_THREAD_STARTED)
 207                                 break;
 208                         barrier();
 209                         if (i != notified) {
 210                                 printk(KERN_INFO "kexec: waiting for cpu %d "
 211                                        "(physical %d) to enter OPAL\n",
 212                                        i, paca[i].hw_cpu_id);
 213                                 notified = i;
 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 v3, we return all CPUs to firmware */
 224
 225         if (!firmware_has_feature(FW_FEATURE_OPALv3))
 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 if (crash_shutdown) {
 237                 /*
 238                  * On crash, we don't wait for secondaries to go
 239                  * down as they might be unreachable or hung, so
 240                  * instead we just wait a bit and move on.
 241                  */
 242                 mdelay(1);
 243         } else {
 244                 /* Primary waits for the secondaries to have reached OPAL */
 245                 pnv_kexec_wait_secondaries_down();
 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         unsigned long root = of_get_flat_dt_root();
 272
 273         if (!of_flat_dt_is_compatible(root, "ibm,powernv"))
 274                 return 0;
 275
 276         hpte_init_native();
 277
 278         if (firmware_has_feature(FW_FEATURE_OPAL))
 279                 pnv_setup_machdep_opal();
 280
 281         pr_debug("PowerNV detected !\n");
 282
 283         return 1;
 284 }
 285
 286 /*
 287  * Returns the cpu frequency for 'cpu' in Hz. This is used by
 288  * /proc/cpuinfo
 289  */
 290 static unsigned long pnv_get_proc_freq(unsigned int cpu)
 291 {
 292         unsigned long ret_freq;
 293
 294         ret_freq = cpufreq_quick_get(cpu) * 1000ul;
 295
 296         /*
 297          * If the backend cpufreq driver does not exist,
 298          * then fallback to old way of reporting the clockrate.
 299          */
 300         if (!ret_freq)
 301                 ret_freq = ppc_proc_freq;
 302         return ret_freq;
 303 }
 304
 305 define_machine(powernv) {
 306         .name                   = "PowerNV",
 307         .probe                  = pnv_probe,
 308         .init_early             = pnv_init_early,
 309         .setup_arch             = pnv_setup_arch,
 310         .init_IRQ               = pnv_init_IRQ,
 311         .show_cpuinfo           = pnv_show_cpuinfo,
 312         .get_proc_freq          = pnv_get_proc_freq,
 313         .progress               = pnv_progress,
 314         .machine_shutdown       = pnv_shutdown,
 315         .power_save             = power7_idle,
 316         .calibrate_decr         = generic_calibrate_decr,
 317         .dma_get_required_mask  = pnv_dma_get_required_mask,
 318 #ifdef CONFIG_KEXEC
 319         .kexec_cpu_down         = pnv_kexec_cpu_down,
 320 #endif
 321 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 322         .memory_block_size      = pnv_memory_block_size,
 323 #endif
 324 };