LXR linux/arch/powerpc/kernel/machine

   1/*
   2 * Code to handle transition of Linux booting another kernel.
   3 *
   4 * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
   5 * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
   6 * Copyright (C) 2005 IBM Corporation.
   7 *
   8 * This source code is licensed under the GNU General Public License,
   9 * Version 2.  See the file COPYING for more details.
  10 */
  11
  12#include <linux/kexec.h>
  13#include <linux/reboot.h>
  14#include <linux/threads.h>
  15#include <linux/memblock.h>
  16#include <linux/of.h>
  17#include <linux/irq.h>
  18#include <linux/ftrace.h>
  19
  20#include <asm/machdep.h>
  21#include <asm/pgalloc.h>
  22#include <asm/prom.h>
  23#include <asm/sections.h>
  24
  25void machine_kexec_mask_interrupts(void) {
  26        unsigned int i;
  27        struct irq_desc *desc;
  28
  29        for_each_irq_desc(i, desc) {
  30                struct irq_chip *chip;
  31
  32                chip = irq_desc_get_chip(desc);
  33                if (!chip)
  34                        continue;
  35
  36                if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
  37                        chip->irq_eoi(&desc->irq_data);
  38
  39                if (chip->irq_mask)
  40                        chip->irq_mask(&desc->irq_data);
  41
  42                if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
  43                        chip->irq_disable(&desc->irq_data);
  44        }
  45}
  46
  47void machine_crash_shutdown(struct pt_regs *regs)
  48{
  49        default_machine_crash_shutdown(regs);
  50}
  51
  52/*
  53 * Do what every setup is needed on image and the
  54 * reboot code buffer to allow us to avoid allocations
  55 * later.
  56 */
  57int machine_kexec_prepare(struct kimage *image)
  58{
  59        if (ppc_md.machine_kexec_prepare)
  60                return ppc_md.machine_kexec_prepare(image);
  61        else
  62                return default_machine_kexec_prepare(image);
  63}
  64
  65void machine_kexec_cleanup(struct kimage *image)
  66{
  67}
  68
  69void arch_crash_save_vmcoreinfo(void)
  70{
  71
  72#ifdef CONFIG_NEED_MULTIPLE_NODES
  73        VMCOREINFO_SYMBOL(node_data);
  74        VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);
  75#endif
  76#ifndef CONFIG_NEED_MULTIPLE_NODES
  77        VMCOREINFO_SYMBOL(contig_page_data);
  78#endif
  79#if defined(CONFIG_PPC64) && defined(CONFIG_SPARSEMEM_VMEMMAP)
  80        VMCOREINFO_SYMBOL(vmemmap_list);
  81        VMCOREINFO_SYMBOL(mmu_vmemmap_psize);
  82        VMCOREINFO_SYMBOL(mmu_psize_defs);
  83        VMCOREINFO_STRUCT_SIZE(vmemmap_backing);
  84        VMCOREINFO_OFFSET(vmemmap_backing, list);
  85        VMCOREINFO_OFFSET(vmemmap_backing, phys);
  86        VMCOREINFO_OFFSET(vmemmap_backing, virt_addr);
  87        VMCOREINFO_STRUCT_SIZE(mmu_psize_def);
  88        VMCOREINFO_OFFSET(mmu_psize_def, shift);
  89#endif
  90}
  91
  92/*
  93 * Do not allocate memory (or fail in any way) in machine_kexec().
  94 * We are past the point of no return, committed to rebooting now.
  95 */
  96void machine_kexec(struct kimage *image)
  97{
  98        int save_ftrace_enabled;
  99
 100        save_ftrace_enabled = __ftrace_enabled_save();
 101
 102        if (ppc_md.machine_kexec)
 103                ppc_md.machine_kexec(image);
 104        else
 105                default_machine_kexec(image);
 106
 107        __ftrace_enabled_restore(save_ftrace_enabled);
 108
 109        /* Fall back to normal restart if we're still alive. */
 110        machine_restart(NULL);
 111        for(;;);
 112}
 113
 114void __init reserve_crashkernel(void)
 115{
 116        unsigned long long crash_size, crash_base;
 117        int ret;
 118
 119        /* use common parsing */
 120        ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
 121                        &crash_size, &crash_base);
 122        if (ret == 0 && crash_size > 0) {
 123                crashk_res.start = crash_base;
 124                crashk_res.end = crash_base + crash_size - 1;
 125        }
 126
 127        if (crashk_res.end == crashk_res.start) {
 128                crashk_res.start = crashk_res.end = 0;
 129                return;
 130        }
 131
 132        /* We might have got these values via the command line or the
 133         * device tree, either way sanitise them now. */
 134
 135        crash_size = resource_size(&crashk_res);
 136
 137#ifndef CONFIG_NONSTATIC_KERNEL
 138        if (crashk_res.start != KDUMP_KERNELBASE)
 139                printk("Crash kernel location must be 0x%x\n",
 140                                KDUMP_KERNELBASE);
 141
 142        crashk_res.start = KDUMP_KERNELBASE;
 143#else
 144        if (!crashk_res.start) {
 145#ifdef CONFIG_PPC64
 146                /*
 147                 * On 64bit we split the RMO in half but cap it at half of
 148                 * a small SLB (128MB) since the crash kernel needs to place
 149                 * itself and some stacks to be in the first segment.
 150                 */
 151                crashk_res.start = min(0x8000000ULL, (ppc64_rma_size / 2));
 152#else
 153                crashk_res.start = KDUMP_KERNELBASE;
 154#endif
 155        }
 156
 157        crash_base = PAGE_ALIGN(crashk_res.start);
 158        if (crash_base != crashk_res.start) {
 159                printk("Crash kernel base must be aligned to 0x%lx\n",
 160                                PAGE_SIZE);
 161                crashk_res.start = crash_base;
 162        }
 163
 164#endif
 165        crash_size = PAGE_ALIGN(crash_size);
 166        crashk_res.end = crashk_res.start + crash_size - 1;
 167
 168        /* The crash region must not overlap the current kernel */
 169        if (overlaps_crashkernel(__pa(_stext), _end - _stext)) {
 170                printk(KERN_WARNING
 171                        "Crash kernel can not overlap current kernel\n");
 172                crashk_res.start = crashk_res.end = 0;
 173                return;
 174        }
 175
 176        /* Crash kernel trumps memory limit */
 177        if (memory_limit && memory_limit <= crashk_res.end) {
 178                memory_limit = crashk_res.end + 1;
 179                printk("Adjusted memory limit for crashkernel, now 0x%llx\n",
 180                       memory_limit);
 181        }
 182
 183        printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
 184                        "for crashkernel (System RAM: %ldMB)\n",
 185                        (unsigned long)(crash_size >> 20),
 186                        (unsigned long)(crashk_res.start >> 20),
 187                        (unsigned long)(memblock_phys_mem_size() >> 20));
 188
 189        memblock_reserve(crashk_res.start, crash_size);
 190}
 191
 192int overlaps_crashkernel(unsigned long start, unsigned long size)
 193{
 194        return (start + size) > crashk_res.start && start <= crashk_res.end;
 195}
 196
 197/* Values we need to export to the second kernel via the device tree. */
 198static phys_addr_t kernel_end;
 199static phys_addr_t crashk_size;
 200
 201static struct property kernel_end_prop = {
 202        .name = "linux,kernel-end",
 203        .length = sizeof(phys_addr_t),
 204        .value = &kernel_end,
 205};
 206
 207static struct property crashk_base_prop = {
 208        .name = "linux,crashkernel-base",
 209        .length = sizeof(phys_addr_t),
 210        .value = &crashk_res.start,
 211};
 212
 213static struct property crashk_size_prop = {
 214        .name = "linux,crashkernel-size",
 215        .length = sizeof(phys_addr_t),
 216        .value = &crashk_size,
 217};
 218
 219static struct property memory_limit_prop = {
 220        .name = "linux,memory-limit",
 221        .length = sizeof(unsigned long long),
 222        .value = &memory_limit,
 223};
 224
 225static void __init export_crashk_values(struct device_node *node)
 226{
 227        struct property *prop;
 228
 229        /* There might be existing crash kernel properties, but we can't
 230         * be sure what's in them, so remove them. */
 231        prop = of_find_property(node, "linux,crashkernel-base", NULL);
 232        if (prop)
 233                of_remove_property(node, prop);
 234
 235        prop = of_find_property(node, "linux,crashkernel-size", NULL);
 236        if (prop)
 237                of_remove_property(node, prop);
 238
 239        if (crashk_res.start != 0) {
 240                of_add_property(node, &crashk_base_prop);
 241                crashk_size = resource_size(&crashk_res);
 242                of_add_property(node, &crashk_size_prop);
 243        }
 244
 245        /*
 246         * memory_limit is required by the kexec-tools to limit the
 247         * crash regions to the actual memory used.
 248         */
 249        of_update_property(node, &memory_limit_prop);
 250}
 251
 252static int __init kexec_setup(void)
 253{
 254        struct device_node *node;
 255        struct property *prop;
 256
 257        node = of_find_node_by_path("/chosen");
 258        if (!node)
 259                return -ENOENT;
 260
 261        /* remove any stale properties so ours can be found */
 262        prop = of_find_property(node, kernel_end_prop.name, NULL);
 263        if (prop)
 264                of_remove_property(node, prop);
 265
 266        /* information needed by userspace when using default_machine_kexec */
 267        kernel_end = __pa(_end);
 268        of_add_property(node, &kernel_end_prop);
 269
 270        export_crashk_values(node);
 271
 272        of_node_put(node);
 273        return 0;
 274}
 275late_initcall(kexec_setup);
 276