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        this_cpu_disable_ftrace();
 102
 103        if (ppc_md.machine_kexec)
 104                ppc_md.machine_kexec(image);
 105        else
 106                default_machine_kexec(image);
 107
 108        this_cpu_enable_ftrace();
 109        __ftrace_enabled_restore(save_ftrace_enabled);
 110
 111        /* Fall back to normal restart if we're still alive. */
 112        machine_restart(NULL);
 113        for(;;);
 114}
 115
 116void __init reserve_crashkernel(void)
 117{
 118        unsigned long long crash_size, crash_base;
 119        int ret;
 120
 121        /* use common parsing */
 122        ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
 123                        &crash_size, &crash_base);
 124        if (ret == 0 && crash_size > 0) {
 125                crashk_res.start = crash_base;
 126                crashk_res.end = crash_base + crash_size - 1;
 127        }
 128
 129        if (crashk_res.end == crashk_res.start) {
 130                crashk_res.start = crashk_res.end = 0;
 131                return;
 132        }
 133
 134        /* We might have got these values via the command line or the
 135         * device tree, either way sanitise them now. */
 136
 137        crash_size = resource_size(&crashk_res);
 138
 139#ifndef CONFIG_NONSTATIC_KERNEL
 140        if (crashk_res.start != KDUMP_KERNELBASE)
 141                printk("Crash kernel location must be 0x%x\n",
 142                                KDUMP_KERNELBASE);
 143
 144        crashk_res.start = KDUMP_KERNELBASE;
 145#else
 146        if (!crashk_res.start) {
 147#ifdef CONFIG_PPC64
 148                /*
 149                 * On 64bit we split the RMO in half but cap it at half of
 150                 * a small SLB (128MB) since the crash kernel needs to place
 151                 * itself and some stacks to be in the first segment.
 152                 */
 153                crashk_res.start = min(0x8000000ULL, (ppc64_rma_size / 2));
 154#else
 155                crashk_res.start = KDUMP_KERNELBASE;
 156#endif
 157        }
 158
 159        crash_base = PAGE_ALIGN(crashk_res.start);
 160        if (crash_base != crashk_res.start) {
 161                printk("Crash kernel base must be aligned to 0x%lx\n",
 162                                PAGE_SIZE);
 163                crashk_res.start = crash_base;
 164        }
 165
 166#endif
 167        crash_size = PAGE_ALIGN(crash_size);
 168        crashk_res.end = crashk_res.start + crash_size - 1;
 169
 170        /* The crash region must not overlap the current kernel */
 171        if (overlaps_crashkernel(__pa(_stext), _end - _stext)) {
 172                printk(KERN_WARNING
 173                        "Crash kernel can not overlap current kernel\n");
 174                crashk_res.start = crashk_res.end = 0;
 175                return;
 176        }
 177
 178        /* Crash kernel trumps memory limit */
 179        if (memory_limit && memory_limit <= crashk_res.end) {
 180                memory_limit = crashk_res.end + 1;
 181                printk("Adjusted memory limit for crashkernel, now 0x%llx\n",
 182                       memory_limit);
 183        }
 184
 185        printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
 186                        "for crashkernel (System RAM: %ldMB)\n",
 187                        (unsigned long)(crash_size >> 20),
 188                        (unsigned long)(crashk_res.start >> 20),
 189                        (unsigned long)(memblock_phys_mem_size() >> 20));
 190
 191        memblock_reserve(crashk_res.start, crash_size);
 192}
 193
 194int overlaps_crashkernel(unsigned long start, unsigned long size)
 195{
 196        return (start + size) > crashk_res.start && start <= crashk_res.end;
 197}
 198
 199/* Values we need to export to the second kernel via the device tree. */
 200static phys_addr_t kernel_end;
 201static phys_addr_t crashk_base;
 202static phys_addr_t crashk_size;
 203static unsigned long long mem_limit;
 204
 205static struct property kernel_end_prop = {
 206        .name = "linux,kernel-end",
 207        .length = sizeof(phys_addr_t),
 208        .value = &kernel_end,
 209};
 210
 211static struct property crashk_base_prop = {
 212        .name = "linux,crashkernel-base",
 213        .length = sizeof(phys_addr_t),
 214        .value = &crashk_base
 215};
 216
 217static struct property crashk_size_prop = {
 218        .name = "linux,crashkernel-size",
 219        .length = sizeof(phys_addr_t),
 220        .value = &crashk_size,
 221};
 222
 223static struct property memory_limit_prop = {
 224        .name = "linux,memory-limit",
 225        .length = sizeof(unsigned long long),
 226        .value = &mem_limit,
 227};
 228
 229#define cpu_to_be_ulong __PASTE(cpu_to_be, BITS_PER_LONG)
 230
 231static void __init export_crashk_values(struct device_node *node)
 232{
 233        /* There might be existing crash kernel properties, but we can't
 234         * be sure what's in them, so remove them. */
 235        of_remove_property(node, of_find_property(node,
 236                                "linux,crashkernel-base", NULL));
 237        of_remove_property(node, of_find_property(node,
 238                                "linux,crashkernel-size", NULL));
 239
 240        if (crashk_res.start != 0) {
 241                crashk_base = cpu_to_be_ulong(crashk_res.start),
 242                of_add_property(node, &crashk_base_prop);
 243                crashk_size = cpu_to_be_ulong(resource_size(&crashk_res));
 244                of_add_property(node, &crashk_size_prop);
 245        }
 246
 247        /*
 248         * memory_limit is required by the kexec-tools to limit the
 249         * crash regions to the actual memory used.
 250         */
 251        mem_limit = cpu_to_be_ulong(memory_limit);
 252        of_update_property(node, &memory_limit_prop);
 253}
 254
 255static int __init kexec_setup(void)
 256{
 257        struct device_node *node;
 258
 259        node = of_find_node_by_path("/chosen");
 260        if (!node)
 261                return -ENOENT;
 262
 263        /* remove any stale properties so ours can be found */
 264        of_remove_property(node, of_find_property(node, kernel_end_prop.name, NULL));
 265
 266        /* information needed by userspace when using default_machine_kexec */
 267        kernel_end = cpu_to_be_ulong(__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