machine_kexec.c revision ac4414e4d3024a3c9ac5f54a734ac77dd7edfdb3
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/prom.h> 22#include <asm/sections.h> 23 24void machine_kexec_mask_interrupts(void) { 25 unsigned int i; 26 27 for_each_irq(i) { 28 struct irq_desc *desc = irq_to_desc(i); 29 30 if (!desc || !desc->chip) 31 continue; 32 33 if (desc->chip->eoi && 34 desc->status & IRQ_INPROGRESS) 35 desc->chip->eoi(i); 36 37 if (desc->chip->mask) 38 desc->chip->mask(i); 39 40 if (desc->chip->disable && 41 !(desc->status & IRQ_DISABLED)) 42 desc->chip->disable(i); 43 } 44} 45 46void machine_crash_shutdown(struct pt_regs *regs) 47{ 48 default_machine_crash_shutdown(regs); 49} 50 51/* 52 * Do what every setup is needed on image and the 53 * reboot code buffer to allow us to avoid allocations 54 * later. 55 */ 56int machine_kexec_prepare(struct kimage *image) 57{ 58 if (ppc_md.machine_kexec_prepare) 59 return ppc_md.machine_kexec_prepare(image); 60 else 61 return default_machine_kexec_prepare(image); 62} 63 64void machine_kexec_cleanup(struct kimage *image) 65{ 66} 67 68void arch_crash_save_vmcoreinfo(void) 69{ 70 71#ifdef CONFIG_NEED_MULTIPLE_NODES 72 VMCOREINFO_SYMBOL(node_data); 73 VMCOREINFO_LENGTH(node_data, MAX_NUMNODES); 74#endif 75#ifndef CONFIG_NEED_MULTIPLE_NODES 76 VMCOREINFO_SYMBOL(contig_page_data); 77#endif 78} 79 80/* 81 * Do not allocate memory (or fail in any way) in machine_kexec(). 82 * We are past the point of no return, committed to rebooting now. 83 */ 84void machine_kexec(struct kimage *image) 85{ 86 int save_ftrace_enabled; 87 88 save_ftrace_enabled = __ftrace_enabled_save(); 89 90 default_machine_kexec(image); 91 92 __ftrace_enabled_restore(save_ftrace_enabled); 93 94 /* Fall back to normal restart if we're still alive. */ 95 machine_restart(NULL); 96 for(;;); 97} 98 99void __init reserve_crashkernel(void) 100{ 101 unsigned long long crash_size, crash_base; 102 int ret; 103 104 /* this is necessary because of memblock_phys_mem_size() */ 105 memblock_analyze(); 106 107 /* use common parsing */ 108 ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), 109 &crash_size, &crash_base); 110 if (ret == 0 && crash_size > 0) { 111 crashk_res.start = crash_base; 112 crashk_res.end = crash_base + crash_size - 1; 113 } 114 115 if (crashk_res.end == crashk_res.start) { 116 crashk_res.start = crashk_res.end = 0; 117 return; 118 } 119 120 /* We might have got these values via the command line or the 121 * device tree, either way sanitise them now. */ 122 123 crash_size = crashk_res.end - crashk_res.start + 1; 124 125#ifndef CONFIG_RELOCATABLE 126 if (crashk_res.start != KDUMP_KERNELBASE) 127 printk("Crash kernel location must be 0x%x\n", 128 KDUMP_KERNELBASE); 129 130 crashk_res.start = KDUMP_KERNELBASE; 131#else 132 if (!crashk_res.start) { 133 /* 134 * unspecified address, choose a region of specified size 135 * can overlap with initrd (ignoring corruption when retained) 136 * ppc64 requires kernel and some stacks to be in first segemnt 137 */ 138 crashk_res.start = KDUMP_KERNELBASE; 139 } 140 141 crash_base = PAGE_ALIGN(crashk_res.start); 142 if (crash_base != crashk_res.start) { 143 printk("Crash kernel base must be aligned to 0x%lx\n", 144 PAGE_SIZE); 145 crashk_res.start = crash_base; 146 } 147 148#endif 149 crash_size = PAGE_ALIGN(crash_size); 150 crashk_res.end = crashk_res.start + crash_size - 1; 151 152 /* The crash region must not overlap the current kernel */ 153 if (overlaps_crashkernel(__pa(_stext), _end - _stext)) { 154 printk(KERN_WARNING 155 "Crash kernel can not overlap current kernel\n"); 156 crashk_res.start = crashk_res.end = 0; 157 return; 158 } 159 160 /* Crash kernel trumps memory limit */ 161 if (memory_limit && memory_limit <= crashk_res.end) { 162 memory_limit = crashk_res.end + 1; 163 printk("Adjusted memory limit for crashkernel, now 0x%llx\n", 164 (unsigned long long)memory_limit); 165 } 166 167 printk(KERN_INFO "Reserving %ldMB of memory at %ldMB " 168 "for crashkernel (System RAM: %ldMB)\n", 169 (unsigned long)(crash_size >> 20), 170 (unsigned long)(crashk_res.start >> 20), 171 (unsigned long)(memblock_phys_mem_size() >> 20)); 172 173 memblock_reserve(crashk_res.start, crash_size); 174} 175 176int overlaps_crashkernel(unsigned long start, unsigned long size) 177{ 178 return (start + size) > crashk_res.start && start <= crashk_res.end; 179} 180 181/* Values we need to export to the second kernel via the device tree. */ 182static phys_addr_t kernel_end; 183static phys_addr_t crashk_size; 184 185static struct property kernel_end_prop = { 186 .name = "linux,kernel-end", 187 .length = sizeof(phys_addr_t), 188 .value = &kernel_end, 189}; 190 191static struct property crashk_base_prop = { 192 .name = "linux,crashkernel-base", 193 .length = sizeof(phys_addr_t), 194 .value = &crashk_res.start, 195}; 196 197static struct property crashk_size_prop = { 198 .name = "linux,crashkernel-size", 199 .length = sizeof(phys_addr_t), 200 .value = &crashk_size, 201}; 202 203static void __init export_crashk_values(struct device_node *node) 204{ 205 struct property *prop; 206 207 /* There might be existing crash kernel properties, but we can't 208 * be sure what's in them, so remove them. */ 209 prop = of_find_property(node, "linux,crashkernel-base", NULL); 210 if (prop) 211 prom_remove_property(node, prop); 212 213 prop = of_find_property(node, "linux,crashkernel-size", NULL); 214 if (prop) 215 prom_remove_property(node, prop); 216 217 if (crashk_res.start != 0) { 218 prom_add_property(node, &crashk_base_prop); 219 crashk_size = crashk_res.end - crashk_res.start + 1; 220 prom_add_property(node, &crashk_size_prop); 221 } 222} 223 224static int __init kexec_setup(void) 225{ 226 struct device_node *node; 227 struct property *prop; 228 229 node = of_find_node_by_path("/chosen"); 230 if (!node) 231 return -ENOENT; 232 233 /* remove any stale properties so ours can be found */ 234 prop = of_find_property(node, kernel_end_prop.name, NULL); 235 if (prop) 236 prom_remove_property(node, prop); 237 238 /* information needed by userspace when using default_machine_kexec */ 239 kernel_end = __pa(_end); 240 prom_add_property(node, &kernel_end_prop); 241 242 export_crashk_values(node); 243 244 of_node_put(node); 245 return 0; 246} 247late_initcall(kexec_setup); 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