machine_kexec.c revision ec775d0e70eb6b7116406b3441cb8501c2849dd2
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 struct irq_chip *chip; 30 31 if (!desc) 32 continue; 33 34 chip = irq_desc_get_chip(desc); 35 if (!chip) 36 continue; 37 38 if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data)) 39 chip->irq_eoi(&desc->irq_data); 40 41 if (chip->irq_mask) 42 chip->irq_mask(&desc->irq_data); 43 44 if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data)) 45 chip->irq_disable(&desc->irq_data); 46 } 47} 48 49void machine_crash_shutdown(struct pt_regs *regs) 50{ 51 default_machine_crash_shutdown(regs); 52} 53 54/* 55 * Do what every setup is needed on image and the 56 * reboot code buffer to allow us to avoid allocations 57 * later. 58 */ 59int machine_kexec_prepare(struct kimage *image) 60{ 61 if (ppc_md.machine_kexec_prepare) 62 return ppc_md.machine_kexec_prepare(image); 63 else 64 return default_machine_kexec_prepare(image); 65} 66 67void machine_kexec_cleanup(struct kimage *image) 68{ 69} 70 71void arch_crash_save_vmcoreinfo(void) 72{ 73 74#ifdef CONFIG_NEED_MULTIPLE_NODES 75 VMCOREINFO_SYMBOL(node_data); 76 VMCOREINFO_LENGTH(node_data, MAX_NUMNODES); 77#endif 78#ifndef CONFIG_NEED_MULTIPLE_NODES 79 VMCOREINFO_SYMBOL(contig_page_data); 80#endif 81} 82 83/* 84 * Do not allocate memory (or fail in any way) in machine_kexec(). 85 * We are past the point of no return, committed to rebooting now. 86 */ 87void machine_kexec(struct kimage *image) 88{ 89 int save_ftrace_enabled; 90 91 save_ftrace_enabled = __ftrace_enabled_save(); 92 93 if (ppc_md.machine_kexec) 94 ppc_md.machine_kexec(image); 95 else 96 default_machine_kexec(image); 97 98 __ftrace_enabled_restore(save_ftrace_enabled); 99 100 /* Fall back to normal restart if we're still alive. */ 101 machine_restart(NULL); 102 for(;;); 103} 104 105void __init reserve_crashkernel(void) 106{ 107 unsigned long long crash_size, crash_base; 108 int ret; 109 110 /* this is necessary because of memblock_phys_mem_size() */ 111 memblock_analyze(); 112 113 /* use common parsing */ 114 ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), 115 &crash_size, &crash_base); 116 if (ret == 0 && crash_size > 0) { 117 crashk_res.start = crash_base; 118 crashk_res.end = crash_base + crash_size - 1; 119 } 120 121 if (crashk_res.end == crashk_res.start) { 122 crashk_res.start = crashk_res.end = 0; 123 return; 124 } 125 126 /* We might have got these values via the command line or the 127 * device tree, either way sanitise them now. */ 128 129 crash_size = crashk_res.end - crashk_res.start + 1; 130 131#ifndef CONFIG_RELOCATABLE 132 if (crashk_res.start != KDUMP_KERNELBASE) 133 printk("Crash kernel location must be 0x%x\n", 134 KDUMP_KERNELBASE); 135 136 crashk_res.start = KDUMP_KERNELBASE; 137#else 138 if (!crashk_res.start) { 139 /* 140 * unspecified address, choose a region of specified size 141 * can overlap with initrd (ignoring corruption when retained) 142 * ppc64 requires kernel and some stacks to be in first segemnt 143 */ 144 crashk_res.start = KDUMP_KERNELBASE; 145 } 146 147 crash_base = PAGE_ALIGN(crashk_res.start); 148 if (crash_base != crashk_res.start) { 149 printk("Crash kernel base must be aligned to 0x%lx\n", 150 PAGE_SIZE); 151 crashk_res.start = crash_base; 152 } 153 154#endif 155 crash_size = PAGE_ALIGN(crash_size); 156 crashk_res.end = crashk_res.start + crash_size - 1; 157 158 /* The crash region must not overlap the current kernel */ 159 if (overlaps_crashkernel(__pa(_stext), _end - _stext)) { 160 printk(KERN_WARNING 161 "Crash kernel can not overlap current kernel\n"); 162 crashk_res.start = crashk_res.end = 0; 163 return; 164 } 165 166 /* Crash kernel trumps memory limit */ 167 if (memory_limit && memory_limit <= crashk_res.end) { 168 memory_limit = crashk_res.end + 1; 169 printk("Adjusted memory limit for crashkernel, now 0x%llx\n", 170 (unsigned long long)memory_limit); 171 } 172 173 printk(KERN_INFO "Reserving %ldMB of memory at %ldMB " 174 "for crashkernel (System RAM: %ldMB)\n", 175 (unsigned long)(crash_size >> 20), 176 (unsigned long)(crashk_res.start >> 20), 177 (unsigned long)(memblock_phys_mem_size() >> 20)); 178 179 memblock_reserve(crashk_res.start, crash_size); 180} 181 182int overlaps_crashkernel(unsigned long start, unsigned long size) 183{ 184 return (start + size) > crashk_res.start && start <= crashk_res.end; 185} 186 187/* Values we need to export to the second kernel via the device tree. */ 188static phys_addr_t kernel_end; 189static phys_addr_t crashk_size; 190 191static struct property kernel_end_prop = { 192 .name = "linux,kernel-end", 193 .length = sizeof(phys_addr_t), 194 .value = &kernel_end, 195}; 196 197static struct property crashk_base_prop = { 198 .name = "linux,crashkernel-base", 199 .length = sizeof(phys_addr_t), 200 .value = &crashk_res.start, 201}; 202 203static struct property crashk_size_prop = { 204 .name = "linux,crashkernel-size", 205 .length = sizeof(phys_addr_t), 206 .value = &crashk_size, 207}; 208 209static void __init export_crashk_values(struct device_node *node) 210{ 211 struct property *prop; 212 213 /* There might be existing crash kernel properties, but we can't 214 * be sure what's in them, so remove them. */ 215 prop = of_find_property(node, "linux,crashkernel-base", NULL); 216 if (prop) 217 prom_remove_property(node, prop); 218 219 prop = of_find_property(node, "linux,crashkernel-size", NULL); 220 if (prop) 221 prom_remove_property(node, prop); 222 223 if (crashk_res.start != 0) { 224 prom_add_property(node, &crashk_base_prop); 225 crashk_size = crashk_res.end - crashk_res.start + 1; 226 prom_add_property(node, &crashk_size_prop); 227 } 228} 229 230static int __init kexec_setup(void) 231{ 232 struct device_node *node; 233 struct property *prop; 234 235 node = of_find_node_by_path("/chosen"); 236 if (!node) 237 return -ENOENT; 238 239 /* remove any stale properties so ours can be found */ 240 prop = of_find_property(node, kernel_end_prop.name, NULL); 241 if (prop) 242 prom_remove_property(node, prop); 243 244 /* information needed by userspace when using default_machine_kexec */ 245 kernel_end = __pa(_end); 246 prom_add_property(node, &kernel_end_prop); 247 248 export_crashk_values(node); 249 250 of_node_put(node); 251 return 0; 252} 253late_initcall(kexec_setup); 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