machine_kexec.c revision 0f890c8d205e47f7cb0d381ffba582a170fd4f72
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 = resource_size(&crashk_res); 130 131#ifndef CONFIG_NONSTATIC_KERNEL 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#ifdef CONFIG_PPC64 140 /* 141 * On 64bit we split the RMO in half but cap it at half of 142 * a small SLB (128MB) since the crash kernel needs to place 143 * itself and some stacks to be in the first segment. 144 */ 145 crashk_res.start = min(0x80000000ULL, (ppc64_rma_size / 2)); 146#else 147 crashk_res.start = KDUMP_KERNELBASE; 148#endif 149 } 150 151 crash_base = PAGE_ALIGN(crashk_res.start); 152 if (crash_base != crashk_res.start) { 153 printk("Crash kernel base must be aligned to 0x%lx\n", 154 PAGE_SIZE); 155 crashk_res.start = crash_base; 156 } 157 158#endif 159 crash_size = PAGE_ALIGN(crash_size); 160 crashk_res.end = crashk_res.start + crash_size - 1; 161 162 /* The crash region must not overlap the current kernel */ 163 if (overlaps_crashkernel(__pa(_stext), _end - _stext)) { 164 printk(KERN_WARNING 165 "Crash kernel can not overlap current kernel\n"); 166 crashk_res.start = crashk_res.end = 0; 167 return; 168 } 169 170 /* Crash kernel trumps memory limit */ 171 if (memory_limit && memory_limit <= crashk_res.end) { 172 memory_limit = crashk_res.end + 1; 173 printk("Adjusted memory limit for crashkernel, now 0x%llx\n", 174 (unsigned long long)memory_limit); 175 } 176 177 printk(KERN_INFO "Reserving %ldMB of memory at %ldMB " 178 "for crashkernel (System RAM: %ldMB)\n", 179 (unsigned long)(crash_size >> 20), 180 (unsigned long)(crashk_res.start >> 20), 181 (unsigned long)(memblock_phys_mem_size() >> 20)); 182 183 memblock_reserve(crashk_res.start, crash_size); 184} 185 186int overlaps_crashkernel(unsigned long start, unsigned long size) 187{ 188 return (start + size) > crashk_res.start && start <= crashk_res.end; 189} 190 191/* Values we need to export to the second kernel via the device tree. */ 192static phys_addr_t kernel_end; 193static phys_addr_t crashk_size; 194 195static struct property kernel_end_prop = { 196 .name = "linux,kernel-end", 197 .length = sizeof(phys_addr_t), 198 .value = &kernel_end, 199}; 200 201static struct property crashk_base_prop = { 202 .name = "linux,crashkernel-base", 203 .length = sizeof(phys_addr_t), 204 .value = &crashk_res.start, 205}; 206 207static struct property crashk_size_prop = { 208 .name = "linux,crashkernel-size", 209 .length = sizeof(phys_addr_t), 210 .value = &crashk_size, 211}; 212 213static void __init export_crashk_values(struct device_node *node) 214{ 215 struct property *prop; 216 217 /* There might be existing crash kernel properties, but we can't 218 * be sure what's in them, so remove them. */ 219 prop = of_find_property(node, "linux,crashkernel-base", NULL); 220 if (prop) 221 prom_remove_property(node, prop); 222 223 prop = of_find_property(node, "linux,crashkernel-size", NULL); 224 if (prop) 225 prom_remove_property(node, prop); 226 227 if (crashk_res.start != 0) { 228 prom_add_property(node, &crashk_base_prop); 229 crashk_size = resource_size(&crashk_res); 230 prom_add_property(node, &crashk_size_prop); 231 } 232} 233 234static int __init kexec_setup(void) 235{ 236 struct device_node *node; 237 struct property *prop; 238 239 node = of_find_node_by_path("/chosen"); 240 if (!node) 241 return -ENOENT; 242 243 /* remove any stale properties so ours can be found */ 244 prop = of_find_property(node, kernel_end_prop.name, NULL); 245 if (prop) 246 prom_remove_property(node, prop); 247 248 /* information needed by userspace when using default_machine_kexec */ 249 kernel_end = __pa(_end); 250 prom_add_property(node, &kernel_end_prop); 251 252 export_crashk_values(node); 253 254 of_node_put(node); 255 return 0; 256} 257late_initcall(kexec_setup); 258