1 /* 2 * machine_kexec.c - handle transition of Linux booting another kernel 3 */ 4 5 #include <linux/mm.h> 6 #include <linux/kexec.h> 7 #include <linux/delay.h> 8 #include <linux/reboot.h> 9 #include <linux/io.h> 10 #include <asm/pgtable.h> 11 #include <asm/pgalloc.h> 12 #include <asm/mmu_context.h> 13 #include <asm/cacheflush.h> 14 #include <asm/mach-types.h> 15 #include <asm/system.h> 16 17 extern const unsigned char relocate_new_kernel[]; 18 extern const unsigned int relocate_new_kernel_size; 19 20 extern unsigned long kexec_start_address; 21 extern unsigned long kexec_indirection_page; 22 extern unsigned long kexec_mach_type; 23 extern unsigned long kexec_boot_atags; 24 25 static atomic_t waiting_for_crash_ipi; 26 27 /* 28 * Provide a dummy crash_notes definition while crash dump arrives to arm. 29 * This prevents breakage of crash_notes attribute in kernel/ksysfs.c. 30 */ 31 32 int machine_kexec_prepare(struct kimage *image) 33 { 34 return 0; 35 } 36 37 void machine_kexec_cleanup(struct kimage *image) 38 { 39 } 40 41 void machine_crash_nonpanic_core(void *unused) 42 { 43 struct pt_regs regs; 44 45 crash_setup_regs(®s, NULL); 46 printk(KERN_DEBUG "CPU %u will stop doing anything useful since another CPU has crashed\n", 47 smp_processor_id()); 48 crash_save_cpu(®s, smp_processor_id()); 49 flush_cache_all(); 50 51 atomic_dec(&waiting_for_crash_ipi); 52 while (1) 53 cpu_relax(); 54 } 55 56 void machine_crash_shutdown(struct pt_regs *regs) 57 { 58 unsigned long msecs; 59 60 local_irq_disable(); 61 62 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); 63 smp_call_function(machine_crash_nonpanic_core, NULL, false); 64 msecs = 1000; /* Wait at most a second for the other cpus to stop */ 65 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { 66 mdelay(1); 67 msecs--; 68 } 69 if (atomic_read(&waiting_for_crash_ipi) > 0) 70 printk(KERN_WARNING "Non-crashing CPUs did not react to IPI\n"); 71 72 crash_save_cpu(regs, smp_processor_id()); 73 74 printk(KERN_INFO "Loading crashdump kernel...\n"); 75 } 76 77 /* 78 * Function pointer to optional machine-specific reinitialization 79 */ 80 void (*kexec_reinit)(void); 81 82 void machine_kexec(struct kimage *image) 83 { 84 unsigned long page_list; 85 unsigned long reboot_code_buffer_phys; 86 void *reboot_code_buffer; 87 88 89 page_list = image->head & PAGE_MASK; 90 91 /* we need both effective and real address here */ 92 reboot_code_buffer_phys = 93 page_to_pfn(image->control_code_page) << PAGE_SHIFT; 94 reboot_code_buffer = page_address(image->control_code_page); 95 96 /* Prepare parameters for reboot_code_buffer*/ 97 kexec_start_address = image->start; 98 kexec_indirection_page = page_list; 99 kexec_mach_type = machine_arch_type; 100 kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET; 101 102 /* copy our kernel relocation code to the control code page */ 103 memcpy(reboot_code_buffer, 104 relocate_new_kernel, relocate_new_kernel_size); 105 106 107 flush_icache_range((unsigned long) reboot_code_buffer, 108 (unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE); 109 printk(KERN_INFO "Bye!\n"); 110 111 if (kexec_reinit) 112 kexec_reinit(); 113 114 soft_restart(reboot_code_buffer_phys); 115 } 116