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 16 extern const unsigned char relocate_new_kernel[]; 17 extern const unsigned int relocate_new_kernel_size; 18 19 extern void setup_mm_for_reboot(char mode); 20 21 extern unsigned long kexec_start_address; 22 extern unsigned long kexec_indirection_page; 23 extern unsigned long kexec_mach_type; 24 extern unsigned long kexec_boot_atags; 25 26 static atomic_t waiting_for_crash_ipi; 27 28 /* 29 * Provide a dummy crash_notes definition while crash dump arrives to arm. 30 * This prevents breakage of crash_notes attribute in kernel/ksysfs.c. 31 */ 32 33 int machine_kexec_prepare(struct kimage *image) 34 { 35 return 0; 36 } 37 38 void machine_kexec_cleanup(struct kimage *image) 39 { 40 } 41 42 void machine_crash_nonpanic_core(void *unused) 43 { 44 struct pt_regs regs; 45 46 crash_setup_regs(®s, NULL); 47 printk(KERN_DEBUG "CPU %u will stop doing anything useful since another CPU has crashed\n", 48 smp_processor_id()); 49 crash_save_cpu(®s, smp_processor_id()); 50 flush_cache_all(); 51 52 atomic_dec(&waiting_for_crash_ipi); 53 while (1) 54 cpu_relax(); 55 } 56 57 void machine_crash_shutdown(struct pt_regs *regs) 58 { 59 unsigned long msecs; 60 61 local_irq_disable(); 62 63 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); 64 smp_call_function(machine_crash_nonpanic_core, NULL, false); 65 msecs = 1000; /* Wait at most a second for the other cpus to stop */ 66 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { 67 mdelay(1); 68 msecs--; 69 } 70 if (atomic_read(&waiting_for_crash_ipi) > 0) 71 printk(KERN_WARNING "Non-crashing CPUs did not react to IPI\n"); 72 73 crash_save_cpu(regs, smp_processor_id()); 74 75 printk(KERN_INFO "Loading crashdump kernel...\n"); 76 } 77 78 void machine_kexec(struct kimage *image) 79 { 80 unsigned long page_list; 81 unsigned long reboot_code_buffer_phys; 82 void *reboot_code_buffer; 83 84 85 page_list = image->head & PAGE_MASK; 86 87 /* we need both effective and real address here */ 88 reboot_code_buffer_phys = 89 page_to_pfn(image->control_code_page) << PAGE_SHIFT; 90 reboot_code_buffer = page_address(image->control_code_page); 91 92 /* Prepare parameters for reboot_code_buffer*/ 93 kexec_start_address = image->start; 94 kexec_indirection_page = page_list; 95 kexec_mach_type = machine_arch_type; 96 kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET; 97 98 /* copy our kernel relocation code to the control code page */ 99 memcpy(reboot_code_buffer, 100 relocate_new_kernel, relocate_new_kernel_size); 101 102 103 flush_icache_range((unsigned long) reboot_code_buffer, 104 (unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE); 105 printk(KERN_INFO "Bye!\n"); 106 107 local_irq_disable(); 108 local_fiq_disable(); 109 setup_mm_for_reboot(0); /* mode is not used, so just pass 0*/ 110 flush_cache_all(); 111 outer_flush_all(); 112 outer_disable(); 113 cpu_proc_fin(); 114 outer_inv_all(); 115 flush_cache_all(); 116 cpu_reset(reboot_code_buffer_phys); 117 } 118