git.zerfleddert.de Git - ms2-kexec/blob - machine_kexec.c

   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 void v7_flush_kern_cache_all(void);
  22
  23 extern unsigned long kexec_start_address;
  24 extern unsigned long kexec_indirection_page;
  25 extern unsigned long kexec_mach_type;
  26 extern unsigned long kexec_boot_atags;
  27
  28 static atomic_t waiting_for_crash_ipi;
  29
  30 /*
  31  * Provide a dummy crash_notes definition while crash dump arrives to arm.
  32  * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
  33  */
  34
  35 int machine_kexec_prepare(struct kimage *image)
  36 {
  37         return 0;
  38 }
  39
  40 void machine_kexec_cleanup(struct kimage *image)
  41 {
  42 }
  43
  44 void machine_crash_nonpanic_core(void *unused)
  45 {
  46         struct pt_regs regs;
  47
  48         crash_setup_regs(&regs, NULL);
  49         printk(KERN_DEBUG "CPU %u will stop doing anything useful since another CPU has crashed\n",
  50                smp_processor_id());
  51         crash_save_cpu(&regs, smp_processor_id());
  52         v7_flush_kern_cache_all();
  53
  54         atomic_dec(&waiting_for_crash_ipi);
  55         while (1)
  56                 cpu_relax();
  57 }
  58
  59 void machine_crash_shutdown(struct pt_regs *regs)
  60 {
  61         unsigned long msecs;
  62
  63         local_irq_disable();
  64
  65         atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
  66         smp_call_function(machine_crash_nonpanic_core, NULL, false);
  67         msecs = 1000; /* Wait at most a second for the other cpus to stop */
  68         while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
  69                 mdelay(1);
  70                 msecs--;
  71         }
  72         if (atomic_read(&waiting_for_crash_ipi) > 0)
  73                 printk(KERN_WARNING "Non-crashing CPUs did not react to IPI\n");
  74
  75         crash_save_cpu(regs, smp_processor_id());
  76
  77         printk(KERN_INFO "Loading crashdump kernel...\n");
  78 }
  79
  80 /*
  81  * Function pointer to optional machine-specific reinitialization
  82  */
  83 void (*kexec_reinit)(void);
  84
  85 void machine_kexec(struct kimage *image)
  86 {
  87         unsigned long page_list;
  88         unsigned long reboot_code_buffer_phys;
  89         void *reboot_code_buffer;
  90
  91         page_list = image->head & PAGE_MASK;
  92
  93         /* we need both effective and real address here */
  94         reboot_code_buffer_phys =
  95             page_to_pfn(image->control_code_page) << PAGE_SHIFT;
  96         reboot_code_buffer = page_address(image->control_code_page);
  97
  98         /* Prepare parameters for reboot_code_buffer*/
  99         kexec_start_address = image->start;
 100         kexec_indirection_page = page_list;
 101         kexec_mach_type = machine_arch_type;
 102         kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
 103
 104         /* copy our kernel relocation code to the control code page */
 105         memcpy(reboot_code_buffer,
 106                relocate_new_kernel, relocate_new_kernel_size);
 107
 108
 109         flush_icache_range((unsigned long) reboot_code_buffer,
 110                            (unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
 111         printk(KERN_INFO "Bye!\n");
 112
 113         if (kexec_reinit)
 114                 kexec_reinit();
 115         local_irq_disable();
 116         local_fiq_disable();
 117         setup_mm_for_reboot(0); /* mode is not used, so just pass 0*/
 118         v7_flush_kern_cache_all();
 119 #ifdef CONFIG_OUTER_CACHE
 120         outer_flush_all();
 121         outer_disable();
 122 #endif
 123         cpu_proc_fin();
 124 #ifdef CONFIG_OUTER_CACHE
 125         outer_inv_all();
 126 #endif
 127         //v7_flush_kern_cache_all();
 128         cpu_reset(reboot_code_buffer_phys);
 129 }