LXR linux/arch/arm/kernel/machine

   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
  16extern const unsigned char relocate_new_kernel[];
  17extern const unsigned int relocate_new_kernel_size;
  18
  19extern void setup_mm_for_reboot(char mode);
  20
  21extern unsigned long kexec_start_address;
  22extern unsigned long kexec_indirection_page;
  23extern unsigned long kexec_mach_type;
  24extern unsigned long kexec_boot_atags;
  25
  26static 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
  33int machine_kexec_prepare(struct kimage *image)
  34{
  35        return 0;
  36}
  37
  38void machine_kexec_cleanup(struct kimage *image)
  39{
  40}
  41
  42void machine_crash_nonpanic_core(void *unused)
  43{
  44        struct pt_regs regs;
  45
  46        crash_setup_regs(&regs, 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(&regs, smp_processor_id());
  50        flush_cache_all();
  51
  52        atomic_dec(&waiting_for_crash_ipi);
  53        while (1)
  54                cpu_relax();
  55}
  56
  57void 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/*
  79 * Function pointer to optional machine-specific reinitialization
  80 */
  81void (*kexec_reinit)(void);
  82
  83void machine_kexec(struct kimage *image)
  84{
  85        unsigned long page_list;
  86        unsigned long reboot_code_buffer_phys;
  87        void *reboot_code_buffer;
  88
  89
  90        page_list = image->head & PAGE_MASK;
  91
  92        /* we need both effective and real address here */
  93        reboot_code_buffer_phys =
  94            page_to_pfn(image->control_code_page) << PAGE_SHIFT;
  95        reboot_code_buffer = page_address(image->control_code_page);
  96
  97        /* Prepare parameters for reboot_code_buffer*/
  98        kexec_start_address = image->start;
  99        kexec_indirection_page = page_list;
 100        kexec_mach_type = machine_arch_type;
 101        kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
 102
 103        /* copy our kernel relocation code to the control code page */
 104        memcpy(reboot_code_buffer,
 105               relocate_new_kernel, relocate_new_kernel_size);
 106
 107
 108        flush_icache_range((unsigned long) reboot_code_buffer,
 109                           (unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
 110        printk(KERN_INFO "Bye!\n");
 111
 112        if (kexec_reinit)
 113                kexec_reinit();
 114        local_irq_disable();
 115        local_fiq_disable();
 116        setup_mm_for_reboot(0); /* mode is not used, so just pass 0*/
 117        flush_cache_all();
 118        outer_flush_all();
 119        outer_disable();
 120        cpu_proc_fin();
 121        outer_inv_all();
 122        flush_cache_all();
 123        cpu_reset(reboot_code_buffer_phys);
 124}
 125