kernel_optimize_test/arch/arm/kernel/machine_kexec.c
Thomas Gleixner ae360a78f4 arm: Disable outer (L2) cache in kexec
kexec does not disable the outer cache before disabling the inner
caches in cpu_proc_fin(). So L2 is enabled across the kexec jump. When
the new kernel enables chaches again, it randomly crashes.

Disabling L2 before calling cpu_proc_fin() cures the problem.

Disabling L2 requires the following new functions: flush_all(),
inv_all() and disable(). Add them to outer_cache_fns and call them
from the kexec code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
2010-10-26 11:39:56 +05:30

88 lines
2.2 KiB
C

/*
* machine_kexec.c - handle transition of Linux booting another kernel
*/
#include <linux/mm.h>
#include <linux/kexec.h>
#include <linux/delay.h>
#include <linux/reboot.h>
#include <linux/io.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
#include <asm/mach-types.h>
extern const unsigned char relocate_new_kernel[];
extern const unsigned int relocate_new_kernel_size;
extern void setup_mm_for_reboot(char mode);
extern unsigned long kexec_start_address;
extern unsigned long kexec_indirection_page;
extern unsigned long kexec_mach_type;
extern unsigned long kexec_boot_atags;
/*
* Provide a dummy crash_notes definition while crash dump arrives to arm.
* This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
*/
int machine_kexec_prepare(struct kimage *image)
{
return 0;
}
void machine_kexec_cleanup(struct kimage *image)
{
}
void machine_crash_shutdown(struct pt_regs *regs)
{
local_irq_disable();
crash_save_cpu(regs, smp_processor_id());
printk(KERN_INFO "Loading crashdump kernel...\n");
}
void machine_kexec(struct kimage *image)
{
unsigned long page_list;
unsigned long reboot_code_buffer_phys;
void *reboot_code_buffer;
page_list = image->head & PAGE_MASK;
/* we need both effective and real address here */
reboot_code_buffer_phys =
page_to_pfn(image->control_code_page) << PAGE_SHIFT;
reboot_code_buffer = page_address(image->control_code_page);
/* Prepare parameters for reboot_code_buffer*/
kexec_start_address = image->start;
kexec_indirection_page = page_list;
kexec_mach_type = machine_arch_type;
kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
/* copy our kernel relocation code to the control code page */
memcpy(reboot_code_buffer,
relocate_new_kernel, relocate_new_kernel_size);
flush_icache_range((unsigned long) reboot_code_buffer,
(unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
printk(KERN_INFO "Bye!\n");
local_irq_disable();
local_fiq_disable();
setup_mm_for_reboot(0); /* mode is not used, so just pass 0*/
flush_cache_all();
outer_flush_all();
outer_disable();
cpu_proc_fin();
outer_inv_all();
flush_cache_all();
cpu_reset(reboot_code_buffer_phys);
}