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-rw-r--r--arch/arm/Kconfig14
-rw-r--r--arch/arm/kernel/Makefile1
-rw-r--r--arch/arm/kernel/calls.S1
-rw-r--r--arch/arm/kernel/machine_kexec.c78
-rw-r--r--arch/arm/kernel/relocate_kernel.S74
5 files changed, 168 insertions, 0 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 6783c2e5512d..a8298949d166 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -738,6 +738,20 @@ config XIP_PHYS_ADDR
be linked for and stored to. This address is dependent on your
own flash usage.
+config KEXEC
+ bool "Kexec system call (EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ help
+ kexec is a system call that implements the ability to shutdown your
+ current kernel, and to start another kernel. It is like a reboot
+ but it is indepedent of the system firmware. And like a reboot
+ you can start any kernel with it, not just Linux.
+
+ It is an ongoing process to be certain the hardware in a machine
+ is properly shutdown, so do not be surprised if this code does not
+ initially work for you. It may help to enable device hotplugging
+ support.
+
endmenu
if (ARCH_SA1100 || ARCH_INTEGRATOR || ARCH_OMAP || ARCH_IMX )
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index ab06a86e85d5..d5002889773e 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_ARTHUR) += arthur.o
obj-$(CONFIG_ISA_DMA) += dma-isa.o
obj-$(CONFIG_PCI) += bios32.o isa.o
obj-$(CONFIG_SMP) += smp.o
+obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o
obj-$(CONFIG_OABI_COMPAT) += sys_oabi-compat.o
obj-$(CONFIG_CRUNCH) += crunch.o crunch-bits.o
diff --git a/arch/arm/kernel/calls.S b/arch/arm/kernel/calls.S
index f7598cbc7ec5..ae89cdd82b16 100644
--- a/arch/arm/kernel/calls.S
+++ b/arch/arm/kernel/calls.S
@@ -356,6 +356,7 @@
CALL(sys_move_pages)
/* 345 */ CALL(sys_getcpu)
CALL(sys_ni_syscall) /* eventually epoll_pwait */
+ CALL(sys_kexec_load)
#ifndef syscalls_counted
.equ syscalls_padding, ((NR_syscalls + 3) & ~3) - NR_syscalls
#define syscalls_counted
diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c
new file mode 100644
index 000000000000..863c66454f2b
--- /dev/null
+++ b/arch/arm/kernel/machine_kexec.c
@@ -0,0 +1,78 @@
+/*
+ * 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 <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/mmu_context.h>
+#include <asm/io.h>
+#include <asm/cacheflush.h>
+#include <asm/mach-types.h>
+
+const extern unsigned char relocate_new_kernel[];
+const extern 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;
+
+/*
+ * 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_shutdown(void)
+{
+}
+
+void machine_crash_shutdown(struct pt_regs *regs)
+{
+}
+
+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;
+
+ /* 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_CODE_SIZE);
+ printk(KERN_INFO "Bye!\n");
+
+ cpu_proc_fin();
+ setup_mm_for_reboot(0); /* mode is not used, so just pass 0*/
+ cpu_reset(reboot_code_buffer_phys);
+}
diff --git a/arch/arm/kernel/relocate_kernel.S b/arch/arm/kernel/relocate_kernel.S
new file mode 100644
index 000000000000..7baadae7cb27
--- /dev/null
+++ b/arch/arm/kernel/relocate_kernel.S
@@ -0,0 +1,74 @@
+/*
+ * relocate_kernel.S - put the kernel image in place to boot
+ */
+
+#include <asm/kexec.h>
+
+ .globl relocate_new_kernel
+relocate_new_kernel:
+
+ ldr r0,kexec_indirection_page
+ ldr r1,kexec_start_address
+
+
+0: /* top, read another word for the indirection page */
+ ldr r3, [r0],#4
+
+ /* Is it a destination page. Put destination address to r4 */
+ tst r3,#1,0
+ beq 1f
+ bic r4,r3,#1
+ b 0b
+1:
+ /* Is it an indirection page */
+ tst r3,#2,0
+ beq 1f
+ bic r0,r3,#2
+ b 0b
+1:
+
+ /* are we done ? */
+ tst r3,#4,0
+ beq 1f
+ b 2f
+
+1:
+ /* is it source ? */
+ tst r3,#8,0
+ beq 0b
+ bic r3,r3,#8
+ mov r6,#1024
+9:
+ ldr r5,[r3],#4
+ str r5,[r4],#4
+ subs r6,r6,#1
+ bne 9b
+ b 0b
+
+2:
+ /* Jump to relocated kernel */
+ mov lr,r1
+ mov r0,#0
+ ldr r1,kexec_mach_type
+ mov r2,#0
+ mov pc,lr
+
+ .globl kexec_start_address
+kexec_start_address:
+ .long 0x0
+
+ .globl kexec_indirection_page
+kexec_indirection_page:
+ .long 0x0
+
+ .globl kexec_mach_type
+kexec_mach_type:
+ .long 0x0
+
+relocate_new_kernel_end:
+
+ .globl relocate_new_kernel_size
+relocate_new_kernel_size:
+ .long relocate_new_kernel_end - relocate_new_kernel
+
+