From: Nicolas Schichan Date: Wed, 18 Oct 2006 13:14:55 +0000 (+0200) Subject: [MIPS] Add support for kexec X-Git-Tag: v2.6.20-rc1~34^2~40^2~469^2~18 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=583bb86fbb9e85287f020fe4eb5352a0ec3c66a3;p=linux-2.6 [MIPS] Add support for kexec A tiny userland application loading the kernel and invoking kexec_load for mips is available here: http://chac.le-poulpe.net/~nico/kexec/kexec-2006-10-18.tar.gz Signed-off-by: Ralf Baechle --- diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 1443024b1c..c0da0ffe8d 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -766,6 +766,23 @@ config TOSHIBA_RBTX4938 endchoice +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. + + The name comes from the similiarity to the exec system call. + + 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. As of this writing the exact hardware interface is + strongly in flux, so no good recommendation can be made. + source "arch/mips/ddb5xxx/Kconfig" source "arch/mips/gt64120/ev64120/Kconfig" source "arch/mips/jazz/Kconfig" diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile index 6bfbbed089..f35b739d0a 100644 --- a/arch/mips/kernel/Makefile +++ b/arch/mips/kernel/Makefile @@ -67,6 +67,8 @@ obj-$(CONFIG_64BIT) += cpu-bugs64.o obj-$(CONFIG_I8253) += i8253.o +obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o + CFLAGS_cpu-bugs64.o = $(shell if $(CC) $(CFLAGS) -Wa,-mdaddi -c -o /dev/null -xc /dev/null >/dev/null 2>&1; then echo "-DHAVE_AS_SET_DADDI"; fi) EXTRA_AFLAGS := $(CFLAGS) diff --git a/arch/mips/kernel/machine_kexec.c b/arch/mips/kernel/machine_kexec.c new file mode 100644 index 0000000000..e0ad754c7e --- /dev/null +++ b/arch/mips/kernel/machine_kexec.c @@ -0,0 +1,85 @@ +/* + * machine_kexec.c for kexec + * Created by on Thu Oct 12 15:15:06 2006 + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#include +#include +#include + +#include +#include + +const extern unsigned char relocate_new_kernel[]; +const extern unsigned int relocate_new_kernel_size; + +extern unsigned long kexec_start_address; +extern unsigned long kexec_indirection_page; + +int +machine_kexec_prepare(struct kimage *kimage) +{ + return 0; +} + +void +machine_kexec_cleanup(struct kimage *kimage) +{ +} + +void +machine_shutdown(void) +{ +} + +void +machine_crash_shutdown(struct pt_regs *regs) +{ +} + +void +machine_kexec(struct kimage *image) +{ + unsigned long reboot_code_buffer; + unsigned long entry; + unsigned long *ptr; + + reboot_code_buffer = + (unsigned long)page_address(image->control_code_page); + + kexec_start_address = image->start; + kexec_indirection_page = phys_to_virt(image->head & PAGE_MASK); + + memcpy((void*)reboot_code_buffer, relocate_new_kernel, + relocate_new_kernel_size); + + /* + * The generic kexec code builds a page list with physical + * addresses. they are directly accessible through KSEG0 (or + * CKSEG0 or XPHYS if on 64bit system), hence the + * pys_to_virt() call. + */ + for (ptr = &image->head; (entry = *ptr) && !(entry &IND_DONE); + ptr = (entry & IND_INDIRECTION) ? + phys_to_virt(entry & PAGE_MASK) : ptr + 1) { + if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION || + *ptr & IND_DESTINATION) + *ptr = phys_to_virt(*ptr); + } + + /* + * we do not want to be bothered. + */ + local_irq_disable(); + + flush_icache_range(reboot_code_buffer, + reboot_code_buffer + KEXEC_CONTROL_CODE_SIZE); + + printk("Will call new kernel at %08x\n", image->start); + printk("Bye ...\n"); + flush_cache_all(); + ((void (*)(void))reboot_code_buffer)(); +} diff --git a/arch/mips/kernel/relocate_kernel.S b/arch/mips/kernel/relocate_kernel.S new file mode 100644 index 0000000000..a3f0d00c13 --- /dev/null +++ b/arch/mips/kernel/relocate_kernel.S @@ -0,0 +1,80 @@ +/* + * relocate_kernel.S for kexec + * Created by on Thu Oct 12 17:49:57 2006 + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#include +#include +#include +#include +#include +#include +#include + + .globl relocate_new_kernel +relocate_new_kernel: + + PTR_L s0, kexec_indirection_page + PTR_L s1, kexec_start_address + +process_entry: + PTR_L s2, (s0) + PTR_ADD s0, s0, SZREG + + /* destination page */ + and s3, s2, 0x1 + beq s3, zero, 1f + and s4, s2, ~0x1 /* store destination addr in s4 */ + move a0, s4 + b process_entry + +1: + /* indirection page, update s0 */ + and s3, s2, 0x2 + beq s3, zero, 1f + and s0, s2, ~0x2 + b process_entry + +1: + /* done page */ + and s3, s2, 0x4 + beq s3, zero, 1f + b done +1: + /* source page */ + and s3, s2, 0x8 + beq s3, zero, process_entry + and s2, s2, ~0x8 + li s6, (1 << PAGE_SHIFT) / SZREG + +copy_word: + /* copy page word by word */ + REG_L s5, (s2) + REG_S s5, (s4) + INT_ADD s4, s4, SZREG + INT_ADD s2, s2, SZREG + INT_SUB s6, s6, 1 + beq s6, zero, process_entry + b copy_word + b process_entry + +done: + /* jump to kexec_start_address */ + j s1 + + .globl kexec_start_address +kexec_start_address: + .long 0x0 + + .globl kexec_indirection_page +kexec_indirection_page: + .long 0x0 + +relocate_new_kernel_end: + + .globl relocate_new_kernel_size +relocate_new_kernel_size: + .long relocate_new_kernel_end - relocate_new_kernel diff --git a/arch/mips/kernel/scall32-o32.S b/arch/mips/kernel/scall32-o32.S index a95f37de08..7c0b3936ba 100644 --- a/arch/mips/kernel/scall32-o32.S +++ b/arch/mips/kernel/scall32-o32.S @@ -653,7 +653,7 @@ einval: li v0, -EINVAL sys sys_move_pages 6 sys sys_set_robust_list 2 sys sys_get_robust_list 3 /* 4310 */ - sys sys_ni_syscall 0 + sys sys_kexec_load 4 sys sys_getcpu 3 sys sys_epoll_pwait 6 .endm diff --git a/arch/mips/kernel/scall64-64.S b/arch/mips/kernel/scall64-64.S index 8fb0f60f65..e569b846e9 100644 --- a/arch/mips/kernel/scall64-64.S +++ b/arch/mips/kernel/scall64-64.S @@ -468,6 +468,6 @@ sys_call_table: PTR sys_move_pages PTR sys_set_robust_list PTR sys_get_robust_list - PTR sys_ni_syscall /* 5270 */ + PTR sys_kexec_load /* 5270 */ PTR sys_getcpu PTR sys_epoll_pwait diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S index 0da5ca2040..5b18f265d7 100644 --- a/arch/mips/kernel/scall64-n32.S +++ b/arch/mips/kernel/scall64-n32.S @@ -394,6 +394,6 @@ EXPORT(sysn32_call_table) PTR sys_move_pages PTR compat_sys_set_robust_list PTR compat_sys_get_robust_list - PTR sys_ni_syscall + PTR compat_sys_kexec_load PTR sys_getcpu PTR sys_epoll_pwait diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S index b9d00cae8b..e91379c1be 100644 --- a/arch/mips/kernel/scall64-o32.S +++ b/arch/mips/kernel/scall64-o32.S @@ -516,7 +516,7 @@ sys_call_table: PTR compat_sys_move_pages PTR compat_sys_set_robust_list PTR compat_sys_get_robust_list /* 4310 */ - PTR sys_ni_syscall + PTR compat_sys_kexec_load PTR sys_getcpu PTR sys_epoll_pwait .size sys_call_table,.-sys_call_table diff --git a/include/asm-mips/kexec.h b/include/asm-mips/kexec.h new file mode 100644 index 0000000000..b25267ebcb --- /dev/null +++ b/include/asm-mips/kexec.h @@ -0,0 +1,32 @@ +/* + * kexec.h for kexec + * Created by on Thu Oct 12 14:59:34 2006 + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#ifndef _MIPS_KEXEC +# define _MIPS_KEXEC + +/* Maximum physical address we can use pages from */ +#define KEXEC_SOURCE_MEMORY_LIMIT (0x20000000) +/* Maximum address we can reach in physical address mode */ +#define KEXEC_DESTINATION_MEMORY_LIMIT (0x20000000) + /* Maximum address we can use for the control code buffer */ +#define KEXEC_CONTROL_MEMORY_LIMIT (0x20000000) + +#define KEXEC_CONTROL_CODE_SIZE 4096 + +/* The native architecture */ +#define KEXEC_ARCH KEXEC_ARCH_MIPS + +#define MAX_NOTE_BYTES 1024 + +static inline void crash_setup_regs(struct pt_regs *newregs, + struct pt_regs *oldregs) +{ + /* Dummy implementation for now */ +} + +#endif /* !_MIPS_KEXEC */ diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 6427949ddf..a4ede62b33 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -122,6 +122,8 @@ extern struct kimage *kexec_crash_image; #define KEXEC_ARCH_IA_64 (50 << 16) #define KEXEC_ARCH_S390 (22 << 16) #define KEXEC_ARCH_SH (42 << 16) +#define KEXEC_ARCH_MIPS_LE (10 << 16) +#define KEXEC_ARCH_MIPS ( 8 << 16) #define KEXEC_FLAGS (KEXEC_ON_CRASH) /* List of defined/legal kexec flags */