diff options
-rw-r--r-- | arch/ppc/Kconfig | 20 | ||||
-rw-r--r-- | arch/ppc/kernel/Makefile | 1 | ||||
-rw-r--r-- | arch/ppc/kernel/machine_kexec.c | 122 | ||||
-rw-r--r-- | arch/ppc/kernel/misc.S | 2 | ||||
-rw-r--r-- | arch/ppc/kernel/relocate_kernel.S | 123 | ||||
-rw-r--r-- | include/asm-ppc/kexec.h | 38 | ||||
-rw-r--r-- | include/asm-ppc/machdep.h | 31 |
7 files changed, 336 insertions, 1 deletions
diff --git a/arch/ppc/Kconfig b/arch/ppc/Kconfig index 979590a9baf9..a7835cd3f51f 100644 --- a/arch/ppc/Kconfig +++ b/arch/ppc/Kconfig @@ -217,6 +217,26 @@ config MATH_EMULATION here. Saying Y here will not hurt performance (on any machine) but will increase the size of the kernel. +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. + + In the GameCube implementation, kexec allows you to load and + run DOL files, including kernel and homebrew DOLs. + source "drivers/cpufreq/Kconfig" config CPU_FREQ_PMAC diff --git a/arch/ppc/kernel/Makefile b/arch/ppc/kernel/Makefile index 8276c0b551d2..b1457a8a9c0f 100644 --- a/arch/ppc/kernel/Makefile +++ b/arch/ppc/kernel/Makefile @@ -29,6 +29,7 @@ obj-$(CONFIG_ALTIVEC) += vecemu.o vector.o ifndef CONFIG_E200 obj-$(CONFIG_FSL_BOOKE) += perfmon_fsl_booke.o endif +obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o ifndef CONFIG_MATH_EMULATION obj-$(CONFIG_8xx) += softemu8xx.o diff --git a/arch/ppc/kernel/machine_kexec.c b/arch/ppc/kernel/machine_kexec.c new file mode 100644 index 000000000000..435ad9ea0a83 --- /dev/null +++ b/arch/ppc/kernel/machine_kexec.c @@ -0,0 +1,122 @@ +/* + * machine_kexec.c - handle transition of Linux booting another kernel + * Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com> + * + * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#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/hw_irq.h> +#include <asm/cacheflush.h> +#include <asm/machdep.h> + +typedef NORET_TYPE void (*relocate_new_kernel_t)( + unsigned long indirection_page, unsigned long reboot_code_buffer, + unsigned long start_address) ATTRIB_NORET; + +const extern unsigned char relocate_new_kernel[]; +const extern unsigned int relocate_new_kernel_size; + +void machine_shutdown(void) +{ + if (ppc_md.machine_shutdown) { + ppc_md.machine_shutdown(); + } +} + +void machine_crash_shutdown(void) +{ + if (ppc_md.machine_crash_shutdown) { + ppc_md.machine_crash_shutdown(); + } +} + +/* + * Do what every setup is needed on image and the + * reboot code buffer to allow us to avoid allocations + * later. + */ +int machine_kexec_prepare(struct kimage *image) +{ + if (ppc_md.machine_kexec_prepare) { + return ppc_md.machine_kexec_prepare(image); + } + /* + * Fail if platform doesn't provide its own machine_kexec_prepare + * implementation. + */ + return -ENOSYS; +} + +void machine_kexec_cleanup(struct kimage *image) +{ + if (ppc_md.machine_kexec_cleanup) { + ppc_md.machine_kexec_cleanup(image); + } +} + +/* + * Do not allocate memory (or fail in any way) in machine_kexec(). + * We are past the point of no return, committed to rebooting now. + */ +NORET_TYPE void machine_kexec(struct kimage *image) +{ + if (ppc_md.machine_kexec) { + ppc_md.machine_kexec(image); + } else { + /* + * Fall back to normal restart if platform doesn't provide + * its own kexec function, and user insist to kexec... + */ + machine_restart(NULL); + } + for(;;); +} + + +/* + * This is a generic machine_kexec function suitable at least for + * non-OpenFirmware embedded platforms. + * It merely copies the image relocation code to the control page and + * jumps to it. + * A platform specific function may just call this one. + */ +void machine_kexec_simple(struct kimage *image) +{ + unsigned long page_list; + unsigned long reboot_code_buffer, reboot_code_buffer_phys; + relocate_new_kernel_t rnk; + + /* Interrupts aren't acceptable while we reboot */ + local_irq_disable(); + + page_list = image->head; + + /* we need both effective and real address here */ + reboot_code_buffer = + (unsigned long)page_address(image->control_code_page); + reboot_code_buffer_phys = virt_to_phys((void *)reboot_code_buffer); + + /* copy our kernel relocation code to the control code page */ + memcpy((void *)reboot_code_buffer, + relocate_new_kernel, relocate_new_kernel_size); + + flush_icache_range(reboot_code_buffer, + reboot_code_buffer + KEXEC_CONTROL_CODE_SIZE); + printk(KERN_INFO "Bye!\n"); + + /* now call it */ + rnk = (relocate_new_kernel_t) reboot_code_buffer; + (*rnk)(page_list, reboot_code_buffer_phys, image->start); +} + diff --git a/arch/ppc/kernel/misc.S b/arch/ppc/kernel/misc.S index a3132f8e799c..b6a63a49a232 100644 --- a/arch/ppc/kernel/misc.S +++ b/arch/ppc/kernel/misc.S @@ -1444,7 +1444,7 @@ _GLOBAL(sys_call_table) .long sys_mq_timedreceive /* 265 */ .long sys_mq_notify .long sys_mq_getsetattr - .long sys_ni_syscall /* 268 reserved for sys_kexec_load */ + .long sys_kexec_load .long sys_add_key .long sys_request_key /* 270 */ .long sys_keyctl diff --git a/arch/ppc/kernel/relocate_kernel.S b/arch/ppc/kernel/relocate_kernel.S new file mode 100644 index 000000000000..7ff69c4af920 --- /dev/null +++ b/arch/ppc/kernel/relocate_kernel.S @@ -0,0 +1,123 @@ +/* + * relocate_kernel.S - put the kernel image in place to boot + * Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com> + * + * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#include <asm/reg.h> +#include <asm/ppc_asm.h> +#include <asm/processor.h> + +#include <asm/kexec.h> + +#define PAGE_SIZE 4096 /* must be same value as in <asm/page.h> */ + + /* + * Must be relocatable PIC code callable as a C function. + */ + .globl relocate_new_kernel +relocate_new_kernel: + /* r3 = page_list */ + /* r4 = reboot_code_buffer */ + /* r5 = start_address */ + + li r0, 0 + + /* + * Set Machine Status Register to a known status, + * switch the MMU off and jump to 1: in a single step. + */ + + mr r8, r0 + ori r8, r8, MSR_RI|MSR_ME + mtspr SRR1, r8 + addi r8, r4, 1f - relocate_new_kernel + mtspr SRR0, r8 + sync + rfi + +1: + /* from this point address translation is turned off */ + /* and interrupts are disabled */ + + /* set a new stack at the bottom of our page... */ + /* (not really needed now) */ + addi r1, r4, KEXEC_CONTROL_CODE_SIZE - 8 /* for LR Save+Back Chain */ + stw r0, 0(r1) + + /* Do the copies */ + li r6, 0 /* checksum */ + mr r0, r3 + b 1f + +0: /* top, read another word for the indirection page */ + lwzu r0, 4(r3) + +1: + /* is it a destination page? (r8) */ + rlwinm. r7, r0, 0, 31, 31 /* IND_DESTINATION (1<<0) */ + beq 2f + + rlwinm r8, r0, 0, 0, 19 /* clear kexec flags, page align */ + b 0b + +2: /* is it an indirection page? (r3) */ + rlwinm. r7, r0, 0, 30, 30 /* IND_INDIRECTION (1<<1) */ + beq 2f + + rlwinm r3, r0, 0, 0, 19 /* clear kexec flags, page align */ + subi r3, r3, 4 + b 0b + +2: /* are we done? */ + rlwinm. r7, r0, 0, 29, 29 /* IND_DONE (1<<2) */ + beq 2f + b 3f + +2: /* is it a source page? (r9) */ + rlwinm. r7, r0, 0, 28, 28 /* IND_SOURCE (1<<3) */ + beq 0b + + rlwinm r9, r0, 0, 0, 19 /* clear kexec flags, page align */ + + li r7, PAGE_SIZE / 4 + mtctr r7 + subi r9, r9, 4 + subi r8, r8, 4 +9: + lwzu r0, 4(r9) /* do the copy */ + xor r6, r6, r0 + stwu r0, 4(r8) + dcbst 0, r8 + sync + icbi 0, r8 + bdnz 9b + + addi r9, r9, 4 + addi r8, r8, 4 + b 0b + +3: + + /* To be certain of avoiding problems with self-modifying code + * execute a serializing instruction here. + */ + isync + sync + + /* jump to the entry point, usually the setup routine */ + mtlr r5 + blrl + +1: b 1b + +relocate_new_kernel_end: + + .globl relocate_new_kernel_size +relocate_new_kernel_size: + .long relocate_new_kernel_end - relocate_new_kernel + diff --git a/include/asm-ppc/kexec.h b/include/asm-ppc/kexec.h new file mode 100644 index 000000000000..73191310d8db --- /dev/null +++ b/include/asm-ppc/kexec.h @@ -0,0 +1,38 @@ +#ifndef _PPC_KEXEC_H +#define _PPC_KEXEC_H + +#ifdef CONFIG_KEXEC + +/* + * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return. + * I.e. Maximum page that is mapped directly into kernel memory, + * and kmap is not required. + * + * Someone correct me if FIXADDR_START - PAGEOFFSET is not the correct + * calculation for the amount of memory directly mappable into the + * kernel memory space. + */ + +/* Maximum physical address we can use pages from */ +#define KEXEC_SOURCE_MEMORY_LIMIT (-1UL) +/* Maximum address we can reach in physical address mode */ +#define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL) +/* Maximum address we can use for the control code buffer */ +#define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE + +#define KEXEC_CONTROL_CODE_SIZE 4096 + +/* The native architecture */ +#define KEXEC_ARCH KEXEC_ARCH_PPC + +#ifndef __ASSEMBLY__ + +struct kimage; + +extern void machine_kexec_simple(struct kimage *image); + +#endif /* __ASSEMBLY__ */ + +#endif /* CONFIG_KEXEC */ + +#endif /* _PPC_KEXEC_H */ diff --git a/include/asm-ppc/machdep.h b/include/asm-ppc/machdep.h index b78d40870c95..1d4ab70a56f3 100644 --- a/include/asm-ppc/machdep.h +++ b/include/asm-ppc/machdep.h @@ -4,6 +4,7 @@ #include <linux/config.h> #include <linux/init.h> +#include <linux/kexec.h> #include <asm/setup.h> #include <asm/page.h> @@ -114,6 +115,36 @@ struct machdep_calls { /* functions for dealing with other cpus */ struct smp_ops_t *smp_ops; #endif /* CONFIG_SMP */ + +#ifdef CONFIG_KEXEC + /* Called to shutdown machine specific hardware not already controlled + * by other drivers. + * XXX Should we move this one out of kexec scope? + */ + void (*machine_shutdown)(void); + + /* Called to do the minimal shutdown needed to run a kexec'd kernel + * to run successfully. + * XXX Should we move this one out of kexec scope? + */ + void (*machine_crash_shutdown)(void); + + /* Called to do what every setup is needed on image and the + * reboot code buffer. Returns 0 on success. + * Provide your own (maybe dummy) implementation if your platform + * claims to support kexec. + */ + int (*machine_kexec_prepare)(struct kimage *image); + + /* Called to handle any machine specific cleanup on image */ + void (*machine_kexec_cleanup)(struct kimage *image); + + /* Called to perform the _real_ kexec. + * Do NOT allocate memory or fail here. We are past the point of + * no return. + */ + void (*machine_kexec)(struct kimage *image); +#endif /* CONFIG_KEXEC */ }; extern struct machdep_calls ppc_md; |