From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Wed, 11 Apr 2007 03:34:11 -0500 (CDT) Subject: [PATCH 8/8] bootwrapper: example sreset marshalling Sender: From: Milton Miller To: linuxppc-dev@ozlabs.org Message-Id: In-Reply-To: Cc: Paul Mackerras , David Gibson List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , An example that uses the marshalling code but expects cpus to be sreset. This reuses the kexec code after finding the device tree (which is magically available at 31K by whatever means loaded this code). With the marshalling code is at 0 in the image and the checks in platform_init, it also works as a kexec target when left as elf. --- Status: works with sreset on the tested platform when image data loaded at 0 and the device tree loaded at 31MB. Works as kexec called elf image from 64 bit kernel with kexec-supplied device-tree and initrd. The attached device-tree and initrd cases have not been tested. Index: kernel/arch/powerpc/boot/crt0_bml.S =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ kernel/arch/powerpc/boot/crt0_bml.S 2007-04-09 05:12:35.000000000 -0500 @@ -0,0 +1,73 @@ +/* + * Copyright (C) 2006-2007 Milton Miller, IBM Corporation. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + /* + * This can be either a kexec started image or a sreset initiated + * one. kexec-tools purgatory is suppposed to copy from entry + * point, but instead copies from image start, so put marshal_low + * at address 0. + */ + + .globl zImage_start +zImage_start: +#include "marshal_low.S" + + .org 0x100 + bl get_cpu_id +1: mflr 0 + lis r4,1b@ha + addi r4,r4,1b@l + subf r0,r4,r0 + + lis r4,elected_master@ha + addi r4,r4,elected_master@l + add r4,r4,r0 +2: lwarx r6,r0,r4 + cmpwi r6,0 + bge 3f + stwcx. r3,r0,r4 + bne- 2b + lwz r6,0(r4) + +3: lis r4,cpus_found@ha + addi r4,r4,cpus_found@l + add r4,r4,r0 +4: lwarx r12,r0,r4 + addi r12,r12,1 + stwcx. r12,r0,r4 + bne- 4b + + cmpw r6,r3 + bne slave + + mr r4,r0 + li r5,0 + b master + + + .globl _zimage_start_plat +_zimage_start_plat: + b _zimage_start_32_64 + + .weak get_cpu_id +get_cpu_id: + +get_pir: + mfspr r3,1023 /* SPRN_PIR */ + blr + + .balign 8 + .globl elected_master +elected_master: + .long -1 + .globl cpus_expected +cpus_expected: + .long 8 + .globl cpus_found +cpus_found: + .long 0 Index: kernel/arch/powerpc/boot/bml.c =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ kernel/arch/powerpc/boot/bml.c 2007-04-09 04:17:24.000000000 -0500 @@ -0,0 +1,42 @@ +#include "ops.h" +#include "reg.h" +#include "flatdevtree.h" + +extern struct boot_param_header _dtb_start[], _dtb_end[]; +struct boot_param_header *bml_dt_blob; + +extern unsigned int get_cpu_id(void); +extern unsigned int cpus_found, cpus_expected; + +void platform_init(unsigned long boot_cpu_id) +{ + if (boot_cpu_id > 1024) { + bml_dt_blob = (void *)boot_cpu_id; + boot_cpu_id = get_cpu_id(); + } + + if (!bml_dt_blob) + if (_dtb_start != _dtb_end) + bml_dt_blob = _dtb_start; + + if (!bml_dt_blob) + bml_dt_blob = 31 * 1024 * 1024 + (void *)0; + + if (bml_dt_blob->magic != OF_DT_HEADER) + fatal("No device tree at %p\n", bml_dt_blob); + + if (bml_dt_blob->version < 2) + conv_flattree_inplace(bml_dt_blob); + + bml_dt_blob->boot_cpuid_phys = boot_cpu_id; + + if (cpus_found && cpus_found < cpus_expected) { + HMT_LOW; + while (cpus_found < cpus_expected) { + barrier(); + } + HMT_MEDIUM; + } + + kexec_platform_init(bml_dt_blob); +} Index: kernel/arch/powerpc/boot/Makefile =================================================================== --- kernel.orig/arch/powerpc/boot/Makefile 2007-04-09 04:17:10.000000000 -0500 +++ kernel/arch/powerpc/boot/Makefile 2007-04-09 04:17:24.000000000 -0500 @@ -46,6 +46,7 @@ src-wlib := string.S crt0.S stdio.c main gunzip_util.c $(zlib) kexec.c rtas.c src-plat := of.c src-plat += crt0_kexec.S +src-plat += crt0_bml.S bml.c src-boot := $(src-wlib) $(src-plat) empty.c src-boot := $(addprefix $(obj)/, $(src-boot)) @@ -124,7 +125,7 @@ quiet_cmd_wrap = WRAP $@ $(if $3, -s $3)$(if $4, -d $4)$(if $5, -i $5) vmlinux kexec-$(CONFIG_PPC32) += zImage.kexec -kexec-$(CONFIG_PPC64) += zImage.kexec64 +kexec-$(CONFIG_PPC64) += zImage.kexec64 zImage.bml image-$(CONFIG_PPC_PSERIES) += zImage.pseries image-$(CONFIG_PPC_MAPLE) += zImage.pseries Index: kernel/arch/powerpc/boot/wrapper =================================================================== --- kernel.orig/arch/powerpc/boot/wrapper 2007-04-09 04:17:10.000000000 -0500 +++ kernel/arch/powerpc/boot/wrapper 2007-04-09 04:17:24.000000000 -0500 @@ -139,6 +139,9 @@ kexec) kexec64) platformo="-e _zimage_start64 $object/crt0_kexec.o" ;; +bml) + platformo="$object/crt0_bml.o $object/bml.o" + ;; miboot|uboot) # miboot and U-boot want just the bare bits, not an ELF binary ext=bin