119031275SHari Bathini/* SPDX-License-Identifier: GPL-2.0-only */ 219031275SHari Bathini/* 319031275SHari Bathini * kexec trampoline 419031275SHari Bathini * 519031275SHari Bathini * Based on code taken from kexec-tools and kexec-lite. 619031275SHari Bathini * 719031275SHari Bathini * Copyright (C) 2004 - 2005, Milton D Miller II, IBM Corporation 819031275SHari Bathini * Copyright (C) 2006, Mohan Kumar M, IBM Corporation 919031275SHari Bathini * Copyright (C) 2013, Anton Blanchard, IBM Corporation 1019031275SHari Bathini */ 1119031275SHari Bathini 1219031275SHari Bathini#include <asm/asm-compat.h> 1319031275SHari Bathini 1419031275SHari Bathini .machine ppc64 1519031275SHari Bathini .balign 256 1619031275SHari Bathini .globl purgatory_start 1719031275SHari Bathinipurgatory_start: 1819031275SHari Bathini b master 1919031275SHari Bathini 2019031275SHari Bathini /* ABI: possible run_at_load flag at 0x5c */ 2119031275SHari Bathini .org purgatory_start + 0x5c 2219031275SHari Bathini .globl run_at_load 2319031275SHari Bathinirun_at_load: 2419031275SHari Bathini .long 0 2519031275SHari Bathini .size run_at_load, . - run_at_load 2619031275SHari Bathini 2719031275SHari Bathini /* ABI: slaves start at 60 with r3=phys */ 2819031275SHari Bathini .org purgatory_start + 0x60 2919031275SHari Bathinislave: 3019031275SHari Bathini b . 3119031275SHari Bathini /* ABI: end of copied region */ 3219031275SHari Bathini .org purgatory_start + 0x100 3319031275SHari Bathini .size purgatory_start, . - purgatory_start 3419031275SHari Bathini 3519031275SHari Bathini/* 3619031275SHari Bathini * The above 0x100 bytes at purgatory_start are replaced with the 3719031275SHari Bathini * code from the kernel (or next stage) by setup_purgatory(). 3819031275SHari Bathini */ 3919031275SHari Bathini 4019031275SHari Bathinimaster: 4119031275SHari Bathini or %r1,%r1,%r1 /* low priority to let other threads catchup */ 4219031275SHari Bathini isync 4319031275SHari Bathini mr %r17,%r3 /* save cpu id to r17 */ 4419031275SHari Bathini mr %r15,%r4 /* save physical address in reg15 */ 4519031275SHari Bathini 4619031275SHari Bathini or %r3,%r3,%r3 /* ok now to high priority, lets boot */ 4719031275SHari Bathini lis %r6,0x1 4819031275SHari Bathini mtctr %r6 /* delay a bit for slaves to catch up */ 4919031275SHari Bathini bdnz . /* before we overwrite 0-100 again */ 5019031275SHari Bathini 5119031275SHari Bathini bl 0f /* Work out where we're running */ 5219031275SHari Bathini0: mflr %r18 5319031275SHari Bathini 5419031275SHari Bathini /* load device-tree address */ 5519031275SHari Bathini ld %r3, (dt_offset - 0b)(%r18) 5619031275SHari Bathini mr %r16,%r3 /* save dt address in reg16 */ 5719031275SHari Bathini li %r4,20 5819031275SHari Bathini LWZX_BE %r6,%r3,%r4 /* fetch __be32 version number at byte 20 */ 5919031275SHari Bathini cmpwi %cr0,%r6,2 /* v2 or later? */ 6019031275SHari Bathini blt 1f 6119031275SHari Bathini li %r4,28 6219031275SHari Bathini STWX_BE %r17,%r3,%r4 /* Store my cpu as __be32 at byte 28 */ 6319031275SHari Bathini1: 6419031275SHari Bathini /* load the kernel address */ 6519031275SHari Bathini ld %r4,(kernel - 0b)(%r18) 6619031275SHari Bathini 6719031275SHari Bathini /* load the run_at_load flag */ 6819031275SHari Bathini /* possibly patched by kexec */ 6919031275SHari Bathini ld %r6,(run_at_load - 0b)(%r18) 7019031275SHari Bathini /* and patch it into the kernel */ 7119031275SHari Bathini stw %r6,(0x5c)(%r4) 7219031275SHari Bathini 7319031275SHari Bathini mr %r3,%r16 /* restore dt address */ 7419031275SHari Bathini 7519031275SHari Bathini li %r5,0 /* r5 will be 0 for kernel */ 7619031275SHari Bathini 7719031275SHari Bathini mfmsr %r11 7819031275SHari Bathini andi. %r10,%r11,1 /* test MSR_LE */ 7919031275SHari Bathini bne .Little_endian 8019031275SHari Bathini 8119031275SHari Bathini mtctr %r4 /* prepare branch to */ 8219031275SHari Bathini bctr /* start kernel */ 8319031275SHari Bathini 8419031275SHari Bathini.Little_endian: 8519031275SHari Bathini mtsrr0 %r4 /* prepare branch to */ 8619031275SHari Bathini 8719031275SHari Bathini clrrdi %r11,%r11,1 /* clear MSR_LE */ 8819031275SHari Bathini mtsrr1 %r11 8919031275SHari Bathini 9019031275SHari Bathini rfid /* update MSR and start kernel */ 9119031275SHari Bathini 9219031275SHari Bathini 9319031275SHari Bathini .balign 8 9419031275SHari Bathini .globl kernel 9519031275SHari Bathinikernel: 9619031275SHari Bathini .8byte 0x0 9719031275SHari Bathini .size kernel, . - kernel 9819031275SHari Bathini 9919031275SHari Bathini .balign 8 10019031275SHari Bathini .globl dt_offset 10119031275SHari Bathinidt_offset: 10219031275SHari Bathini .8byte 0x0 10319031275SHari Bathini .size dt_offset, . - dt_offset 10419031275SHari Bathini 10519031275SHari Bathini 10619031275SHari Bathini .data 10719031275SHari Bathini .balign 8 10819031275SHari Bathini.globl purgatory_sha256_digest 10919031275SHari Bathinipurgatory_sha256_digest: 11019031275SHari Bathini .skip 32 11119031275SHari Bathini .size purgatory_sha256_digest, . - purgatory_sha256_digest 11219031275SHari Bathini 11319031275SHari Bathini .balign 8 11419031275SHari Bathini.globl purgatory_sha_regions 11519031275SHari Bathinipurgatory_sha_regions: 11619031275SHari Bathini .skip 8 * 2 * 16 11719031275SHari Bathini .size purgatory_sha_regions, . - purgatory_sha_regions 118