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> 131a1cf93cSHari Bathini#include <asm/crashdump-ppc64.h> 1419031275SHari Bathini 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 461a1cf93cSHari Bathini /* Work out where we're running */ 471a1cf93cSHari Bathini bcl 20, 31, 0f 481a1cf93cSHari Bathini0: mflr %r18 491a1cf93cSHari Bathini 501a1cf93cSHari Bathini /* 511a1cf93cSHari Bathini * Copy BACKUP_SRC_SIZE bytes from BACKUP_SRC_START to 521a1cf93cSHari Bathini * backup_start 8 bytes at a time. 531a1cf93cSHari Bathini * 541a1cf93cSHari Bathini * Use r3 = dest, r4 = src, r5 = size, r6 = count 551a1cf93cSHari Bathini */ 561a1cf93cSHari Bathini ld %r3, (backup_start - 0b)(%r18) 571a1cf93cSHari Bathini cmpdi %cr0, %r3, 0 581a1cf93cSHari Bathini beq .Lskip_copy /* skip if there is no backup region */ 591a1cf93cSHari Bathini lis %r5, BACKUP_SRC_SIZE@h 601a1cf93cSHari Bathini ori %r5, %r5, BACKUP_SRC_SIZE@l 611a1cf93cSHari Bathini cmpdi %cr0, %r5, 0 621a1cf93cSHari Bathini beq .Lskip_copy /* skip if copy size is zero */ 631a1cf93cSHari Bathini lis %r4, BACKUP_SRC_START@h 641a1cf93cSHari Bathini ori %r4, %r4, BACKUP_SRC_START@l 651a1cf93cSHari Bathini li %r6, 0 661a1cf93cSHari Bathini.Lcopy_loop: 671a1cf93cSHari Bathini ldx %r0, %r6, %r4 681a1cf93cSHari Bathini stdx %r0, %r6, %r3 691a1cf93cSHari Bathini addi %r6, %r6, 8 701a1cf93cSHari Bathini cmpld %cr0, %r6, %r5 711a1cf93cSHari Bathini blt .Lcopy_loop 721a1cf93cSHari Bathini 731a1cf93cSHari Bathini.Lskip_copy: 7419031275SHari Bathini or %r3,%r3,%r3 /* ok now to high priority, lets boot */ 7519031275SHari Bathini lis %r6,0x1 7619031275SHari Bathini mtctr %r6 /* delay a bit for slaves to catch up */ 7719031275SHari Bathini bdnz . /* before we overwrite 0-100 again */ 7819031275SHari Bathini 7919031275SHari Bathini /* load device-tree address */ 8019031275SHari Bathini ld %r3, (dt_offset - 0b)(%r18) 8119031275SHari Bathini mr %r16,%r3 /* save dt address in reg16 */ 8219031275SHari Bathini li %r4,20 8319031275SHari Bathini LWZX_BE %r6,%r3,%r4 /* fetch __be32 version number at byte 20 */ 8419031275SHari Bathini cmpwi %cr0,%r6,2 /* v2 or later? */ 8519031275SHari Bathini blt 1f 8619031275SHari Bathini li %r4,28 8719031275SHari Bathini STWX_BE %r17,%r3,%r4 /* Store my cpu as __be32 at byte 28 */ 8819031275SHari Bathini1: 892e6bd221SHari Bathini /* Load opal base and entry values in r8 & r9 respectively */ 902e6bd221SHari Bathini ld %r8,(opal_base - 0b)(%r18) 912e6bd221SHari Bathini ld %r9,(opal_entry - 0b)(%r18) 922e6bd221SHari Bathini 9319031275SHari Bathini /* load the kernel address */ 9419031275SHari Bathini ld %r4,(kernel - 0b)(%r18) 9519031275SHari Bathini 9619031275SHari Bathini /* load the run_at_load flag */ 9719031275SHari Bathini /* possibly patched by kexec */ 9819031275SHari Bathini ld %r6,(run_at_load - 0b)(%r18) 9919031275SHari Bathini /* and patch it into the kernel */ 10019031275SHari Bathini stw %r6,(0x5c)(%r4) 10119031275SHari Bathini 10219031275SHari Bathini mr %r3,%r16 /* restore dt address */ 10319031275SHari Bathini 10419031275SHari Bathini li %r5,0 /* r5 will be 0 for kernel */ 10519031275SHari Bathini 10619031275SHari Bathini mfmsr %r11 10719031275SHari Bathini andi. %r10,%r11,1 /* test MSR_LE */ 10819031275SHari Bathini bne .Little_endian 10919031275SHari Bathini 11019031275SHari Bathini mtctr %r4 /* prepare branch to */ 11119031275SHari Bathini bctr /* start kernel */ 11219031275SHari Bathini 11319031275SHari Bathini.Little_endian: 11419031275SHari Bathini mtsrr0 %r4 /* prepare branch to */ 11519031275SHari Bathini 11619031275SHari Bathini clrrdi %r11,%r11,1 /* clear MSR_LE */ 11719031275SHari Bathini mtsrr1 %r11 11819031275SHari Bathini 11919031275SHari Bathini rfid /* update MSR and start kernel */ 12019031275SHari Bathini 12119031275SHari Bathini .balign 8 12219031275SHari Bathini .globl kernel 12319031275SHari Bathinikernel: 12419031275SHari Bathini .8byte 0x0 12519031275SHari Bathini .size kernel, . - kernel 12619031275SHari Bathini 12719031275SHari Bathini .balign 8 12819031275SHari Bathini .globl dt_offset 12919031275SHari Bathinidt_offset: 13019031275SHari Bathini .8byte 0x0 13119031275SHari Bathini .size dt_offset, . - dt_offset 13219031275SHari Bathini 1331a1cf93cSHari Bathini .balign 8 1341a1cf93cSHari Bathini .globl backup_start 1351a1cf93cSHari Bathinibackup_start: 1361a1cf93cSHari Bathini .8byte 0x0 1371a1cf93cSHari Bathini .size backup_start, . - backup_start 13819031275SHari Bathini 1392e6bd221SHari Bathini .balign 8 1402e6bd221SHari Bathini .globl opal_base 1412e6bd221SHari Bathiniopal_base: 1422e6bd221SHari Bathini .8byte 0x0 1432e6bd221SHari Bathini .size opal_base, . - opal_base 1442e6bd221SHari Bathini 1452e6bd221SHari Bathini .balign 8 1462e6bd221SHari Bathini .globl opal_entry 1472e6bd221SHari Bathiniopal_entry: 1482e6bd221SHari Bathini .8byte 0x0 1492e6bd221SHari Bathini .size opal_entry, . - opal_entry 1502e6bd221SHari Bathini 15119031275SHari Bathini .data 15219031275SHari Bathini .balign 8 15319031275SHari Bathini.globl purgatory_sha256_digest 15419031275SHari Bathinipurgatory_sha256_digest: 15519031275SHari Bathini .skip 32 15619031275SHari Bathini .size purgatory_sha256_digest, . - purgatory_sha256_digest 15719031275SHari Bathini 15819031275SHari Bathini .balign 8 15919031275SHari Bathini.globl purgatory_sha_regions 16019031275SHari Bathinipurgatory_sha_regions: 16119031275SHari Bathini .skip 8 * 2 * 16 16219031275SHari Bathini .size purgatory_sha_regions, . - purgatory_sha_regions 163