// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later /* * Test the SRESET OPAL call in Mambo by * having a bit of fun printing 'Hello World' from the SRESET vector. * * Copyright 2013-2017 IBM Corp. */ . = 0x0 .globl _start _start: /* * Save some values passed in from skiboot into registers that are * non-volatile over OPAL calls. * r8 is the OPAL base * r9 is the OPAL entry point point */ mr %r13, %r8 mr %r14, %r9 bl here here: mflr %r8 /* work out where we are running */ subi %r8, %r8, here - _start /* Stash OPAL base and entry point somewhere SRESET can find it */ li %r6, 0xe0 std %r13, 0(%r6) std %r14, 8(%r6) std %r8, 16(%r6) addi %r6, %r8, sreset_code_end - _start addi %r7, %r8, sreset_code - _start li %r10, 0x100 c: lwa %r9, 0(%r7) stw %r9, 0(%r10) addi %r7,%r7,4 addi %r10,%r10,4 cmpd %r7,%r6 bne c sync icbi 0,%r0 sync isync li %r0, 1 /* OPAL_CONSOLE_WRITE */ li %r3, 0 /* terminal 0 */ addi %r4, %r8, len - _start /* ptr to length of string */ addi %r5, %r8, str - _start /* ptr to string start */ mr %r2, %r13 mtctr %r14 bctrl li %r0, 145 /* OPAL_SIGNAL_SYSTEM_RESET */ li %r3, -2 /* All *OTHER* CPUs */ mr %r2, %r13 mtctr %r14 bctrl /* We shouldn't get here but if we do, just wait here */ b . sreset_code: li %r6, 0xe0 ld %r13, 0(%r6) ld %r14, 8(%r6) ld %r8, 16(%r6) /* "here" */ li %r0, 1 /* OPAL_CONSOLE_WRITE */ li %r3, 0 /* terminal 0 */ li %r4, len2 - _start li %r5, str2 - _start add %r4, %r8, %r4 add %r5, %r8, %r5 mr %r2, %r13 mtctr %r14 bctrl li %r0, 5 /* OPAL_CEC_POWER_DOWN */ li %r3, 0 /* normal shutdown */ mr %r2, %r13 mtctr %r14 bctrl /* We shouldn't get here but if we do, just wait here */ b . sreset_code_end: len: .long 0x00 .long (strend - str) str: .string "Hello World!\n" strend: len2: .long 0x00 .long (str2end - str2) str2: .string "Hello SRESET!\n" str2end: