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microwatt/tests/branch_alias/head.S

211 lines
3.6 KiB
ArmAsm

/* Copyright 2013-2014 IBM Corp.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* Load an immediate 64-bit value into a register */
#define LOAD_IMM64(r, e) \
lis r,(e)@highest; \
ori r,r,(e)@higher; \
rldicr r,r, 32, 31; \
oris r,r, (e)@h; \
ori r,r, (e)@l;
.section ".head","ax"
/*
* Microwatt currently enters in LE mode at 0x0, so we don't need to
* do any endian fix ups
*/
. = 0
.global _start
_start:
LOAD_IMM64(%r10,__bss_start)
LOAD_IMM64(%r11,__bss_end)
subf %r11,%r10,%r11
addi %r11,%r11,63
srdi. %r11,%r11,6
beq 2f
mtctr %r11
1: dcbz 0,%r10
addi %r10,%r10,64
bdnz 1b
2: LOAD_IMM64(%r1,__stack_top)
li %r0,0
stdu %r0,-16(%r1)
mtsprg2 %r0
LOAD_IMM64(%r12, main)
mtctr %r12
bctrl
attn // terminate on exit
b .
#define EXCEPTION(nr) \
.= nr; \
b .
EXCEPTION(0x300)
EXCEPTION(0x380)
. = 0x400
b call_ret
EXCEPTION(0x480)
EXCEPTION(0x500)
EXCEPTION(0x600)
EXCEPTION(0x700)
EXCEPTION(0x800)
EXCEPTION(0x900)
EXCEPTION(0x980)
EXCEPTION(0xa00)
EXCEPTION(0xb00)
. = 0xc00
nop
nop
nop
nop
b 1f
nop
1: rfid
EXCEPTION(0xd00)
EXCEPTION(0xe00)
EXCEPTION(0xe20)
EXCEPTION(0xe40)
EXCEPTION(0xe60)
EXCEPTION(0xe80)
EXCEPTION(0xf00)
EXCEPTION(0xf20)
EXCEPTION(0xf40)
EXCEPTION(0xf60)
EXCEPTION(0xf80)
. = 0x1000
/*
* This page gets mapped at virtual address 0
*/
.globl test_code
test_code:
b 1f
. = 0x1c00
1: nop
nop
nop
nop
li %r3,1
li %r3,0
// Exit via 0x400 exception
ba -4
.globl test_code_end
test_code_end:
. = 0x2000
/*
* Call a function in a context with a given MSR value.
* r3, r4 = args; r5 = function; r6 = MSR
*/
.globl callit
callit:
mflr %r0
std %r0,16(%r1)
stdu %r1,-256(%r1)
mfcr %r8
stw %r8,100(%r1)
std %r13,104(%r1)
std %r14,112(%r1)
std %r15,120(%r1)
std %r16,128(%r1)
std %r17,136(%r1)
std %r18,144(%r1)
std %r19,152(%r1)
std %r20,160(%r1)
std %r21,168(%r1)
std %r22,176(%r1)
std %r23,184(%r1)
std %r24,192(%r1)
std %r25,200(%r1)
std %r26,208(%r1)
std %r27,216(%r1)
std %r28,224(%r1)
std %r29,232(%r1)
std %r30,240(%r1)
std %r31,248(%r1)
li %r0,restore@l
mtsprg0 %r0
mtsprg1 %r1
mtsprg2 %r2
mfmsr %r9
mtsprg3 %r9
li %r10,call_ret@l
mtlr %r10
mtsrr0 %r5
mtsrr1 %r6
mr %r12,%r5
rfid
call_ret:
tdi 0,%r0,0x48 /* b .+8 if wrong endian */
b 2f /* if endian OK */
/* reverse-endian version of instructions from 2: on */
.long 0xa642107c
.long 0xa642937c
.long 0xa602ba7c
.long 0xa602db7c
.long 0xa643b07c
.long 0xa643d37c
.long 0xa6031a7c
.long 0xa6039b7c
.long 0x2400004c
2: mfsprg0 %r0
mfsprg3 %r4
mfsrr0 %r5
mfsrr1 %r6
mtsprg0 %r5
mtsprg3 %r6
mtsrr0 %r0
mtsrr1 %r4
rfid
restore:
mfsprg1 %r1
mfsprg2 %r2
li %r7,0
mtsprg2 %r7
lwz %r8,100(%r1)
mtcr %r8
ld %r13,104(%r1)
ld %r14,112(%r1)
ld %r15,120(%r1)
ld %r16,128(%r1)
ld %r17,136(%r1)
ld %r18,144(%r1)
ld %r19,152(%r1)
ld %r20,160(%r1)
ld %r21,168(%r1)
ld %r22,176(%r1)
ld %r23,184(%r1)
ld %r24,192(%r1)
ld %r25,200(%r1)
ld %r26,208(%r1)
ld %r27,216(%r1)
ld %r28,224(%r1)
ld %r29,232(%r1)
ld %r30,240(%r1)
ld %r31,248(%r1)
addi %r1,%r1,256
ld %r0,16(%r1)
mtlr %r0
blr