grub/grub-core/boot/mips/startup_raw.S
2010-09-21 19:39:51 +02:00

186 lines
3.8 KiB
ArmAsm

/* startup.S - Startup code for the MIPS. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2009 Free Software Foundation, Inc.
*
* GRUB 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 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/symbol.h>
#include <grub/offsets.h>
#include <grub/machine/memory.h>
#include <grub/offsets.h>
#define BASE_ADDR 8
.extern __bss_start
.extern _end
.globl __start, _start, start
.set noreorder
.set nomacro
__start:
_start:
start:
bal codestart
nop
base:
. = _start + GRUB_KERNEL_MACHINE_COMPRESSED_SIZE
compressed_size:
.long 0
. = _start + GRUB_KERNEL_MACHINE_UNCOMPRESSED_SIZE
uncompressed_size:
.long 0
codestart:
/* Save our base. */
move $s0, $ra
/* Parse arguments. Has to be done before relocation.
So need to do it in asm. */
#ifdef GRUB_MACHINE_MIPS_YEELOONG
move $s2, $zero
move $s3, $zero
move $s4, $zero
move $s5, $zero
/* $a2 has the environment. */
addiu $t0, $a2, 1
beq $t0, $zero, argdone
nop
move $t0, $a2
argcont:
lw $t1, 0($t0)
beq $t1, $zero, argdone
nop
#define DO_PARSE(str, reg) \
addiu $t2, $s0, (str-base);\
bal parsestr;\
beq $v0, $zero, 1f;\
nop ;\
b 2f;\
move reg, $v0;
1:
DO_PARSE (busclockstr, $s2)
DO_PARSE (cpuclockstr, $s3)
DO_PARSE (memsizestr, $s4)
DO_PARSE (highmemsizestr, $s5)
2:
b argcont
addiu $t0, $t0, 4
parsestr:
move $v0, $zero
move $t3, $t1
3:
lb $t4, 0($t2)
lb $t5, 0($t3)
addiu $t2, $t2, 1
addiu $t3, $t3, 1
beq $t5, $zero, 1f
nop
beq $t5, $t4, 3b
nop
bne $t4, $zero, 1f
nop
addiu $t3, $t3, 0xffff
digcont:
lb $t5, 0($t3)
/* Substract '0' from digit. */
addiu $t5, $t5, 0xffd0
bltz $t5, 1f
nop
addiu $t4, $t5, 0xfff7
bgtz $t4, 1f
nop
/* Multiply $v0 by 10 with bitshifts. */
sll $v0, $v0, 1
sll $t4, $v0, 2
addu $v0, $v0, $t4
addu $v0, $v0, $t5
addiu $t3, $t3, 1
b digcont
nop
1:
jr $ra
nop
busclockstr: .asciiz "busclock="
cpuclockstr: .asciiz "cpuclock="
memsizestr: .asciiz "memsize="
highmemsizestr: .asciiz "highmemsize="
.p2align 2
argdone:
#endif
/* Copy the decompressor. */
lui $t1, %hi(base)
addiu $t1, $t1, %lo(base)
lui $t3, %hi(__bss_start)
addiu $t3, $t3, %lo(__bss_start)
move $t2, $s0
1:
beq $t1, $t3, 2f
lb $t4, 0($t2)
sb $t4, 0($t1)
addiu $t1, $t1, 1
b 1b
addiu $t2, $t2, 1
2:
/* Clean out its BSS. */
lui $t1, %hi(__bss_start)
addiu $t1, $t1, %lo(__bss_start)
lui $t2, %hi(_end)
addiu $t2, $t2, %lo(_end)
1:
beq $t1, $t2, 2f
nop
sb $zero, 0($t1)
b 1b
addiu $t1, $t1, 1
2:
/* Decompress the payload. */
lui $a0, %hi(__bss_start)
addiu $a0, $a0, %lo(__bss_start)
lui $t0, %hi(base)
addiu $t0, $t0, %lo(base)
subu $a0, $a0, $t0
addu $a0, $a0, $s0
lui $a1, %hi(GRUB_MACHINE_LINK_ADDR)
addiu $a1, %lo(GRUB_MACHINE_LINK_ADDR)
lw $a2, (GRUB_KERNEL_MACHINE_COMPRESSED_SIZE - BASE_ADDR)($s0)
lw $a3, (GRUB_KERNEL_MACHINE_UNCOMPRESSED_SIZE - BASE_ADDR)($s0)
move $s1, $a1
/* $a0 contains source compressed address, $a1 is destination,
$a2 is compressed size, $a3 is uncompressed size.
*/
move $s6, $a3
lui $sp, %hi(_start)
bal EXT_C(grub_decompress_core)
addiu $sp, $sp, %lo(_start)
move $a0, $s1
move $a1, $s6
#include "../../kern/mips/cache_flush.S"
lui $t1, %hi(GRUB_MACHINE_LINK_ADDR)
addiu $t1, %lo(GRUB_MACHINE_LINK_ADDR)
jr $t1
nop