0,0 → 1,116 |
# |
# Copyright (c) 2006 Martin Decky |
# All rights reserved. |
# |
# Redistribution and use in source and binary forms, with or without |
# modification, are permitted provided that the following conditions |
# are met: |
# |
# - Redistributions of source code must retain the above copyright |
# notice, this list of conditions and the following disclaimer. |
# - Redistributions in binary form must reproduce the above copyright |
# notice, this list of conditions and the following disclaimer in the |
# documentation and/or other materials provided with the distribution. |
# - The name of the author may not be used to endorse or promote products |
# derived from this software without specific prior written permission. |
# |
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
# |
|
#include "regname.h" |
|
.set noat |
.set noreorder |
.set nomacro |
|
.text |
|
.global halt |
.global memcpy |
.global jump_to_kernel |
|
halt: |
b halt |
nop |
|
memcpy: |
addiu $v0,$a1,3 |
li $v1,-4 # 0xfffffffffffffffc |
and $v0,$v0,$v1 |
beq $a1,$v0,3f |
move $t0,$a0 |
move $t2,$a0 # save dst |
|
0: |
beq $a2,$zero,2f |
move $a3,$zero |
|
1: |
addu $v0,$a1,$a3 |
lbu $a0,0($v0) |
addu $v1,$t0,$a3 |
addiu $a3,$a3,1 |
bne $a3,$a2,1b |
sb $a0,0($v1) |
|
2: |
jr $ra |
move $v0,$t2 |
|
3: |
addiu $v0,$a0,3 |
and $v0,$v0,$v1 |
bne $a0,$v0,0b |
srl $t1,$a2,2 |
|
beq $t1,$zero,5f |
move $a3,$zero |
|
move $a3,$zero |
move $a0,$zero |
4: |
addu $v0,$a1,$a0 |
lw $v1,0($v0) |
addiu $a3,$a3,1 |
addu $v0,$t0,$a0 |
sw $v1,0($v0) |
bne $a3,$t1,4b |
addiu $a0,$a0,4 |
|
5: |
andi $a2,$a2,0x3 |
beq $a2,$zero,2b |
nop |
|
sll $v0,$a3,2 |
addu $t1,$v0,$t0 |
move $a3,$zero |
addu $t0,$v0,$a1 |
6: |
addu $v0,$t0,$a3 |
lbu $a0,0($v0) |
addu $v1,$t1,$a3 |
addiu $a3,$a3,1 |
bne $a3,$a2,6b |
sb $a0,0($v1) |
|
jr $ra |
move $v0,$t2 |
|
jump_to_kernel: |
# |
# TODO |
# Make sure that the I-cache, D-cache and memory are mutually coherent |
# before passing control to the copied code. |
# |
j $a0 |
nop |