OpenWrt – Rev 1
?pathlinks?
/*
* Kernel relocation stub for MIPS devices
*
* Copyright (C) 2015 Felix Fietkau <nbd@nbd.name>
*
* Based on:
*
* LZMA compressed kernel loader for Atheros AR7XXX/AR9XXX based boards
*
* Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
*
* Some parts of this code was based on the OpenWrt specific lzma-loader
* for the BCM47xx and ADM5120 based boards:
* Copyright (C) 2004 Manuel Novoa III (mjn3@codepoet.org)
* Copyright (C) 2005 by Oleg I. Vdovikin <oleg@cs.msu.su>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*/
#include <asm/asm.h>
#include <asm/regdef.h>
#include "cp0regdef.h"
#include "cacheops.h"
#define KSEG0 0x80000000
.macro ehb
sll zero, 3
.endm
.macro reset
li t0, 0xbe000034
lw t1, 0(t0)
ori t1, 1
sw t1, 0(t0)
.endm
.text
LEAF(startup)
.set noreorder
.set mips32
.fill 0x10000
mtc0 zero, CP0_WATCHLO # clear watch registers
mtc0 zero, CP0_WATCHHI
mtc0 zero, CP0_CAUSE # clear before writing status register
mfc0 t0, CP0_STATUS
li t1, 0x1000001f
or t0, t1
xori t0, 0x1f
mtc0 t0, CP0_STATUS
ehb
mtc0 zero, CP0_COUNT
mtc0 zero, CP0_COMPARE
ehb
la t0, __reloc_label # get linked address of label
bal __reloc_label # branch and link to label to
nop # get actual address
__reloc_label:
subu t0, ra, t0 # get reloc_delta
/* Copy our code to the right place */
la t1, _code_start # get linked address of _code_start
la t2, _code_end # get linked address of _code_end
addu t4, t2, t0 # calculate actual address of _code_end
lw t5, 0(t4) # get extra data size
add t2, t5
add t2, 4
add t0, t1 # calculate actual address of _code_start
__reloc_copy:
lw t3, 0(t0)
sw t3, 0(t1)
add t1, 4
blt t1, t2, __reloc_copy
add t0, 4
/* flush cache */
la t0, _code_start
la t1, _code_end
li t2, ~(CONFIG_CACHELINE_SIZE - 1)
and t0, t2
and t1, t2
li t2, CONFIG_CACHELINE_SIZE
b __flush_check
nop
__flush_line:
cache Hit_Writeback_Inv_D, 0(t0)
cache Hit_Invalidate_I, 0(t0)
add t0, t2
__flush_check:
bne t0, t1, __flush_line
nop
sync
la t0, __reloc_back
j t0
nop
__reloc_back:
la t0, _code_end
add t0, 4
addu t1, t0, t5
li t2, KERNEL_ADDR
__kernel_copy:
lw t3, 0(t0)
sw t3, 0(t2)
add t0, 4
blt t0, t1, __kernel_copy
add t2, 4
/* flush cache */
li t0, KERNEL_ADDR
addu t1, t0, t5
add t1, CONFIG_CACHELINE_SIZE - 1
li t2, ~(CONFIG_CACHELINE_SIZE - 1)
and t0, t2
and t1, t2
li t2, CONFIG_CACHELINE_SIZE
b __kernel_flush_check
nop
__kernel_flush_line:
cache Hit_Writeback_Inv_D, 0(t0)
cache Hit_Invalidate_I, 0(t0)
add t0, t2
__kernel_flush_check:
bne t0, t1, __kernel_flush_line
nop
sync
li t0, KERNEL_ADDR
jr t0
nop
.set reorder
END(startup)