2005-04-16 18:20:36 -04:00
|
|
|
/*
|
|
|
|
* arch/cris/boot/compressed/head.S
|
|
|
|
*
|
|
|
|
* Copyright (C) 1999, 2001 Axis Communications AB
|
|
|
|
*
|
|
|
|
* Code that sets up the DRAM registers, calls the
|
|
|
|
* decompressor to unpack the piggybacked kernel, and jumps.
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/config.h>
|
|
|
|
#define ASSEMBLER_MACROS_ONLY
|
|
|
|
#include <asm/arch/sv_addr_ag.h>
|
|
|
|
|
|
|
|
#define RAM_INIT_MAGIC 0x56902387
|
2005-07-27 14:44:38 -04:00
|
|
|
#define COMMAND_LINE_MAGIC 0x87109563
|
|
|
|
|
2005-04-16 18:20:36 -04:00
|
|
|
;; Exported symbols
|
|
|
|
|
|
|
|
.globl _input_data
|
|
|
|
|
|
|
|
|
|
|
|
.text
|
|
|
|
|
|
|
|
nop
|
|
|
|
di
|
|
|
|
|
|
|
|
;; We need to initialze DRAM registers before we start using the DRAM
|
|
|
|
|
|
|
|
cmp.d RAM_INIT_MAGIC, r8 ; Already initialized?
|
|
|
|
beq dram_init_finished
|
|
|
|
nop
|
|
|
|
|
|
|
|
#include "../../lib/dram_init.S"
|
|
|
|
|
|
|
|
dram_init_finished:
|
|
|
|
|
|
|
|
;; Initiate the PA and PB ports
|
|
|
|
|
|
|
|
move.b CONFIG_ETRAX_DEF_R_PORT_PA_DATA, r0
|
|
|
|
move.b r0, [R_PORT_PA_DATA]
|
|
|
|
|
|
|
|
move.b CONFIG_ETRAX_DEF_R_PORT_PA_DIR, r0
|
|
|
|
move.b r0, [R_PORT_PA_DIR]
|
|
|
|
|
|
|
|
move.b CONFIG_ETRAX_DEF_R_PORT_PB_DATA, r0
|
|
|
|
move.b r0, [R_PORT_PB_DATA]
|
|
|
|
|
|
|
|
move.b CONFIG_ETRAX_DEF_R_PORT_PB_DIR, r0
|
|
|
|
move.b r0, [R_PORT_PB_DIR]
|
|
|
|
|
|
|
|
;; Setup the stack to a suitably high address.
|
|
|
|
;; We assume 8 MB is the minimum DRAM in an eLinux
|
|
|
|
;; product and put the sp at the top for now.
|
|
|
|
|
|
|
|
move.d 0x40800000, sp
|
|
|
|
|
|
|
|
;; Figure out where the compressed piggyback image is
|
|
|
|
;; in the flash (since we wont try to copy it to DRAM
|
|
|
|
;; before unpacking). It is at _edata, but in flash.
|
|
|
|
;; Use (_edata - basse) as offset to the current PC.
|
|
|
|
|
|
|
|
basse: move.d pc, r5
|
|
|
|
and.d 0x7fffffff, r5 ; strip any non-cache bit
|
|
|
|
subq 2, r5 ; compensate for the move.d pc instr
|
|
|
|
move.d r5, r0 ; save for later - flash address of 'basse'
|
|
|
|
add.d _edata, r5
|
|
|
|
sub.d basse, r5 ; r5 = flash address of '_edata'
|
|
|
|
|
|
|
|
;; Copy text+data to DRAM
|
|
|
|
|
|
|
|
move.d basse, r1 ; destination
|
|
|
|
move.d _edata, r2 ; end destination
|
|
|
|
1: move.w [r0+], r3
|
|
|
|
move.w r3, [r1+]
|
|
|
|
cmp.d r2, r1
|
|
|
|
bcs 1b
|
|
|
|
nop
|
|
|
|
|
|
|
|
move.d r5, [_input_data] ; for the decompressor
|
|
|
|
|
|
|
|
|
|
|
|
;; Clear the decompressors BSS (between _edata and _end)
|
|
|
|
|
|
|
|
moveq 0, r0
|
|
|
|
move.d _edata, r1
|
|
|
|
move.d _end, r2
|
|
|
|
1: move.w r0, [r1+]
|
|
|
|
cmp.d r2, r1
|
|
|
|
bcs 1b
|
|
|
|
nop
|
2005-07-27 14:44:38 -04:00
|
|
|
|
|
|
|
;; Save command line magic and address.
|
|
|
|
move.d _cmd_line_magic, $r12
|
|
|
|
move.d $r10, [$r12]
|
|
|
|
move.d _cmd_line_addr, $r12
|
|
|
|
move.d $r11, [$r12]
|
2005-04-16 18:20:36 -04:00
|
|
|
|
|
|
|
;; Do the decompression and save compressed size in _inptr
|
|
|
|
|
|
|
|
jsr _decompress_kernel
|
|
|
|
|
|
|
|
;; Put start address of root partition in r9 so the kernel can use it
|
|
|
|
;; when mounting from flash
|
|
|
|
|
|
|
|
move.d [_input_data], r9 ; flash address of compressed kernel
|
|
|
|
add.d [_inptr], r9 ; size of compressed kernel
|
2005-07-27 14:44:38 -04:00
|
|
|
|
|
|
|
;; Restore command line magic and address.
|
|
|
|
move.d _cmd_line_magic, $r10
|
|
|
|
move.d [$r10], $r10
|
|
|
|
move.d _cmd_line_addr, $r11
|
|
|
|
move.d [$r11], $r11
|
|
|
|
|
2005-04-16 18:20:36 -04:00
|
|
|
;; Enter the decompressed kernel
|
|
|
|
move.d RAM_INIT_MAGIC, r8 ; Tell kernel that DRAM is initialized
|
|
|
|
jump 0x40004000 ; kernel is linked to this address
|
|
|
|
|
|
|
|
.data
|
|
|
|
|
|
|
|
_input_data:
|
|
|
|
.dword 0 ; used by the decompressor
|
2005-07-27 14:44:38 -04:00
|
|
|
_cmd_line_magic:
|
|
|
|
.dword 0
|
|
|
|
_cmd_line_addr:
|
|
|
|
.dword 0
|
2005-04-16 18:20:36 -04:00
|
|
|
#include "../../lib/hw_settings.S"
|