u-boot/cpu/arm926ejs/davinci/reset.S
Thomas Lange 2ae0f35fd6 ARM DaVinci: Reset with watchdog enabled
Once the Davinci watchdog has been enabled, the timeout
value cannot be changed. If the timeout in use is long,
it can take a long time for card to reset. By writing
an invalid service key, we can trigger an immediate reset.

Signed-off-by: Thomas Lange <thomas@corelatus.se>
2009-06-12 20:39:51 +02:00

81 lines
1.8 KiB
ArmAsm

/*
* Processor reset using WDT for TI TMS320DM644x SoC.
*
* Copyright (C) 2007 Sergey Kubushyn <ksi@koi8.net>
*
* -----------------------------------------------------
*
* This program 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 2 of
* the License, or (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
.globl reset_cpu
reset_cpu:
ldr r0, WDT_TGCR
mov r1, $0x08
str r1, [r0]
ldr r1, [r0]
orr r1, r1, $0x03
str r1, [r0]
mov r1, $0
ldr r0, WDT_TIM12
str r1, [r0]
ldr r0, WDT_TIM34
str r1, [r0]
ldr r0, WDT_PRD12
str r1, [r0]
ldr r0, WDT_PRD34
str r1, [r0]
ldr r0, WDT_TCR
ldr r1, [r0]
orr r1, r1, $0x40
str r1, [r0]
ldr r0, WDT_WDTCR
ldr r1, [r0]
orr r1, r1, $0x4000
str r1, [r0]
ldr r1, WDTCR_VAL1
str r1, [r0]
ldr r1, WDTCR_VAL2
str r1, [r0]
/* Write an invalid value to the WDKEY field to trigger
* an immediate watchdog reset */
mov r1, $0x4000
str r1, [r0]
nop
nop
nop
nop
reset_cpu_loop:
b reset_cpu_loop
WDT_TGCR:
.word 0x01c21c24
WDT_TIM12:
.word 0x01c21c10
WDT_TIM34:
.word 0x01c21c14
WDT_PRD12:
.word 0x01c21c18
WDT_PRD34:
.word 0x01c21c1c
WDT_TCR:
.word 0x01c21c20
WDT_WDTCR:
.word 0x01c21c28
WDTCR_VAL1:
.word 0xa5c64000
WDTCR_VAL2:
.word 0xda7e4000