u-boot-brain/arch/arm/cpu
Fabio Estevam 76c91e668a mx6: Disable Power Down Bit of watchdog
On a mx6qsabresd revision C board with rev1.2 mx6q, the system gets resetted
and it is not able to reach the Linux prompt.

Comparing the watchdog behaviour on a revB versus revC board:

- On a mx6qsabresd revB:

U-Boot > reset
resetting ...

U-Boot 2013.01-10524-g432a3aa-dirty (Feb 07 2013 - 13:34:46)

CPU:   Freescale i.MX6Q rev1.1 at 792 MHz
Reset cause: WDOG
...

- On a mx6qsabresd revC:

U-Boot > reset
resetting ...

U-Boot 2013.01-10524-g432a3aa-dirty (Feb 07 2013 - 13:34:46)

CPU:   Freescale i.MX6Q rev1.1 at 792 MHz
Reset cause: POR

So due to revC POR/watchdog circuitry whenever a watchdog occurs, it causes a POR.

Clearing the PDE - Power Down Enable bit of WMCR registers fixes the problem and
is also safe for all mx6 boards.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Otavio Salvador <otavio@ossystems.com.br>
Acked-by: Stefano Babic <sbabic@denx.de>
2013-02-12 13:54:34 +01:00
..
arm720t arm: move C runtime setup code in crt0.S 2013-01-08 22:14:50 +01:00
arm920t arm: move C runtime setup code in crt0.S 2013-01-08 22:14:50 +01:00
arm925t arm: remove useless code in start.S files 2013-01-08 22:14:54 +01:00
arm926ejs mxs: Use __weak annotation to simplify code 2013-01-28 06:54:19 +01:00
arm946es arm: move C runtime setup code in crt0.S 2013-01-08 22:14:50 +01:00
arm1136 Merge branch 'u-boot-imx/master' into 'u-boot-arm/master' 2013-01-14 17:00:02 +01:00
arm1176 arm: move C runtime setup code in crt0.S 2013-01-08 22:14:50 +01:00
arm_intcm arm: move C runtime setup code in crt0.S 2013-01-08 22:14:50 +01:00
armv7 mx6: Disable Power Down Bit of watchdog 2013-02-12 13:54:34 +01:00
ixp arm: move C runtime setup code in crt0.S 2013-01-08 22:14:50 +01:00
pxa pxa: Save lr register in relocate_code function 2013-01-14 16:22:00 -07:00
s3c44b0 arm: move C runtime setup code in crt0.S 2013-01-08 22:14:50 +01:00
sa1100 arm: move C runtime setup code in crt0.S 2013-01-08 22:14:50 +01:00
tegra20-common tegra: Add display support to funcmux 2012-11-19 08:15:35 -07:00
tegra-common tegra: clean up board include hell 2012-10-15 11:54:07 -07:00
u-boot.lds ARM: enhance u-boot.lds to detect over-sized SPL 2012-10-29 09:07:05 -07:00