Erratum 71 of PXA270M Processor Family Specification Update
(April 19, 2010) explains that watchdog reset time is just
8us insead of 10ms in EMTS.
If SDRAM is not reset, it causes memory bus congestion and
the device hangs. We put SDRAM in selfresh mode before watchdog
reset, removing potential freezes.
Without this patch PXA270-based ICP DAS LP-8x4x hangs after up to 40
reboots. With this patch it has successfully rebooted 500 times.
Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
Tested-by: Marek Vasut <marex@denx.de>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Olof Johansson <olof@lixom.net>
This chip has a control register and can prevent altering saved clock.
Without this patch we could have:
(arm)root@pac14:~# date
Tue May 21 03:08:27 MSK 2013
(arm)root@pac14:~# /etc/init.d/hwclock.sh show
Tue May 21 11:13:58 2013 -0.067322 seconds
(arm)root@pac14:~# /etc/init.d/hwclock.sh stop
[info] Saving the system clock.
[info] Hardware Clock updated to Tue May 21 03:09:01 MSK 2013.
(arm)root@pac14:~# /etc/init.d/hwclock.sh show
Tue May 21 11:14:15 2013 -0.624272 seconds
The patch enables write access to rtc before the driver tries to write
time and re-disables when time data is written.
Signed-off-by: Sergey Yanovich <ynvich@gmail.com>
Acked-by: Marc Zyngier <maz@misterjones.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
MMC hosts are added asynchronously. We need to wait until detect returns to
avoid failed root filesystem mounts.
VFS: Cannot open root device "mmcblk0p1" or unknown-block(0,0): error -6
Please append a correct "root=" boot option; here are the available partitions:
mmc0: host does not support reading read-only switch. assuming write-enable.
1f00 256 mtdblock0 (driver?)
1f01 256 mtdblock1 (driver?)
1f02 2560 mtdblock2 mmc0: new SDHC card at address b368
(driver?)
1f03 29696 mtdblock3 (driver?)
1f04 16384 mtdblock4 mmcblk0: mmc0:b368 USD 3.72 GiB
(driver?)
mmcblk0: p1
b300 3910656 mmcblk0 driver: mmcblk
b301 3906560 mmcblk0p1 00000000-01
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
Signed-off-by: Sergey Yanovich <ynvich@gmail.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Sergei Ianovich