Commit graph

1036 commits

Author SHA1 Message Date
Marc van der Wal 0bcd0b6a47 watchdog: it87_wdt: Work around non-working CIR interrupts
On some hardware platforms, the it87_wdt watchdog resets the machine
despite the watchdog daemon running and writing to /dev/watchdog.

This is due to Consumer IR buffer underrun interrupts being used as
triggers to reset the timer.  On some buggy hardware implementations
such as the iEi AFL-12A-N270 single-board computer, this method does
not work.

However, resetting the timer by writing its original timeout value in
its configuration register over and over again suppresses the unwanted
reboots.

Add a module option (nocir), 0 by default in order not to break existing
setups.  Setting it to 1 enables the workaround.

Fixes bug #42801 <https://bugzilla.kernel.org/show_bug.cgi?id=42801>.
Tested primarily on Linux 3.5.7, applies cleanly on Linux 3.13.5.

Signed-off-by: Marc van der Wal <x0r+kernel@x0r.fr>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:33:55 +02:00
Markus Mayer 5e82ec94ac watchdog: bcm281xx: Fix Kconfig dependency
Use more the applicable ARCH_BCM_MOBILE option instead of ARCH_BCM as
dependency for bcm_kona_wdt.c.

Signed-off-by: Markus Mayer <markus.mayer@linaro.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:33:36 +02:00
Sachin Kamat 01b6af9159 watchdog: s3c2410_wdt: Check return value of clk_prepare_enable
clk_prepare_enable can fail. Check its return value.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:33:16 +02:00
Sachin Kamat a94dd879e2 watchdog: s3c2410_wdt: Remove unneeded initialization
Initializing clk to NULL as a reset/error condition does not
help as NULL is not an invalid condition w.r.t clk. Remove this
initialization altogether as there is no state retention.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:32:34 +02:00
Maxime Ripard b0f1d8bec7 watchdog: sunxi: Change compatibles
The Allwinner A10 and A31 compatibles were following a slightly different
compatible patterns than the rest of the SoCs for historical reasons. Change
the compatibles to match the other pattern in the watchdog controller driver
for consistency.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:32:03 +02:00
Sebastian Hesselbarth 0187cca30c watchdog: orion: prepare new Dove DT Kconfig variable
DT-enabled Dove will move over from ARCH_DOVE in mach-dove to MACH_DOVE in
mach-mvebu. As non-DT ARCH_DOVE will stay to rot for a while, add a new
DT-only MACH_DOVE Kconfig.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:31:37 +02:00
Jingoo Han 5f5e19093b watchdog: fix checkpatch warnings and error
Fix the following checkpatch warnings and error:
  WARNING: quoted string split across lines
  WARNING: braces {} are not necessary for single statement blocks
  WARNING: __initdata should be placed after ibmasr_id_table[]
  WARNING: please, no space before tabs
  ERROR: do not initialise statics to 0 or NULL

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:31:06 +02:00
Andrew Chew c33a15974c watchdog: Add tegra watchdog
Add a driver for the hardware watchdogs in NVIDIA Tegra SoCs (Tegra30 and
later).  This driver will configure one watchdog timer that will reset the
system in the case of a watchdog timeout.

This driver binds to the nvidia,tegra30-timer device node and gets its
register base from there.

Signed-off-by: Andrew Chew <achew@nvidia.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:30:29 +02:00
Michal Simek 8d6a140b5f watchdog: xilinx: Remove no_timeout variable
Remove no_timeout variable and check variables
directly.

Suggested-by: Rob Herring <robherring2@gmail.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:29:31 +02:00
Michal Simek c9dcf9f2ea watchdog: xilinx: Enable this driver for Zynq
Enable this driver for Zynq.
Move it to architecture independent Kconfig part.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:29:28 +02:00
Michal Simek 75b3c5a827 watchdog: xilinx: Use correct comment indentation
No functional changes.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:29:21 +02:00
Michal Simek 2e79a36847 watchdog: xilinx: Use of_property_read_u32
Use of_property_read_u32 functions to clean probe function.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:29:18 +02:00
Michal Simek 4c7fbbc4a5 watchdog: xilinx: Fix all printk messages
Use dev_ functions for printk messages.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:29:14 +02:00
Michal Simek 9066317178 watchdog: xilinx: Allocate private structure per device
Only one watchdog could be used by this driver.
Create driver private data structure and move there
all variables for one instance.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:29:11 +02:00
Michal Simek ffb8eee4f1 watchdog: xilinx: Move no_timeout to probe function
no_timeout should be local variable because it is used
only in probe function.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:29:08 +02:00
Michal Simek f06cdfd184 watchdog: xilinx: Simplify probe and remove functions
Use devm_ helper function to simplify probe and error path.
Move ioremap to the beginning of probe function.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:29:04 +02:00
Michal Simek 5cf4e69d39 watchdog: xilinx: Move control_status_reg to functions
control_status_reg is temp variables and should be
used locally by specific function.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:29:00 +02:00
Michal Simek d14fd96455 watchdog: xilinx: Convert driver to the watchdog framework
- Remove uneeded headers, fops functions
- Use xilinx_wdt prefix in start/stop/keepalive functions
  and in new structures

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:28:56 +02:00
Alexander Shiyan 70605d9bab watchdog: wdt285: Fix variable type
Variable "new_margin" is checked in the function watchdog_ioctl()
to be non-negative, so change its type to "int".

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:28:20 +02:00
Alexander Shiyan 1cf8a3487d watchdog: shwdt: Remove unused variable
Variable "wdt" is not used anywhere in the function sh_wdt_remove().
This patch removes this variable.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:28:00 +02:00
Alexander Shiyan a9ba8376e9 watchdog: sc520_wdt: Remove unused variable
Variable "dummy" is not used anywhere in the function wdt_config().
This patch removes this variable.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:27:34 +02:00
Alexander Shiyan c303ca8765 watchdog: intel_scu_watchdog: Remove unused variable
Variable "hw_pre_value" is not used anywhere in the
function intel_scu_set_heartbeat().
This patch removes this variable.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:26:56 +02:00
Alexander Shiyan 0c29c2e850 watchdog: indydog: Simplify indydog_{start,stop}
This patch simplify functions indydog_start() and indydog_stop()
a bit and removes excess intermediate variable.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:26:31 +02:00
Alexander Shiyan 7bce7c011e watchdog: bcm63xx_wdt: Remove unused field from bcm63xx_wdt_device
Field "default_ticks" is not used anywhere in the driver code.
This patch removes this field.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:26:04 +02:00
Jingoo Han 9d11e4f8c3 watchdog: sp805_wdt: Use devm_ioremap_resource()
Use devm_ioremap_resource() in order to make the code simpler.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:24:57 +02:00
Jingoo Han 6e27206139 watchdog: omap_wdt: Use devm_ioremap_resource()
Use devm_ioremap_resource() in order to make the code simpler,
and remove 'struct resource *mem' from 'struct omap_wdt_dev'
and omap_wdt_probe(), resplectively. because the 'mem' variables
are not used anymore. Also the redundant return value check of
platform_get_resource() is removed, because the value is checked
by devm_ioremap_resource().

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:24:31 +02:00
Jingoo Han 4f6120b014 watchdog: ep93xx_wdt: Use devm_ioremap_resource()
Use devm_ioremap_resource() in order to make the code simpler,
and remove redundant return value check of platform_get_resource()
because the value is checked by devm_ioremap_resource().

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:24:14 +02:00
Jingoo Han a17fb5cbee watchdog: ts72xx_wdt: make 'ts72xx_wdt_pdev' static
Make 'ts72xx_wdt_pdev' static, because it is used only in this
file. It also fixes the following sparse warning.

  warning: symbol 'ts72xx_wdt_pdev' was not declared. Should it be static?

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:23:46 +02:00
Jingoo Han 8deea83064 watchdog: Remove unnecessary OOM messages
The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message. For example,
k.alloc and v.alloc failures use dump_stack().

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de> [for at32ap700x]
Acked-by: Lubomir Rintel <lkundrak@v3.sk> [for bcm2835]
Acked-by: Viresh Kumar <viresh.kumar@linaro.org> [for sp805_wdt]
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> [for ts72xx_wdt]
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:23:19 +02:00
Paul Gortmaker 8126334b20 watchdog: delete non-required instances of include <linux/init.h>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: linux-watchdog@vger.kernel.org
2014-03-31 13:22:45 +02:00
Christophe Leroy 4af897fa99 watchdog: mpc8xxx_wdt: MPC8xx is HW enabled
MPC8xx watchdog is enabled at startup by HW.
If the bootloader disables it, it cannot be reenabled.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:21:33 +02:00
Stanislav Kholmanskikh 0cb1c3e853 watchdog: w83697hf_wdt: return ENODEV if no device was found
Most WDT driver modules return ENODEV during modprobe if
no valid device was found, but w83697hf_wdt returns EIO.

Let w83697hf_wdt return ENODEV.

Signed-off-by: Stanislav Kholmanskikh <stanislav.kholmanskikh@oracle.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-02-21 20:36:46 +01:00
Richard Weinberger 1ccfe6f982 watchdog: dw_wdt: Add dependency on HAS_IOMEM
On archs like S390 or um this driver cannot build nor work.
Make it depend on HAS_IOMEM to bypass build failures.

drivers/built-in.o: In function `dw_wdt_drv_probe':
drivers/watchdog/dw_wdt.c:302: undefined reference to `devm_ioremap_resource'

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-02-08 09:47:11 +01:00
Guenter Roeck ea3d4011a8 watchdog: w83627hf_wdt: Reset watchdog trigger during initialization
If the watchdog has already triggered for whatever reason, it won't restart
unless the trigger is reset.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:35:40 +01:00
Guenter Roeck 7b6d0b6ad4 watchdog: w83627hf: Add support for W83697HF and W83697UG
Major difference is that the watchdog control and counter registers
are different on both chips.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:35:37 +01:00
Guenter Roeck 962c04f54e watchdog: w83627hf: Auto-detect IO address and supported chips
Instead of requiring the user to provide an IO address per module
parameter, auto-detect it as well as supported chips.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:35:30 +01:00
Boris BREZILLON f72fa00f8a watchdog: at91sam9_wdt: increase security margin on watchdog counter reset
Try to reset the watchdog counter 4 or 2 times more often than actually
requested, to avoid spurious watchdog reset.
If this is not possible because of the min_heartbeat value, reset it at
the min_heartbeat period.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:34:55 +01:00
Boris BREZILLON a04c3f01d3 watchdog: at91sam9_wdt: avoid spurious watchdog reset during init
Use the min_heartbeat value instead of the calculated heartbeat value for
the first watchdog reset to avoid spurious watchdog reset.

Resetting the watchdog counter during init might lead to a watchdog fault
reset because the watchdog counter has to be running for at least
min_heartbeat.

Resetting the watchdog counter after heartbeat might lead to a watchdog
timeout reset because the watchdog counter is running for more than
max_heartbeat time.

Using min_heartbeat instead of heartbeat does not guarantee that the
watchdog won't trigger a reset, but at least it reduces the chances to be
in such a case.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:34:38 +01:00
Boris BREZILLON 1444797fc1 watchdog: at91sam9_wdt: fix secs_to_ticks
Fix the secs_to_ticks macro in case 0 is passed as an argument.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:34:18 +01:00
Boris BREZILLON 5161b31dc3 watchdog: at91sam9_wdt: better watchdog support
The at91sam9 watchdog timer can only be configured once, and the current
implementation tries to configure it in a static way:
- 2 seconds timeout
- wdt restart every 500ms

If the timer has already been configured with different values, it returns an
error and do not create any watchdog device.

This is not critical if the watchdog is disabled, but if it has been enabled with
different timeout values it will lead to a SoC reset.

This patch series tries to address this issue by adapting the heartbeat value
according the WDT timer config:
- it first tries to configure the timer as requested.
- if it fails it fallbacks to the current config, adapting its heartbeat timer
to the needs

This patch series also move to a dynamically allocated at91wdt device instead
of the static instance.

It adds a new at91 wdt type: software. This new type make use of the at91 wdt
interrupt to trigger a software reboot.

Finally it adds several properties to the device tree bindings.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:28:37 +01:00
Naresh Bhat e30722e497 watchdog: sp805_wdt depends also on ARM64
Add sp805_wdt depends on ARM64.

Signed-off-by: Naresh Bhat <naresh.bhat@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:27:52 +01:00
Jonas Jensen 8773926d71 watchdog: mach-moxart: add restart handler
mach-moxart lacks a separate register for reset; as a workaround,
add a function that can be hooked to arm_pm_restart.

Signed-off-by: Jonas Jensen <jonas.jensen@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:27:32 +01:00
Christophe Leroy d5cfaf0a85 watchdog: mpc8xxx_wdt convert to watchdog core
Convert mpc8xxx_wdt.c to the new watchdog API.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:27:08 +01:00
Sachin Kamat 15edd9eedd watchdog: sirf: Remove redundant of_match_ptr helper
'sirfsoc_wdt_of_match' is always compiled in. Hence the
helper macro is not needed.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:26:31 +01:00
Thomas Mingarelli 7bb5be947e watchdog: hpwdt patch to display informative string
This patch is being submitted to output a general string when the panic comes
in that informs the user of the possible places to look for the source of the
NMI. Because various systems log the message in different places this would
give a single display of where to go look instead of code that acts on all
these different server names or IDs.

Signed-off-by: Thomas Mingarelli <thomas.mingarelli@hp.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:26:10 +01:00
Baruch Siach 58a251f2c2 watchdog: dw_wdt: remove build dependencies
There is nothing ARM specific in this driver, and we intend to use it on the
Xtensa architecture. Also, clk.h now includes stubs for !CONFIG_HAVE_CLK, so
the driver should build anyway.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:25:46 +01:00
Anson Huang 1a9c5efa57 watchdog: imx2_wdt: disable watchdog timer during low power mode
We should set watchdog timer to be disabled in low power mode,
as there is no service running in background, otherwise, system
will reset unexpected.

Signed-off-by: Anson Huang <b20788@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:25:20 +01:00
Doug Anderson cffc9a60eb watchdog: s3c2410_wdt: Report when the watchdog reset the system
A good watchdog driver is supposed to report when it was responsible
for resetting the system.  Implement this for the s3c2410, at least on
exynos5250 and exynos5420 where we already have a pointer to the PMU
registers to read the information.

Note that exynos4 SoCs also provide the reset status, but providing
that is left as an exercise for future changes and is not plumbed up
in this patch series.  Also note the exynos4 SoCs don't appear to need
any PMU config, which is why this patch separates the concepts of
having PMU Registers vs. needing PMU Config.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:24:33 +01:00
Leela Krishna Amudala 4f1f653a68 watchdog: s3c2410_wdt: use syscon regmap interface to configure pmu register
Add device tree support for exynos5250 and 5420 SoCs and use syscon regmap interface
to configure AUTOMATIC_WDT_RESET_DISABLE and MASK_WDT_RESET_REQUEST registers of PMU
to mask/unmask enable/disable of watchdog in probe and s2r scenarios.

Signed-off-by: Leela Krishna Amudala <l.krishna@samsung.com>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:24:15 +01:00
Doug Anderson 178624403c watchdog: s3c2410_wdt: Handle rounding a little better for timeout
The existing watchdog timeout worked OK but didn't deal with
rounding in an ideal way when dividing out all of its clocks.

Specifically if you had a timeout of 32 seconds and an input clock of
66666666, you'd end up setting a timeout of 31.9998 seconds and
reporting a timeout of 31 seconds.

Specifically DBG printouts showed:
  s3c2410wdt_set_heartbeat: count=16666656, timeout=32, freq=520833
  s3c2410wdt_set_heartbeat: timeout=32, divisor=255, count=16666656 (0000ff4f)
and the final timeout reported to the user was:
  ((count / divisor) * divisor) / freq
  (0xff4f * 255) / 520833 = 31 (truncated from 31.9998)
the technically "correct" value is:
  (0xff4f * 255) / (66666666.0 / 128) = 31.9998

By using "DIV_ROUND_UP" we can be a little more correct.
  s3c2410wdt_set_heartbeat: count=16666688, timeout=32, freq=520834
  s3c2410wdt_set_heartbeat: timeout=32, divisor=255, count=16666688 (0000ff50)
and the final timeout reported to the user:
  (0xff50 * 255) / 520834 = 32
the technically "correct" value is:
  (0xff50 * 255) / (66666666.0 / 128) = 32.0003

We'll use a DIV_ROUND_UP to solve this, generally erroring on the side
of reporting shorter values to the user and setting the watchdog to
slightly longer than requested:
* Round input frequency up to assume watchdog is counting faster.
* Round divisions by divisor up to give us extra time.

At the same time we can avoid a for loop by just doing the right math.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:23:20 +01:00