The watchdog core can handle pinging of the watchdog before userspace
opens the device. For this reason instead of stopping the timer, just
mark it as running and let the watchdog core take care of it.
Cc: Malin Jonsson <malin.jonsson@ericsson.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210921102900.61586-1-mika.westerberg@linux.intel.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Use the devm_platform_ioremap_resource() helper instead of
calling platform_get_resource() and devm_ioremap_resource()
separately
Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210907074230.2757-1-caihuoqing@baidu.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
This reverts commit cb011044e3 ("watchdog: iTCO_wdt: Account for
rebooting on second timeout") and commit aec42642d9 ("watchdog: iTCO_wdt:
Fix detection of SMI-off case") since those patches cause a regression
on certain boards (https://bugzilla.kernel.org/show_bug.cgi?id=213809).
While this revert may result in some boards to only reset after twice
the configured timeout value, that is still better than a watchdog reset
after half the configured value.
Fixes: cb011044e3 ("watchdog: iTCO_wdt: Account for rebooting on second timeout")
Fixes: aec42642d9 ("watchdog: iTCO_wdt: Fix detection of SMI-off case")
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Mantas Mikulėnas <grawity@gmail.com>
Reported-by: Javier S. Pedro <debbugs@javispedro.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20211008003302.1461733-1-linux@roeck-us.net
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Obviously, the test needs to run against the register content, not its
address.
Fixes: cb011044e3 ("watchdog: iTCO_wdt: Account for rebooting on second timeout")
Cc: stable@vger.kernel.org
Reported-by: Mantas Mikulėnas <grawity@gmail.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Mantas Mikulėnas <grawity@gmail.com>
Link: https://lore.kernel.org/r/d84f8e06-f646-8b43-d063-fb11f4827044@siemens.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Use dev_err() instead of pr_err(), so device name is also shown in the log.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210616181708.19530-2-info@metux.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
This was already attempted to fix via 1fccb73011: If the BIOS did not
enable TCO SMIs, the timer definitely needs to trigger twice in order to
cause a reboot. If TCO SMIs are on, as well as SMIs in general, we can
continue to assume that the BIOS will perform a reboot on the first
timeout.
QEMU with its ICH9 and related BIOS falls into the former category,
currently taking twice the configured timeout in order to reboot the
machine. For iTCO version that fall under turn_SMI_watchdog_clear_off,
this is also true and was currently only addressed for v1, irrespective
of the turn_SMI_watchdog_clear_off value.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/0b8bb307-d08b-41b5-696c-305cdac6789c@siemens.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
For device log outputs, it's better to have device name / ID
prefixed in all messages, so use the proper dev_*() functions here.
Explicit message on module load/unload don't seem to be really helpful
(we have other means to check which modules have been loaded), instead
just add noise to the kernel log. So, removing them.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20201117152214.32244-2-info@metux.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
This driver only creates a bunch of platform devices sharing resources
belonging to the PMC device. This is pretty much what MFD subsystem is
for so move the driver there, renaming it to intel_pmc_bxt.c which
should be more clear what it is.
MFD subsystem provides nice helper APIs for subdevice creation so
convert the driver to use those. Unfortunately the ACPI device includes
separate resources for most of the subdevices so we cannot simply call
mfd_add_devices() to create all of them but instead we need to call it
separately for each device.
The new MFD driver continues to expose two sysfs attributes that allow
userspace to send IPC commands to the PMC/SCU to avoid breaking any
existing applications that may use these. Generally this is bad idea so
document this in the ABI documentation.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
The iTCO_wdt driver only needs ICH_RES_IO_SMI I/O resource when either
turn_SMI_watchdog_clear_off module parameter is set to match ->iTCO_version
(or higher), and when legacy iTCO_vendorsupport is set. Modify the driver
so that ICH_RES_IO_SMI is optional if the two conditions are not met.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In Intel Cannon Lake PCH the NO_REBOOT bit was moved from the private
register space to be part of the TCO1_CNT register. For this reason
introduce another version (6) that uses this register to set and clear
NO_REBOOT bit.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This gets rid of the unnecessary license boilerplate, and avoids
having to deal with individual patches one by one.
No functional changes.
Reviewed-by: Jerry Hoemann <jerry.hoemann@hpe.com>
Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Various coccinelle driven transformations as detailed below.
The conversion was done automatically with coccinelle using the
following semantic patches. The semantic patches and the scripts
used to generate this commit log are available at
https://github.com/groeck/coccinelle-patches
- Use watchdog_stop_on_unregister to stop the watchdog on remove
- Drop assignments to otherwise unused variables
- Drop empty remove function
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
As the only user of iTCO_vendor_pre_keepalive and
iTCO_vendor_pre_set_heartbeat has just been removed, we can delete
these 2 hooks.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Martin Wilck <mwilck@suse.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
This reverts commit 1fccb73011.
Reported as Bug 196509 - iTCO_wdt regression reboot before timeout expire
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
The ICH9 is listed as having TCO v2, and indeed the behavior in the
datasheet corresponds to v2 (for example the NO_REBOOT flag is
accessible via the 16KiB-aligned Root Complex Base Address).
However, the TCO counts twice just like in v1; the documentation
of the SECOND_TO_STS bit says: "ICH9 sets this bit to 1 to indicate
that the TIMEOUT bit had been (or is currently) set and a second
timeout occurred before the TCO_RLD register was written. If this
bit is set and the NO_REBOOT config bit is 0, then the ICH9 will
reboot the system after the second timeout. The same can be found
in the BayTrail (Atom E3800) datasheet, and even HOWTOs around
the Internet say that it will reboot after _twice_ the specified
heartbeat.
I did not find the Apollo Lake datasheet, but because v4/v5 has
a SECOND_TO_STS bit just like the previous version I'm enabling
this for Apollo Lake as well.
Cc: linux-watchdog@vger.kernel.org
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
In some SoCs, setting noreboot bit needs modification to
PMC GC registers. But not all PMC drivers allow other drivers
to memory map their GC region. This could create mem request
conflict in watchdog driver. So this patch adds facility to allow
PMC drivers to pass noreboot update function to watchdog
drivers via platform data.
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
iTCO_wdt no_reboot_bit set/unset functions has lot of common code between
them. So merging these two functions into a single update function would
remove these unnecessary code duplications. This patch fixes this issue
by creating a no_reboot_bit update function to handle both set/unset
functions.
Also checking for iTCO version every time you make no_reboot_bit set/unset
call is inefficient and makes the code look complex. This can be improved
by performing this check once during device probe and selecting the
appropriate no_reboot_bit update function. This patch fixes this issue
by splitting the update function into multiple helper functions.
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
The shutdown function calls the stop function.
Call watchdog_stop_on_reboot() from probe instead.
The conversion was done automatically with coccinelle using the
following semantic patches. The semantic patches and the scripts used
to generate this commit log are available at
https://github.com/groeck/coccinelle-patches
- Replace shutdown function with call to watchdog_stop_on_reboot()
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The 'ret' variable in iTCO_wdt_init_module() does not add any value;
drop it.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Use pdev for struct platform_device, pci_dev for struct pci_dev, and dev
for struct device variables to improve consistency.
Remove 'struct platform_device *dev;' from struct iTCO_wdt_private since
it was unused.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Using device managed resources simplifies error handling and cleanup,
and to reduce the likelyhood of errors.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Allocate private data and the watchdog device to avoid having
to clear it on remove and to enable subsequent simplifications.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
iTCO_wdt_pm, of type struct dev_pm_ops, is never modified, so declare it as
const.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
The Apollo Lake Watchdog has the no_reboot flag in the 4th bit.
Signed-off-by: Yong, Jonathan <jonathan.yong@intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
The revision of the watchdog hardware in Sunrisepoint necessitates a new
"version" inside the TCO watchdog driver because some of the register
layouts have changed.
Also update the Kconfig entry to select both the LPC and SMBus drivers
since the TCO device is on the SMBus in Sunrisepoint.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Intel Sunrisepoint (Skylake PCH) has the iTCO watchdog accessible across
the SMBus, unlike previous generations of PCH/ICH where it was on the
LPC bus. Because it's on the SMBus, it doesn't make sense to pass around
a 'struct lpc_ich_info', and leaking the type of bus into the iTCO
watchdog driver is kind of backwards anyway.
This change introduces a new 'struct itco_wdt_platform_data' for use
inside the iTCO watchdog driver and by the upcoming Intel Sunrisepoint
code, which neatly avoids having to include lpc_ich headers in the i801
i2c driver.
This change is overdue because lpc_ich_info has already found its way
into other TCO watchdog users, notably the intel_pmc_ipc driver where
the watchdog actually isn't on the LPC bus as far as I can see.
A simple translation layer is provided for converting from the existing
'struct lpc_ich_info' inside the lpc_ich mfd driver.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Acked-by: Darren Hart <dvhart@linux.intel.com> [drivers/x86 refactoring]
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
If the target sleep state of the system is not an ACPI sleep state
(S1, S2 or S3), the TCO watchdog needs to be stopped during system
suspend, because it may not be possible to ping it any more after
timekeeping has been suspended (suspend-to-idle does that for
one example).
For this reason, provide ->suspend_noirq and ->resume_noirq
callbacks for the iTCO watchdog driver and use them to stop
and restart the watchdog during system suspend and resume,
respectively, if the system is not going to enter an ACPI
sleep state (in which case the watchdog will be stopped
by the platform firmware before the state is entered).
Reported-and-tested-by: Borun Fu <borun.fu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
The watchdog's parent is iTCO_wdt (the platform device) not lpc_ich
(the PCI device.) Setting the parent right makes it much easier for
the user to figure out which driver/module is handling the watchdog
device node.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
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>
Some new Atom's, eg Avoton and Bay Trail, have slightly different iTCO
functionality:
- The watchdog timer ticks at 1 second instead of .6 seconds
- Some 8 and 16-bit registers were combined into 32-bit registers
- Some registers were removed (DAT_IN, DAT_OUT, MESSAGE)
- The BOOT_STS field in TCO_STS was removed
- The NO_REBOOT bit is in the PMC area instead of GCS
Update the driver to support the above changes and bump the version to
1.11.
Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Tested-by: Rajat Jain <rajatjain@juniper.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
I just can't find any value in MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR)
and MODULE_ALIAS_MISCDEV(TEMP_MINOR) statements.
Either the device is enumerated and the driver already has a module
alias (e.g. PCI, USB etc.) that will get the right driver loaded
automatically.
Or the device is not enumerated and loading its driver will lead to
more or less intrusive hardware poking. Such hardware poking should be
limited to a bare minimum, so the user should really decide which
drivers should be tried and in what order. Trying them all in
arbitrary order can't do any good.
On top of that, loading that many drivers at once bloats the kernel
log. Also many drivers will stay loaded afterward, bloating the output
of "lsmod" and wasting memory. Some modules (cs5535_mfgpt which gets
loaded as a dependency) can't even be unloaded!
If defining char-major-10-130 is needed then it should happen in
user-space.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Cc: Jim Cromie <jim.cromie@gmail.com>
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.
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>
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds the Watchdog Timer Device IDs for the Intel Lynx Point-LP PCH.
The Device IDs are defined in drivers/mfd/lpc_ich.c
Signed-off-by: James Ralston <james.d.ralston@intel.com>
Acked-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The recent conversion of iTCO_wdt resulted in the driver no longer
getting loaded automatically, since it no longer has a
MODULE_DEVICE_TABLE() included. As the lpc_ich driver now creates a
platform device, auto-loading can easily be done by having a respective
module alias in place.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Aaron Sierra <asierra@xes-inc.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Fix printk format warnings:
drivers/watchdog/iTCO_wdt.c:577:3: warning: format '%04llx' expects type 'long long unsigned int', but argument 2 has type 'resource_size_t'
drivers/watchdog/iTCO_wdt.c:594:3: warning: format '%04llx' expects type 'long long unsigned int', but argument 2 has type 'resource_size_t'
drivers/watchdog/iTCO_wdt.c:600:2: warning: format '%04llx' expects type 'long long unsigned int', but argument 4 has type 'resource_size_t'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This patch converts the iTCO_wdt driver to use the multi-function device
driver model. It uses resources discovered by the lpc_ich driver, so that
it no longer does its own PCI scanning.
Signed-off-by: Aaron Sierra <asierra@xes-inc.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Use the current logging styles.
Make sure all output has a prefix.
Add missing newlines.
Remove now unnecessary PFX, NAME, and miscellaneous other #defines.
Coalesce formats.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This patch adds the TCO Watchdog DeviceIDs for the Intel Lynx Point PCH.
Signed-off-by: Seth Heasley <seth.heasley@intel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Redhat Bugzilla: Bug 727875 - TCO_EN bit is disabled by TCO driver
The previous patch breaks reset watchdog behaviour on the older hardware.
It is therefor better to make sure that the behaviour for older hardware (<=ICH5 or
6300ESB) is preserved and that the behaviour for newer hardware is changed.
We therefor use the iTCO_version to see if we need the clearing of the SMI_TCO_EN
bit in the SMI_EN register.
So the new behaviour becomes:
turn_SMI_watchdog_clear_off=0 -> Do not turn off SMI clearing watchdog.
turn_SMI_watchdog_clear_off=1 -> Turn off SMI clearing watchdog when iTCO_version=1
(ICHO till ICH5 + 6300ESB only)
turn_SMI_watchdog_clear_off=2 -> Turn off SMI clearing watchdog.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Redhat Bugzilla: Bug 727875 - TCO_EN bit is disabled by TCO driver
Jiri Slaby: 28d41f53f broke temperature sensors on a ICH10 chipset
The iTCO_wdt driver disables the SMI. This breaks good working of newer hardware.
The disabling of the SMI by the TCO logic dates back from the i810-tco driver
from Nils Faerber (around 28 July 2000). The reason for this was that some BIOSes
install handlers reset or disable the watchdog timer instead of resetting the system.
The trick to fix this was to disable the SMI (by clearing the SMI_TCO_EN bit of the
SMI_EN register) to prevent this from happening.
This however has strange effects on newer hardware. So we are in a situation that
a fix for broken old hardware affects newer hardware.
The correct solution is to make this fix an option (with the new module parameter:
turn_SMI_watchdog_clear_off) so that the default behaviour is the unfixed version.
the next patch will be to move this in the start and stop functions of the driver
and to add a new module parameter for the global_smi_en bit and to get rid of the
vendor_support code.
This fix can have an effect on old (typical ICH & ICH2 chipsets) motherboards that
have a broken BIOS implementation concerning TCO logic. In these case the module
parameter turn_SMI_watchdog_clear_off=1 will need to be added.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
While checking what watchdog drivers usually do in suspend/resume to
spot common behaviour for the watchdog framework, I found these drivers
which do nothing but add some cruft. Remove it, it is superfluous. New
approaches should probably be done with pm_ops anyway.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
