WDAT table on Lenovo Z50-70 is using RTC SRAM (ports 0x70 and 0x71) to
store state of the timer. This conflicts with Linux RTC driver
(rtc-cmos.c) who fails to reserve those ports for itself preventing RTC
from functioning. In addition the WDAT table seems not to be fully
functional because it does not reset the system when the watchdog times
out.
On this system iTCO_wdt works just fine so we simply prefer to use it
instead of WDAT. This makes RTC working again and also results working
watchdog via iTCO_wdt.
Reported-by: Peter Milley <pbmilley@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=199033
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The resource allocation in WDAT watchdog has off-one-by error, it sets
one byte more than the actual end address. This may eventually lead
to unexpected resource conflicts.
Fixes: 058dfc7670 (ACPI / watchdog: Add support for WDAT hardware watchdog)
Cc: 4.9+ <stable@vger.kernel.org> # 4.9+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We copy a local resource structure into a list, but only
initialize some of its members, as pointed out by gcc-4.4:
drivers/acpi/acpi_watchdog.c: In function 'acpi_watchdog_init':
drivers/acpi/acpi_watchdog.c:105: error: 'res.child' may be used uninitialized in this function
drivers/acpi/acpi_watchdog.c:105: error: 'res.sibling' may be used uninitialized in this function
drivers/acpi/acpi_watchdog.c:105: error: 'res.parent' may be used uninitialized in this function
drivers/acpi/acpi_watchdog.c:105: error: 'res.desc' may be used uninitialized in this function
drivers/acpi/acpi_watchdog.c:105: error: 'res.name' may be used uninitialized in this function
Newer compilers can presumably optimize the uninitialized access
away entirely and don't warn at all, but rely on the kzalloc()
to zero the structure first. This adds an explicit initialization
to force consistent behavior.
Fixes: 058dfc7670 (ACPI / watchdog: Add support for WDAT hardware watchdog)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Partially overlapping regions cause platform device creation
to fail. The latter of two overlapping resources will fail to be
reserved. Fix this by merging overlapping resource ranges while
enumerating WDAT table entries.
Signed-off-by: Ryan Kennedy <ryan5544@gmail.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If the platform device creation fails for whichever reason the driver
prints out something like:
[ 0.978837] ACPI: watchdog: Failed to create platform device
However, that is quite confusing and does not include any information
why it failed. To make it more understandable, reword it like:
[ 0.978837] ACPI: watchdog: Device creation failed: -16
Which tells that we failed to create the watchdog device because some of
the resources were already reserved (-EBUSY).
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Starting from Intel Skylake the iTCO watchdog timer registers were moved to
reside in the same register space with SMBus host controller. Not all
needed registers are available though and we need to unhide P2SB (Primary
to Sideband) device briefly to be able to read status of required NO_REBOOT
bit. The i2c-i801.c SMBus driver used to handle this and creation of the
iTCO watchdog platform device.
Windows, on the other hand, does not use the iTCO watchdog hardware
directly even if it is available. Instead it relies on ACPI Watchdog Action
Table (WDAT) table to describe the watchdog hardware to the OS. This table
contains necessary information about the the hardware and also set of
actions which are executed by a driver as needed.
This patch implements a new watchdog driver that takes advantage of the
ACPI WDAT table. We split the functionality into two parts: first part
enumerates the WDAT table and if found, populates resources and creates
platform device for the actual driver. The second part is the driver
itself.
The reason for the split is that this way we can make the driver itself to
be a module and loaded automatically if the WDAT table is found. Otherwise
the module is not loaded.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
