Address the need for a recovery method (firmware flash on Firmware errors)
introduced in the later patches of Xe KMD.
Whenever XE KMD detects a firmware error, a firmware flash is required to
recover the device to normal operation.
The initial proposal to use 'firmware-flash' as a recovery method was
not applicable to other drivers and could cause multiple recovery
methods specific to vendors to be added.
To address this a more generic 'vendor-specific' method is introduced,
guiding users to refer to vendor specific documentation and system logs
for detailed vendor specific recovery procedure.
Add a recovery method 'WEDGED=vendor-specific' for such errors.
Vendors must provide additional recovery documentation if this method
is used.
It is the responsibility of the consumer to refer to the correct vendor
specific documentation and usecase before attempting a recovery.
For example: If driver is XE KMD, the consumer must refer
to the documentation of 'Device Wedging' under 'Documentation/gpu/xe/'.
Recovery script contributed by Raag.
v2: fix documentation (Raag)
v3: add more details to commit message (Sima, Rodrigo, Raag)
add an example script to the documentation (Raag)
v4: use consistent naming (Raag)
v5: fix commit message
Cc: André Almeida <andrealm...@igalia.com>
Cc: Christian König <christian.koe...@amd.com>
Cc: David Airlie <airl...@gmail.com>
Cc: Simona Vetter <simona.vet...@ffwll.ch>
Co-developed-by: Raag Jadav <raag.ja...@intel.com>
Signed-off-by: Raag Jadav <raag.ja...@intel.com>
Signed-off-by: Riana Tauro <riana.ta...@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.v...@intel.com>
---
Documentation/gpu/drm-uapi.rst | 42 ++++++++++++++++++++++++++++------
drivers/gpu/drm/drm_drv.c | 2 ++
include/drm/drm_device.h | 4 ++++
3 files changed, 41 insertions(+), 7 deletions(-)
diff --git a/Documentation/gpu/drm-uapi.rst b/Documentation/gpu/drm-uapi.rst
index 843facf01b2d..5691b29acde3 100644
--- a/Documentation/gpu/drm-uapi.rst
+++ b/Documentation/gpu/drm-uapi.rst
@@ -418,13 +418,15 @@ needed.
Recovery
--------
-Current implementation defines three recovery methods, out of which, drivers
+Current implementation defines four recovery methods, out of which, drivers
can use any one, multiple or none. Method(s) of choice will be sent in the
uevent environment as ``WEDGED=<method1>[,..,<methodN>]`` in order of less to
-more side-effects. If driver is unsure about recovery or method is unknown
-(like soft/hard system reboot, firmware flashing, physical device replacement
-or any other procedure which can't be attempted on the fly), ``WEDGED=unknown``
-will be sent instead.
+more side-effects. If recovery method is specific to vendor
+``WEDGED=vendor-specific`` will be sent and userspace should refer to vendor
+specific documentation for the recovery procedure. As an example if the driver
+is 'Xe' then the documentation for 'Device Wedging' of Xe driver needs to be
+referred for the recovery procedure. If driver is unsure about recovery or
+method is unknown, ``WEDGED=unknown`` will be sent instead.
Userspace consumers can parse this event and attempt recovery as per the
following expectations.
@@ -435,6 +437,7 @@ following expectations.
none optional telemetry collection
rebind unbind + bind driver
bus-reset unbind + bus reset/re-enumeration + bind
+ vendor-specific vendor specific recovery method
unknown consumer policy
=============== ========================================
@@ -472,8 +475,12 @@ erroring out, all device memory should be unmapped and
file descriptors should
be closed to prevent leaks or undefined behaviour. The idea here is to clear
the
device of all user context beforehand and set the stage for a clean recovery.
-Example
--------
+For ``WEDGED=vendor-specific`` recovery method, it is the responsibility of the
+consumer to check the driver documentation and the usecase before attempting
+a recovery.
+
+Example - rebind
+----------------
Udev rule::
@@ -491,6 +498,27 @@ Recovery script::
echo -n $DEVICE > $DRIVER/unbind
echo -n $DEVICE > $DRIVER/bind
+Example - vendor-specific
+-------------------------
+
+Udev rule::
+
+ SUBSYSTEM=="drm", ENV{WEDGED}=="vendor-specific",
DEVPATH=="*/drm/card[0-9]",
+ RUN+="/path/to/vendor_specific_recovery.sh $env{DEVPATH}"
+
+Recovery script::
+
+ #!/bin/sh
+
+ DEVPATH=$(readlink -f /sys/$1/device)
+ DRIVERPATH=$(readlink -f $DEVPATH/driver)
+ DRIVER=$(basename $DRIVERPATH)
+
+ if [ "$DRIVER" = "xe" ]; then
+ # Refer XE documentation and check usecase and recovery procedure
+ fi
+
+
Customization
-------------
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index cdd591b11488..0ac723a46a91 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -532,6 +532,8 @@ static const char *drm_get_wedge_recovery(unsigned int opt)
return "rebind";
case DRM_WEDGE_RECOVERY_BUS_RESET:
return "bus-reset";
+ case DRM_WEDGE_RECOVERY_VENDOR:
+ return "vendor-specific";
default:
return NULL;
}
diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h
index a33aedd5e9ec..59fd3f4d5995 100644
--- a/include/drm/drm_device.h
+++ b/include/drm/drm_device.h
@@ -26,10 +26,14 @@ struct pci_controller;
* Recovery methods for wedged device in order of less to more side-effects.
* To be used with drm_dev_wedged_event() as recovery @method. Callers can
* use any one, multiple (or'd) or none depending on their needs.
+ *
+ * Refer to "Device Wedging" chapter in Documentation/gpu/drm-uapi.rst for more
+ * details.
*/
#define DRM_WEDGE_RECOVERY_NONE BIT(0) /* optional telemetry
collection */
#define DRM_WEDGE_RECOVERY_REBIND BIT(1) /* unbind + bind driver */
#define DRM_WEDGE_RECOVERY_BUS_RESET BIT(2) /* unbind + reset bus device +
bind */
+#define DRM_WEDGE_RECOVERY_VENDOR BIT(3) /* vendor specific recovery
method */
/**
* struct drm_wedge_task_info - information about the guilty task of a wedge
dev
--
2.47.1
