6.16-stable review patch. If anyone has any objections, please let me know.
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From: Alessio Belle alessio.belle@imgtec.com
[ Upstream commit 551507e0d0bf32ce1d7d27533c4b98307380804c ]
The runtime PM might be left in error state if one of the callbacks returned an error, e.g. if the (auto)suspend callback failed following a firmware crash.
When that happens, any further attempt to acquire or release a power reference will then also fail, making it impossible to do anything else with the GPU. The driver logic will eventually reach the reset code.
In pvr_power_reset(), replace pvr_power_get() with a new API pvr_power_get_clear() which also attempts to clear any runtime PM error state if acquiring a power reference is not possible.
Signed-off-by: Alessio Belle alessio.belle@imgtec.com Reviewed-by: Matt Coster matt.coster@imgtec.com Link: https://lore.kernel.org/r/20250624-clear-rpm-errors-gpu-reset-v1-1-b8ff2ae55... Signed-off-by: Matt Coster matt.coster@imgtec.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/imagination/pvr_power.c | 59 ++++++++++++++++++++++++- 1 file changed, 58 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/imagination/pvr_power.c b/drivers/gpu/drm/imagination/pvr_power.c index 3e349d039fc0..187a07e0bd9a 100644 --- a/drivers/gpu/drm/imagination/pvr_power.c +++ b/drivers/gpu/drm/imagination/pvr_power.c @@ -340,6 +340,63 @@ pvr_power_device_idle(struct device *dev) return pvr_power_is_idle(pvr_dev) ? 0 : -EBUSY; }
+static int +pvr_power_clear_error(struct pvr_device *pvr_dev) +{ + struct device *dev = from_pvr_device(pvr_dev)->dev; + int err; + + /* Ensure the device state is known and nothing is happening past this point */ + pm_runtime_disable(dev); + + /* Attempt to clear the runtime PM error by setting the current state again */ + if (pm_runtime_status_suspended(dev)) + err = pm_runtime_set_suspended(dev); + else + err = pm_runtime_set_active(dev); + + if (err) { + drm_err(from_pvr_device(pvr_dev), + "%s: Failed to clear runtime PM error (new error %d)\n", + __func__, err); + } + + pm_runtime_enable(dev); + + return err; +} + +/** + * pvr_power_get_clear() - Acquire a power reference, correcting any errors + * @pvr_dev: Device pointer + * + * Attempt to acquire a power reference on the device. If the runtime PM + * is in error state, attempt to clear the error and retry. + * + * Returns: + * * 0 on success, or + * * Any error code returned by pvr_power_get() or the runtime PM API. + */ +static int +pvr_power_get_clear(struct pvr_device *pvr_dev) +{ + int err; + + err = pvr_power_get(pvr_dev); + if (err == 0) + return err; + + drm_warn(from_pvr_device(pvr_dev), + "%s: pvr_power_get returned error %d, attempting recovery\n", + __func__, err); + + err = pvr_power_clear_error(pvr_dev); + if (err) + return err; + + return pvr_power_get(pvr_dev); +} + /** * pvr_power_reset() - Reset the GPU * @pvr_dev: Device pointer @@ -364,7 +421,7 @@ pvr_power_reset(struct pvr_device *pvr_dev, bool hard_reset) * Take a power reference during the reset. This should prevent any interference with the * power state during reset. */ - WARN_ON(pvr_power_get(pvr_dev)); + WARN_ON(pvr_power_get_clear(pvr_dev));
down_write(&pvr_dev->reset_sem);