drm/panthor: Ignore devfreq_{suspend, resume}_device() failures

devfreq_{resume,suspend}_device() don't bother undoing the suspend_count
modifications if something fails, so either it assumes failures are
harmless, or it's super fragile/buggy. In either case it's not something
we can address at the driver level, so let's just assume failures are
harmless for now, like is done in panfrost.

v3:
- Add R-b

v2:
- Add R-b

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Adrian Larumbe <adrian.larumbe@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241211075419.2333731-4-boris.brezillon@collabora.com

diff --git a/drivers/gpu/drm/panthor/panthor_devfreq.c b/drivers/gpu/drm/panthor/panthor_devfreq.c
index ecc7a52bd688ee0cf4635af0d8a5b7631357502c..3686515d368db5bb329f4858d4a7247a4957cc24 100644 (file)
--- a/drivers/gpu/drm/panthor/panthor_devfreq.c
+++ b/drivers/gpu/drm/panthor/panthor_devfreq.c
@@ -243,26 +243,26 @@ int panthor_devfreq_init(struct panthor_device *ptdev)
        return 0;
 }
 
-int panthor_devfreq_resume(struct panthor_device *ptdev)
+void panthor_devfreq_resume(struct panthor_device *ptdev)
 {
        struct panthor_devfreq *pdevfreq = ptdev->devfreq;
 
        if (!pdevfreq->devfreq)
-               return 0;
+               return;
 
        panthor_devfreq_reset(pdevfreq);
 
-       return devfreq_resume_device(pdevfreq->devfreq);
+       drm_WARN_ON(&ptdev->base, devfreq_resume_device(pdevfreq->devfreq));
 }
 
-int panthor_devfreq_suspend(struct panthor_device *ptdev)
+void panthor_devfreq_suspend(struct panthor_device *ptdev)
 {
        struct panthor_devfreq *pdevfreq = ptdev->devfreq;
 
        if (!pdevfreq->devfreq)
-               return 0;
+               return;
 
-       return devfreq_suspend_device(pdevfreq->devfreq);
+       drm_WARN_ON(&ptdev->base, devfreq_suspend_device(pdevfreq->devfreq));
 }
 
 void panthor_devfreq_record_busy(struct panthor_device *ptdev)

diff --git a/drivers/gpu/drm/panthor/panthor_devfreq.h b/drivers/gpu/drm/panthor/panthor_devfreq.h
index 83a5c95224934760dabee257d8a9988f5672ff92..b7631de695f7d79456478c87e8af5dc47673cd1d 100644 (file)
--- a/drivers/gpu/drm/panthor/panthor_devfreq.h
+++ b/drivers/gpu/drm/panthor/panthor_devfreq.h
@@ -12,8 +12,8 @@ struct panthor_devfreq;
 
 int panthor_devfreq_init(struct panthor_device *ptdev);
 
-int panthor_devfreq_resume(struct panthor_device *ptdev);
-int panthor_devfreq_suspend(struct panthor_device *ptdev);
+void panthor_devfreq_resume(struct panthor_device *ptdev);
+void panthor_devfreq_suspend(struct panthor_device *ptdev);
 
 void panthor_devfreq_record_busy(struct panthor_device *ptdev);
 void panthor_devfreq_record_idle(struct panthor_device *ptdev);

diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c
index b3c117d55c2aee751115583dd68015a7ff57da8f..4faca2684324cbb8b9586ac87f983aac89ebd172 100644 (file)
--- a/drivers/gpu/drm/panthor/panthor_device.c
+++ b/drivers/gpu/drm/panthor/panthor_device.c
@@ -457,9 +457,7 @@ int panthor_device_resume(struct device *dev)
        if (ret)
                goto err_disable_stacks_clk;
 
-       ret = panthor_devfreq_resume(ptdev);
-       if (ret)
-               goto err_disable_coregroup_clk;
+       panthor_devfreq_resume(ptdev);
 
        if (panthor_device_is_initialized(ptdev) &&
            drm_dev_enter(&ptdev->base, &cookie)) {
@@ -496,8 +494,6 @@ int panthor_device_resume(struct device *dev)
 
 err_suspend_devfreq:
        panthor_devfreq_suspend(ptdev);
-
-err_disable_coregroup_clk:
        clk_disable_unprepare(ptdev->clks.coregroup);
 
 err_disable_stacks_clk:
@@ -514,7 +510,7 @@ err_set_suspended:
 int panthor_device_suspend(struct device *dev)
 {
        struct panthor_device *ptdev = dev_get_drvdata(dev);
-       int ret, cookie;
+       int cookie;
 
        if (atomic_read(&ptdev->pm.state) != PANTHOR_DEVICE_PM_STATE_ACTIVE)
                return -EINVAL;
@@ -546,36 +542,11 @@ int panthor_device_suspend(struct device *dev)
                drm_dev_exit(cookie);
        }
 
-       ret = panthor_devfreq_suspend(ptdev);
-       if (ret) {
-               if (panthor_device_is_initialized(ptdev) &&
-                   drm_dev_enter(&ptdev->base, &cookie)) {
-                       panthor_gpu_resume(ptdev);
-                       panthor_mmu_resume(ptdev);
-                       drm_WARN_ON(&ptdev->base, panthor_fw_resume(ptdev));
-                       panthor_sched_resume(ptdev);
-                       drm_dev_exit(cookie);
-               }
-
-               goto err_set_active;
-       }
+       panthor_devfreq_suspend(ptdev);
 
        clk_disable_unprepare(ptdev->clks.coregroup);
        clk_disable_unprepare(ptdev->clks.stacks);
        clk_disable_unprepare(ptdev->clks.core);
        atomic_set(&ptdev->pm.state, PANTHOR_DEVICE_PM_STATE_SUSPENDED);
        return 0;
-
-err_set_active:
-       /* If something failed and we have to revert back to an
-        * active state, we also need to clear the MMIO userspace
-        * mappings, so any dumb pages that were mapped while we
-        * were trying to suspend gets invalidated.
-        */
-       mutex_lock(&ptdev->pm.mmio_lock);
-       atomic_set(&ptdev->pm.state, PANTHOR_DEVICE_PM_STATE_ACTIVE);
-       unmap_mapping_range(ptdev->base.anon_inode->i_mapping,
-                           DRM_PANTHOR_USER_MMIO_OFFSET, 0, 1);
-       mutex_unlock(&ptdev->pm.mmio_lock);
-       return ret;
 }