[PATCH v2 1/4] drm/msm/adreno: fix runtime PM imbalance at unbind

[PATCH v2 1/4] drm/msm/adreno: fix runtime PM imbalance at unbind

[Johan Hovold]

A recent commit moved enabling of runtime PM from adreno_gpu_init() to
adreno_load_gpu() (called on first open()), which means that unbind()
may now be called with runtime PM disabled in case the device was never
opened in between.

Make sure to only forcibly suspend and disable runtime PM at unbind() in
case runtime PM has been enabled to prevent a disable count imbalance.

This specifically avoids leaving runtime PM disabled when the device
is later opened after a successful bind:

	msm_dpu ae01000.display-controller: [drm:adreno_load_gpu [msm]] *ERROR* Couldn't power up the GPU: -13

Fixes: 4b18299b3365 ("drm/msm/adreno: Defer enabling runpm until hw_init()")
Reported-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Link: https://lore.kernel.org/lkml/20230203181245.3523937-1-quic_bjorande@quicinc.com
Cc: stable@vger.kernel.org	# 6.0
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
 drivers/gpu/drm/msm/adreno/adreno_device.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/adreno/adreno_device.c b/drivers/gpu/drm/msm/adreno/adreno_device.c
index 36f062c7582f..c5c4c93b3689 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_device.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_device.c
@@ -558,7 +558,8 @@ static void adreno_unbind(struct device *dev, struct device *master,
 	struct msm_drm_private *priv = dev_get_drvdata(master);
 	struct msm_gpu *gpu = dev_to_gpu(dev);
 
-	WARN_ON_ONCE(adreno_system_suspend(dev));
+	if (pm_runtime_enabled(dev))
+		WARN_ON_ONCE(adreno_system_suspend(dev));
 	gpu->funcs->destroy(gpu);
 
 	priv->gpu_pdev = NULL;
-- 
2.39.2

[PATCH v2 2/4] drm/msm/adreno: fix runtime PM imbalance at gpu load

[Johan Hovold]

A recent commit moved enabling of runtime PM to GPU load time (first
open()) but failed to update the error paths so that runtime PM is
disabled if initialisation of the GPU fails. This would trigger a
warning about the unbalanced disable count on the next open() attempt.

Note that pm_runtime_put_noidle() is sufficient to balance the usage
count when pm_runtime_put_sync() fails (and is chosen over
pm_runtime_resume_and_get() for consistency reasons).

Fixes: 4b18299b3365 ("drm/msm/adreno: Defer enabling runpm until hw_init()")
Cc: stable@vger.kernel.org      # 6.0
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
 drivers/gpu/drm/msm/adreno/adreno_device.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/adreno_device.c b/drivers/gpu/drm/msm/adreno/adreno_device.c
index c5c4c93b3689..f9a0b11c2e43 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_device.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_device.c
@@ -443,20 +443,21 @@ struct msm_gpu *adreno_load_gpu(struct drm_device *dev)
 
 	ret = pm_runtime_get_sync(&pdev->dev);
 	if (ret < 0) {
-		pm_runtime_put_sync(&pdev->dev);
+		pm_runtime_put_noidle(&pdev->dev);
 		DRM_DEV_ERROR(dev->dev, "Couldn't power up the GPU: %d\n", ret);
-		return NULL;
+		goto err_disable_rpm;
 	}
 
 	mutex_lock(&gpu->lock);
 	ret = msm_gpu_hw_init(gpu);
 	mutex_unlock(&gpu->lock);
-	pm_runtime_put_autosuspend(&pdev->dev);
 	if (ret) {
 		DRM_DEV_ERROR(dev->dev, "gpu hw init failed: %d\n", ret);
-		return NULL;
+		goto err_put_rpm;
 	}
 
+	pm_runtime_put_autosuspend(&pdev->dev);
+
 #ifdef CONFIG_DEBUG_FS
 	if (gpu->funcs->debugfs_init) {
 		gpu->funcs->debugfs_init(gpu, dev->primary);
@@ -465,6 +466,13 @@ struct msm_gpu *adreno_load_gpu(struct drm_device *dev)
 #endif
 
 	return gpu;
+
+err_put_rpm:
+	pm_runtime_put_sync(&pdev->dev);
+err_disable_rpm:
+	pm_runtime_disable(&pdev->dev);
+
+	return NULL;
 }
 
 static int find_chipid(struct device *dev, struct adreno_rev *rev)
-- 
2.39.2