[v1] drm/msm: add shutdown support for display platform_driver
diff mbox series

Message ID 1590655103-21568-1-git-send-email-mkrishn@codeaurora.org
State New
Headers show
Series
  • [v1] drm/msm: add shutdown support for display platform_driver
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Commit Message

Krishna Manikandan May 28, 2020, 8:38 a.m. UTC
Define shutdown callback for display drm driver,
so as to disable all the CRTCS when shutdown
notification is received by the driver.

Signed-off-by: Krishna Manikandan <mkrishn@codeaurora.org>
---
 drivers/gpu/drm/msm/msm_drv.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

Comments

Sai Prakash Ranjan May 28, 2020, 8:58 a.m. UTC | #1
Hi Krishna,

On 2020-05-28 14:08, Krishna Manikandan wrote:
> Define shutdown callback for display drm driver,
> so as to disable all the CRTCS when shutdown
> notification is received by the driver.
> 

Would be nice to add some more context for adding this shutdown callback
something like below:

If the hardware is still accessing memory after SMMU translation is 
disabled
as part of smmu shutdown callback,  then the IOVAs(I/O virtual address) 
which
it was using will go on the bus as the physical addresses which will 
result
in unknown crashes (NoC/interconnect errors on QCOM SoCs).

PS: Credits for description: Robin Murphy

Thanks,
Sai

Patch
diff mbox series

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index e4b750b..7a8953f 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -1322,6 +1322,18 @@  static int msm_pdev_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static void msm_pdev_shutdown(struct platform_device *pdev)
+{
+	struct drm_device *drm = platform_get_drvdata(pdev);
+
+	if (!drm) {
+		DRM_ERROR("Invalid drm device node\n");
+		return;
+	}
+
+	drm_atomic_helper_shutdown(drm);
+}
+
 static const struct of_device_id dt_match[] = {
 	{ .compatible = "qcom,mdp4", .data = (void *)KMS_MDP4 },
 	{ .compatible = "qcom,mdss", .data = (void *)KMS_MDP5 },
@@ -1334,6 +1346,7 @@  static int msm_pdev_remove(struct platform_device *pdev)
 static struct platform_driver msm_platform_driver = {
 	.probe      = msm_pdev_probe,
 	.remove     = msm_pdev_remove,
+	.shutdown   = msm_pdev_shutdown,
 	.driver     = {
 		.name   = "msm",
 		.of_match_table = dt_match,