| Message ID | 1590655103-21568-1-git-send-email-mkrishn@codeaurora.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v1] drm/msm: add shutdown support for display platform_driver | expand |
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
Quoting Krishna Manikandan (2020-05-28 01:38:23) > 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; > + } When would this ever happen? Please drop this useless check. > + > + 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 },
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,
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(+)