On 11/24/2022 4:02 PM, Dmitry Baryshkov wrote:
Since the commit commit c6122688f265 ("drm/msm/mdp5: stop overriding
drvdata") reading the MDP5 hw revision on db410c will crash the board
as the MDSS_GDSC is not enabled. Revert a part of the offending commit
(moving rpm enablement) and set priv->kms earlier. This make it possible
to use pm_runtime_get_sync() during read_mdp_hw_revision(), which will
power up both the MDP5 and MDSS devices.
This is the exact concern I had even when c6122688f265 was pushed.
https://patchwork.freedesktop.org/patch/508334/#comment_917689
Was the response given that time not correct then?
https://patchwork.freedesktop.org/patch/508334/#comment_917713
Fixes: c6122688f265 ("drm/msm/mdp5: stop overriding drvdata")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
index b46f983f2b46..29ae5c9613f3 100644
--- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
+++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
@@ -519,10 +519,9 @@ static void read_mdp_hw_revision(struct mdp5_kms *mdp5_kms,
struct device *dev = &mdp5_kms->pdev->dev;
u32 version;
- /* Manually enable the MDP5, as pm runtime isn't usable yet. */
- mdp5_enable(mdp5_kms);
+ pm_runtime_get_sync(dev);
version = mdp5_read(mdp5_kms, REG_MDP5_HW_VERSION);
- mdp5_disable(mdp5_kms);
+ pm_runtime_put_sync(dev);
*major = FIELD(version, MDP5_HW_VERSION_MAJOR);
*minor = FIELD(version, MDP5_HW_VERSION_MINOR);
@@ -839,6 +838,12 @@ static int mdp5_init(struct platform_device *pdev, struct drm_device *dev)
*/
clk_set_rate(mdp5_kms->core_clk, 200000000);
+ /* set uninit-ed kms */
+ priv->kms = &mdp5_kms->base.base;
+
+ pm_runtime_enable(&pdev->dev);
+ mdp5_kms->rpm_enabled = true;
+
read_mdp_hw_revision(mdp5_kms, &major, &minor);
mdp5_kms->cfg = mdp5_cfg_init(mdp5_kms, major, minor);
@@ -887,12 +892,6 @@ static int mdp5_init(struct platform_device *pdev, struct drm_device *dev)
if (ret)
goto fail;
- /* set uninit-ed kms */
- priv->kms = &mdp5_kms->base.base;
-
- pm_runtime_enable(&pdev->dev);
- mdp5_kms->rpm_enabled = true;
-
return 0;
fail:
if (mdp5_kms)
