Re: [v1] drm/msm: Remove clock and bandwidth votes in mdss pm suspend

On Wed, Jan 23, 2019 at 6:12 AM Jayant Shekhar jshekhar@codeaurora.org wrote:

MDSS PM suspend is dependent on runtime suspend for disabling clocks and removing bandwidth votes. In case of pm_suspend triggered, dpm_prepare hold a refcount on power usage of device and hence runtime suspend is never triggered during pm_suspend. As runtime suspend is not triggered, clocks and bandwidth votes remain. Hence explicitly trigger mdss disable in msm_pm_suspend to disable clocks and remove the votes.

Signed-off-by: Jayant Shekhar jshekhar@codeaurora.org

drivers/gpu/drm/msm/msm_drv.c | 8 ++++++++ 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c index 5c60bb3..ffe3a25 100644 --- a/drivers/gpu/drm/msm/msm_drv.c +++ b/drivers/gpu/drm/msm/msm_drv.c @@ -1068,12 +1068,16 @@ static int msm_pm_suspend(struct device *dev) { struct drm_device *ddev = dev_get_drvdata(dev); struct msm_drm_private *priv = ddev->dev_private;

•   struct msm_mdss *mdss = priv->mdss;
  
    if (!IS_ERR_OR_NULL(priv->pm_state))
            return 0;
  
    priv->pm_state = drm_atomic_helper_suspend(ddev);
  
  

•   if (mdss && mdss->funcs)
  

•           mdss->funcs->disable(mdss);
  

This patch doesn't actually seem to apply, I guess it has a dependency on some other missing patch?

That said, shouldn't the refcount aquired in _prepare() be dropped somewhere? It seems like if all planes/crtcs/etc are disabled, we should also disable power (or at least as much as we can while still having hotplug work), so ideally drm_atomic_helper_suspend() should be enough.

BR. -R

    return IS_ERR(priv->pm_state) ? PTR_ERR(priv->pm_state) : 0;

}

@@ -1081,11 +1085,15 @@ static int msm_pm_resume(struct device *dev) { struct drm_device *ddev = dev_get_drvdata(dev); struct msm_drm_private *priv = ddev->dev_private;

•   struct msm_mdss *mdss = priv->mdss;
    int ret;
  
    if (IS_ERR_OR_NULL(priv->pm_state))
            return 0;
  
  

•   if (mdss && mdss->funcs)
  

•           mdss->funcs->enable(mdss);
  

•   ret = drm_atomic_helper_resume(ddev, priv->pm_state);
    if (ret == 0)
            priv->pm_state = NULL;
  

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