Hi,
On Mon, Mar 30, 2020 at 2:04 AM Kalyan Thota <kalyan_t@xxxxxxxxxxxxxx> wrote:
>
> "The PM core always increments the runtime usage counter
> before calling the ->suspend() callback and decrements it
> after calling the ->resume() callback"
>
> DPU and DSI are managed as runtime devices. When
> suspend is triggered, PM core adds a refcount on all the
> devices and calls device suspend, since usage count is
> already incremented, runtime suspend was not getting called
> and it kept the clocks on which resulted in target not
> entering into XO shutdown.
>
> Add changes to manage runtime devices during pm sleep.
>
> Changes in v1:
> - Remove unnecessary checks in the function
> _dpu_kms_disable_dpu (Rob Clark).
>
> Changes in v2:
> - Avoid using suspend_late to reset the usagecount
> as suspend_late might not be called during suspend
> call failures (Doug).
>
> Signed-off-by: Kalyan Thota <kalyan_t@xxxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 33 +++++++++++++++++++++++++++++++++
> drivers/gpu/drm/msm/msm_drv.c | 4 ++++
> drivers/gpu/drm/msm/msm_kms.h | 2 ++
> 3 files changed, 39 insertions(+)
I am still 100% baffled by your patch and I never did quite understand
your response to my previous comments [1]. I think you're saying that
the problem you were facing is that if you call "suspend" but never
called "runtime_suspend" that the device stays active. Is that right?
If that's true, did you try something like this suggestion I made?
SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> index ce19f1d..2343cbd 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> @@ -26,6 +26,7 @@
> #include "dpu_encoder.h"
> #include "dpu_plane.h"
> #include "dpu_crtc.h"
> +#include "dsi.h"
>
> #define CREATE_TRACE_POINTS
> #include "dpu_trace.h"
> @@ -325,6 +326,37 @@ static void dpu_kms_disable_commit(struct msm_kms *kms)
> pm_runtime_put_sync(&dpu_kms->pdev->dev);
> }
>
> +static void _dpu_kms_disable_dpu(struct msm_kms *kms)
> +{
> + struct dpu_kms *dpu_kms = to_dpu_kms(kms);
> + struct drm_device *dev = dpu_kms->dev;
> + struct msm_drm_private *priv = dev->dev_private;
> + struct msm_dsi *dsi;
> + int i;
> +
> + dpu_kms_disable_commit(kms);
> +
> + for (i = 0; i < ARRAY_SIZE(priv->dsi); i++) {
> + if (!priv->dsi[i])
> + continue;
> + dsi = priv->dsi[i];
> + pm_runtime_put_sync(&dsi->pdev->dev);
> + }
> + pm_runtime_put_sync(dev->dev);
> +
> + /* Increment the usagecount without triggering a resume */
> + pm_runtime_get_noresume(dev->dev);
> +
> + pm_runtime_get_noresume(&dpu_kms->pdev->dev);
> +
> + for (i = 0; i < ARRAY_SIZE(priv->dsi); i++) {
> + if (!priv->dsi[i])
> + continue;
> + dsi = priv->dsi[i];
> + pm_runtime_get_noresume(&dsi->pdev->dev);
> + }
> +}
My pm_runtime knowledge is pretty weak sometimes, but the above
function looks crazy. Maybe it's just me not understanding, but can
you please summarize what you're trying to accomplish?
-Doug
[1] https://lore.kernel.org/r/114130f68c494f83303c51157e2c5bfa@xxxxxxxxxxxxxx
