On 2023-05-02 14:02:59, Kuogee Hsieh wrote:
> During DSC setup, the crossbar mux need to be programmed to engage
> DSC to specified PINGPONG. Hence during tear down, the crossbar mux
> need to be reset to disengage DSC from PINGPONG. This patch add
> PINGPONG_NONE to serve as disable to reset crossbar mux.
This patch doesn't *just add* PINGPONG_NONE to reset the crossbar; that
functionality was already available thanks to a `bool enable` function
parameter. Instead it should explain why you think PINGPONG_NONE is
more convenient than passing a bool that warrants this replacement.
(Hint: I think because you don't have a hw_pp->idx available in the
teardown path, and/or its value is not relevant for the disable case
anyway.)
In addition I don't see this series use PINGPONG_NONE anywhere yet: will
that be added in the DSC 1.2 series for DP (to support hotplug)?
> Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 2 +-
> drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c | 7 +++----
> drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.h | 1 -
> drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h | 3 ++-
> 4 files changed, 6 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> index 1dc5dbe..d9ad334 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> @@ -1839,7 +1839,7 @@ static void dpu_encoder_dsc_pipe_cfg(struct dpu_hw_dsc *hw_dsc,
> hw_pp->ops.setup_dsc(hw_pp);
>
> if (hw_dsc->ops.dsc_bind_pingpong_blk)
> - hw_dsc->ops.dsc_bind_pingpong_blk(hw_dsc, true, hw_pp->idx);
> + hw_dsc->ops.dsc_bind_pingpong_blk(hw_dsc, hw_pp->idx);
>
> if (hw_pp->ops.enable_dsc)
> hw_pp->ops.enable_dsc(hw_pp);
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c
> index 4a6bbcc..3e68d47 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c
> @@ -157,7 +157,6 @@ static void dpu_hw_dsc_config_thresh(struct dpu_hw_dsc *hw_dsc,
>
> static void dpu_hw_dsc_bind_pingpong_blk(
> struct dpu_hw_dsc *hw_dsc,
> - bool enable,
> const enum dpu_pingpong pp)
> {
> struct dpu_hw_blk_reg_map *c = &hw_dsc->hw;
> @@ -166,13 +165,13 @@ static void dpu_hw_dsc_bind_pingpong_blk(
>
> dsc_ctl_offset = DSC_CTL(hw_dsc->idx);
>
> - if (enable)
> + if (pp)
> mux_cfg = (pp - PINGPONG_0) & 0x7;
>
> DRM_DEBUG_KMS("%s dsc:%d %s pp:%d\n",
> - enable ? "Binding" : "Unbinding",
> + pp ? "Binding" : "Unbinding",
> hw_dsc->idx - DSC_0,
> - enable ? "to" : "from",
> + pp ? "to" : "from",
> pp - PINGPONG_0);
PINGPONG_NONE - PINGPONG_0 = -1, so this whole debug log likely needs to
be rewritten for the disable case as we don't know what PINGPONG it is
being unbound from. How about:
if (pp)
DRM_DEBUG_KMS("Binding dsc:%d to pp:%d\n",
hw_dsc->idx - DSC_0,
pp - PINGPONG_0);
else
DRM_DEBUG_KMS("Unbinding dsc:%d from any pp\n",
hw_dsc->idx - DSC_0);
- Marijn
>
> DPU_REG_WRITE(c, dsc_ctl_offset, mux_cfg);
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.h
> index 287ec5f..138080a 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.h
> @@ -44,7 +44,6 @@ struct dpu_hw_dsc_ops {
> struct drm_dsc_config *dsc);
>
> void (*dsc_bind_pingpong_blk)(struct dpu_hw_dsc *hw_dsc,
> - bool enable,
> enum dpu_pingpong pp);
> };
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
> index 2d9192a..56826a9 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h
> @@ -191,7 +191,8 @@ enum dpu_dsc {
> };
>
> enum dpu_pingpong {
> - PINGPONG_0 = 1,
> + PINGPONG_NONE,
> + PINGPONG_0,
> PINGPONG_1,
> PINGPONG_2,
> PINGPONG_3,
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>
