Re: [REPOST PATCH v4 06/13] drm/msm/disp/dpu1: Add DSC support in hw_ctl

From: Marijn Suijten
Date: Thu Feb 17 2022 - 17:20:38 EST


On 2022-02-10 16:04:16, Vinod Koul wrote:
> Later gens of hardware have DSC bits moved to hw_ctl, so configure these
> bits so that DSC would work there as well
>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c | 11 ++++++++++-
> drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h | 2 ++
> 2 files changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c
> index 02da9ecf71f1..49659165cea8 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c
> @@ -25,6 +25,8 @@
> #define CTL_MERGE_3D_ACTIVE 0x0E4
> #define CTL_INTF_ACTIVE 0x0F4
> #define CTL_MERGE_3D_FLUSH 0x100
> +#define CTL_DSC_ACTIVE 0x0E8
> +#define CTL_DSC_FLUSH 0x104
> #define CTL_INTF_FLUSH 0x110
> #define CTL_INTF_MASTER 0x134
> #define CTL_FETCH_PIPE_ACTIVE 0x0FC
> @@ -34,6 +36,7 @@
>
> #define DPU_REG_RESET_TIMEOUT_US 2000
> #define MERGE_3D_IDX 23
> +#define DSC_IDX 22

This define does not seem used in any of these patches. Is that
intended?

> #define INTF_IDX 31
> #define CTL_INVALID_BIT 0xffff
> #define CTL_DEFAULT_GROUP_ID 0xf
> @@ -121,7 +124,6 @@ static u32 dpu_hw_ctl_get_pending_flush(struct dpu_hw_ctl *ctx)
>
> static inline void dpu_hw_ctl_trigger_flush_v1(struct dpu_hw_ctl *ctx)
> {
> -
> if (ctx->pending_flush_mask & BIT(MERGE_3D_IDX))
> DPU_REG_WRITE(&ctx->hw, CTL_MERGE_3D_FLUSH,
> ctx->pending_merge_3d_flush_mask);
> @@ -506,6 +508,9 @@ static void dpu_hw_ctl_intf_cfg_v1(struct dpu_hw_ctl *ctx,
> if ((test_bit(DPU_CTL_VM_CFG, &ctx->caps->features)))
> mode_sel = CTL_DEFAULT_GROUP_ID << 28;
>
> + if (cfg->dsc)
> + DPU_REG_WRITE(&ctx->hw, CTL_DSC_FLUSH, cfg->dsc);
> +
> if (cfg->intf_mode_sel == DPU_CTL_MODE_SEL_CMD)
> mode_sel |= BIT(17);
>
> @@ -517,6 +522,10 @@ static void dpu_hw_ctl_intf_cfg_v1(struct dpu_hw_ctl *ctx,
> if (cfg->merge_3d)
> DPU_REG_WRITE(c, CTL_MERGE_3D_ACTIVE,
> BIT(cfg->merge_3d - MERGE_3D_0));
> + if (cfg->dsc) {
> + DPU_REG_WRITE(&ctx->hw, CTL_FLUSH, cfg->dsc);

Perhaps this should have been `DSC_IDX`, as the index to flush is set in
the CTL_DSC_FLUSH register already? Should this go through
pending_flush_mask machinery?

> + DPU_REG_WRITE(c, CTL_DSC_ACTIVE, cfg->dsc);
> + }
> }
>
> static void dpu_hw_ctl_intf_cfg(struct dpu_hw_ctl *ctx,
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h
> index 806c171e5df2..9847c9c46d6f 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h
> @@ -40,6 +40,7 @@ struct dpu_hw_stage_cfg {
> * @merge_3d: 3d merge block used
> * @intf_mode_sel: Interface mode, cmd / vid
> * @stream_sel: Stream selection for multi-stream interfaces
> + * @dsc: DSC BIT masks

Bit masks of what? Enabled DSCs? A more verbose doc-comment is desired
here, matching the rest of the fields :) - something like "DSC block(s)
used" similar to merge_3d? Or copy the docs from `dsc_mask`, which is
the value that is written into this field.

- Marijn

> */
> struct dpu_hw_intf_cfg {
> enum dpu_intf intf;
> @@ -47,6 +48,7 @@ struct dpu_hw_intf_cfg {
> enum dpu_merge_3d merge_3d;
> enum dpu_ctl_mode_sel intf_mode_sel;
> int stream_sel;
> + unsigned int dsc;
> };
>
> /**
> --
> 2.31.1
>