[Freedreno] [PATCH v8 3/4] drm/msm/dpu: revise timing engine programming to support widebus feature

Dmitry Baryshkov dmitry.baryshkov at linaro.org
Thu Feb 17 21:45:18 UTC 2022


On Fri, 18 Feb 2022 at 00:36, Kuogee Hsieh <quic_khsieh at quicinc.com> wrote:
>
> Widebus feature will transmit two pixel data per pixel clock to interface.
> Timing engine provides driving force for this purpose. This patch base
> on HPG (Hardware Programming Guide) to revise timing engine register
> setting to accommodate both widebus and non widebus application. Also
> horizontal width parameters need to be reduced by half since two pixel
> data are clocked out per pixel clock when widebus feature enabled.
>
> Widebus can be enabled individually at DP. However at DSI, widebus have
> to be enabled along with DSC to achieve pixel clock rate be scaled down
> with same ratio as compression ratio when 10 bits per source component.
> Therefore this patch add no supports of DSI related widebus and compression.
>
> Changes in v2:
> -- remove compression related code from timing
> -- remove op_info from  struct msm_drm_private
> -- remove unnecessary wide_bus_en variables
> -- pass wide_bus_en into timing configuration by struct msm_dp
>
> Changes in v3:
> -- split patch into 3 patches
>
> Changes in v4:
> -- rework timing engine to not interfere with dsi/hdmi
> -- cover both widebus and compression
>
> Changes in v5:
> -- remove supports of DSI widebus and compression
>
> Changes in v7:
> -- split this patch into 3 patches
> -- add Tested-by
>
> Changes in v8:
> -- move new registers writes under DATA_HCTL_EN features check.
>
> Signed-off-by: Kuogee Hsieh <quic_khsieh at quicinc.com>
> Tested-by: Bjorn Andersson <bjorn.andersson at linaro.org>

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>

> ---
>  drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c        | 10 ++++
>  drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h        |  2 +
>  .../gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c   | 14 ++++++
>  drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c        | 54 ++++++++++++++++------
>  drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.h        |  2 +
>  5 files changed, 68 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> index 0d315b4..0c22839 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> @@ -208,6 +208,8 @@ struct dpu_encoder_virt {
>
>         u32 idle_timeout;
>
> +       bool wide_bus_en;
> +
>         struct msm_dp *dp;
>  };
>
> @@ -217,6 +219,14 @@ static u32 dither_matrix[DITHER_MATRIX_SZ] = {
>         15, 7, 13, 5, 3, 11, 1, 9, 12, 4, 14, 6, 0, 8, 2, 10
>  };
>
> +
> +bool dpu_encoder_is_widebus_enabled(struct drm_encoder *drm_enc)
> +{
> +       struct dpu_encoder_virt *dpu_enc = to_dpu_encoder_virt(drm_enc);
> +
> +       return dpu_enc->wide_bus_en;
> +}
> +
>  static void _dpu_encoder_setup_dither(struct dpu_hw_pingpong *hw_pp, unsigned bpc)
>  {
>         struct dpu_hw_dither_cfg dither_cfg = { 0 };
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
> index 99a5d73..893d74d 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
> @@ -168,4 +168,6 @@ int dpu_encoder_get_linecount(struct drm_encoder *drm_enc);
>   */
>  int dpu_encoder_get_frame_count(struct drm_encoder *drm_enc);
>
> +bool dpu_encoder_is_widebus_enabled(struct drm_encoder *drm_enc);
> +
>  #endif /* __DPU_ENCODER_H__ */
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c
> index 185379b..2af2bb7 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c
> @@ -110,6 +110,20 @@ static void drm_mode_to_intf_timing_params(
>                 timing->v_back_porch += timing->v_front_porch;
>                 timing->v_front_porch = 0;
>         }
> +
> +       timing->wide_bus_en = dpu_encoder_is_widebus_enabled(phys_enc->parent);
> +
> +       /*
> +        * for DP, divide the horizonal parameters by 2 when
> +        * widebus is enabled
> +        */
> +       if (phys_enc->hw_intf->cap->type == INTF_DP && timing->wide_bus_en) {
> +               timing->width = timing->width >> 1;
> +               timing->xres = timing->xres >> 1;
> +               timing->h_back_porch = timing->h_back_porch >> 1;
> +               timing->h_front_porch = timing->h_front_porch >> 1;
> +               timing->hsync_pulse_width = timing->hsync_pulse_width >> 1;
> +       }
>  }
>
>  static u32 get_horizontal_total(const struct intf_timing_params *timing)
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> index c2cd185..4e4fa56 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> @@ -33,6 +33,7 @@
>  #define INTF_TP_COLOR1                  0x05C
>  #define INTF_CONFIG2                    0x060
>  #define INTF_DISPLAY_DATA_HCTL          0x064
> +#define INTF_ACTIVE_DATA_HCTL           0x068
>  #define INTF_FRAME_LINE_COUNT_EN        0x0A8
>  #define INTF_FRAME_COUNT                0x0AC
>  #define   INTF_LINE_COUNT               0x0B0
> @@ -96,15 +97,23 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *ctx,
>         u32 hsync_period, vsync_period;
>         u32 display_v_start, display_v_end;
>         u32 hsync_start_x, hsync_end_x;
> +       u32 hsync_data_start_x, hsync_data_end_x;
>         u32 active_h_start, active_h_end;
>         u32 active_v_start, active_v_end;
>         u32 active_hctl, display_hctl, hsync_ctl;
>         u32 polarity_ctl, den_polarity, hsync_polarity, vsync_polarity;
>         u32 panel_format;
> -       u32 intf_cfg, intf_cfg2 = 0, display_data_hctl = 0;
> +       u32 intf_cfg, intf_cfg2 = 0;
> +       u32 display_data_hctl = 0, active_data_hctl = 0;
> +       u32 data_width;
> +       bool dp_intf = false;
>
>         /* read interface_cfg */
>         intf_cfg = DPU_REG_READ(c, INTF_CONFIG);
> +
> +       if (ctx->cap->type == INTF_EDP || ctx->cap->type == INTF_DP)
> +               dp_intf = true;
> +
>         hsync_period = p->hsync_pulse_width + p->h_back_porch + p->width +
>         p->h_front_porch;
>         vsync_period = p->vsync_pulse_width + p->v_back_porch + p->height +
> @@ -118,7 +127,7 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *ctx,
>         hsync_start_x = p->h_back_porch + p->hsync_pulse_width;
>         hsync_end_x = hsync_period - p->h_front_porch - 1;
>
> -       if (p->width != p->xres) {
> +       if (p->width != p->xres) { /* border fill added */
>                 active_h_start = hsync_start_x;
>                 active_h_end = active_h_start + p->xres - 1;
>         } else {
> @@ -126,7 +135,7 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *ctx,
>                 active_h_end = 0;
>         }
>
> -       if (p->height != p->yres) {
> +       if (p->height != p->yres) { /* border fill added */
>                 active_v_start = display_v_start;
>                 active_v_end = active_v_start + (p->yres * hsync_period) - 1;
>         } else {
> @@ -147,17 +156,36 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *ctx,
>         hsync_ctl = (hsync_period << 16) | p->hsync_pulse_width;
>         display_hctl = (hsync_end_x << 16) | hsync_start_x;
>
> -       if (ctx->cap->type == INTF_EDP || ctx->cap->type == INTF_DP) {
> +       /*
> +        * DATA_HCTL_EN controls data timing which can be different from
> +        * video timing. It is recommended to enable it for all cases, except
> +        * if compression is enabled in 1 pixel per clock mode
> +        */
> +       if (p->wide_bus_en)
> +               intf_cfg2 |= (INTF_CFG2_DATABUS_WIDEN | INTF_CFG2_DATA_HCTL_EN);
> +
> +       data_width = p->width;
> +
> +       hsync_data_start_x = hsync_start_x;
> +       hsync_data_end_x =  hsync_start_x + data_width - 1;
> +
> +       display_data_hctl = (hsync_data_end_x << 16) | hsync_data_start_x;
> +
> +       if (dp_intf) {
> +               /* DP timing adjustment */
> +               display_v_start += p->hsync_pulse_width + p->h_back_porch;
> +               display_v_end   -= p->h_front_porch;
> +
>                 active_h_start = hsync_start_x;
>                 active_h_end = active_h_start + p->xres - 1;
>                 active_v_start = display_v_start;
>                 active_v_end = active_v_start + (p->yres * hsync_period) - 1;
>
> -               display_v_start += p->hsync_pulse_width + p->h_back_porch;
> -               display_v_end   -= p->h_front_porch;
> -
>                 active_hctl = (active_h_end << 16) | active_h_start;
>                 display_hctl = active_hctl;
> +
> +               intf_cfg |= INTF_CFG_ACTIVE_H_EN;
> +               intf_cfg |= INTF_CFG_ACTIVE_V_EN;
>         }
>
>         den_polarity = 0;
> @@ -187,13 +215,6 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *ctx,
>                                 (COLOR_8BIT << 4) |
>                                 (0x21 << 8));
>
> -       if (ctx->cap->features & BIT(DPU_DATA_HCTL_EN)) {
> -               intf_cfg2 |= INTF_CFG2_DATA_HCTL_EN;
> -               display_data_hctl = display_hctl;
> -               DPU_REG_WRITE(c, INTF_CONFIG2, intf_cfg2);
> -               DPU_REG_WRITE(c, INTF_DISPLAY_DATA_HCTL, display_data_hctl);
> -       }
> -
>         DPU_REG_WRITE(c, INTF_HSYNC_CTL, hsync_ctl);
>         DPU_REG_WRITE(c, INTF_VSYNC_PERIOD_F0, vsync_period * hsync_period);
>         DPU_REG_WRITE(c, INTF_VSYNC_PULSE_WIDTH_F0,
> @@ -211,6 +232,11 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *ctx,
>         DPU_REG_WRITE(c, INTF_FRAME_LINE_COUNT_EN, 0x3);
>         DPU_REG_WRITE(c, INTF_CONFIG, intf_cfg);
>         DPU_REG_WRITE(c, INTF_PANEL_FORMAT, panel_format);
> +       if (ctx->cap->features & BIT(DPU_DATA_HCTL_EN)) {
> +               DPU_REG_WRITE(c, INTF_CONFIG2, intf_cfg2);
> +               DPU_REG_WRITE(c, INTF_DISPLAY_DATA_HCTL, display_data_hctl);
> +               DPU_REG_WRITE(c, INTF_ACTIVE_DATA_HCTL, active_data_hctl);
> +       }
>  }
>
>  static void dpu_hw_intf_enable_timing_engine(
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.h
> index 3568be8..e4a518a 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.h
> @@ -30,6 +30,8 @@ struct intf_timing_params {
>         u32 border_clr;
>         u32 underflow_clr;
>         u32 hsync_skew;
> +
> +       bool wide_bus_en;
>  };
>
>  struct intf_prog_fetch {
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>


-- 
With best wishes
Dmitry


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