Re: [PATCH v4 2/2] drm/msm/dp: enable widebus feature for display port

[Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>]

On 2/15/2022 5:34 AM, Dmitry Baryshkov wrote:
> On 15/02/2022 01:39, Kuogee Hsieh wrote:
> > Widebus feature will transmit two pixel data per pixel clock to 
> > interface.
> > This feature now is required to be enabled to easy migrant to higher
> > resolution applications in future. However since some legacy chipsets
> > does not support this feature, this feature is enabled base on chip's
> > hardware revision.
> >
> > 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
> > -- enable widebus feature base on chip hardware revision
> >
> > Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
> > ---
> >   drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c |  4 +++-
> >   drivers/gpu/drm/msm/dp/dp_catalog.c         | 36 
> > +++++++++++++++++++++++++++--
> >   drivers/gpu/drm/msm/dp/dp_catalog.h         |  3 ++-
> >   drivers/gpu/drm/msm/dp/dp_ctrl.c            | 13 +++++++----
> >   drivers/gpu/drm/msm/dp/dp_ctrl.h            |  1 +
> >   drivers/gpu/drm/msm/dp/dp_display.c         | 30 
> > ++++++++++++++++++++++++
> >   drivers/gpu/drm/msm/dp/dp_display.h         |  2 ++
> >   drivers/gpu/drm/msm/dp/dp_panel.c           |  4 ++--
> >   drivers/gpu/drm/msm/dp/dp_panel.h           |  2 +-
> >   drivers/gpu/drm/msm/msm_drv.h               |  6 +++++
> >   10 files changed, 90 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c 
> > b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > index 0c22839..b2d23c2 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > @@ -2167,8 +2167,10 @@ int dpu_encoder_setup(struct drm_device *dev, 
> > struct drm_encoder *enc,
> >           timer_setup(&dpu_enc->vsync_event_timer,
> >                   dpu_encoder_vsync_event_handler,
> >                   0);
> > -    else if (disp_info->intf_type == DRM_MODE_ENCODER_TMDS)
> > +    else if (disp_info->intf_type == DRM_MODE_ENCODER_TMDS) {
> >           dpu_enc->dp = priv->dp[disp_info->h_tile_instance[0]];
> > +        dpu_enc->wide_bus_en = msm_dp_wide_bus_enable(dpu_enc->dp);
> > +    }
>
> Please revert the order of the patches and move this chunk into the 
> DPU patch.

There is chicken  and egg issue here.

I think we should create an communication channel to pass dp/dsi driver 
info to drm, such as wide_bus_en and dsc compression, etc.

By function calls like this will create more unnecessary tangles between 
driver and drm layer.

> > INIT_DELAYED_WORK(&dpu_enc->delayed_off_work,
> >               dpu_encoder_off_work);
> > diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.c 
> > b/drivers/gpu/drm/msm/dp/dp_catalog.c
> > index 64f0b26..99d087e 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_catalog.c
> > +++ b/drivers/gpu/drm/msm/dp/dp_catalog.c
> > @@ -483,6 +483,27 @@ int dp_catalog_ctrl_set_pattern_state_bit(struct 
> > dp_catalog *dp_catalog,
> >   }
> >     /**
> > + * dp_catalog_hw_revision() - retrieve DP hw revision
> > + *
> > + * @dp_catalog: DP catalog structure
> > + *
> > + * return: u32
> > + *
> > + * This function return the DP controller hw revision
> > + *
> > + */
> > +u32 dp_catalog_hw_revision(struct dp_catalog *dp_catalog)
> > +{
> > +    u32 revision;
> > +    struct dp_catalog_private *catalog = container_of(dp_catalog,
> > +                struct dp_catalog_private, dp_catalog);
> > +
> > +    revision = dp_read_ahb(catalog, REG_DP_HW_VERSION);
> > +
> > +    return revision;
> > +}
> > +
> > +/**
> >    * dp_catalog_ctrl_reset() - reset DP controller
> >    *
> >    * @dp_catalog: DP catalog structure
> > @@ -739,10 +760,11 @@ u32 dp_catalog_ctrl_read_phy_pattern(struct 
> > dp_catalog *dp_catalog)
> >   }
> >     /* panel related catalog functions */
> > -int dp_catalog_panel_timing_cfg(struct dp_catalog *dp_catalog)
> > +int dp_catalog_panel_timing_cfg(struct dp_catalog *dp_catalog, bool 
> > wide_bus_en)
> >   {
> >       struct dp_catalog_private *catalog = container_of(dp_catalog,
> >                   struct dp_catalog_private, dp_catalog);
> > +    u32 reg;
> >         dp_write_link(catalog, REG_DP_TOTAL_HOR_VER,
> >                   dp_catalog->total);
> > @@ -751,7 +773,17 @@ int dp_catalog_panel_timing_cfg(struct 
> > dp_catalog *dp_catalog)
> >       dp_write_link(catalog, REG_DP_HSYNC_VSYNC_WIDTH_POLARITY,
> >                   dp_catalog->width_blanking);
> >       dp_write_link(catalog, REG_DP_ACTIVE_HOR_VER, 
> > dp_catalog->dp_active);
> > -    dp_write_p0(catalog, MMSS_DP_INTF_CONFIG, 0);
> > +
> > +    reg = dp_read_p0(catalog, MMSS_DP_INTF_CONFIG);
> > +
> > +    if (wide_bus_en)
> > +        reg |= BIT(4);    /* DATABUS_WIDEN */
> > +    else
> > +        reg &= ~BIT(4);
> > +
> > +    DRM_DEBUG_DP("wide_bus_en=%d reg=%x\n", wide_bus_en, reg);
> > +
> > +    dp_write_p0(catalog, MMSS_DP_INTF_CONFIG, reg);
> >       return 0;
> >   }
> >   diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.h 
> > b/drivers/gpu/drm/msm/dp/dp_catalog.h
> > index 7dea101..a3a0129 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_catalog.h
> > +++ b/drivers/gpu/drm/msm/dp/dp_catalog.h
> > @@ -95,6 +95,7 @@ void dp_catalog_ctrl_config_misc(struct dp_catalog 
> > *dp_catalog, u32 cc, u32 tb);
> >   void dp_catalog_ctrl_config_msa(struct dp_catalog *dp_catalog, u32 
> > rate,
> >                   u32 stream_rate_khz, bool fixed_nvid);
> >   int dp_catalog_ctrl_set_pattern_state_bit(struct dp_catalog 
> > *dp_catalog, u32 pattern);
> > +u32 dp_catalog_hw_revision(struct dp_catalog *dp_catalog);
> >   void dp_catalog_ctrl_reset(struct dp_catalog *dp_catalog);
> >   bool dp_catalog_ctrl_mainlink_ready(struct dp_catalog *dp_catalog);
> >   void dp_catalog_ctrl_enable_irq(struct dp_catalog *dp_catalog, bool 
> > enable);
> > @@ -115,7 +116,7 @@ void dp_catalog_ctrl_send_phy_pattern(struct 
> > dp_catalog *dp_catalog,
> >   u32 dp_catalog_ctrl_read_phy_pattern(struct dp_catalog *dp_catalog);
> >     /* DP Panel APIs */
> > -int dp_catalog_panel_timing_cfg(struct dp_catalog *dp_catalog);
> > +int dp_catalog_panel_timing_cfg(struct dp_catalog *dp_catalog, bool 
> > wide_bus_en);
> >   void dp_catalog_dump_regs(struct dp_catalog *dp_catalog);
> >   void dp_catalog_panel_tpg_enable(struct dp_catalog *dp_catalog,
> >                   struct drm_display_mode *drm_mode);
> > diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c 
> > b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> > index 245e1b9..1c4cf9d 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
> > +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> > @@ -154,7 +154,7 @@ static void dp_ctrl_config_ctrl(struct 
> > dp_ctrl_private *ctrl)
> >       dp_catalog_ctrl_config_ctrl(ctrl->catalog, config);
> >   }
> >   -static void dp_ctrl_configure_source_params(struct dp_ctrl_private 
> > *ctrl)
> > +static void dp_ctrl_configure_source_params(struct dp_ctrl_private 
> > *ctrl, bool wide_bus_en)
> >   {
> >       u32 cc, tb;
> >   @@ -167,7 +167,7 @@ static void 
> > dp_ctrl_configure_source_params(struct dp_ctrl_private *ctrl)
> >           ctrl->panel->dp_mode.bpp);
> >       cc = dp_link_get_colorimetry_config(ctrl->link);
> >       dp_catalog_ctrl_config_misc(ctrl->catalog, cc, tb);
> > -    dp_panel_timing_cfg(ctrl->panel);
> > +    dp_panel_timing_cfg(ctrl->panel, wide_bus_en);
> >   }
> >     /*
> > @@ -1796,6 +1796,7 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl)
> >       int ret = 0;
> >       bool mainlink_ready = false;
> >       struct dp_ctrl_private *ctrl;
> > +    u32 pixel_rate_orig;
> >         if (!dp_ctrl)
> >           return -EINVAL;
> > @@ -1804,6 +1805,10 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl)
> >         ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
> >   +    pixel_rate_orig = ctrl->dp_ctrl.pixel_rate;
> > +    if (dp_ctrl->wide_bus_en)
> > +        ctrl->dp_ctrl.pixel_rate >>= 1;
> > +
> >       DRM_DEBUG_DP("rate=%d, num_lanes=%d, pixel_rate=%d\n",
> >           ctrl->link->link_params.rate,
> >           ctrl->link->link_params.num_lanes, ctrl->dp_ctrl.pixel_rate);
> > @@ -1839,11 +1844,11 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl)
> >        */
> >       reinit_completion(&ctrl->video_comp);
> >   -    dp_ctrl_configure_source_params(ctrl);
> > +    dp_ctrl_configure_source_params(ctrl, dp_ctrl->wide_bus_en);
> >         dp_catalog_ctrl_config_msa(ctrl->catalog,
> >           ctrl->link->link_params.rate,
> > -        ctrl->dp_ctrl.pixel_rate, dp_ctrl_use_fixed_nvid(ctrl));
> > +        pixel_rate_orig, dp_ctrl_use_fixed_nvid(ctrl));
> >         dp_ctrl_setup_tr_unit(ctrl);
> >   diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.h 
> > b/drivers/gpu/drm/msm/dp/dp_ctrl.h
> > index 2433edb..4dff44d 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_ctrl.h
> > +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.h
> > @@ -17,6 +17,7 @@ struct dp_ctrl {
> >       bool orientation;
> >       atomic_t aborted;
> >       u32 pixel_rate;
> > +    bool wide_bus_en;
> >   };
> >     int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl);
> > diff --git a/drivers/gpu/drm/msm/dp/dp_display.c 
> > b/drivers/gpu/drm/msm/dp/dp_display.c
> > index e89556ad..d45a3aa 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_display.c
> > +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> > @@ -117,6 +117,8 @@ struct dp_display_private {
> >       struct dp_event event_list[DP_EVENT_Q_MAX];
> >       spinlock_t event_lock;
> >   +    bool wide_bus_en;
> > +
> >       struct dp_audio *audio;
> >   };
> >   @@ -845,6 +847,8 @@ static int dp_display_enable(struct 
> > dp_display_private *dp, u32 data)
> >           return 0;
> >       }
> >   +    dp->ctrl->wide_bus_en = dp->wide_bus_en;
> > +
> >       rc = dp_ctrl_on_stream(dp->ctrl);
> >       if (!rc)
> >           dp_display->power_on = true;
> > @@ -979,6 +983,7 @@ int dp_display_get_modes(struct msm_dp *dp,
> >           dp->connector, dp_mode);
> >       if (dp_mode->drm_mode.clock)
> >           dp->max_pclk_khz = dp_mode->drm_mode.clock;
> > +
> >       return ret;
> >   }
> >   @@ -1451,6 +1456,28 @@ void msm_dp_irq_postinstall(struct msm_dp 
> > *dp_display)
> >       }
> >   }
> >   +bool msm_dp_wide_bus_enable(struct msm_dp *dp_display)
> > +{
> > +    struct dp_display_private *dp;
> > +    u32 revision, major, minor;
> > +
> > +    dp = container_of(dp_display, struct dp_display_private, 
> > dp_display);
> > +
> > +    /* for the time being widebus only support on DP */
> > +    if (dp_display->connector_type  == 
> > DRM_MODE_CONNECTOR_DisplayPort) {
> > +        revision = dp_catalog_hw_revision(dp->catalog);
> > +        major = ((revision >> 28) & 0x0ff);
> > +        minor = ((revision >> 16) & 0x0fff);
> > +
> > +    DRM_DEBUG_DP("id=%d major=%d minor=%d\n", dp->id, major, minor);
> > +
> > +        if (major >= 1 && minor >= 2)
> > +            return true;
> > +    }
> > +
> > +    return false;
> > +}
> > +
> >   void msm_dp_debugfs_init(struct msm_dp *dp_display, struct 
> > drm_minor *minor)
> >   {
> >       struct dp_display_private *dp;
> > @@ -1505,6 +1532,9 @@ int msm_dp_modeset_init(struct msm_dp 
> > *dp_display, struct drm_device *dev,
> >       dp_priv->panel->connector = dp_display->connector;
> >         priv->connectors[priv->num_connectors++] = 
> > dp_display->connector;
> > +
> > +    dp_priv->wide_bus_en = msm_dp_wide_bus_enable(dp_display);
> > +
> >       return 0;
> >   }
> >   diff --git a/drivers/gpu/drm/msm/dp/dp_display.h 
> > b/drivers/gpu/drm/msm/dp/dp_display.h
> > index 8e80e3b..d9cb9ee 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_display.h
> > +++ b/drivers/gpu/drm/msm/dp/dp_display.h
> > @@ -23,6 +23,8 @@ struct msm_dp {
> >         hdmi_codec_plugged_cb plugged_cb;
> >   +    bool wide_bus_en;
> > +
> >       u32 max_pclk_khz;
> >         u32 max_dp_lanes;
> > diff --git a/drivers/gpu/drm/msm/dp/dp_panel.c 
> > b/drivers/gpu/drm/msm/dp/dp_panel.c
> > index 71db10c..71deb1e 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_panel.c
> > +++ b/drivers/gpu/drm/msm/dp/dp_panel.c
> > @@ -353,7 +353,7 @@ void dp_panel_dump_regs(struct dp_panel *dp_panel)
> >       dp_catalog_dump_regs(catalog);
> >   }
> >   -int dp_panel_timing_cfg(struct dp_panel *dp_panel)
> > +int dp_panel_timing_cfg(struct dp_panel *dp_panel, bool wide_bus_en)
> >   {
> >       u32 data, total_ver, total_hor;
> >       struct dp_catalog *catalog;
> > @@ -404,7 +404,7 @@ int dp_panel_timing_cfg(struct dp_panel *dp_panel)
> >         catalog->dp_active = data;
> >   -    dp_catalog_panel_timing_cfg(catalog);
> > +    dp_catalog_panel_timing_cfg(catalog, wide_bus_en);
> >       panel->panel_on = true;
> >         return 0;
> > diff --git a/drivers/gpu/drm/msm/dp/dp_panel.h 
> > b/drivers/gpu/drm/msm/dp/dp_panel.h
> > index 9023e5b..5ec341a 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_panel.h
> > +++ b/drivers/gpu/drm/msm/dp/dp_panel.h
> > @@ -57,7 +57,7 @@ struct dp_panel {
> >     int dp_panel_init_panel_info(struct dp_panel *dp_panel);
> >   int dp_panel_deinit(struct dp_panel *dp_panel);
> > -int dp_panel_timing_cfg(struct dp_panel *dp_panel);
> > +int dp_panel_timing_cfg(struct dp_panel *dp_panel, bool wide_bus_en);
> >   void dp_panel_dump_regs(struct dp_panel *dp_panel);
> >   int dp_panel_read_sink_caps(struct dp_panel *dp_panel,
> >           struct drm_connector *connector);
> > diff --git a/drivers/gpu/drm/msm/msm_drv.h 
> > b/drivers/gpu/drm/msm/msm_drv.h
> > index 07f6c41..667f3a8 100644
> > --- a/drivers/gpu/drm/msm/msm_drv.h
> > +++ b/drivers/gpu/drm/msm/msm_drv.h
> > @@ -398,6 +398,7 @@ void msm_dp_irq_postinstall(struct msm_dp 
> > *dp_display);
> >   void msm_dp_snapshot(struct msm_disp_state *disp_state, struct 
> > msm_dp *dp_display);
> >     void msm_dp_debugfs_init(struct msm_dp *dp_display, struct 
> > drm_minor *minor);
> > +bool msm_dp_wide_bus_enable(struct msm_dp *dp_display);
> >     #else
> >   static inline int __init msm_dp_register(void)
> > @@ -448,6 +449,11 @@ static inline void msm_dp_debugfs_init(struct 
> > msm_dp *dp_display,
> >   {
> >   }
> >   +bool msm_dp_wide_bus_enable(struct msm_dp *dp_display)
> > +{
> > +    return false;
> > +}
> > +
> >   #endif
> >     void __init msm_mdp_register(void);