[Intel-gfx] [PATCH 1/2] drm/i915: Parse DSI backlight/cabc ports.

[Jani Nikula]

On Tue, 03 Oct 2017, Madhav Chauhan <madhav.chauhan at intel.com> wrote:
> This patch parse DSI backlight/cabc ports info from
> VBT and save them inside local strucutre. This saved info
> can be directly used while initializing DSI for different
> platforms instead of parsing for each platform.
>
> Signed-off-by: Madhav Chauhan <madhav.chauhan at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.h   |  2 ++
>  drivers/gpu/drm/i915/intel_bios.c | 63 ++++++++++++++++++++++++++++++++-------
>  2 files changed, 55 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index b7cba89..fc472bb 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1751,6 +1751,8 @@ struct intel_vbt_data {
>  		u8 seq_version;
>  		u32 size;
>  		u8 *data;
> +		u16 bl_ports;
> +		u16 cabc_ports;

This is right in the middle of the sequence data. Please move up
e.g. between pps and seq_version.

>  		const u8 *sequence[MIPI_SEQ_MAX];
>  	} dsi;
>  
> diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
> index 3747d8d..88a72cc 100644
> --- a/drivers/gpu/drm/i915/intel_bios.c
> +++ b/drivers/gpu/drm/i915/intel_bios.c
> @@ -730,6 +730,56 @@ parse_psr(struct drm_i915_private *dev_priv, const struct bdb_header *bdb)
>  	dev_priv->vbt.psr.tp2_tp3_wakeup_time = psr_table->tp2_tp3_wakeup_time;
>  }
>  
> +static void parse_dsi_backlight_ports(struct drm_i915_private *dev_priv,
> +				      u16 version, enum port port)
> +{
> +	if (dev_priv->vbt.dsi.config->dual_link && version < 197) {
> +		/*
> +		 * These fields are introduced from the VBT version 197 onwards,
> +		 * so making sure that these bits are set zero in the previous
> +		 * versions.
> +		 */
> +		dev_priv->vbt.dsi.config->dl_dcs_cabc_ports = 0;
> +		dev_priv->vbt.dsi.config->dl_dcs_backlight_ports = 0;

You could remove this in patch 2. Nobody should be looking at it
anymore.

> +		dev_priv->vbt.dsi.bl_ports = 0;
> +		dev_priv->vbt.dsi.cabc_ports = 0;

This you don't have to do anyway, it's all zeros by default.

> +		return;
> +	} else if (dev_priv->vbt.dsi.config->dual_link) {
> +		switch (dev_priv->vbt.dsi.config->dl_dcs_backlight_ports) {
> +		case DL_DCS_PORT_A:
> +			dev_priv->vbt.dsi.bl_ports = BIT(PORT_A);
> +			break;
> +		case DL_DCS_PORT_C:
> +			dev_priv->vbt.dsi.bl_ports = BIT(PORT_C);
> +			break;
> +		default:
> +		case DL_DCS_PORT_A_AND_C:
> +			dev_priv->vbt.dsi.bl_ports = BIT(PORT_A) | BIT(PORT_C);
> +			break;
> +		}
> +
> +		switch (dev_priv->vbt.dsi.config->dl_dcs_cabc_ports) {
> +		case DL_DCS_PORT_A:
> +			dev_priv->vbt.dsi.cabc_ports = BIT(PORT_A);
> +			break;
> +		case DL_DCS_PORT_C:
> +			dev_priv->vbt.dsi.cabc_ports = BIT(PORT_C);
> +			break;
> +		default:
> +		case DL_DCS_PORT_A_AND_C:
> +			dev_priv->vbt.dsi.cabc_ports =
> +						BIT(PORT_A) | BIT(PORT_C);
> +			break;
> +		}
> +	} else {
> +		dev_priv->vbt.dsi.bl_ports = BIT(port);
> +		dev_priv->vbt.dsi.cabc_ports = BIT(port);
> +	}
> +
> +	if (!dev_priv->vbt.dsi.config->cabc_supported)
> +		dev_priv->vbt.dsi.cabc_ports = 0;

Would seem reasonable to not initalize it in the first place if it's not
supported. If you do a series of early returns starting with the bdb
version check, then !dual_link, then !cabc_supported, it might be
easiest.

> +}
> +
>  static void
>  parse_mipi_config(struct drm_i915_private *dev_priv,
>  		  const struct bdb_header *bdb)
> @@ -738,9 +788,10 @@ parse_mipi_config(struct drm_i915_private *dev_priv,
>  	const struct mipi_config *config;
>  	const struct mipi_pps_data *pps;
>  	int panel_type = dev_priv->vbt.panel_type;
> +	enum port port;
>  
>  	/* parse MIPI blocks only if LFP type is MIPI */
> -	if (!intel_bios_is_dsi_present(dev_priv, NULL))
> +	if (!intel_bios_is_dsi_present(dev_priv, &port))
>  		return;
>  
>  	/* Initialize this to undefined indicating no generic MIPI support */
> @@ -781,15 +832,7 @@ parse_mipi_config(struct drm_i915_private *dev_priv,
>  		return;
>  	}
>  
> -	/*
> -	 * These fields are introduced from the VBT version 197 onwards,
> -	 * so making sure that these bits are set zero in the previous
> -	 * versions.
> -	 */
> -	if (dev_priv->vbt.dsi.config->dual_link && bdb->version < 197) {
> -		dev_priv->vbt.dsi.config->dl_dcs_cabc_ports = 0;
> -		dev_priv->vbt.dsi.config->dl_dcs_backlight_ports = 0;
> -	}
> +	parse_dsi_backlight_ports(dev_priv, bdb->version, port);
>  
>  	/* We have mandatory mipi config blocks. Initialize as generic panel */
>  	dev_priv->vbt.dsi.panel_id = MIPI_DSI_GENERIC_PANEL_ID;

-- 
Jani Nikula, Intel Open Source Technology Center