diff mbox series

[v5,07/15] drm/dp_helper: Add helpers to configure PCONs RGB-YCbCr Conversion

Message ID 20201216053121.18819-8-ankit.k.nautiyal@intel.com (mailing list archive)
State New, archived
Headers show
Series Add support for DP-HDMI2.1 PCON | expand

Commit Message

Nautiyal, Ankit K Dec. 16, 2020, 5:31 a.m. UTC
DP Specification for DP2.0 to HDMI2.1 Pcon specifies support for conversion
of colorspace from RGB to YCbCr.
https://groups.vesa.org/wg/DP/document/previewpdf/15651

This patch adds the relavant registers and helper functions to
get the capability and set the color conversion bits for rgb->ycbcr
conversion through PCON.

v2: As suggested in review comments:
-Fixed bug in the check condition in a drm_helper as reported by
 Dan Carpenter and Kernel test robot. (Dan Carepenter)
-Modified the color-conversion cap helper function, to accomodate
 BT709 and BT2020 colorspace. (Uma Shankar)
-Added spec details for the new cap for color conversion. (Uma Shankar)

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
---
 drivers/gpu/drm/drm_dp_helper.c | 61 +++++++++++++++++++++++++++++++++
 include/drm/drm_dp_helper.h     | 19 +++++++++-
 2 files changed, 79 insertions(+), 1 deletion(-)

Comments

Shankar, Uma Dec. 16, 2020, 7:15 p.m. UTC | #1
> -----Original Message-----
> From: Nautiyal, Ankit K <ankit.k.nautiyal@intel.com>
> Sent: Wednesday, December 16, 2020 11:01 AM
> To: intel-gfx@lists.freedesktop.org
> Cc: dri-devel@lists.freedesktop.org; Shankar, Uma <uma.shankar@intel.com>;
> airlied@linux.ie; jani.nikula@linux.intel.com; ville.syrjala@linux.intel.com;
> Kulkarni, Vandita <vandita.kulkarni@intel.com>; Sharma, Swati2
> <swati2.sharma@intel.com>
> Subject: [PATCH v5 07/15] drm/dp_helper: Add helpers to configure PCONs RGB-
> YCbCr Conversion
> 
> DP Specification for DP2.0 to HDMI2.1 Pcon specifies support for conversion of
> colorspace from RGB to YCbCr.
> https://groups.vesa.org/wg/DP/document/previewpdf/15651
> 
> This patch adds the relavant registers and helper functions to get the capability
> and set the color conversion bits for rgb->ycbcr conversion through PCON.
> 
> v2: As suggested in review comments:
> -Fixed bug in the check condition in a drm_helper as reported by  Dan Carpenter
> and Kernel test robot. (Dan Carepenter) -Modified the color-conversion cap
> helper function, to accomodate
>  BT709 and BT2020 colorspace. (Uma Shankar) -Added spec details for the new
> cap for color conversion. (Uma Shankar)

Looks Good to me.
Reviewed-by: Uma Shankar <uma.shankar@intel.com>

> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> ---
>  drivers/gpu/drm/drm_dp_helper.c | 61 +++++++++++++++++++++++++++++++++
>  include/drm/drm_dp_helper.h     | 19 +++++++++-
>  2 files changed, 79 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/drm_dp_helper.c
> b/drivers/gpu/drm/drm_dp_helper.c index 689fd0d5f6c5..9abd65c694ab 100644
> --- a/drivers/gpu/drm/drm_dp_helper.c
> +++ b/drivers/gpu/drm/drm_dp_helper.c
> @@ -949,6 +949,38 @@ bool
> drm_dp_downstream_444_to_420_conversion(const u8
> dpcd[DP_RECEIVER_CAP_SIZE]  }
> EXPORT_SYMBOL(drm_dp_downstream_444_to_420_conversion);
> 
> +/**
> + * drm_dp_downstream_rgb_to_ycbcr_conversion() - determine downstream
> facing port
> + *                                               RGB->YCbCr conversion capability
> + * @dpcd: DisplayPort configuration data
> + * @port_cap: downstream facing port capabilities
> + * @colorspc: Colorspace for which conversion cap is sought
> + *
> + * Returns: whether the downstream facing port can convert RGB->YCbCr
> +for a given
> + * colorspace.
> + */
> +bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8
> dpcd[DP_RECEIVER_CAP_SIZE],
> +					       const u8 port_cap[4],
> +					       u8 color_spc)
> +{
> +	if (!drm_dp_is_branch(dpcd))
> +		return false;
> +
> +	if (dpcd[DP_DPCD_REV] < 0x13)
> +		return false;
> +
> +	switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) {
> +	case DP_DS_PORT_TYPE_HDMI:
> +		if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] &
> DP_DETAILED_CAP_INFO_AVAILABLE) == 0)
> +			return false;
> +
> +		return port_cap[3] & color_spc;
> +	default:
> +		return false;
> +	}
> +}
> +EXPORT_SYMBOL(drm_dp_downstream_rgb_to_ycbcr_conversion);
> +
>  /**
>   * drm_dp_downstream_mode() - return a mode for downstream facing port
>   * @dev: DRM device
> @@ -3101,3 +3133,32 @@ int drm_dp_pcon_pps_override_param(struct
> drm_dp_aux *aux, u8 pps_param[6])
>  	return 0;
>  }
>  EXPORT_SYMBOL(drm_dp_pcon_pps_override_param);
> +
> +/*
> + * drm_dp_pcon_convert_rgb_to_ycbcr() - Configure the PCon to convert
> +RGB to Ycbcr
> + * @aux: displayPort AUX channel
> + * @color_spc: Color-space/s for which conversion is to be enabled, 0 for
> disable.
> + *
> + * Returns 0 on success, else returns negative error code.
> + */
> +int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8
> +color_spc) {
> +	int ret;
> +	u8 buf;
> +
> +	ret = drm_dp_dpcd_readb(aux, DP_PROTOCOL_CONVERTER_CONTROL_2,
> &buf);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (color_spc & DP_CONVERSION_RGB_YCBCR_MASK)
> +		buf |= (color_spc & DP_CONVERSION_RGB_YCBCR_MASK);
> +	else
> +		buf &= ~DP_CONVERSION_RGB_YCBCR_MASK;
> +
> +	ret = drm_dp_dpcd_writeb(aux,
> DP_PROTOCOL_CONVERTER_CONTROL_2, buf);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(drm_dp_pcon_convert_rgb_to_ycbcr);
> diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index
> baad87fe6b0a..e096ee98842b 100644
> --- a/include/drm/drm_dp_helper.h
> +++ b/include/drm/drm_dp_helper.h
> @@ -432,6 +432,17 @@ struct drm_device;
>  # define DP_DS_HDMI_YCBCR444_TO_422_CONV    (1 << 3)
>  # define DP_DS_HDMI_YCBCR444_TO_420_CONV    (1 << 4)
> 
> +/*
> + * VESA DP-to-HDMI PCON Specification adds caps for colorspace
> + * conversion in DFP cap DPCD 83h. Sec6.1 Table-3.
> + * Based on the available support the source can enable
> + * color conversion by writing into PROTOCOL_COVERTER_CONTROL_2
> + * DPCD 3052h.
> + */
> +# define DP_DS_HDMI_BT601_RGB_YCBCR_CONV    (1 << 5)
> +# define DP_DS_HDMI_BT709_RGB_YCBCR_CONV    (1 << 6)
> +# define DP_DS_HDMI_BT2020_RGB_YCBCR_CONV   (1 << 7)
> +
>  #define DP_MAX_DOWNSTREAM_PORTS		    0x10
> 
>  /* DP Forward error Correction Registers */ @@ -1207,7 +1218,10 @@ struct
> drm_device;
>  # define DP_PCON_ENC_PPS_OVERRIDE_DISABLED      0
>  # define DP_PCON_ENC_PPS_OVERRIDE_EN_PARAMS     1
>  # define DP_PCON_ENC_PPS_OVERRIDE_EN_BUFFER     2
> -
> +# define DP_CONVERSION_RGB_YCBCR_MASK	       (7 << 4)
> +# define DP_CONVERSION_BT601_RGB_YCBCR_ENABLE  (1 << 4) # define
> +DP_CONVERSION_BT709_RGB_YCBCR_ENABLE  (1 << 5) # define
> +DP_CONVERSION_BT2020_RGB_YCBCR_ENABLE (1 << 6)
> 
>  /* PCON Downstream HDMI ERROR Status per Lane */
>  #define DP_PCON_HDMI_ERROR_STATUS_LN0          0x3037
> @@ -2167,5 +2181,8 @@ int drm_dp_pcon_dsc_bpp_incr(const u8
> pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE
>  int drm_dp_pcon_pps_default(struct drm_dp_aux *aux);  int
> drm_dp_pcon_pps_override_buf(struct drm_dp_aux *aux, u8 pps_buf[128]);  int
> drm_dp_pcon_pps_override_param(struct drm_dp_aux *aux, u8 pps_param[6]);
> +bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8
> dpcd[DP_RECEIVER_CAP_SIZE],
> +					       const u8 port_cap[4], u8 color_spc);
> int
> +drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 color_spc);
> 
>  #endif /* _DRM_DP_HELPER_H_ */
> --
> 2.17.1
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 689fd0d5f6c5..9abd65c694ab 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -949,6 +949,38 @@  bool drm_dp_downstream_444_to_420_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZE]
 }
 EXPORT_SYMBOL(drm_dp_downstream_444_to_420_conversion);
 
+/**
+ * drm_dp_downstream_rgb_to_ycbcr_conversion() - determine downstream facing port
+ *                                               RGB->YCbCr conversion capability
+ * @dpcd: DisplayPort configuration data
+ * @port_cap: downstream facing port capabilities
+ * @colorspc: Colorspace for which conversion cap is sought
+ *
+ * Returns: whether the downstream facing port can convert RGB->YCbCr for a given
+ * colorspace.
+ */
+bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
+					       const u8 port_cap[4],
+					       u8 color_spc)
+{
+	if (!drm_dp_is_branch(dpcd))
+		return false;
+
+	if (dpcd[DP_DPCD_REV] < 0x13)
+		return false;
+
+	switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) {
+	case DP_DS_PORT_TYPE_HDMI:
+		if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) == 0)
+			return false;
+
+		return port_cap[3] & color_spc;
+	default:
+		return false;
+	}
+}
+EXPORT_SYMBOL(drm_dp_downstream_rgb_to_ycbcr_conversion);
+
 /**
  * drm_dp_downstream_mode() - return a mode for downstream facing port
  * @dev: DRM device
@@ -3101,3 +3133,32 @@  int drm_dp_pcon_pps_override_param(struct drm_dp_aux *aux, u8 pps_param[6])
 	return 0;
 }
 EXPORT_SYMBOL(drm_dp_pcon_pps_override_param);
+
+/*
+ * drm_dp_pcon_convert_rgb_to_ycbcr() - Configure the PCon to convert RGB to Ycbcr
+ * @aux: displayPort AUX channel
+ * @color_spc: Color-space/s for which conversion is to be enabled, 0 for disable.
+ *
+ * Returns 0 on success, else returns negative error code.
+ */
+int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 color_spc)
+{
+	int ret;
+	u8 buf;
+
+	ret = drm_dp_dpcd_readb(aux, DP_PROTOCOL_CONVERTER_CONTROL_2, &buf);
+	if (ret < 0)
+		return ret;
+
+	if (color_spc & DP_CONVERSION_RGB_YCBCR_MASK)
+		buf |= (color_spc & DP_CONVERSION_RGB_YCBCR_MASK);
+	else
+		buf &= ~DP_CONVERSION_RGB_YCBCR_MASK;
+
+	ret = drm_dp_dpcd_writeb(aux, DP_PROTOCOL_CONVERTER_CONTROL_2, buf);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_dp_pcon_convert_rgb_to_ycbcr);
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index baad87fe6b0a..e096ee98842b 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -432,6 +432,17 @@  struct drm_device;
 # define DP_DS_HDMI_YCBCR444_TO_422_CONV    (1 << 3)
 # define DP_DS_HDMI_YCBCR444_TO_420_CONV    (1 << 4)
 
+/*
+ * VESA DP-to-HDMI PCON Specification adds caps for colorspace
+ * conversion in DFP cap DPCD 83h. Sec6.1 Table-3.
+ * Based on the available support the source can enable
+ * color conversion by writing into PROTOCOL_COVERTER_CONTROL_2
+ * DPCD 3052h.
+ */
+# define DP_DS_HDMI_BT601_RGB_YCBCR_CONV    (1 << 5)
+# define DP_DS_HDMI_BT709_RGB_YCBCR_CONV    (1 << 6)
+# define DP_DS_HDMI_BT2020_RGB_YCBCR_CONV   (1 << 7)
+
 #define DP_MAX_DOWNSTREAM_PORTS		    0x10
 
 /* DP Forward error Correction Registers */
@@ -1207,7 +1218,10 @@  struct drm_device;
 # define DP_PCON_ENC_PPS_OVERRIDE_DISABLED      0
 # define DP_PCON_ENC_PPS_OVERRIDE_EN_PARAMS     1
 # define DP_PCON_ENC_PPS_OVERRIDE_EN_BUFFER     2
-
+# define DP_CONVERSION_RGB_YCBCR_MASK	       (7 << 4)
+# define DP_CONVERSION_BT601_RGB_YCBCR_ENABLE  (1 << 4)
+# define DP_CONVERSION_BT709_RGB_YCBCR_ENABLE  (1 << 5)
+# define DP_CONVERSION_BT2020_RGB_YCBCR_ENABLE (1 << 6)
 
 /* PCON Downstream HDMI ERROR Status per Lane */
 #define DP_PCON_HDMI_ERROR_STATUS_LN0          0x3037
@@ -2167,5 +2181,8 @@  int drm_dp_pcon_dsc_bpp_incr(const u8 pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE
 int drm_dp_pcon_pps_default(struct drm_dp_aux *aux);
 int drm_dp_pcon_pps_override_buf(struct drm_dp_aux *aux, u8 pps_buf[128]);
 int drm_dp_pcon_pps_override_param(struct drm_dp_aux *aux, u8 pps_param[6]);
+bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
+					       const u8 port_cap[4], u8 color_spc);
+int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 color_spc);
 
 #endif /* _DRM_DP_HELPER_H_ */