Hi Uma Shankar,
Thanks for the comments and suggestions.
Please find my response inline.
On 12/13/2020 12:40 PM, Shankar, Uma wrote:
-----Original Message----- From: Nautiyal, Ankit K ankit.k.nautiyal@intel.com Sent: Tuesday, December 8, 2020 1:22 PM 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 v4 07/16] 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.
Signed-off-by: Ankit Nautiyal ankit.k.nautiyal@intel.com
drivers/gpu/drm/drm_dp_helper.c | 59 +++++++++++++++++++++++++++++++++ include/drm/drm_dp_helper.h | 10 +++++- 2 files changed, 68 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index d0626f57f99c..344662d5c295 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -949,6 +949,35 @@ 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
- Returns: whether the downstream facing port can convert RGB->YCbCr
+*/ bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8 +dpcd[DP_RECEIVER_CAP_SIZE],
const u8 port_cap[4])+{
- 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] & DP_DS_HDMI_BT601_RGB_YCBCR_CONV;I guess there are other conversions also possible, like BT709 and 2020. Update those as well here.
Yes you are right. I will modify the function to take as input colorspace, also and
the function will be returning true, if the rgb->ycbcr conversion for the given colorspace is supported.
- 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
@@ -3140,3 +3169,33 @@ 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 conversion type
- 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;
- if (color_spc != DP_CONVERSION_BT601_RGB_YCBCR_ENABLE ||
color_spc != DP_CONVERSION_BT709_RGB_YCBCR_ENABLE ||color_spc != DP_CONVERSION_BT2020_RGB_YCBCR_ENABLE)return -EINVAL;Yeah this is wrong, fix it.
Agreed. Will fix this in next version of the patch.
- ret = drm_dp_dpcd_readb(aux, DP_PROTOCOL_CONVERTER_CONTROL_2,
&buf);
- if (ret < 0)
return ret;- buf |= color_spc;
- 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 347b4e1a55b4..1b3d54ed7a78 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -431,6 +431,9 @@ struct drm_device; # define DP_DS_HDMI_YCBCR420_PASS_THROUGH (1 << 2) # define DP_DS_HDMI_YCBCR444_TO_422_CONV (1 << 3) # define DP_DS_HDMI_YCBCR444_TO_420_CONV (1 << 4) +# 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)
I think it would be good to mention the location in spec (section or table), will make it easier to understand/review by directly going to relevant sections in spec.
This is still Draft 1 of the spec: VESA DP-to-HDMI PCON Specification Standalone Document. Link in the commit message.
I will mention the current Section and Table no. nevertheless in the next version of the patch.
Thanks & Regards,
Ankit
#define DP_MAX_DOWNSTREAM_PORTS 0x10
@@ -1217,7 +1220,9 @@ 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_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 @@ -2178,5 +2183,8 @@ 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]);+int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 +color_spc);
#endif /* _DRM_DP_HELPER_H_ */
2.17.1