diff mbox series

[08/17] drm/msm/dp: change YUV420 related programming for DP

Message ID 20240125193834.7065-9-quic_parellan@quicinc.com (mailing list archive)
State Superseded
Headers show
Series Add support for CDM over DP | expand

Commit Message

Paloma Arellano Jan. 25, 2024, 7:38 p.m. UTC
Change all relevant DP controller related programming for YUV420 cases.
Namely, change the pixel clock math to consider YUV420, program the
configuration control to indicate YUV420, as well as modify the MVID
programming to consider YUV420.

Signed-off-by: Paloma Arellano <quic_parellan@quicinc.com>
---
 drivers/gpu/drm/msm/dp/dp_catalog.c |  5 ++++-
 drivers/gpu/drm/msm/dp/dp_catalog.h |  2 +-
 drivers/gpu/drm/msm/dp/dp_ctrl.c    | 12 +++++++++---
 drivers/gpu/drm/msm/dp/dp_display.c |  8 +++++++-
 drivers/gpu/drm/msm/msm_kms.h       |  3 +++
 5 files changed, 24 insertions(+), 6 deletions(-)

Comments

Dmitry Baryshkov Jan. 25, 2024, 9:29 p.m. UTC | #1
On 25/01/2024 21:38, Paloma Arellano wrote:
> Change all relevant DP controller related programming for YUV420 cases.
> Namely, change the pixel clock math to consider YUV420, program the
> configuration control to indicate YUV420, as well as modify the MVID
> programming to consider YUV420.

Too many items for a single commit.

> 
> Signed-off-by: Paloma Arellano <quic_parellan@quicinc.com>
> ---
>   drivers/gpu/drm/msm/dp/dp_catalog.c |  5 ++++-
>   drivers/gpu/drm/msm/dp/dp_catalog.h |  2 +-
>   drivers/gpu/drm/msm/dp/dp_ctrl.c    | 12 +++++++++---
>   drivers/gpu/drm/msm/dp/dp_display.c |  8 +++++++-
>   drivers/gpu/drm/msm/msm_kms.h       |  3 +++
>   5 files changed, 24 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.c b/drivers/gpu/drm/msm/dp/dp_catalog.c
> index 5142aeb705a44..5d84c089e520a 100644
> --- a/drivers/gpu/drm/msm/dp/dp_catalog.c
> +++ b/drivers/gpu/drm/msm/dp/dp_catalog.c
> @@ -442,7 +442,7 @@ void dp_catalog_ctrl_config_misc(struct dp_catalog *dp_catalog,
>   
>   void dp_catalog_ctrl_config_msa(struct dp_catalog *dp_catalog,
>   					u32 rate, u32 stream_rate_khz,
> -					bool fixed_nvid)
> +					bool fixed_nvid, bool is_ycbcr_420)
>   {
>   	u32 pixel_m, pixel_n;
>   	u32 mvid, nvid, pixel_div = 0, dispcc_input_rate;
> @@ -485,6 +485,9 @@ void dp_catalog_ctrl_config_msa(struct dp_catalog *dp_catalog,
>   		nvid = temp;
>   	}
>   
> +	if (is_ycbcr_420)
> +		mvid /= 2;
> +
>   	if (link_rate_hbr2 == rate)
>   		nvid *= 2;
>   
> diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.h b/drivers/gpu/drm/msm/dp/dp_catalog.h
> index 38786e855b51a..6cb5e2a243de2 100644
> --- a/drivers/gpu/drm/msm/dp/dp_catalog.h
> +++ b/drivers/gpu/drm/msm/dp/dp_catalog.h
> @@ -96,7 +96,7 @@ void dp_catalog_ctrl_mainlink_ctrl(struct dp_catalog *dp_catalog, bool enable);
>   void dp_catalog_ctrl_psr_mainlink_enable(struct dp_catalog *dp_catalog, bool enable);
>   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);
> +				u32 stream_rate_khz, bool fixed_nvid, bool is_ycbcr_420);
>   int dp_catalog_ctrl_set_pattern_state_bit(struct dp_catalog *dp_catalog, u32 pattern);
>   u32 dp_catalog_hw_revision(const struct dp_catalog *dp_catalog);
>   void dp_catalog_ctrl_reset(struct dp_catalog *dp_catalog);
> diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> index 77a8d9366ed7b..209cf2a35642f 100644
> --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
> +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> @@ -128,6 +128,9 @@ static void dp_ctrl_config_ctrl(struct dp_ctrl_private *ctrl)
>   	/* Default-> LSCLK DIV: 1/4 LCLK  */
>   	config |= (2 << DP_CONFIGURATION_CTRL_LSCLK_DIV_SHIFT);
>   
> +	if (ctrl->panel->dp_mode.out_fmt_is_yuv_420)
> +		config |= DP_CONFIGURATION_CTRL_RGB_YUV; /* YUV420 */
> +

This definitely is not related to clock rate calculations.

>   	/* Scrambler reset enable */
>   	if (drm_dp_alternate_scrambler_reset_cap(dpcd))
>   		config |= DP_CONFIGURATION_CTRL_ASSR;
> @@ -957,7 +960,7 @@ static void dp_ctrl_calc_tu_parameters(struct dp_ctrl_private *ctrl,
>   	in.hporch = drm_mode->htotal - drm_mode->hdisplay;
>   	in.nlanes = ctrl->link->link_params.num_lanes;
>   	in.bpp = ctrl->panel->dp_mode.bpp;
> -	in.pixel_enc = 444;
> +	in.pixel_enc = ctrl->panel->dp_mode.out_fmt_is_yuv_420 ? 420 : 444;
>   	in.dsc_en = 0;
>   	in.async_en = 0;
>   	in.fec_en = 0;
> @@ -1763,6 +1766,8 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
>   		ctrl->link->link_params.rate = rate;
>   		ctrl->link->link_params.num_lanes =
>   			ctrl->panel->link_info.num_lanes;
> +		if (ctrl->panel->dp_mode.out_fmt_is_yuv_420)
> +			pixel_rate >>= 1;
>   	}
>   
>   	drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, pixel_rate=%lu\n",
> @@ -1878,7 +1883,7 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, bool force_link_train)
>   
>   	pixel_rate = pixel_rate_orig = ctrl->panel->dp_mode.drm_mode.clock;
>   
> -	if (dp_ctrl->wide_bus_en)
> +	if (dp_ctrl->wide_bus_en || ctrl->panel->dp_mode.out_fmt_is_yuv_420)
>   		pixel_rate >>= 1;
>   
>   	drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, pixel_rate=%lu\n",
> @@ -1917,7 +1922,8 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, bool force_link_train)
>   
>   	dp_catalog_ctrl_config_msa(ctrl->catalog,
>   		ctrl->link->link_params.rate,
> -		pixel_rate_orig, dp_ctrl_use_fixed_nvid(ctrl));
> +		pixel_rate_orig, dp_ctrl_use_fixed_nvid(ctrl),
> +		ctrl->panel->dp_mode.out_fmt_is_yuv_420);
>   
>   	dp_ctrl_setup_tr_unit(ctrl);
>   
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index f6b3b6ca242f8..6d764f5b08727 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -916,9 +916,10 @@ enum drm_mode_status dp_bridge_mode_valid(struct drm_bridge *bridge,
>   	const u32 num_components = 3, default_bpp = 24;
>   	struct dp_display_private *dp_display;
>   	struct dp_link_info *link_info;
> -	u32 mode_rate_khz = 0, supported_rate_khz = 0, mode_bpp = 0;
>   	struct msm_dp *dp;
>   	int mode_pclk_khz = mode->clock;
> +	int rate_ratio = RGB_24BPP_TMDS_CHAR_RATE_RATIO;
> +	u32 mode_rate_khz = 0, supported_rate_khz = 0, mode_bpp = 0;
>   
>   	dp = to_dp_bridge(bridge)->dp_display;
>   
> @@ -933,6 +934,11 @@ enum drm_mode_status dp_bridge_mode_valid(struct drm_bridge *bridge,
>   	dp_display = container_of(dp, struct dp_display_private, dp_display);
>   	link_info = &dp_display->panel->link_info;
>   
> +	if (drm_mode_is_420_only(&dp->connector->display_info, mode))
> +		rate_ratio = YUV420_24BPP_TMDS_CHAR_RATE_RATIO;
> +
> +	mode_pclk_khz /= rate_ratio;

I think it will be more obvious and simple to write:

if (drm_mode_is_420...)
     mode_pclk_khz /= 2;


> +
>   	mode_bpp = dp->connector->display_info.bpc * num_components;
>   	if (!mode_bpp)
>   		mode_bpp = default_bpp;
> diff --git a/drivers/gpu/drm/msm/msm_kms.h b/drivers/gpu/drm/msm/msm_kms.h
> index 44aa435d68ce2..66e8151951807 100644
> --- a/drivers/gpu/drm/msm/msm_kms.h
> +++ b/drivers/gpu/drm/msm/msm_kms.h
> @@ -15,6 +15,9 @@
>   
>   #define MAX_PLANE	4
>   
> +#define RGB_24BPP_TMDS_CHAR_RATE_RATIO		1
> +#define YUV420_24BPP_TMDS_CHAR_RATE_RATIO	2
> +
>   /* As there are different display controller blocks depending on the
>    * snapdragon version, the kms support is split out and the appropriate
>    * implementation is loaded at runtime.  The kms module is responsible
Paloma Arellano Jan. 28, 2024, 5:18 a.m. UTC | #2
On 1/25/2024 1:29 PM, Dmitry Baryshkov wrote:
> On 25/01/2024 21:38, Paloma Arellano wrote:
>> Change all relevant DP controller related programming for YUV420 cases.
>> Namely, change the pixel clock math to consider YUV420, program the
>> configuration control to indicate YUV420, as well as modify the MVID
>> programming to consider YUV420.
>
> Too many items for a single commit.
Ack. In the next series, I'll keep the clock math and MVID related code 
in one patch. And configuration control code in another.
>
>>
>> Signed-off-by: Paloma Arellano <quic_parellan@quicinc.com>
>> ---
>>   drivers/gpu/drm/msm/dp/dp_catalog.c |  5 ++++-
>>   drivers/gpu/drm/msm/dp/dp_catalog.h |  2 +-
>>   drivers/gpu/drm/msm/dp/dp_ctrl.c    | 12 +++++++++---
>>   drivers/gpu/drm/msm/dp/dp_display.c |  8 +++++++-
>>   drivers/gpu/drm/msm/msm_kms.h       |  3 +++
>>   5 files changed, 24 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.c 
>> b/drivers/gpu/drm/msm/dp/dp_catalog.c
>> index 5142aeb705a44..5d84c089e520a 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_catalog.c
>> +++ b/drivers/gpu/drm/msm/dp/dp_catalog.c
>> @@ -442,7 +442,7 @@ void dp_catalog_ctrl_config_misc(struct 
>> dp_catalog *dp_catalog,
>>     void dp_catalog_ctrl_config_msa(struct dp_catalog *dp_catalog,
>>                       u32 rate, u32 stream_rate_khz,
>> -                    bool fixed_nvid)
>> +                    bool fixed_nvid, bool is_ycbcr_420)
>>   {
>>       u32 pixel_m, pixel_n;
>>       u32 mvid, nvid, pixel_div = 0, dispcc_input_rate;
>> @@ -485,6 +485,9 @@ void dp_catalog_ctrl_config_msa(struct dp_catalog 
>> *dp_catalog,
>>           nvid = temp;
>>       }
>>   +    if (is_ycbcr_420)
>> +        mvid /= 2;
>> +
>>       if (link_rate_hbr2 == rate)
>>           nvid *= 2;
>>   diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.h 
>> b/drivers/gpu/drm/msm/dp/dp_catalog.h
>> index 38786e855b51a..6cb5e2a243de2 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_catalog.h
>> +++ b/drivers/gpu/drm/msm/dp/dp_catalog.h
>> @@ -96,7 +96,7 @@ void dp_catalog_ctrl_mainlink_ctrl(struct 
>> dp_catalog *dp_catalog, bool enable);
>>   void dp_catalog_ctrl_psr_mainlink_enable(struct dp_catalog 
>> *dp_catalog, bool enable);
>>   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);
>> +                u32 stream_rate_khz, bool fixed_nvid, bool 
>> is_ycbcr_420);
>>   int dp_catalog_ctrl_set_pattern_state_bit(struct dp_catalog 
>> *dp_catalog, u32 pattern);
>>   u32 dp_catalog_hw_revision(const struct dp_catalog *dp_catalog);
>>   void dp_catalog_ctrl_reset(struct dp_catalog *dp_catalog);
>> diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c 
>> b/drivers/gpu/drm/msm/dp/dp_ctrl.c
>> index 77a8d9366ed7b..209cf2a35642f 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
>> +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
>> @@ -128,6 +128,9 @@ static void dp_ctrl_config_ctrl(struct 
>> dp_ctrl_private *ctrl)
>>       /* Default-> LSCLK DIV: 1/4 LCLK  */
>>       config |= (2 << DP_CONFIGURATION_CTRL_LSCLK_DIV_SHIFT);
>>   +    if (ctrl->panel->dp_mode.out_fmt_is_yuv_420)
>> +        config |= DP_CONFIGURATION_CTRL_RGB_YUV; /* YUV420 */
>> +
>
> This definitely is not related to clock rate calculations.
This is related to the configuration control register.
>
>>       /* Scrambler reset enable */
>>       if (drm_dp_alternate_scrambler_reset_cap(dpcd))
>>           config |= DP_CONFIGURATION_CTRL_ASSR;
>> @@ -957,7 +960,7 @@ static void dp_ctrl_calc_tu_parameters(struct 
>> dp_ctrl_private *ctrl,
>>       in.hporch = drm_mode->htotal - drm_mode->hdisplay;
>>       in.nlanes = ctrl->link->link_params.num_lanes;
>>       in.bpp = ctrl->panel->dp_mode.bpp;
>> -    in.pixel_enc = 444;
>> +    in.pixel_enc = ctrl->panel->dp_mode.out_fmt_is_yuv_420 ? 420 : 444;
>>       in.dsc_en = 0;
>>       in.async_en = 0;
>>       in.fec_en = 0;
>> @@ -1763,6 +1766,8 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
>>           ctrl->link->link_params.rate = rate;
>>           ctrl->link->link_params.num_lanes =
>>               ctrl->panel->link_info.num_lanes;
>> +        if (ctrl->panel->dp_mode.out_fmt_is_yuv_420)
>> +            pixel_rate >>= 1;
>>       }
>>         drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, 
>> pixel_rate=%lu\n",
>> @@ -1878,7 +1883,7 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, 
>> bool force_link_train)
>>         pixel_rate = pixel_rate_orig = 
>> ctrl->panel->dp_mode.drm_mode.clock;
>>   -    if (dp_ctrl->wide_bus_en)
>> +    if (dp_ctrl->wide_bus_en || 
>> ctrl->panel->dp_mode.out_fmt_is_yuv_420)
>>           pixel_rate >>= 1;
>>         drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, 
>> pixel_rate=%lu\n",
>> @@ -1917,7 +1922,8 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, 
>> bool force_link_train)
>>         dp_catalog_ctrl_config_msa(ctrl->catalog,
>>           ctrl->link->link_params.rate,
>> -        pixel_rate_orig, dp_ctrl_use_fixed_nvid(ctrl));
>> +        pixel_rate_orig, dp_ctrl_use_fixed_nvid(ctrl),
>> +        ctrl->panel->dp_mode.out_fmt_is_yuv_420);
>>         dp_ctrl_setup_tr_unit(ctrl);
>>   diff --git a/drivers/gpu/drm/msm/dp/dp_display.c 
>> b/drivers/gpu/drm/msm/dp/dp_display.c
>> index f6b3b6ca242f8..6d764f5b08727 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_display.c
>> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
>> @@ -916,9 +916,10 @@ enum drm_mode_status dp_bridge_mode_valid(struct 
>> drm_bridge *bridge,
>>       const u32 num_components = 3, default_bpp = 24;
>>       struct dp_display_private *dp_display;
>>       struct dp_link_info *link_info;
>> -    u32 mode_rate_khz = 0, supported_rate_khz = 0, mode_bpp = 0;
>>       struct msm_dp *dp;
>>       int mode_pclk_khz = mode->clock;
>> +    int rate_ratio = RGB_24BPP_TMDS_CHAR_RATE_RATIO;
>> +    u32 mode_rate_khz = 0, supported_rate_khz = 0, mode_bpp = 0;
>>         dp = to_dp_bridge(bridge)->dp_display;
>>   @@ -933,6 +934,11 @@ enum drm_mode_status 
>> dp_bridge_mode_valid(struct drm_bridge *bridge,
>>       dp_display = container_of(dp, struct dp_display_private, 
>> dp_display);
>>       link_info = &dp_display->panel->link_info;
>>   +    if (drm_mode_is_420_only(&dp->connector->display_info, mode))
>> +        rate_ratio = YUV420_24BPP_TMDS_CHAR_RATE_RATIO;
>> +
>> +    mode_pclk_khz /= rate_ratio;
>
> I think it will be more obvious and simple to write:
>
> if (drm_mode_is_420...)
>     mode_pclk_khz /= 2;
Ack
>
>
>> +
>>       mode_bpp = dp->connector->display_info.bpc * num_components;
>>       if (!mode_bpp)
>>           mode_bpp = default_bpp;
>> diff --git a/drivers/gpu/drm/msm/msm_kms.h 
>> b/drivers/gpu/drm/msm/msm_kms.h
>> index 44aa435d68ce2..66e8151951807 100644
>> --- a/drivers/gpu/drm/msm/msm_kms.h
>> +++ b/drivers/gpu/drm/msm/msm_kms.h
>> @@ -15,6 +15,9 @@
>>     #define MAX_PLANE    4
>>   +#define RGB_24BPP_TMDS_CHAR_RATE_RATIO        1
>> +#define YUV420_24BPP_TMDS_CHAR_RATE_RATIO    2
>> +
>>   /* As there are different display controller blocks depending on the
>>    * snapdragon version, the kms support is split out and the 
>> appropriate
>>    * implementation is loaded at runtime.  The kms module is responsible
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.c b/drivers/gpu/drm/msm/dp/dp_catalog.c
index 5142aeb705a44..5d84c089e520a 100644
--- a/drivers/gpu/drm/msm/dp/dp_catalog.c
+++ b/drivers/gpu/drm/msm/dp/dp_catalog.c
@@ -442,7 +442,7 @@  void dp_catalog_ctrl_config_misc(struct dp_catalog *dp_catalog,
 
 void dp_catalog_ctrl_config_msa(struct dp_catalog *dp_catalog,
 					u32 rate, u32 stream_rate_khz,
-					bool fixed_nvid)
+					bool fixed_nvid, bool is_ycbcr_420)
 {
 	u32 pixel_m, pixel_n;
 	u32 mvid, nvid, pixel_div = 0, dispcc_input_rate;
@@ -485,6 +485,9 @@  void dp_catalog_ctrl_config_msa(struct dp_catalog *dp_catalog,
 		nvid = temp;
 	}
 
+	if (is_ycbcr_420)
+		mvid /= 2;
+
 	if (link_rate_hbr2 == rate)
 		nvid *= 2;
 
diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.h b/drivers/gpu/drm/msm/dp/dp_catalog.h
index 38786e855b51a..6cb5e2a243de2 100644
--- a/drivers/gpu/drm/msm/dp/dp_catalog.h
+++ b/drivers/gpu/drm/msm/dp/dp_catalog.h
@@ -96,7 +96,7 @@  void dp_catalog_ctrl_mainlink_ctrl(struct dp_catalog *dp_catalog, bool enable);
 void dp_catalog_ctrl_psr_mainlink_enable(struct dp_catalog *dp_catalog, bool enable);
 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);
+				u32 stream_rate_khz, bool fixed_nvid, bool is_ycbcr_420);
 int dp_catalog_ctrl_set_pattern_state_bit(struct dp_catalog *dp_catalog, u32 pattern);
 u32 dp_catalog_hw_revision(const struct dp_catalog *dp_catalog);
 void dp_catalog_ctrl_reset(struct dp_catalog *dp_catalog);
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index 77a8d9366ed7b..209cf2a35642f 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -128,6 +128,9 @@  static void dp_ctrl_config_ctrl(struct dp_ctrl_private *ctrl)
 	/* Default-> LSCLK DIV: 1/4 LCLK  */
 	config |= (2 << DP_CONFIGURATION_CTRL_LSCLK_DIV_SHIFT);
 
+	if (ctrl->panel->dp_mode.out_fmt_is_yuv_420)
+		config |= DP_CONFIGURATION_CTRL_RGB_YUV; /* YUV420 */
+
 	/* Scrambler reset enable */
 	if (drm_dp_alternate_scrambler_reset_cap(dpcd))
 		config |= DP_CONFIGURATION_CTRL_ASSR;
@@ -957,7 +960,7 @@  static void dp_ctrl_calc_tu_parameters(struct dp_ctrl_private *ctrl,
 	in.hporch = drm_mode->htotal - drm_mode->hdisplay;
 	in.nlanes = ctrl->link->link_params.num_lanes;
 	in.bpp = ctrl->panel->dp_mode.bpp;
-	in.pixel_enc = 444;
+	in.pixel_enc = ctrl->panel->dp_mode.out_fmt_is_yuv_420 ? 420 : 444;
 	in.dsc_en = 0;
 	in.async_en = 0;
 	in.fec_en = 0;
@@ -1763,6 +1766,8 @@  int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
 		ctrl->link->link_params.rate = rate;
 		ctrl->link->link_params.num_lanes =
 			ctrl->panel->link_info.num_lanes;
+		if (ctrl->panel->dp_mode.out_fmt_is_yuv_420)
+			pixel_rate >>= 1;
 	}
 
 	drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, pixel_rate=%lu\n",
@@ -1878,7 +1883,7 @@  int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, bool force_link_train)
 
 	pixel_rate = pixel_rate_orig = ctrl->panel->dp_mode.drm_mode.clock;
 
-	if (dp_ctrl->wide_bus_en)
+	if (dp_ctrl->wide_bus_en || ctrl->panel->dp_mode.out_fmt_is_yuv_420)
 		pixel_rate >>= 1;
 
 	drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, pixel_rate=%lu\n",
@@ -1917,7 +1922,8 @@  int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, bool force_link_train)
 
 	dp_catalog_ctrl_config_msa(ctrl->catalog,
 		ctrl->link->link_params.rate,
-		pixel_rate_orig, dp_ctrl_use_fixed_nvid(ctrl));
+		pixel_rate_orig, dp_ctrl_use_fixed_nvid(ctrl),
+		ctrl->panel->dp_mode.out_fmt_is_yuv_420);
 
 	dp_ctrl_setup_tr_unit(ctrl);
 
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index f6b3b6ca242f8..6d764f5b08727 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -916,9 +916,10 @@  enum drm_mode_status dp_bridge_mode_valid(struct drm_bridge *bridge,
 	const u32 num_components = 3, default_bpp = 24;
 	struct dp_display_private *dp_display;
 	struct dp_link_info *link_info;
-	u32 mode_rate_khz = 0, supported_rate_khz = 0, mode_bpp = 0;
 	struct msm_dp *dp;
 	int mode_pclk_khz = mode->clock;
+	int rate_ratio = RGB_24BPP_TMDS_CHAR_RATE_RATIO;
+	u32 mode_rate_khz = 0, supported_rate_khz = 0, mode_bpp = 0;
 
 	dp = to_dp_bridge(bridge)->dp_display;
 
@@ -933,6 +934,11 @@  enum drm_mode_status dp_bridge_mode_valid(struct drm_bridge *bridge,
 	dp_display = container_of(dp, struct dp_display_private, dp_display);
 	link_info = &dp_display->panel->link_info;
 
+	if (drm_mode_is_420_only(&dp->connector->display_info, mode))
+		rate_ratio = YUV420_24BPP_TMDS_CHAR_RATE_RATIO;
+
+	mode_pclk_khz /= rate_ratio;
+
 	mode_bpp = dp->connector->display_info.bpc * num_components;
 	if (!mode_bpp)
 		mode_bpp = default_bpp;
diff --git a/drivers/gpu/drm/msm/msm_kms.h b/drivers/gpu/drm/msm/msm_kms.h
index 44aa435d68ce2..66e8151951807 100644
--- a/drivers/gpu/drm/msm/msm_kms.h
+++ b/drivers/gpu/drm/msm/msm_kms.h
@@ -15,6 +15,9 @@ 
 
 #define MAX_PLANE	4
 
+#define RGB_24BPP_TMDS_CHAR_RATE_RATIO		1
+#define YUV420_24BPP_TMDS_CHAR_RATE_RATIO	2
+
 /* As there are different display controller blocks depending on the
  * snapdragon version, the kms support is split out and the appropriate
  * implementation is loaded at runtime.  The kms module is responsible