[PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

[PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

[Rajib Mahapatra]

[Why]
During resume path, dpcd_set_source_specific_data is taking
extra time when core_link_write_dpcd fails on DP_SOURCE_OUI+0x03
and DP_SOURCE_MINIMUM_HBLANK_SUPPORTED. Here,aux->transfer fails
with multiple retries and consume sigficantamount time during
S0i3 resume.

[How]
Not to call dpcd_set_source_specific_data during resume path
when there is no oled panel connected and achieve faster resume
during S0i3.

Signed-off-by: Rajib Mahapatra <rajib.mahapatra@amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index c0bdc23702c8..04086c199dbb 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -892,7 +892,8 @@ static bool dc_link_detect_helper(struct dc_link *link,
 		(!link->dc->config.allow_edp_hotplug_detection)) &&
 		link->local_sink) {
 		// need to re-write OUI and brightness in resume case
-		if (link->connector_signal == SIGNAL_TYPE_EDP) {
+		if (link->connector_signal == SIGNAL_TYPE_EDP &&
+			(link->dpcd_sink_ext_caps.bits.oled == 1)) {
 			dpcd_set_source_specific_data(link);
 			msleep(post_oui_delay);
 			dc_link_set_default_brightness_aux(link);
-- 
2.25.1

Re: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

[Deucher, Alexander]

[-- Attachment #1: Type: text/plain, Size: 2082 bytes --]

[Public]

Seems reasonable.

Acked-by: Alex Deucher <alexander.deucher@amd.com>
________________________________
From: Mahapatra, Rajib <Rajib.Mahapatra@amd.com>
Sent: Monday, January 10, 2022 4:06 AM
To: Wu, Hersen <hersenxs.wu@amd.com>; Wentland, Harry <Harry.Wentland@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>
Cc: amd-gfx@lists.freedesktop.org <amd-gfx@lists.freedesktop.org>; S, Shirish <Shirish.S@amd.com>; Mahapatra, Rajib <Rajib.Mahapatra@amd.com>
Subject: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

[Why]
During resume path, dpcd_set_source_specific_data is taking
extra time when core_link_write_dpcd fails on DP_SOURCE_OUI+0x03
and DP_SOURCE_MINIMUM_HBLANK_SUPPORTED. Here,aux->transfer fails
with multiple retries and consume sigficantamount time during
S0i3 resume.

[How]
Not to call dpcd_set_source_specific_data during resume path
when there is no oled panel connected and achieve faster resume
during S0i3.

Signed-off-by: Rajib Mahapatra <rajib.mahapatra@amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index c0bdc23702c8..04086c199dbb 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -892,7 +892,8 @@ static bool dc_link_detect_helper(struct dc_link *link,
                 (!link->dc->config.allow_edp_hotplug_detection)) &&
                 link->local_sink) {
                 // need to re-write OUI and brightness in resume case
-               if (link->connector_signal == SIGNAL_TYPE_EDP) {
+               if (link->connector_signal == SIGNAL_TYPE_EDP &&
+                       (link->dpcd_sink_ext_caps.bits.oled == 1)) {
                         dpcd_set_source_specific_data(link);
                         msleep(post_oui_delay);
                         dc_link_set_default_brightness_aux(link);
--
2.25.1


[-- Attachment #2: Type: text/html, Size: 4224 bytes --]

Re: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

[Harry Wentland]

On 2022-01-10 04:06, Rajib Mahapatra wrote:
> [Why]
> During resume path, dpcd_set_source_specific_data is taking
> extra time when core_link_write_dpcd fails on DP_SOURCE_OUI+0x03
> and DP_SOURCE_MINIMUM_HBLANK_SUPPORTED. Here,aux->transfer fails
> with multiple retries and consume sigficantamount time during
> S0i3 resume.
> 
> [How]
> Not to call dpcd_set_source_specific_data during resume path
> when there is no oled panel connected and achieve faster resume
> during S0i3.
> 
> Signed-off-by: Rajib Mahapatra <rajib.mahapatra@amd.com>
> ---
>  drivers/gpu/drm/amd/display/dc/core/dc_link.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> index c0bdc23702c8..04086c199dbb 100644
> --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> @@ -892,7 +892,8 @@ static bool dc_link_detect_helper(struct dc_link *link,
>  		(!link->dc->config.allow_edp_hotplug_detection)) &&
>  		link->local_sink) {
>  		// need to re-write OUI and brightness in resume case
> -		if (link->connector_signal == SIGNAL_TYPE_EDP) {
> +		if (link->connector_signal == SIGNAL_TYPE_EDP &&
> +			(link->dpcd_sink_ext_caps.bits.oled == 1)) {

Is the source specific data only used by OLED panels?

Do we know that this won't lead to regressions with any features on non-OLED panels?

Harry

>  			dpcd_set_source_specific_data(link);
>  			msleep(post_oui_delay);
>  			dc_link_set_default_brightness_aux(link);

RE: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

[Mahapatra, Rajib]

dpcd_set_source_specific_data is not specific to OLED panel.  It is called from boot-up path also.
Hersen Wu introduced it in resume-path while enabling OLED panel for Linux in below commit.

So here, I guard it by calling source specific data only for OLED panel, and I can get advantage of around 100ms for non-oled panel during resume. Hersen night have answer about the issue related to regression for other panels, waiting for his reply about this change.

commit 96577cf82a1331732a71199522398120c649f1cf
Author: Hersen Wu <hersenxs.wu@amd.com>
Date:   Tue Jan 14 15:39:07 2020 -0500

    drm/amd/display: linux enable oled panel support dc part



-----Original Message-----
From: Wentland, Harry <Harry.Wentland@amd.com> 
Sent: Monday, January 10, 2022 10:03 PM
To: Mahapatra, Rajib <Rajib.Mahapatra@amd.com>; Wu, Hersen <hersenxs.wu@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>
Cc: amd-gfx@lists.freedesktop.org; S, Shirish <Shirish.S@amd.com>
Subject: Re: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

On 2022-01-10 04:06, Rajib Mahapatra wrote:
> [Why]
> During resume path, dpcd_set_source_specific_data is taking extra time 
> when core_link_write_dpcd fails on DP_SOURCE_OUI+0x03 and 
> DP_SOURCE_MINIMUM_HBLANK_SUPPORTED. Here,aux->transfer fails with 
> multiple retries and consume sigficantamount time during
> S0i3 resume.
> 
> [How]
> Not to call dpcd_set_source_specific_data during resume path when 
> there is no oled panel connected and achieve faster resume during 
> S0i3.
> 
> Signed-off-by: Rajib Mahapatra <rajib.mahapatra@amd.com>
> ---
>  drivers/gpu/drm/amd/display/dc/core/dc_link.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c 
> b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> index c0bdc23702c8..04086c199dbb 100644
> --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> @@ -892,7 +892,8 @@ static bool dc_link_detect_helper(struct dc_link *link,
>  		(!link->dc->config.allow_edp_hotplug_detection)) &&
>  		link->local_sink) {
>  		// need to re-write OUI and brightness in resume case
> -		if (link->connector_signal == SIGNAL_TYPE_EDP) {
> +		if (link->connector_signal == SIGNAL_TYPE_EDP &&
> +			(link->dpcd_sink_ext_caps.bits.oled == 1)) {

Is the source specific data only used by OLED panels?

Do we know that this won't lead to regressions with any features on non-OLED panels?

Harry

>  			dpcd_set_source_specific_data(link);
>  			msleep(post_oui_delay);
>  			dc_link_set_default_brightness_aux(link);

Re: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

[Harry Wentland]

On 2022-01-11 02:52, Mahapatra, Rajib wrote:
> dpcd_set_source_specific_data is not specific to OLED panel.  It is called from boot-up path also.
> Hersen Wu introduced it in resume-path while enabling OLED panel for Linux in below commit.
> 

If we set it in the boot-up path we'll probably want to set it on resume as well. Though I'll let Hersen comment since he knows this part much better than me.

Harry

> So here, I guard it by calling source specific data only for OLED panel, and I can get advantage of around 100ms for non-oled panel during resume. Hersen night have answer about the issue related to regression for other panels, waiting for his reply about this change.
> 
> commit 96577cf82a1331732a71199522398120c649f1cf
> Author: Hersen Wu <hersenxs.wu@amd.com>
> Date:   Tue Jan 14 15:39:07 2020 -0500
> 
>     drm/amd/display: linux enable oled panel support dc part
> 
> 
> 
> -----Original Message-----
> From: Wentland, Harry <Harry.Wentland@amd.com> 
> Sent: Monday, January 10, 2022 10:03 PM
> To: Mahapatra, Rajib <Rajib.Mahapatra@amd.com>; Wu, Hersen <hersenxs.wu@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>
> Cc: amd-gfx@lists.freedesktop.org; S, Shirish <Shirish.S@amd.com>
> Subject: Re: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.
> 
> On 2022-01-10 04:06, Rajib Mahapatra wrote:
>> [Why]
>> During resume path, dpcd_set_source_specific_data is taking extra time 
>> when core_link_write_dpcd fails on DP_SOURCE_OUI+0x03 and 
>> DP_SOURCE_MINIMUM_HBLANK_SUPPORTED. Here,aux->transfer fails with 
>> multiple retries and consume sigficantamount time during
>> S0i3 resume.
>>
>> [How]
>> Not to call dpcd_set_source_specific_data during resume path when 
>> there is no oled panel connected and achieve faster resume during 
>> S0i3.
>>
>> Signed-off-by: Rajib Mahapatra <rajib.mahapatra@amd.com>
>> ---
>>  drivers/gpu/drm/amd/display/dc/core/dc_link.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c 
>> b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> index c0bdc23702c8..04086c199dbb 100644
>> --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> @@ -892,7 +892,8 @@ static bool dc_link_detect_helper(struct dc_link *link,
>>  		(!link->dc->config.allow_edp_hotplug_detection)) &&
>>  		link->local_sink) {
>>  		// need to re-write OUI and brightness in resume case
>> -		if (link->connector_signal == SIGNAL_TYPE_EDP) {
>> +		if (link->connector_signal == SIGNAL_TYPE_EDP &&
>> +			(link->dpcd_sink_ext_caps.bits.oled == 1)) {
> 
> Is the source specific data only used by OLED panels?
> 
> Do we know that this won't lead to regressions with any features on non-OLED panels?
> 
> Harry
> 
>>  			dpcd_set_source_specific_data(link);
>>  			msleep(post_oui_delay);
>>  			dc_link_set_default_brightness_aux(link);
> 

RE: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

[Mahapatra, Rajib]

Hi Hersen,
I am waiting for your comments here.
I think we can take this change for resume path at this moment.
For bootup, we can have separate patch for resume optimization. 

Thanks
-Rajib

-----Original Message-----
From: Wentland, Harry <Harry.Wentland@amd.com> 
Sent: Tuesday, January 11, 2022 9:47 PM
To: Mahapatra, Rajib <Rajib.Mahapatra@amd.com>; Wu, Hersen <hersenxs.wu@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>
Cc: amd-gfx@lists.freedesktop.org; S, Shirish <Shirish.S@amd.com>
Subject: Re: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.



On 2022-01-11 02:52, Mahapatra, Rajib wrote:
> dpcd_set_source_specific_data is not specific to OLED panel.  It is called from boot-up path also.
> Hersen Wu introduced it in resume-path while enabling OLED panel for Linux in below commit.
> 

If we set it in the boot-up path we'll probably want to set it on resume as well. Though I'll let Hersen comment since he knows this part much better than me.

Harry

> So here, I guard it by calling source specific data only for OLED panel, and I can get advantage of around 100ms for non-oled panel during resume. Hersen night have answer about the issue related to regression for other panels, waiting for his reply about this change.
> 
> commit 96577cf82a1331732a71199522398120c649f1cf
> Author: Hersen Wu <hersenxs.wu@amd.com>
> Date:   Tue Jan 14 15:39:07 2020 -0500
> 
>     drm/amd/display: linux enable oled panel support dc part
> 
> 
> 
> -----Original Message-----
> From: Wentland, Harry <Harry.Wentland@amd.com>
> Sent: Monday, January 10, 2022 10:03 PM
> To: Mahapatra, Rajib <Rajib.Mahapatra@amd.com>; Wu, Hersen 
> <hersenxs.wu@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>
> Cc: amd-gfx@lists.freedesktop.org; S, Shirish <Shirish.S@amd.com>
> Subject: Re: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.
> 
> On 2022-01-10 04:06, Rajib Mahapatra wrote:
>> [Why]
>> During resume path, dpcd_set_source_specific_data is taking extra 
>> time when core_link_write_dpcd fails on DP_SOURCE_OUI+0x03 and 
>> DP_SOURCE_MINIMUM_HBLANK_SUPPORTED. Here,aux->transfer fails with 
>> multiple retries and consume sigficantamount time during
>> S0i3 resume.
>>
>> [How]
>> Not to call dpcd_set_source_specific_data during resume path when 
>> there is no oled panel connected and achieve faster resume during 
>> S0i3.
>>
>> Signed-off-by: Rajib Mahapatra <rajib.mahapatra@amd.com>
>> ---
>>  drivers/gpu/drm/amd/display/dc/core/dc_link.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> index c0bdc23702c8..04086c199dbb 100644
>> --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> @@ -892,7 +892,8 @@ static bool dc_link_detect_helper(struct dc_link *link,
>>  		(!link->dc->config.allow_edp_hotplug_detection)) &&
>>  		link->local_sink) {
>>  		// need to re-write OUI and brightness in resume case
>> -		if (link->connector_signal == SIGNAL_TYPE_EDP) {
>> +		if (link->connector_signal == SIGNAL_TYPE_EDP &&
>> +			(link->dpcd_sink_ext_caps.bits.oled == 1)) {
> 
> Is the source specific data only used by OLED panels?
> 
> Do we know that this won't lead to regressions with any features on non-OLED panels?
> 
> Harry
> 
>>  			dpcd_set_source_specific_data(link);
>>  			msleep(post_oui_delay);
>>  			dc_link_set_default_brightness_aux(link);
> 

RE: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

[Wu, Hersen]

[AMD Official Use Only]

Hi Rajib,

For resume from s3 or si03, the change should work.

Reviewed-by: Hersen Wu <hersenxs.wu@amd.com>

For boot up, at the location of your change, link->dpcd_sink_ext_caps.bits.oled = 0.
OLED caps is read by dpcd_read_sink_ext_caps which is called within  detect_edp_sink_caps.

For boot up, we need another change.

Thanks!
Hersen



-----Original Message-----
From: Mahapatra, Rajib <Rajib.Mahapatra@amd.com> 
Sent: Thursday, January 20, 2022 2:33 PM
To: Wentland, Harry <Harry.Wentland@amd.com>; Wu, Hersen <hersenxs.wu@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>
Cc: amd-gfx@lists.freedesktop.org; S, Shirish <Shirish.S@amd.com>
Subject: RE: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

Hi Hersen,
I am waiting for your comments here.
I think we can take this change for resume path at this moment.
For bootup, we can have separate patch for resume optimization. 

Thanks
-Rajib

-----Original Message-----
From: Wentland, Harry <Harry.Wentland@amd.com> 
Sent: Tuesday, January 11, 2022 9:47 PM
To: Mahapatra, Rajib <Rajib.Mahapatra@amd.com>; Wu, Hersen <hersenxs.wu@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>
Cc: amd-gfx@lists.freedesktop.org; S, Shirish <Shirish.S@amd.com>
Subject: Re: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.



On 2022-01-11 02:52, Mahapatra, Rajib wrote:
> dpcd_set_source_specific_data is not specific to OLED panel.  It is called from boot-up path also.
> Hersen Wu introduced it in resume-path while enabling OLED panel for Linux in below commit.
> 

If we set it in the boot-up path we'll probably want to set it on resume as well. Though I'll let Hersen comment since he knows this part much better than me.

Harry

> So here, I guard it by calling source specific data only for OLED panel, and I can get advantage of around 100ms for non-oled panel during resume. Hersen night have answer about the issue related to regression for other panels, waiting for his reply about this change.
> 
> commit 96577cf82a1331732a71199522398120c649f1cf
> Author: Hersen Wu <hersenxs.wu@amd.com>
> Date:   Tue Jan 14 15:39:07 2020 -0500
> 
>     drm/amd/display: linux enable oled panel support dc part
> 
> 
> 
> -----Original Message-----
> From: Wentland, Harry <Harry.Wentland@amd.com>
> Sent: Monday, January 10, 2022 10:03 PM
> To: Mahapatra, Rajib <Rajib.Mahapatra@amd.com>; Wu, Hersen 
> <hersenxs.wu@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>
> Cc: amd-gfx@lists.freedesktop.org; S, Shirish <Shirish.S@amd.com>
> Subject: Re: [PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.
> 
> On 2022-01-10 04:06, Rajib Mahapatra wrote:
>> [Why]
>> During resume path, dpcd_set_source_specific_data is taking extra 
>> time when core_link_write_dpcd fails on DP_SOURCE_OUI+0x03 and 
>> DP_SOURCE_MINIMUM_HBLANK_SUPPORTED. Here,aux->transfer fails with 
>> multiple retries and consume sigficantamount time during
>> S0i3 resume.
>>
>> [How]
>> Not to call dpcd_set_source_specific_data during resume path when 
>> there is no oled panel connected and achieve faster resume during 
>> S0i3.
>>
>> Signed-off-by: Rajib Mahapatra <rajib.mahapatra@amd.com>
>> ---
>>  drivers/gpu/drm/amd/display/dc/core/dc_link.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> index c0bdc23702c8..04086c199dbb 100644
>> --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
>> @@ -892,7 +892,8 @@ static bool dc_link_detect_helper(struct dc_link *link,
>>  		(!link->dc->config.allow_edp_hotplug_detection)) &&
>>  		link->local_sink) {
>>  		// need to re-write OUI and brightness in resume case
>> -		if (link->connector_signal == SIGNAL_TYPE_EDP) {
>> +		if (link->connector_signal == SIGNAL_TYPE_EDP &&
>> +			(link->dpcd_sink_ext_caps.bits.oled == 1)) {
> 
> Is the source specific data only used by OLED panels?
> 
> Do we know that this won't lead to regressions with any features on non-OLED panels?
> 
> Harry
> 
>>  			dpcd_set_source_specific_data(link);
>>  			msleep(post_oui_delay);
>>  			dc_link_set_default_brightness_aux(link);
>