[PATCH] drm/amd/display: Reject cursor plane on DCE when scaled differently than primary

[PATCH] drm/amd/display: Reject cursor plane on DCE when scaled differently than primary

[Timur Kristóf]

Currently DCE doesn't support the overlay cursor, so the
dm_crtc_get_cursor_mode() function returns DM_CURSOR_NATIVE_MODE
unconditionally. The outcome is that it doesn't check for the
conditions that would necessitate the overlay cursor, meaning
that it doesn't reject cases where the native cursor mode isn't
supported on DCE.

Remove the early return from dm_crtc_get_cursor_mode() for
DCE and instead let it perform the necessary checks and
return DM_CURSOR_OVERLAY_MODE. Add a later check that rejects
when DM_CURSOR_OVERLAY_MODE would be used with DCE.

Fixes: 1b04dcca4fb1 ("drm/amd/display: Introduce overlay cursor mode")
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4600
Suggested-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 655c9fcb078a..3e1ba5521f2b 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -12262,10 +12262,9 @@ static int dm_crtc_get_cursor_mode(struct amdgpu_device *adev,
 
 	/* Overlay cursor not supported on HW before DCN
 	 * DCN401 does not have the cursor-on-scaled-plane or cursor-on-yuv-plane restrictions
-	 * as previous DCN generations, so enable native mode on DCN401 in addition to DCE
+	 * as previous DCN generations, so enable native mode on DCN401
 	 */
-	if (amdgpu_ip_version(adev, DCE_HWIP, 0) == 0 ||
-	    amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 0, 1)) {
+	if (amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 0, 1)) {
 		*cursor_mode = DM_CURSOR_NATIVE_MODE;
 		return 0;
 	}
@@ -12585,6 +12584,12 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 		 * need to be added for DC to not disable a plane by mistake
 		 */
 		if (dm_new_crtc_state->cursor_mode == DM_CURSOR_OVERLAY_MODE) {
+			if (amdgpu_ip_version(adev, DCE_HWIP, 0) == 0) {
+				drm_dbg(dev, "Overlay cursor not supported on DCE\n");
+				ret = -EINVAL;
+				goto fail;
+			}
+
 			ret = drm_atomic_add_affected_planes(state, crtc);
 			if (ret)
 				goto fail;
-- 
2.52.0

Re: [PATCH] drm/amd/display: Reject cursor plane on DCE when scaled differently than primary

[Rodrigo Siqueira]

On 01/18, Timur Kristóf wrote:
> Currently DCE doesn't support the overlay cursor, so the
> dm_crtc_get_cursor_mode() function returns DM_CURSOR_NATIVE_MODE
> unconditionally. The outcome is that it doesn't check for the
> conditions that would necessitate the overlay cursor, meaning
> that it doesn't reject cases where the native cursor mode isn't
> supported on DCE.
> 
> Remove the early return from dm_crtc_get_cursor_mode() for
> DCE and instead let it perform the necessary checks and
> return DM_CURSOR_OVERLAY_MODE. Add a later check that rejects
> when DM_CURSOR_OVERLAY_MODE would be used with DCE.
> 
> Fixes: 1b04dcca4fb1 ("drm/amd/display: Introduce overlay cursor mode")
> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4600
> Suggested-by: Leo Li <sunpeng.li@amd.com>
> Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 655c9fcb078a..3e1ba5521f2b 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -12262,10 +12262,9 @@ static int dm_crtc_get_cursor_mode(struct amdgpu_device *adev,
>  
>  	/* Overlay cursor not supported on HW before DCN
>  	 * DCN401 does not have the cursor-on-scaled-plane or cursor-on-yuv-plane restrictions
> -	 * as previous DCN generations, so enable native mode on DCN401 in addition to DCE
> +	 * as previous DCN generations, so enable native mode on DCN401
>  	 */
> -	if (amdgpu_ip_version(adev, DCE_HWIP, 0) == 0 ||
> -	    amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 0, 1)) {
> +	if (amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 0, 1)) {
>  		*cursor_mode = DM_CURSOR_NATIVE_MODE;
>  		return 0;
>  	}
> @@ -12585,6 +12584,12 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
>  		 * need to be added for DC to not disable a plane by mistake
>  		 */
>  		if (dm_new_crtc_state->cursor_mode == DM_CURSOR_OVERLAY_MODE) {
> +			if (amdgpu_ip_version(adev, DCE_HWIP, 0) == 0) {
> +				drm_dbg(dev, "Overlay cursor not supported on DCE\n");
> +				ret = -EINVAL;
> +				goto fail;
> +			}
> +
>  			ret = drm_atomic_add_affected_planes(state, crtc);
>  			if (ret)
>  				goto fail;
> -- 
> 2.52.0
>

Hi,

This change lgtm.

Alex, Dan,
Could you include this patch in the next week promotion? 

Reviewed-by: Rodrigo Siqueira <siqueira@igalia.com>

Thanks

-- 
Rodrigo Siqueira

RE: [PATCH] drm/amd/display: Reject cursor plane on DCE when scaled differently than primary

[Wheeler, Daniel]

[Public]

+@Chung, ChiaHsuan (Tom) as he's running promotion next week.

Thanks for the heads up Siqueira!

Thank you,

Dan Wheeler
Sr. Technologist | AMD
SW Display
------------------------------------------------------------------------------------------------------------------
1 Commerce Valley Dr E, Thornhill, ON L3T 7X6
amd.com


-----Original Message-----
From: Rodrigo Siqueira <siqueira@igalia.com>
Sent: Thursday, January 29, 2026 7:45 PM
To: Timur Kristóf <timur.kristof@gmail.com>; Hung, Alex <Alex.Hung@amd.com>; Wheeler, Daniel <Daniel.Wheeler@amd.com>
Cc: amd-gfx@lists.freedesktop.org; Deucher, Alexander <Alexander.Deucher@amd.com>; Limonciello, Mario <Mario.Limonciello@amd.com>; LIPSKI, IVAN <IVAN.LIPSKI@amd.com>; Wentland, Harry <Harry.Wentland@amd.com>; Li, Sun peng (Leo) <Sunpeng.Li@amd.com>
Subject: Re: [PATCH] drm/amd/display: Reject cursor plane on DCE when scaled differently than primary

On 01/18, Timur Kristóf wrote:
> Currently DCE doesn't support the overlay cursor, so the
> dm_crtc_get_cursor_mode() function returns DM_CURSOR_NATIVE_MODE
> unconditionally. The outcome is that it doesn't check for the
> conditions that would necessitate the overlay cursor, meaning that it
> doesn't reject cases where the native cursor mode isn't supported on
> DCE.
>
> Remove the early return from dm_crtc_get_cursor_mode() for DCE and
> instead let it perform the necessary checks and return
> DM_CURSOR_OVERLAY_MODE. Add a later check that rejects when
> DM_CURSOR_OVERLAY_MODE would be used with DCE.
>
> Fixes: 1b04dcca4fb1 ("drm/amd/display: Introduce overlay cursor mode")
> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4600
> Suggested-by: Leo Li <sunpeng.li@amd.com>
> Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 655c9fcb078a..3e1ba5521f2b 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -12262,10 +12262,9 @@ static int dm_crtc_get_cursor_mode(struct
> amdgpu_device *adev,
>
>       /* Overlay cursor not supported on HW before DCN
>        * DCN401 does not have the cursor-on-scaled-plane or cursor-on-yuv-plane restrictions
> -      * as previous DCN generations, so enable native mode on DCN401 in addition to DCE
> +      * as previous DCN generations, so enable native mode on DCN401
>        */
> -     if (amdgpu_ip_version(adev, DCE_HWIP, 0) == 0 ||
> -         amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 0, 1)) {
> +     if (amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 0, 1)) {
>               *cursor_mode = DM_CURSOR_NATIVE_MODE;
>               return 0;
>       }
> @@ -12585,6 +12584,12 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
>                * need to be added for DC to not disable a plane by mistake
>                */
>               if (dm_new_crtc_state->cursor_mode == DM_CURSOR_OVERLAY_MODE) {
> +                     if (amdgpu_ip_version(adev, DCE_HWIP, 0) == 0) {
> +                             drm_dbg(dev, "Overlay cursor not supported on DCE\n");
> +                             ret = -EINVAL;
> +                             goto fail;
> +                     }
> +
>                       ret = drm_atomic_add_affected_planes(state, crtc);
>                       if (ret)
>                               goto fail;
> --
> 2.52.0
>

Hi,

This change lgtm.

Alex, Dan,
Could you include this patch in the next week promotion?

Reviewed-by: Rodrigo Siqueira <siqueira@igalia.com>

Thanks

--
Rodrigo Siqueira

Re: [PATCH] drm/amd/display: Reject cursor plane on DCE when scaled differently than primary

[Alex Hung]

On 1/29/26 17:45, Rodrigo Siqueira wrote:
> On 01/18, Timur Kristóf wrote:
>> Currently DCE doesn't support the overlay cursor, so the
>> dm_crtc_get_cursor_mode() function returns DM_CURSOR_NATIVE_MODE
>> unconditionally. The outcome is that it doesn't check for the
>> conditions that would necessitate the overlay cursor, meaning
>> that it doesn't reject cases where the native cursor mode isn't
>> supported on DCE.
>>
>> Remove the early return from dm_crtc_get_cursor_mode() for
>> DCE and instead let it perform the necessary checks and
>> return DM_CURSOR_OVERLAY_MODE. Add a later check that rejects
>> when DM_CURSOR_OVERLAY_MODE would be used with DCE.
>>
>> Fixes: 1b04dcca4fb1 ("drm/amd/display: Introduce overlay cursor mode")
>> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4600
>> Suggested-by: Leo Li <sunpeng.li@amd.com>
>> Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
>> ---
>>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 11 ++++++++---
>>   1 file changed, 8 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> index 655c9fcb078a..3e1ba5521f2b 100644
>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> @@ -12262,10 +12262,9 @@ static int dm_crtc_get_cursor_mode(struct amdgpu_device *adev,
>>   
>>   	/* Overlay cursor not supported on HW before DCN
>>   	 * DCN401 does not have the cursor-on-scaled-plane or cursor-on-yuv-plane restrictions
>> -	 * as previous DCN generations, so enable native mode on DCN401 in addition to DCE
>> +	 * as previous DCN generations, so enable native mode on DCN401
>>   	 */
>> -	if (amdgpu_ip_version(adev, DCE_HWIP, 0) == 0 ||
>> -	    amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 0, 1)) {
>> +	if (amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 0, 1)) {
>>   		*cursor_mode = DM_CURSOR_NATIVE_MODE;
>>   		return 0;
>>   	}
>> @@ -12585,6 +12584,12 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
>>   		 * need to be added for DC to not disable a plane by mistake
>>   		 */
>>   		if (dm_new_crtc_state->cursor_mode == DM_CURSOR_OVERLAY_MODE) {
>> +			if (amdgpu_ip_version(adev, DCE_HWIP, 0) == 0) {
>> +				drm_dbg(dev, "Overlay cursor not supported on DCE\n");
>> +				ret = -EINVAL;
>> +				goto fail;
>> +			}
>> +
>>   			ret = drm_atomic_add_affected_planes(state, crtc);
>>   			if (ret)
>>   				goto fail;
>> -- 
>> 2.52.0
>>
> 
> Hi,
> 
> This change lgtm.
> 
> Alex, Dan,
> Could you include this patch in the next week promotion?
> 
> Reviewed-by: Rodrigo Siqueira <siqueira@igalia.com>
> 
> Thanks
> 

This was tested in promotion test and no issues were found.