Re: [PATCH] drm/i915/scaler: Update Pipe src size check in skl_update_scaler

["Nautiyal, Ankit K" <ankit.k.nautiyal@intel.com>]

On 3/15/2024 1:56 PM, Ville Syrjälä wrote:
> On Wed, Mar 13, 2024 at 08:08:25PM +0530, Ankit Nautiyal wrote:
>> For Earlier platforms, the Pipe source size is 12-bits so
>> max pipe source width and height is 4096. For newer platforms it is
>> 13-bits so theoretically max width/height is 8192. For few of the
>> earlier platforms the scaler did not use all bits of the PIPESRC,
>> so max scaler source size was used to make that the pipe source
>> size is programmed within limits, before using scaler.
>>
>> This creates a problem, for MTL where scaler source size is 4096, but
>> max pipe source width can theroretically be 8192.
>>
>> Switch the check to use the max scaler destination size, which closely
>> match the limits.
>>
>> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Thanks for the review, pushed to drm-intel-next.

Regards,

Ankit

>
>> ---
>>   drivers/gpu/drm/i915/display/skl_scaler.c | 7 ++++---
>>   1 file changed, 4 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/skl_scaler.c b/drivers/gpu/drm/i915/display/skl_scaler.c
>> index 8a934bada624..baa601d27815 100644
>> --- a/drivers/gpu/drm/i915/display/skl_scaler.c
>> +++ b/drivers/gpu/drm/i915/display/skl_scaler.c
>> @@ -213,10 +213,11 @@ skl_update_scaler(struct intel_crtc_state *crtc_state, bool force_detach,
>>   	 * The pipe scaler does not use all the bits of PIPESRC, at least
>>   	 * on the earlier platforms. So even when we're scaling a plane
>>   	 * the *pipe* source size must not be too large. For simplicity
>> -	 * we assume the limits match the scaler source size limits. Might
>> -	 * not be 100% accurate on all platforms, but good enough for now.
>> +	 * we assume the limits match the scaler destination size limits.
>> +	 * Might not be 100% accurate on all platforms, but good enough for
>> +	 * now.
>>   	 */
>> -	if (pipe_src_w > max_src_w || pipe_src_h > max_src_h) {
>> +	if (pipe_src_w > max_dst_w || pipe_src_h > max_dst_h) {
>>   		drm_dbg_kms(&dev_priv->drm,
>>   			    "scaler_user index %u.%u: pipe src size %ux%u "
>>   			    "is out of scaler range\n",
>> -- 
>> 2.40.1