Re: [PATCH 2/2] nouveau/disp: fix post-gsp build on 32-bit arm.

[Danilo Krummrich <dakr@xxxxxxxxxx>]

On 10/30/23 02:28, Dave Airlie wrote:
> From: Dave Airlie <airlied@xxxxxxxxxx>
>
> This converts a bunch of divides into the proper macros.
>
> Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx>

Reviewed-by: Danilo Krummrich <dakr@xxxxxxxxxx>

> ---
>   drivers/gpu/drm/nouveau/dispnv50/disp.c | 24 +++++++++++++-----------
>   1 file changed, 13 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> index d2be40337b92..7840b6428afb 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> @@ -1644,7 +1644,7 @@ nv50_sor_dp_watermark_sst(struct nouveau_encoder *outp,
>   	// 0 active symbols. This may cause HW hang. Bug 200379426
>   	//
>   	if ((bEnableDsc) &&
> -		((pixelClockHz * depth) < ((8 * minRate * outp->dp.link_nr * DSC_FACTOR) / 64)))
> +	    ((pixelClockHz * depth) < div_u64(8 * minRate * outp->dp.link_nr * DSC_FACTOR, 64)))
>   	{
>   		return false;
>   	}
> @@ -1654,20 +1654,20 @@ nv50_sor_dp_watermark_sst(struct nouveau_encoder *outp,
>   	//	For auto mode the watermark calculation does not need to track accumulated error the
>   	//	formulas for manual mode will not work.  So below calculation was extracted from the DTB.
>   	//
> -	ratioF = ((u64)pixelClockHz * depth * PrecisionFactor) / DSC_FACTOR;
> +	ratioF = div_u64((u64)pixelClockHz * depth * PrecisionFactor, DSC_FACTOR);
>   
> -	ratioF /= 8 * (u64) minRate * outp->dp.link_nr;
> +	ratioF = div_u64(ratioF, 8 * (u64) minRate * outp->dp.link_nr);
>   
>   	if (PrecisionFactor < ratioF) // Assert if we will end up with a negative number in below
>   		return false;
>   
> -	watermarkF = ratioF * tuSize * (PrecisionFactor - ratioF)  / PrecisionFactor;
> -	waterMark = (unsigned)(watermarkAdjust + ((2 * (depth * PrecisionFactor / (8 * numLanesPerLink * DSC_FACTOR)) + watermarkF) / PrecisionFactor));
> +	watermarkF = div_u64(ratioF * tuSize * (PrecisionFactor - ratioF), PrecisionFactor);
> +	waterMark = (unsigned)(watermarkAdjust + (div_u64(2 * div_u64(depth * PrecisionFactor, 8 * numLanesPerLink * DSC_FACTOR) + watermarkF, PrecisionFactor)));
>   
>   	//
>   	//  Bounds check the watermark
>   	//
> -	numSymbolsPerLine = (surfaceWidth * depth) / (8 * outp->dp.link_nr * DSC_FACTOR);
> +	numSymbolsPerLine = div_u64(surfaceWidth * depth, 8 * outp->dp.link_nr * DSC_FACTOR);
>   
>   	if (WARN_ON(waterMark > 39 || waterMark > numSymbolsPerLine))
>   		return false;
> @@ -1688,11 +1688,13 @@ nv50_sor_dp_watermark_sst(struct nouveau_encoder *outp,
>   	surfaceWidthPerLink = surfaceWidth;
>   
>   	//Extra bits sent due to pixel steering
> -	PixelSteeringBits = (surfaceWidthPerLink % numLanesPerLink) ? (((numLanesPerLink - surfaceWidthPerLink % numLanesPerLink) * depth) / DSC_FACTOR) : 0;
> +	u32 remain;
> +	div_u64_rem(surfaceWidthPerLink, numLanesPerLink, &remain);
> +	PixelSteeringBits = remain ? div_u64((numLanesPerLink - remain) * depth, DSC_FACTOR) : 0;
>   
>   	BlankingBits += PixelSteeringBits;
> -	NumBlankingLinkClocks = (u64)BlankingBits * PrecisionFactor / (8 * numLanesPerLink);
> -	MinHBlank = (u32)(NumBlankingLinkClocks * pixelClockHz/ minRate / PrecisionFactor);
> +	NumBlankingLinkClocks = div_u64((u64)BlankingBits * PrecisionFactor, (8 * numLanesPerLink));
> +	MinHBlank = (u32)(div_u64(div_u64(NumBlankingLinkClocks * pixelClockHz, minRate), PrecisionFactor));
>   	MinHBlank += 12;
>   
>   	if (WARN_ON(MinHBlank > rasterWidth - surfaceWidth))
> @@ -1703,7 +1705,7 @@ nv50_sor_dp_watermark_sst(struct nouveau_encoder *outp,
>   		return false;
>   
>   
> -	hblank_symbols = (s32)(((u64)(rasterWidth - surfaceWidth - MinHBlank) * minRate) / pixelClockHz);
> +	hblank_symbols = (s32)(div_u64((u64)(rasterWidth - surfaceWidth - MinHBlank) * minRate, pixelClockHz));
>   
>   	//reduce HBlank Symbols to account for secondary data packet
>   	hblank_symbols -= 1; //Stuffer latency to send BS
> @@ -1722,7 +1724,7 @@ nv50_sor_dp_watermark_sst(struct nouveau_encoder *outp,
>   	}
>   	else
>   	{
> -		vblank_symbols = (s32)(((u64)(surfaceWidth - 40) * minRate) /  pixelClockHz) - 1;
> +		vblank_symbols = (s32)((div_u64((u64)(surfaceWidth - 40) * minRate, pixelClockHz))) - 1;
>   
>   		vblank_symbols -= numLanesPerLink == 1 ? 39  : numLanesPerLink == 2 ? 21 : 12;
>   	}