[PATCH] media: verisilicon: Do not enable G2 postproc downscale if source is narrower than destination

[Benjamin Gaignard]

Le 24/08/2023 à 03:39, Marek Vasut a écrit :
> In case of encoded input VP9 data width that is not multiple of macroblock
> size, which is 16 (e.g. 1080x1920 frames, where 1080 is multiple of 8), the
> width is padded to be a multiple of macroblock size (for 1080x1920 frames,
> that is 1088x1920).
>
> The hantro_postproc_g2_enable() checks whether the encoded data width is
> equal to decoded frame width, and if not, enables down-scale mode. For a
> frame where input is 1080x1920 and output is 1088x1920, this is incorrect
> as no down-scale happens, the frame is only padded. Enabling the down-scale
> mode in this case results in corrupted frames.
>
> Fix this by adjusting the check to test whether encoded data width is
> greater than decoded frame width, and only in that case enable the
> down-scale mode.
>
> To generate input test data to trigger this bug, use e.g.:
> $ gst-launch-1.0 videotestsrc ! video/x-raw,width=272,height=256,format=I420 ! \
>                   vp9enc ! matroskamux ! filesink location=/tmp/test.vp9
> To trigger the bug upon decoding (note that the NV12 must be forced, as
> that assures the output data would pass the G2 postproc):
> $ gst-launch-1.0 filesrc location=/tmp/test.vp9 ! matroskademux ! vp9parse ! \
>                   v4l2slvp9dec ! video/x-raw,format=NV12 ! videoconvert ! fbdevsink

I had propose the same patch in my series in July:
https://patchwork.kernel.org/project/linux-media/patch/20230705121056.37017-8-benjamin.gaignard@collabora.com/

Reviewed-by: Benjamin Gaignard <benjamin.gaignard at collabora.com>

>
> Fixes: 79c987de8b35 ("media: hantro: Use post processor scaling capacities")
> Signed-off-by: Marek Vasut <marex at denx.de>
> ---
> Cc: Adam Ford <aford173 at gmail.com>
> Cc: Benjamin Gaignard <benjamin.gaignard at collabora.com>
> Cc: Ezequiel Garcia <ezequiel at vanguardiasur.com.ar>
> Cc: Mauro Carvalho Chehab <mchehab at kernel.org>
> Cc: Philipp Zabel <p.zabel at pengutronix.de>
> Cc: linux-media at vger.kernel.org
> Cc: linux-rockchip at lists.infradead.org
> ---
>   drivers/media/platform/verisilicon/hantro_postproc.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/verisilicon/hantro_postproc.c b/drivers/media/platform/verisilicon/hantro_postproc.c
> index 0224ff68ab3fc..64d6fb852ae9b 100644
> --- a/drivers/media/platform/verisilicon/hantro_postproc.c
> +++ b/drivers/media/platform/verisilicon/hantro_postproc.c
> @@ -107,7 +107,7 @@ static void hantro_postproc_g1_enable(struct hantro_ctx *ctx)
>   
>   static int down_scale_factor(struct hantro_ctx *ctx)
>   {
> -	if (ctx->src_fmt.width == ctx->dst_fmt.width)
> +	if (ctx->src_fmt.width <= ctx->dst_fmt.width)
>   		return 0;
>   
>   	return DIV_ROUND_CLOSEST(ctx->src_fmt.width, ctx->dst_fmt.width);