Hi Hans, Thanks for your feedback.
On 2018-09-14 10:47:41 +0200, Hans Verkuil wrote: > On 09/14/2018 04:13 AM, Niklas Söderlund wrote: > > The Gen3 datasheets lists specific alignment restrictions compared to > > Gen2. This was overlooked when adding Gen3 support as no problematic > > configuration was encountered. However when adding support for Gen3 Up > > Down Scaler (UDS) strange issues could be observed for odd widths > > without taking this limit into consideration. > > > > Signed-off-by: Niklas Söderlund <[email protected]> > > --- > > drivers/media/platform/rcar-vin/rcar-v4l2.c | 15 +++++++++++++++ > > 1 file changed, 15 insertions(+) > > > > diff --git a/drivers/media/platform/rcar-vin/rcar-v4l2.c > > b/drivers/media/platform/rcar-vin/rcar-v4l2.c > > index dc77682b47857c97..2fc2a05eaeacb134 100644 > > --- a/drivers/media/platform/rcar-vin/rcar-v4l2.c > > +++ b/drivers/media/platform/rcar-vin/rcar-v4l2.c > > @@ -673,6 +673,21 @@ static void rvin_mc_try_format(struct rvin_dev *vin, > > pix->quantization = V4L2_MAP_QUANTIZATION_DEFAULT(true, pix->colorspace, > > pix->ycbcr_enc); > > > > + switch (vin->format.pixelformat) { > > + case V4L2_PIX_FMT_NV16: > > + pix->width = ALIGN(pix->width, 0x80); > > + break; > > + case V4L2_PIX_FMT_YUYV: > > + case V4L2_PIX_FMT_UYVY: > > + case V4L2_PIX_FMT_RGB565: > > + case V4L2_PIX_FMT_XRGB555: > > + pix->width = ALIGN(pix->width, 0x40); > > + break; > > + default: > > + pix->width = ALIGN(pix->width, 0x20); > > + break; > > + } > > + > > rvin_format_align(vin, pix); > > } > > > > > > This looks weird. So for NV16 the width must be a multiple of 128, > do I read that correctly? > > Are you sure you don't mean bytesperline? > > And if it really is the width, doesn't this place very big constraints > on the vin driver? If you don't want/need the UDS, then I can imagine > that you don't want these alignments. Thanks for brining this up, after more carefully reading the datasheet (which is a bit ambiguous in this section) I figured out that this is to strict. Will rewrite this patch for v2. -- Regards, Niklas Söderlund
