Re: [PATCH RFC 2/7] media: qcom: iris: gen2: add support for 10bit decoding

[Neil Armstrong]

On 4/17/26 09:22, Dikshita Agarwal wrote:
> On 4/8/2026 10:13 PM, Neil Armstrong wrote:
> > Add the necessary plumbing into the HFi Gen2 to signal the decoder
> > the right 10bit pixel format and stride when in compressed mode.
> >
> > Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
> > ---
> >   .../platform/qcom/iris/iris_hfi_gen2_command.c     | 71 +++++++++++++++++++++-
> >   .../platform/qcom/iris/iris_hfi_gen2_defines.h     |  1 +
> >   drivers/media/platform/qcom/iris/iris_utils.c      |  4 +-
> >   3 files changed, 72 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/media/platform/qcom/iris/iris_hfi_gen2_command.c b/drivers/media/platform/qcom/iris/iris_hfi_gen2_command.c
> > index 30bfd90d423b..8e547e390fa3 100644
> > --- a/drivers/media/platform/qcom/iris/iris_hfi_gen2_command.c
> > +++ b/drivers/media/platform/qcom/iris/iris_hfi_gen2_command.c
> > @@ -481,8 +481,20 @@ static int iris_hfi_gen2_set_colorformat(struct iris_inst *inst, u32 plane)
> >   
> >   	if (inst->domain == DECODER) {
> >   		pixelformat = inst->fmt_dst->fmt.pix_mp.pixelformat;
> > -		hfi_colorformat = pixelformat == V4L2_PIX_FMT_NV12 ?
> > -			HFI_COLOR_FMT_NV12 : HFI_COLOR_FMT_NV12_UBWC;
> > +		switch (pixelformat) {
> > +		case V4L2_PIX_FMT_NV12:
> > +			hfi_colorformat = HFI_COLOR_FMT_NV12;
> > +			break;
> > +		case V4L2_PIX_FMT_QC08C:
> > +			hfi_colorformat = HFI_COLOR_FMT_NV12_UBWC;
> > +			break;
> > +		case V4L2_PIX_FMT_P010:
> > +			hfi_colorformat = HFI_COLOR_FMT_P010;
> > +			break;
> > +		case V4L2_PIX_FMT_QC10C:
> > +			hfi_colorformat = HFI_COLOR_FMT_TP10_UBWC;
> > +			break;
> > +		};
> >   	} else {
> >   		pixelformat = inst->fmt_src->fmt.pix_mp.pixelformat;
> >   		hfi_colorformat = pixelformat == V4L2_PIX_FMT_NV12 ?
> > @@ -517,7 +529,8 @@ static int iris_hfi_gen2_set_linear_stride_scanline(struct iris_inst *inst, u32
> >   	stride_uv = stride_y;
> >   	scanline_uv = scanline_y / 2;
> >   
> > -	if (pixelformat != V4L2_PIX_FMT_NV12)
> > +	if (pixelformat != V4L2_PIX_FMT_NV12 &&
> > +	    pixelformat != V4L2_PIX_FMT_P010)
> >   		return 0;
> >   
> >   	payload[0] = stride_y << 16 | scanline_y;
> > @@ -532,6 +545,57 @@ static int iris_hfi_gen2_set_linear_stride_scanline(struct iris_inst *inst, u32
> >   						  sizeof(u64));
> >   }
> >   
> > +static int iris_hfi_gen2_set_ubwc_stride_scanline(struct iris_inst *inst, u32 plane)
> > +{
> > +	u32 meta_stride_y, meta_scanline_y, meta_stride_uv, meta_scanline_uv;
> > +	u32 stride_y, scanline_y, stride_uv, scanline_uv;
> > +	u32 port = iris_hfi_gen2_get_port(inst, plane);
> > +	u32 pixelformat, width, height;
> > +	u32 payload[4];
> > +
> > +	pixelformat = inst->fmt_dst->fmt.pix_mp.pixelformat;
> > +	width = inst->fmt_dst->fmt.pix_mp.width;
> > +	height = inst->fmt_dst->fmt.pix_mp.height;
>
> This HFI is only applicable to AV1, you might see some corruption due to
> this. Please check.

This is what I saw looking at donwstream, but I had not implemented this initially
but I got some corruption with some different width/height, which was solved adding
this command.
I guess this in-firmware calculations are not exactly the same the DRM driver expects.

Honestly I think it's preferable to sync the stride/scanlines calculations between the
driver and the firmware.
For example I used the same "ALIGN(width, 192)" for the v2 iris patchset which was wrong
because ALIGN only works on Power Of Two number but it still worked because this HFI
HFI_PROP_UBWC_STRIDE_SCANLINE command was called with the wrong aligned width.

Neil

> Thanks,
> Dikshita