Re: [PATCH RFC 4/7] media: qcom: iris: vdec: update size and stride calculations for 10bit formats

[Neil Armstrong <neil.armstrong@linaro.org>]

On 4/10/26 12:10, Vishnu Reddy wrote:
> 
> On 4/8/2026 10:13 PM, Neil Armstrong wrote:
>> Update the gen2 response and vdec s_fmt code to take in account
>> the P010 and QC010 when calculating the width, height and stride.
>>
>> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
>> ---
>>   .../platform/qcom/iris/iris_hfi_gen2_response.c     | 19 ++++++++++++++++---
>>   drivers/media/platform/qcom/iris/iris_vdec.c        | 21 ++++++++++++++++++---
>>   2 files changed, 34 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/media/platform/qcom/iris/iris_hfi_gen2_response.c b/drivers/media/platform/qcom/iris/iris_hfi_gen2_response.c
>> index 8e19f61bbbf9..d268149191ea 100644
>> --- a/drivers/media/platform/qcom/iris/iris_hfi_gen2_response.c
>> +++ b/drivers/media/platform/qcom/iris/iris_hfi_gen2_response.c
>> @@ -542,9 +542,22 @@ static void iris_hfi_gen2_read_input_subcr_params(struct iris_inst *inst)
>>       pixmp_ip->width = width;
>>       pixmp_ip->height = height;
>> -    pixmp_op->width = ALIGN(width, 128);
>> -    pixmp_op->height = ALIGN(height, 32);
>> -    pixmp_op->plane_fmt[0].bytesperline = ALIGN(width, 128);
>> +    pixmp_op->width = pixmp_op->pixelformat == V4L2_PIX_FMT_QC10C ?
>> +        ALIGN(width, 192) : ALIGN(width, 128);
>> +    pixmp_op->height = pixmp_op->pixelformat == V4L2_PIX_FMT_QC10C ?
>> +        ALIGN(height, 16) : ALIGN(height, 32);
>> +    switch (pixmp_op->pixelformat) {
>> +    case V4L2_PIX_FMT_P010:
>> +        pixmp_op->plane_fmt[0].bytesperline = ALIGN(width * 2, 256);
>> +        break;
>> +    case V4L2_PIX_FMT_QC10C:
>> +        pixmp_op->plane_fmt[0].bytesperline = ALIGN(ALIGN(width, 192) * 4 / 3, 256);
>> +        break;
>> +    case V4L2_PIX_FMT_NV12:
>> +    case V4L2_PIX_FMT_QC08C:
>> +        pixmp_op->plane_fmt[0].bytesperline = ALIGN(width, 128);
>> +        break;
>> +    }
>>       pixmp_op->plane_fmt[0].sizeimage = iris_get_buffer_size(inst, BUF_OUTPUT);
>>       matrix_coeff = subsc_params.color_info & 0xFF;
>> diff --git a/drivers/media/platform/qcom/iris/iris_vdec.c b/drivers/media/platform/qcom/iris/iris_vdec.c
>> index 719217399a30..ca0518c27834 100644
>> --- a/drivers/media/platform/qcom/iris/iris_vdec.c
>> +++ b/drivers/media/platform/qcom/iris/iris_vdec.c
>> @@ -272,10 +272,25 @@ int iris_vdec_s_fmt(struct iris_inst *inst, struct v4l2_format *f)
>>           fmt = inst->fmt_dst;
>>           fmt->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
>>           fmt->fmt.pix_mp.pixelformat = f->fmt.pix_mp.pixelformat;
>> -        fmt->fmt.pix_mp.width = ALIGN(f->fmt.pix_mp.width, 128);
>> -        fmt->fmt.pix_mp.height = ALIGN(f->fmt.pix_mp.height, 32);
>> +        codec_align = f->fmt.pix_mp.pixelformat == V4L2_PIX_FMT_QC10C ? 192 : 128;
>> +        fmt->fmt.pix_mp.width = ALIGN(f->fmt.pix_mp.width, codec_align);
>> +        codec_align = f->fmt.pix_mp.pixelformat == V4L2_PIX_FMT_QC10C ? 16 : 32;
>> +        fmt->fmt.pix_mp.height = ALIGN(f->fmt.pix_mp.height, codec_align);
>>           fmt->fmt.pix_mp.num_planes = 1;
>> -        fmt->fmt.pix_mp.plane_fmt[0].bytesperline = ALIGN(f->fmt.pix_mp.width, 128);
>> +        switch (f->fmt.pix_mp.pixelformat) {
>> +        case V4L2_PIX_FMT_P010:
>> +            fmt->fmt.pix_mp.plane_fmt[0].bytesperline =
>> +                ALIGN(f->fmt.pix_mp.width * 2, 256);
>> +            break;
>> +        case V4L2_PIX_FMT_QC10C:
>> +            fmt->fmt.pix_mp.plane_fmt[0].bytesperline =
>> +                ALIGN(f->fmt.pix_mp.width * 4 / 3, 256);
>> +            break;
>> +        case V4L2_PIX_FMT_NV12:
>> +        case V4L2_PIX_FMT_QC08C:
>> +            fmt->fmt.pix_mp.plane_fmt[0].bytesperline = f->fmt.pix_mp.width;
> In the removed code, bytesperline for NV12 and QC08C was aligned to 128 bytes.
> In the new code, Is that alignment missed or not required?

The alignment is done right before:
	codec_align = f->fmt.pix_mp.pixelformat == V4L2_PIX_FMT_QC10C ? 192 : 128;
	fmt->fmt.pix_mp.width = ALIGN(f->fmt.pix_mp.width, codec_align);

calling ALIGN(f->fmt.pix_mp.width, 128) again is a no-op.

Thanks,
Neil

>> +            break;
>> +        }
>>           fmt->fmt.pix_mp.plane_fmt[0].sizeimage = iris_get_buffer_size(inst, BUF_OUTPUT);
>>           inst->buffers[BUF_OUTPUT].min_count = iris_vpu_buf_count(inst, BUF_OUTPUT);
>>           inst->buffers[BUF_OUTPUT].size = fmt->fmt.pix_mp.plane_fmt[0].sizeimage;
>>