Re: [PATCH RFC 1/7] media: qcom: iris: add QC10C & P010 buffer size calculations

[Dikshita Agarwal]

On 4/8/2026 10:13 PM, Neil Armstrong wrote:
> The P010 (YUV format with 16-bits per pixel with interleaved UV)
> and QC10C (P010 compressed mode similar to QC08C) requires specific
> buffer calculations to allocate the right buffer size for DPB frames
> and frames consumed by userspace.
> 
> Similar to 8bit, the 10bit DPB frames uses QC10C format.
> 
> Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
> ---
>  drivers/media/platform/qcom/iris/iris_buffer.c | 81 +++++++++++++++++++++++++-
>  1 file changed, 80 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/platform/qcom/iris/iris_buffer.c b/drivers/media/platform/qcom/iris/iris_buffer.c
> index 9151f43bc6b9..a0e31bff8f26 100644
> --- a/drivers/media/platform/qcom/iris/iris_buffer.c
> +++ b/drivers/media/platform/qcom/iris/iris_buffer.c
> @@ -15,7 +15,9 @@
>  #define MAX_WIDTH 4096
>  #define MAX_HEIGHT 2304
>  #define Y_STRIDE_ALIGN 128
> +#define Y_STRIDE_ALIGN_P010 256
>  #define UV_STRIDE_ALIGN 128
> +#define UV_STRIDE_ALIGN_P010 256
>  #define Y_SCANLINE_ALIGN 32
>  #define UV_SCANLINE_ALIGN 16
>  #define UV_SCANLINE_ALIGN_QC08C 32
> @@ -80,6 +82,26 @@ static u32 iris_yuv_buffer_size_nv12(struct iris_inst *inst)
>  	return ALIGN(y_plane + uv_plane, PIXELS_4K);
>  }
>  
> +static u32 iris_yuv_buffer_size_p010(struct iris_inst *inst)
> +{
> +	u32 y_plane, uv_plane, y_stride, uv_stride, y_scanlines, uv_scanlines;
> +	struct v4l2_format *f;
> +
> +	if (inst->domain == DECODER)
> +		f = inst->fmt_dst;
> +	else
> +		f = inst->fmt_src;
> +
> +	y_stride = ALIGN(f->fmt.pix_mp.width * 2, Y_STRIDE_ALIGN_P010);
> +	uv_stride = ALIGN(f->fmt.pix_mp.width * 2, UV_STRIDE_ALIGN_P010);
> +	y_scanlines = ALIGN(f->fmt.pix_mp.height, Y_SCANLINE_ALIGN);
> +	uv_scanlines = ALIGN((f->fmt.pix_mp.height + 1) >> 1, UV_SCANLINE_ALIGN);
> +	y_plane = y_stride * y_scanlines;
> +	uv_plane = uv_stride * uv_scanlines;
> +
> +	return ALIGN(y_plane + uv_plane, PIXELS_4K);
> +}
> +
>  /*
>   * QC08C:
>   * Compressed Macro-tile format for NV12.
> @@ -204,6 +226,55 @@ static u32 iris_yuv_buffer_size_qc08c(struct iris_inst *inst)
>  	return ALIGN(y_meta_plane + y_plane + uv_meta_plane + uv_plane, PIXELS_4K);
>  }
>  
> +/*
> + * QC10C:
> + * Compressed Macro-tile format for TP10.
> + */
> +static u32 iris_yuv_buffer_size_qc10c(struct iris_inst *inst)
> +{
> +	u32 y_stride, y_buf_height;
> +	u32 uv_stride, uv_buf_height;
> +	u32 y_md_stride, y_md_height;
> +	u32 uv_md_stride, uv_md_height;
> +	u32 y_data_size, uv_data_size;
> +	u32 y_md_size, uv_md_size;
> +	struct v4l2_format *f = NULL;
> +
> +	if (inst->domain == DECODER)
> +		f = inst->fmt_dst;
> +	else
> +		f = inst->fmt_src;
> +
> +	y_stride = ALIGN(ALIGN(f->fmt.pix_mp.width, 192) * 4 / 3,
> +			 Y_STRIDE_ALIGN_P010);

Y_STRIDE_ALIGN_P010 is being used for both P010 and QC10C, lets keep it
Y_STRIDE_ALIGN_10_BIT ? or something similar ?

> +	y_buf_height = ALIGN(f->fmt.pix_mp.height, UV_SCANLINE_ALIGN);

why not call it y_scanlines only?

> +
> +	y_data_size = ALIGN(y_stride * y_buf_height, PIXELS_4K);

s/y_data_size/y_plane ?

> +
> +	uv_stride = ALIGN(ALIGN(f->fmt.pix_mp.width, 192) * 4 / 3,
> +			  UV_STRIDE_ALIGN_P010);
> +	uv_buf_height = ALIGN((f->fmt.pix_mp.height + 1) / 2,
> +			      UV_SCANLINE_ALIGN);

s/uv_buf_height/uv_scanline?

> +
> +	uv_data_size = ALIGN(uv_stride * uv_buf_height, PIXELS_4K);

s/uv_data_size/uv_plane?

Pls keep all these names consistent with other functions, applies to below
variables as well.


Thanks,
Dikshita

> +
> +	y_md_stride = ALIGN(DIV_ROUND_UP(f->fmt.pix_mp.width, 48),
> +			    META_STRIDE_ALIGNED);
> +	y_md_height = ALIGN(DIV_ROUND_UP(f->fmt.pix_mp.height, 4),
> +			    META_SCANLINE_ALIGNED);
> +
> +	y_md_size = ALIGN(y_md_stride * y_md_height, PIXELS_4K);
> +
> +	uv_md_stride = ALIGN(DIV_ROUND_UP((f->fmt.pix_mp.width + 1) / 2, 24),
> +			     META_STRIDE_ALIGNED);
> +	uv_md_height = ALIGN(DIV_ROUND_UP((f->fmt.pix_mp.height + 1) / 2, 4),
> +			     META_SCANLINE_ALIGNED);
> +
> +	uv_md_size = ALIGN(uv_md_stride * uv_md_height, PIXELS_4K);
> +
> +	return y_data_size + uv_data_size + y_md_size + uv_md_size;
> +}
> +
>  static u32 iris_dec_bitstream_buffer_size(struct iris_inst *inst)
>  {
>  	struct platform_inst_caps *caps = inst->core->iris_platform_data->inst_caps;
> @@ -268,10 +339,18 @@ int iris_get_buffer_size(struct iris_inst *inst,
>  		case BUF_OUTPUT:
>  			if (inst->fmt_dst->fmt.pix_mp.pixelformat == V4L2_PIX_FMT_QC08C)
>  				return iris_yuv_buffer_size_qc08c(inst);
> +			else if (inst->fmt_dst->fmt.pix_mp.pixelformat == V4L2_PIX_FMT_QC10C)
> +				return iris_yuv_buffer_size_qc10c(inst);
> +			else if (inst->fmt_dst->fmt.pix_mp.pixelformat == V4L2_PIX_FMT_P010)
> +				return iris_yuv_buffer_size_p010(inst);
>  			else
>  				return iris_yuv_buffer_size_nv12(inst);
>  		case BUF_DPB:
> -			return iris_yuv_buffer_size_qc08c(inst);
> +			if (inst->fmt_dst->fmt.pix_mp.pixelformat == V4L2_PIX_FMT_QC10C ||
> +			    inst->fmt_dst->fmt.pix_mp.pixelformat == V4L2_PIX_FMT_P010)

Please introduce one API, is_10bit_format and use that here instead.

Thanks,
Dikshita
> +				return iris_yuv_buffer_size_qc10c(inst);
> +			else
> +				return iris_yuv_buffer_size_qc08c(inst);
>  		default:
>  			return 0;
>  		}
>