[PATCH v2 2/6] media: qcom: iris: add QC10C & P010 buffer size calculations

From: Neil Armstrong

Date: Fri Apr 17 2026 - 05:54:26 EST

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 | 195 ++++++++++++++++++++++++-
1 file changed, 194 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..23a3e9a9c383 100644
--- a/drivers/media/platform/qcom/iris/iris_buffer.c
+++ b/drivers/media/platform/qcom/iris/iris_buffer.c
@@ -15,8 +15,11 @@
#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 Y_SCANLINE_ALIGN_QC10C 16
#define UV_SCANLINE_ALIGN 16
#define UV_SCANLINE_ALIGN_QC08C 32
#define META_STRIDE_ALIGNED 64
@@ -80,6 +83,63 @@ static u32 iris_yuv_buffer_size_nv12(struct iris_inst *inst)
return ALIGN(y_plane + uv_plane, PIXELS_4K);
}

+/*
+ * P010:
+ * YUV 4:2:0 image with a plane of 10 bit Y samples followed
+ * by an interleaved U/V plane containing 10 bit 2x2 subsampled
+ * colour difference samples.
+ *
+ * <-Y/UV_Stride (aligned to 256)->
+ * <----- Width*2 ------->
+ * Y Y Y Y Y Y Y Y Y Y Y Y . . . . ^ ^
+ * Y Y Y Y Y Y Y Y Y Y Y Y . . . . | |
+ * Y Y Y Y Y Y Y Y Y Y Y Y . . . . Height |
+ * Y Y Y Y Y Y Y Y Y Y Y Y . . . . | y_scanlines (aligned to 32)
+ * Y Y Y Y Y Y Y Y Y Y Y Y . . . . | |
+ * Y Y Y Y Y Y Y Y Y Y Y Y . . . . | |
+ * Y Y Y Y Y Y Y Y Y Y Y Y . . . . | |
+ * Y Y Y Y Y Y Y Y Y Y Y Y . . . . V |
+ * . . . . . . . . . . . . . . . . |
+ * . . . . . . . . . . . . . . . . |
+ * . . . . . . . . . . . . . . . . |
+ * . . . . . . . . . . . . . . . . V
+ * U V U V U V U V U V U V . . . . ^
+ * U V U V U V U V U V U V . . . . |
+ * U V U V U V U V U V U V . . . . |
+ * U V U V U V U V U V U V . . . . uv_scanlines (aligned to 16)
+ * . . . . . . . . . . . . . . . . |
+ * . . . . . . . . . . . . . . . . V
+ * . . . . . . . . . . . . . . . . --> Buffer size aligned to 4K
+ *
+ * y_stride : Width*2 aligned to 256
+ * uv_stride : Width*2 aligned to 256
+ * y_scanlines: Height aligned to 32
+ * uv_scanlines: Height/2 aligned to 16
+ * Total size = align((y_stride * y_scanlines
+ * + uv_stride * uv_scanlines , 4096)
+ *
+ * Note: All the alignments are hardware requirements.
+ */
+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 +264,132 @@ 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:
+ * UBWC-compressed format for P010.
+ * Contains 4 planes in the following order -
+ * (A) Y_Meta_Plane
+ * (B) Y_UBWC_Plane
+ * (C) UV_Meta_Plane
+ * (D) UV_UBWC_Plane
+ *
+ * Y_Meta_Plane consists of meta information to decode compressed
+ * tile data in Y_UBWC_Plane.
+ * Y_UBWC_Plane consists of Y data in compressed macro-tile format.
+ * UBWC decoder block will use the Y_Meta_Plane data together with
+ * Y_UBWC_Plane data to produce loss-less uncompressed 10 bit Y samples.
+ *
+ * UV_Meta_Plane consists of meta information to decode compressed
+ * tile data in UV_UBWC_Plane.
+ * UV_UBWC_Plane consists of UV data in compressed macro-tile format.
+ * UBWC decoder block will use UV_Meta_Plane data together with
+ * UV_UBWC_Plane data to produce loss-less uncompressed 10 bit 2x2
+ * subsampled color difference samples.
+ *
+ * Each tile in Y_UBWC_Plane/UV_UBWC_Plane is independently decodable
+ * and randomly accessible. There is no dependency between tiles.
+ *
+ * <----- Y Meta stride -----> (aligned to 64)
+ * <-------- Width ----------> (aligned to 48)
+ * M M M M M M M M M M M M . . ^ ^
+ * M M M M M M M M M M M M . . | |
+ * M M M M M M M M M M M M . . Height |
+ * M M M M M M M M M M M M . . | Meta_Y_Scanlines (aligned to 16)
+ * M M M M M M M M M M M M . . | |
+ * M M M M M M M M M M M M . . | |
+ * M M M M M M M M M M M M . . | |
+ * M M M M M M M M M M M M . . V |
+ * . . . . . . . . . . . . . . |
+ * . . . . . . . . . . . . . . |
+ * . . . . . . . . . . . . . . -------> Buffer size aligned to 4k
+ * . . . . . . . . . . . . . . V
+ * <--Compressed tile Y stride --> (aligned to 256)
+ * <------- Width * 4/3 ---------> (aligned to 48)
+ * Y* Y* Y* Y* Y* Y* Y* Y* . . . . ^ ^
+ * Y* Y* Y* Y* Y* Y* Y* Y* . . . . | |
+ * Y* Y* Y* Y* Y* Y* Y* Y* . . . . Height |
+ * Y* Y* Y* Y* Y* Y* Y* Y* . . . . | Macro_tile_Y_Scanlines (aligned to 16)
+ * Y* Y* Y* Y* Y* Y* Y* Y* . . . . | |
+ * Y* Y* Y* Y* Y* Y* Y* Y* . . . . | |
+ * Y* Y* Y* Y* Y* Y* Y* Y* . . . . | |
+ * Y* Y* Y* Y* Y* Y* Y* Y* . . . . V |
+ * . . . . . . . . . . . . . . . . |
+ * . . . . . . . . . . . . . . . . |
+ * . . . . . . . . . . . . . . . . -------> Buffer size aligned to 4k
+ * . . . . . . . . . . . . . . . . V
+ * <---- UV Meta stride ----> (aligned to 64)
+ * <----- Width / 2 --------> (aligned to 24)
+ * M M M M M M M M M M M M . . ^ ^
+ * M M M M M M M M M M M M . . | |
+ * M M M M M M M M M M M M . . Height/2 |
+ * M M M M M M M M M M M M . . V M_UV_Scanlines (aligned to 16)
+ * . . . . . . . . . . . . . . |
+ * . . . . . . . . . . . . . . V
+ * . . . . . . . . . . . . . . -------> Buffer size aligned to 4k
+ * <--Compressed tile UV stride--> (aligned to 256)
+ * <------- Width * 4/3 ---------> (aligned to 48)
+ * U* V* U* V* U* V* U* V* . . . . ^
+ * U* V* U* V* U* V* U* V* . . . . |
+ * U* V* U* V* U* V* U* V* . . . . |
+ * U* V* U* V* U* V* U* V* . . . . UV_Scanlines (aligned to 16)
+ * . . . . . . . . . . . . . . . . |
+ * . . . . . . . . . . . . . . . . V
+ * . . . . . . . . . . . . . . . . -------> Buffer size aligned to 4k
+ *
+ * y_stride: width aligned to 256
+ * uv_stride: width aligned to 256
+ * y_scanlines: height aligned to 16
+ * uv_scanlines: height aligned to 16
+ * y_plane: buffer size aligned to 4096
+ * uv_plane: buffer size aligned to 4096
+ * y_meta_stride: width aligned to 64
+ * y_meta_scanlines: height aligned to 16
+ * y_meta_plane: buffer size aligned to 4096
+ * uv_meta_stride: width aligned to 64
+ * uv_meta_scanlines: height aligned to 16
+ * uv_meta_plane: buffer size aligned to 4096
+ *
+ * Total size = align( y_plane + uv_plane +
+ * y_meta_plane + uv_meta_plane, 4096)
+ *
+ * Note: All the alignments are hardware requirements.
+ */
+static u32 iris_yuv_buffer_size_qc10c(struct iris_inst *inst)
+{
+ u32 y_plane, uv_plane, y_stride, uv_stride;
+ u32 uv_meta_stride, uv_meta_plane;
+ u32 y_meta_stride, y_meta_plane;
+ struct v4l2_format *f = NULL;
+
+ if (inst->domain == DECODER)
+ f = inst->fmt_dst;
+ else
+ f = inst->fmt_src;
+
+ y_meta_stride = ALIGN(DIV_ROUND_UP(f->fmt.pix_mp.width, 48),
+ META_STRIDE_ALIGNED);
+ y_meta_plane = y_meta_stride * ALIGN(DIV_ROUND_UP(f->fmt.pix_mp.height, 4),
+ META_SCANLINE_ALIGNED);
+ y_meta_plane = ALIGN(y_meta_plane, PIXELS_4K);
+
+ y_stride = ALIGN(f->fmt.pix_mp.width * 4 / 3, Y_STRIDE_ALIGN_P010);
+ y_plane = ALIGN(y_stride * ALIGN(f->fmt.pix_mp.height, Y_SCANLINE_ALIGN_QC10C),
+ PIXELS_4K);
+
+ uv_meta_stride = ALIGN(DIV_ROUND_UP((f->fmt.pix_mp.width + 1) / 2, 24),
+ META_STRIDE_ALIGNED);
+ uv_meta_plane = uv_meta_stride *
+ ALIGN(DIV_ROUND_UP((f->fmt.pix_mp.height + 1) / 2, 4),
+ META_SCANLINE_ALIGNED);
+ uv_meta_plane = ALIGN(uv_meta_plane, PIXELS_4K);
+
+ uv_stride = ALIGN(f->fmt.pix_mp.width * 4 / 3, UV_STRIDE_ALIGN_P010);
+ uv_plane = ALIGN(uv_stride * ALIGN((f->fmt.pix_mp.height + 1) / 2, UV_SCANLINE_ALIGN),
+ PIXELS_4K);
+
+ return ALIGN(y_meta_plane + y_plane + uv_meta_plane + uv_plane, PIXELS_4K);
+}
+
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 +454,17 @@ 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 (iris_fmt_is_10bit(inst->fmt_dst->fmt.pix_mp.pixelformat))
+ return iris_yuv_buffer_size_qc10c(inst);
+ else
+ return iris_yuv_buffer_size_qc08c(inst);
default:
return 0;
}

--
2.34.1