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

From: Vishnu Reddy

Date: Fri Apr 10 2026 - 09:02:50 EST



On 4/10/2026 5:29 PM, Neil Armstrong wrote:
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@xxxxxxxxxx>
---
  .../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.

Here f->fmt.pix_mp.width is not aligned, fmt->fmt.pix_mp.width is aligned.
It should be fmt->fmt.pix_mp.plane_fmt[0].bytesperline = fmt->fmt.pix_mp.width.

Thanks,
Vishnu Reddy
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;