[PATCH 0/3] Xilinx 8-bit color depth YCbCr 4:2:0 media bus format

[PATCH 0/3] Xilinx 8-bit color depth YCbCr 4:2:0 media bus format

[Rohit Athavale]

This patch set adds a vendor specific custom YCbCr 4:2:0 format. The way
Xilinx Video IP sends data over the bus makes it unrepresented by existing
media bus formats.

YCbCr 4:2:0 transmission over the bus does not slice Chroma and Luma
components over the bus width. Instead it sends sub-sampled Chroma when
present along with the Luma component, otherwise zero padded Luma only
data is sent.

The first patch  (1/3) adds the format to the uapi header file.
The second patch (2/3) adds the format to the table in xilinx-vip.c.
The third patch  (3/3) updates the subdev format doc file.

Rohit Athavale (3):
  uapi: media-bus-format: Add Xilinx specific YCbCr 4:2:0 media bus
    format
  media: xilinx-vip: Add 8-bit YCbCr 4:2:0 to formats table
  Documentation: subdev-formats: Add Xilinx YCbCr to Vendor specific
    area

 Documentation/media/uapi/v4l/subdev-formats.rst | 5 +++++
 drivers/media/platform/xilinx/xilinx-vip.c      | 3 +++
 include/uapi/linux/media-bus-format.h           | 4 +++-
 3 files changed, 11 insertions(+), 1 deletion(-)

-- 
1.9.1

[PATCH 1/3] uapi: media-bus-format: Add Xilinx specific YCbCr 4:2:0 media bus format

[Rohit Athavale]

This commit adds Xilinx Video IP specific 8-bit color depth YCbCr 4:2:0
to the media bus format uapi.

Signed-off-by: Rohit Athavale <rathaval@xilinx.com>
---
 include/uapi/linux/media-bus-format.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/media-bus-format.h b/include/uapi/linux/media-bus-format.h
index ef6fb30..6f65607 100644
--- a/include/uapi/linux/media-bus-format.h
+++ b/include/uapi/linux/media-bus-format.h
@@ -143,10 +143,12 @@
 /* JPEG compressed formats - next is	0x4002 */
 #define MEDIA_BUS_FMT_JPEG_1X8			0x4001
 
-/* Vendor specific formats - next is	0x5002 */
+/* Vendor specific formats - next is	0x5003 */
 
 /* S5C73M3 sensor specific interleaved UYVY and JPEG */
 #define MEDIA_BUS_FMT_S5C_UYVY_JPEG_1X8		0x5001
+/* Xilinx IP Specific 8-bit YCbCr 4:2:0 */
+#define MEDIA_BUS_FMT_XLNX8_VUY420_1X24		0x5002
 
 /* HSV - next is	0x6002 */
 #define MEDIA_BUS_FMT_AHSV8888_1X32		0x6001
-- 
1.9.1

Re: [PATCH 1/3] uapi: media-bus-format: Add Xilinx specific YCbCr 4:2:0 media bus format

[Laurent Pinchart]

Hi Rohit,

Thank you for the patch.

On Wednesday 09 Aug 2017 11:27:52 Rohit Athavale wrote:
> This commit adds Xilinx Video IP specific 8-bit color depth YCbCr 4:2:0
> to the media bus format uapi.
> 
> Signed-off-by: Rohit Athavale <rathaval@xilinx.com>
> ---
>  include/uapi/linux/media-bus-format.h | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/include/uapi/linux/media-bus-format.h
> b/include/uapi/linux/media-bus-format.h index ef6fb30..6f65607 100644
> --- a/include/uapi/linux/media-bus-format.h
> +++ b/include/uapi/linux/media-bus-format.h
> @@ -143,10 +143,12 @@
>  /* JPEG compressed formats - next is	0x4002 */
>  #define MEDIA_BUS_FMT_JPEG_1X8			0x4001
> 
> -/* Vendor specific formats - next is	0x5002 */
> +/* Vendor specific formats - next is	0x5003 */
> 
>  /* S5C73M3 sensor specific interleaved UYVY and JPEG */
>  #define MEDIA_BUS_FMT_S5C_UYVY_JPEG_1X8		0x5001
> +/* Xilinx IP Specific 8-bit YCbCr 4:2:0 */
> +#define MEDIA_BUS_FMT_XLNX8_VUY420_1X24		0x5002

Is this really a Xilinx-specific format ? I think it would make sense to 
define it as a standard YUV format.

>  /* HSV - next is	0x6002 */
>  #define MEDIA_BUS_FMT_AHSV8888_1X32		0x6001

-- 
Regards,

Laurent Pinchart

[PATCH 2/3] media: xilinx-vip: Add 8-bit YCbCr 4:2:0 to formats table

[Rohit Athavale]

Add Xilinx YCbCr 4:2:0 to xvip formats table. This commit
will allow driver to setup media pad codes to YUV 420
via DT properties.

Signed-off-by: Rohit Athavale <rathaval@xilinx.com>
---
 drivers/media/platform/xilinx/xilinx-vip.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/media/platform/xilinx/xilinx-vip.c b/drivers/media/platform/xilinx/xilinx-vip.c
index 3112591..37b80bf 100644
--- a/drivers/media/platform/xilinx/xilinx-vip.c
+++ b/drivers/media/platform/xilinx/xilinx-vip.c
@@ -15,6 +15,7 @@
 #include <linux/clk.h>
 #include <linux/export.h>
 #include <linux/kernel.h>
+#include <linux/media-bus-format.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 
@@ -27,6 +28,8 @@
  */
 
 static const struct xvip_video_format xvip_video_formats[] = {
+	{ XVIP_VF_YUV_420, 8, NULL, MEDIA_BUS_FMT_XLNX8_VUY420_1X24,
+	  2, V4L2_PIX_FMT_NV12, "4:2:0, semi-planar, YUYV" },
 	{ XVIP_VF_YUV_422, 8, NULL, MEDIA_BUS_FMT_UYVY8_1X16,
 	  2, V4L2_PIX_FMT_YUYV, "4:2:2, packed, YUYV" },
 	{ XVIP_VF_YUV_444, 8, NULL, MEDIA_BUS_FMT_VUY8_1X24,
-- 
1.9.1

Re: [PATCH 2/3] media: xilinx-vip: Add 8-bit YCbCr 4:2:0 to formats table

[Laurent Pinchart]

Hi Rohit,

Thank you for the patch.

On Wednesday 09 Aug 2017 11:27:53 Rohit Athavale wrote:
> Add Xilinx YCbCr 4:2:0 to xvip formats table. This commit
> will allow driver to setup media pad codes to YUV 420
> via DT properties.
> 
> Signed-off-by: Rohit Athavale <rathaval@xilinx.com>
> ---
>  drivers/media/platform/xilinx/xilinx-vip.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/media/platform/xilinx/xilinx-vip.c
> b/drivers/media/platform/xilinx/xilinx-vip.c index 3112591..37b80bf 100644
> --- a/drivers/media/platform/xilinx/xilinx-vip.c
> +++ b/drivers/media/platform/xilinx/xilinx-vip.c
> @@ -15,6 +15,7 @@
>  #include <linux/clk.h>
>  #include <linux/export.h>
>  #include <linux/kernel.h>
> +#include <linux/media-bus-format.h>

I'm pretty sure the file is included indirectly already, so this isn't 
strictly needed, but it shouldn't hurt either.

>  #include <linux/of.h>
>  #include <linux/platform_device.h>
> 
> @@ -27,6 +28,8 @@
>   */
> 
>  static const struct xvip_video_format xvip_video_formats[] = {
> +	{ XVIP_VF_YUV_420, 8, NULL, MEDIA_BUS_FMT_XLNX8_VUY420_1X24,
> +	  2, V4L2_PIX_FMT_NV12, "4:2:0, semi-planar, YUYV" },

You're mapping XVIP_VF_YUV_420 to V4L2_PIX_FMT_NV12 which has an average bpp 
of 1.5 bytes per pixel, but you're setting bpp to 2. How does that work ? You 
obviously can't express a 1.5 bpp currently in the driver, so we might need to 
extend the xvip_video_format structure with additional fields (for instance 
turning bytes per pixel into bits per pixel, but we might need per-plane 
information too).

On a side note, how does this work with VDMA ? The latest VDMA version I 
checked (v6.2, a while ago) didn't seem to support planar formats. Has it 
changed in more recent versions ? Doesn't it require changes in the xilinx-vip 
driver ?

>  	{ XVIP_VF_YUV_422, 8, NULL, MEDIA_BUS_FMT_UYVY8_1X16,
>  	  2, V4L2_PIX_FMT_YUYV, "4:2:2, packed, YUYV" },
>  	{ XVIP_VF_YUV_444, 8, NULL, MEDIA_BUS_FMT_VUY8_1X24,

-- 
Regards,

Laurent Pinchart

[PATCH 3/3] Documentation: subdev-formats: Add Xilinx YCbCr to Vendor specific area

[Rohit Athavale]

This commit adds the custom Xilinx IP specific 8-bit YCbCr 4:2:0
to the custom formats area in the subdev-formats documentation.

Signed-off-by: Rohit Athavale <rathaval@xilinx.com>
---
 Documentation/media/uapi/v4l/subdev-formats.rst | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/media/uapi/v4l/subdev-formats.rst b/Documentation/media/uapi/v4l/subdev-formats.rst
index 8e73bb0..141a837 100644
--- a/Documentation/media/uapi/v4l/subdev-formats.rst
+++ b/Documentation/media/uapi/v4l/subdev-formats.rst
@@ -7483,3 +7483,8 @@ formats.
       - 0x5001
       - Interleaved raw UYVY and JPEG image format with embedded meta-data
 	used by Samsung S3C73MX camera sensors.
+    * .. _MEDIA_BUS_FMT_XLNX8_VUY420_1X24:
+
+      - MEDIA_BUS_FMT_XLNX8_VUY420_1X24
+      - 0x5002
+      - Xilinx IP specific 8-bit color depth YCbCr 4:2:0 used by Xilinx Video IP.
-- 
1.9.1

Re: [PATCH 3/3] Documentation: subdev-formats: Add Xilinx YCbCr to Vendor specific area

[Laurent Pinchart]

Hi Rohit,

Thank you for the patch.

On Wednesday 09 Aug 2017 11:27:54 Rohit Athavale wrote:
> This commit adds the custom Xilinx IP specific 8-bit YCbCr 4:2:0
> to the custom formats area in the subdev-formats documentation.
> 
> Signed-off-by: Rohit Athavale <rathaval@xilinx.com>
> ---
>  Documentation/media/uapi/v4l/subdev-formats.rst | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/Documentation/media/uapi/v4l/subdev-formats.rst
> b/Documentation/media/uapi/v4l/subdev-formats.rst index 8e73bb0..141a837
> 100644
> --- a/Documentation/media/uapi/v4l/subdev-formats.rst
> +++ b/Documentation/media/uapi/v4l/subdev-formats.rst
> @@ -7483,3 +7483,8 @@ formats.
>        - 0x5001
>        - Interleaved raw UYVY and JPEG image format with embedded meta-data
>  	used by Samsung S3C73MX camera sensors.
> +    * .. _MEDIA_BUS_FMT_XLNX8_VUY420_1X24:
> +
> +      - MEDIA_BUS_FMT_XLNX8_VUY420_1X24
> +      - 0x5002
> +      - Xilinx IP specific 8-bit color depth YCbCr 4:2:0 used by Xilinx
> Video IP.

You need to document this format in more details, with a table explaining how 
bits are transferred on the bus, the same way the standard YUV formats are 
documented.

-- 
Regards,

Laurent Pinchart