Re: [PATCH v3 6/7] media: rkvdec: Add the rkvdec driver

From: Hans Verkuil <hverkuil@xs4all.nl>
To: Boris Brezillon <boris.brezillon@collabora.com>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Hans Verkuil <hans.verkuil@cisco.com>,
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Sakari Ailus <sakari.ailus@iki.fi>,
	linux-media@vger.kernel.org
Cc: Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	devicetree@vger.kernel.org, Tomasz Figa <tfiga@chromium.org>,
	Nicolas Dufresne <nicolas@ndufresne.ca>,
	kernel@collabora.com,
	Paul Kocialkowski <paul.kocialkowski@bootlin.com>,
	Ezequiel Garcia <ezequiel@collabora.com>,
	Jonas Karlman <jonas@kwiboo.se>,
	linux-rockchip@lists.infradead.org,
	Heiko Stuebner <heiko@sntech.de>
Subject: Re: [PATCH v3 6/7] media: rkvdec: Add the rkvdec driver
Date: Fri, 13 Dec 2019 15:21:05 +0100	[thread overview]
Message-ID: <036d3ecb-2307-4e8c-eaad-3c70c8cbda22@xs4all.nl> (raw)
In-Reply-To: <20191213125414.90725-7-boris.brezillon@collabora.com>

Hi Boris,

A few small comments:

On 12/13/19 1:54 PM, Boris Brezillon wrote:
> The rockchip vdec block is a stateless decoder that's able to decode
> H264, HEVC and VP9 content. This commit adds the core infrastructure
> and the H264 backend. Support for VP9 and HEVS will be added later on.
> 
> Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
> ---
> Changes in v3:
> * Move the driver to drivers/staging/media/rkvdec/
> * Fix copy&paste error in the Kconfig desc
> * Use REC709 color space when resetting the capture format
> * Prepare things to support VP9
> * Move H264 priv-table field definition out of rkvdec-regs.h
> * Clarify the provenance of the CABAC table
> * Ease RPS,PPS_FIELD() definition/manipulation
> * Take DPB field flags into account
> * Use the generic H264 helpers to build the reflists
> ---
>  drivers/staging/media/Kconfig              |    2 +
>  drivers/staging/media/Makefile             |    1 +
>  drivers/staging/media/rkvdec/Kconfig       |   15 +
>  drivers/staging/media/rkvdec/Makefile      |    3 +
>  drivers/staging/media/rkvdec/rkvdec-h264.c | 1154 ++++++++++++++++++++
>  drivers/staging/media/rkvdec/rkvdec-regs.h |  239 ++++
>  drivers/staging/media/rkvdec/rkvdec.c      | 1130 +++++++++++++++++++
>  drivers/staging/media/rkvdec/rkvdec.h      |  124 +++
>  8 files changed, 2668 insertions(+)
>  create mode 100644 drivers/staging/media/rkvdec/Kconfig
>  create mode 100644 drivers/staging/media/rkvdec/Makefile
>  create mode 100644 drivers/staging/media/rkvdec/rkvdec-h264.c
>  create mode 100644 drivers/staging/media/rkvdec/rkvdec-regs.h
>  create mode 100644 drivers/staging/media/rkvdec/rkvdec.c
>  create mode 100644 drivers/staging/media/rkvdec/rkvdec.h
> 

<snip>

> diff --git a/drivers/staging/media/rkvdec/rkvdec-h264.c b/drivers/staging/media/rkvdec/rkvdec-h264.c
> new file mode 100644
> index 000000000000..6de4bd39f286
> --- /dev/null
> +++ b/drivers/staging/media/rkvdec/rkvdec-h264.c

<snip>

> +/*
> + * dpb poc related registers table
> + */

Shouldn't the next two arrays be const?

> +static u32 poc_reg_tbl_top_field[16] = {
> +	RKVDEC_REG_H264_POC_REFER0(0),
> +	RKVDEC_REG_H264_POC_REFER0(2),
> +	RKVDEC_REG_H264_POC_REFER0(4),
> +	RKVDEC_REG_H264_POC_REFER0(6),
> +	RKVDEC_REG_H264_POC_REFER0(8),
> +	RKVDEC_REG_H264_POC_REFER0(10),
> +	RKVDEC_REG_H264_POC_REFER0(12),
> +	RKVDEC_REG_H264_POC_REFER0(14),
> +	RKVDEC_REG_H264_POC_REFER1(1),
> +	RKVDEC_REG_H264_POC_REFER1(3),
> +	RKVDEC_REG_H264_POC_REFER1(5),
> +	RKVDEC_REG_H264_POC_REFER1(7),
> +	RKVDEC_REG_H264_POC_REFER1(9),
> +	RKVDEC_REG_H264_POC_REFER1(11),
> +	RKVDEC_REG_H264_POC_REFER1(13),
> +	RKVDEC_REG_H264_POC_REFER2(0)
> +};
> +
> +static u32 poc_reg_tbl_bottom_field[16] = {
> +	RKVDEC_REG_H264_POC_REFER0(1),
> +	RKVDEC_REG_H264_POC_REFER0(3),
> +	RKVDEC_REG_H264_POC_REFER0(5),
> +	RKVDEC_REG_H264_POC_REFER0(7),
> +	RKVDEC_REG_H264_POC_REFER0(9),
> +	RKVDEC_REG_H264_POC_REFER0(11),
> +	RKVDEC_REG_H264_POC_REFER0(13),
> +	RKVDEC_REG_H264_POC_REFER1(0),
> +	RKVDEC_REG_H264_POC_REFER1(2),
> +	RKVDEC_REG_H264_POC_REFER1(4),
> +	RKVDEC_REG_H264_POC_REFER1(6),
> +	RKVDEC_REG_H264_POC_REFER1(8),
> +	RKVDEC_REG_H264_POC_REFER1(10),
> +	RKVDEC_REG_H264_POC_REFER1(12),
> +	RKVDEC_REG_H264_POC_REFER1(14),
> +	RKVDEC_REG_H264_POC_REFER2(1)
> +};

<snip>

> diff --git a/drivers/staging/media/rkvdec/rkvdec.c b/drivers/staging/media/rkvdec/rkvdec.c
> new file mode 100644
> index 000000000000..97698be9072e
> --- /dev/null
> +++ b/drivers/staging/media/rkvdec/rkvdec.c
> @@ -0,0 +1,1130 @@

<snip>

> +static int rkvdec_queue_setup(struct vb2_queue *vq, unsigned int *num_buffers,
> +			      unsigned int *num_planes, unsigned int sizes[],
> +			      struct device *alloc_devs[])
> +{
> +	struct rkvdec_ctx *ctx = vb2_get_drv_priv(vq);
> +	struct v4l2_pix_format_mplane *pixfmt;
> +	struct v4l2_format *f;
> +	unsigned int i;
> +
> +	if (V4L2_TYPE_IS_OUTPUT(vq->type))
> +		f = &ctx->coded_fmt;
> +	else
> +		f = &ctx->decoded_fmt;
> +
> +	if (*num_planes) {
> +		if (*num_planes != f->fmt.pix_mp.num_planes)
> +			return -EINVAL;
> +
> +		for (i = 0; i < f->fmt.pix_mp.num_planes; i++) {
> +			if (sizes[i] < f->fmt.pix_mp.plane_fmt[i].sizeimage)
> +				return -EINVAL;
> +		}

Shouldn't there be a 'return 0' here? In the CREATE_BUFS case all you do is check
if the given size is large enough, and if so then you are done.

> +	} else {
> +		*num_planes = f->fmt.pix_mp.num_planes;
> +		for (i = 0; i < f->fmt.pix_mp.num_planes; i++)
> +			sizes[i] = f->fmt.pix_mp.plane_fmt[i].sizeimage;
> +	}
> +
> +	if (V4L2_TYPE_IS_OUTPUT(vq->type))
> +		return 0;
> +
> +	pixfmt = &ctx->decoded_fmt.fmt.pix_mp;
> +	sizes[0] += 128 * DIV_ROUND_UP(pixfmt->width, 16) *
> +		    DIV_ROUND_UP(pixfmt->height, 16);
> +	return 0;
> +}

<snip>

Regards,

	Hans