RE: [PATCH v7 4/9] media: chips-media: wave6: Add v4l2 m2m driver support

Hi, Frank.

-----Original Message-----
From: Frank Li <redacted>
Sent: Friday, September 11, 2026 5:37 AM
To: Nas Chung <nas.chung@chipsnmedia.com>
Cc: mchehab@kernel.org; hverkuil@xs4all.nl; robh@kernel.org;
krzk+dt@kernel.org; conor+dt@kernel.org; shawnguo@kernel.org;
s.hauer@pengutronix.de; linux-media@vger.kernel.org;
devicetree@vger.kernel.org; linux-kernel@vger.kernel.org; linux-imx@nxp.com;
linux-arm-kernel@lists.infradead.org; jackson.lee
[off-list ref]; lafley.kim [off-list ref];
marek.vasut@mailbox.org; Ming Qian [off-list ref]
Subject: Re: [PATCH v7 4/9] media: chips-media: wave6: Add v4l2 m2m driver
support

On Fri, Sep 04, 2026 at 03:46:30PM +0900, Nas Chung wrote:

quoted

Add v4l2 m2m stateful driver support for the
Chips&Media Wave6 video codec IP, including both encoder and decoder.

The following features and formats are supported:
Encoder (8bit only):
- Supported codecs: AVC, HEVC
- Supported input formats:
  * V4L2_PIX_FMT_YUV420/NV12/NV21
  * V4L2_PIX_FMT_YUV422P/NV16/NV61
  * V4L2_PIX_FMT_YUYV
  * V4L2_PIX_FMT_YUV24/NV24/NV42
  * V4L2_PIX_FMT_RGB24
  * V4L2_PIX_FMT_P010
  * V4L2_PIX_FMT_ARGB32
  * V4L2_PIX_FMT_RGBA32
  * V4L2_PIX_FMT_XRGB32
  * V4L2_PIX_FMT_ARGB2101010
- Supports multiplanar format
- Although 10-bit input formats are supported (e.g., P010, ARGB2101010),
  encoded output is limited to 8-bit streams
- Supports crop
- Supports extensive v4l2 encoder control

Decoder (8bit only):
- Supported codecs: AVC, HEVC (8bit only)
- Supported output formats: V4L2_PIX_FMT_YUV420/NV12/NV21
- Supports multiplanar format
- Supports scale down
- Supports dynamic resolution change

Note: While other versions of the Wave6 IP may support VP9 decoding and
AV1 decoding and encoding those formats are not implemented or validated
in this driver at this time.

Signed-off-by: Nas Chung <nas.chung@chipsnmedia.com>
Tested-by: Ming Qian <redacted>
Tested-by: Marek Vasut <redacted>
---

...

quoted

+
+u64 wave6_vpu_cycle_to_ns(struct vpu_core_device *core, u64 cycle)
+{
+	unsigned long rate;
+
+	if (!core->num_clks || !core->clks)
+		return 0;
+
+	rate = clk_get_rate(core->clks[0].clk);
+	if (!rate)
+		return 0;
+
+	return (cycle * NSEC_PER_SEC) / rate;

div_u64, otherwise 32bit compiler build failure.

I'll fix this in v8.

Thanks.
Nas.

Frank

quoted

+}
+
+int wave6_vpu_wait_interrupt(struct vpu_instance *inst, unsigned int

timeout)

quoted

+{
+	int ret;
+
+	ret = wait_for_completion_timeout(&inst->irq_done,
+					  msecs_to_jiffies(timeout));
+	if (!ret)
+		return -ETIMEDOUT;
+
+	reinit_completion(&inst->irq_done);
+
+	return 0;
+}
+