linux-media.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Stefan Wahren <stefan.wahren@i2se.com>
To: Maxime Ripard <maxime@cerno.tech>
Cc: Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>,
	dave.stevenson@raspberrypi.com, devicetree@vger.kernel.org,
	kernel-list@raspberrypi.com, laurent.pinchart@ideasonboard.com,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-media@vger.kernel.org,
	linux-rpi-kernel@lists.infradead.org, lukasz@jany.st,
	mchehab@kernel.org, naush@raspberrypi.com, robh@kernel.org,
	tomi.valkeinen@ideasonboard.com,
	bcm-kernel-feedback-list@broadcom.com,
	Florian Fainelli <f.fainelli@gmail.com>
Subject: Re: [PATCH v5 03/11] dt-bindings: media: Add bindings for bcm2835-unicam
Date: Sun, 13 Feb 2022 16:48:45 +0100	[thread overview]
Message-ID: <f58bf6a9-c63f-19ab-36c8-a9a7b9182859@i2se.com> (raw)
In-Reply-To: <20220208155027.891055-4-jeanmichel.hautbois@ideasonboard.com>

Hi Maxime,

as someone with a little more insight to the clocks, i like to know your
opinion about the bcm2835-unicam binding.

Am 08.02.22 um 16:50 schrieb Jean-Michel Hautbois:
> Introduce the dt-bindings documentation for bcm2835 CCP2/CSI2 Unicam
> camera interface.
>
> Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
> Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
>
> ---
> v4:
> - make MAINTAINERS its own patch
> - describe the reg and clocks correctly
> - use a vendor entry for the number of data lanes
> ---
>  .../bindings/media/brcm,bcm2835-unicam.yaml   | 117 ++++++++++++++++++
>  1 file changed, 117 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
>
> diff --git a/Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml b/Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> new file mode 100644
> index 000000000000..1938ace23b3d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> @@ -0,0 +1,117 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/media/brcm,bcm2835-unicam.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Broadcom BCM283x Camera Interface (Unicam)
> +
> +maintainers:
> +  - Raspberry Pi Kernel Maintenance <kernel-list@raspberrypi.com>
> +
> +description: |-
> +  The Unicam block on BCM283x SoCs is the receiver for either
> +  CSI-2 or CCP2 data from image sensors or similar devices.
> +
> +  The main platform using this SoC is the Raspberry Pi family of boards.  On
> +  the Pi the VideoCore firmware can also control this hardware block, and
> +  driving it from two different processors will cause issues.  To avoid this,
> +  the firmware checks the device tree configuration during boot. If it finds
> +  device tree nodes whose name starts with 'csi' then it will stop the firmware
> +  accessing the block, and it can then safely be used via the device tree
> +  binding.
> +
> +properties:
> +  compatible:
> +    const: brcm,bcm2835-unicam
> +
> +  reg:
> +    items:
> +      - description: Unicam block.
> +      - description: Clock Manager Image (CMI) block.
> +
> +  reg-names:
> +    items:
> +      - const: unicam
> +      - const: cmi
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  clocks:
> +    items:
> +      - description: Clock to drive the LP state machine of Unicam.
> +      - description: Clock for the VPU (core clock).
> +
> +  clock-names:
> +    items:
> +      - const: lp
> +      - const: vpu
> +

according to this patch [1], the unicam driver only needs the VPU clock
reference just to enforce a minimum of 250 MHz. The firmware clock
binding and its driver is specific to the bcm2711, but the Unicam IP
exists since bcm2835.

So do you think the clock part is correct or should be the VPU clock
optional?

Best regards

[1] -
https://github.com/raspberrypi/linux/commit/fc5b041b2e952dc84279dda978472a73a4b3891c



  parent reply	other threads:[~2022-02-13 15:49 UTC|newest]

Thread overview: 51+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-02-08 15:50 [PATCH v5 00/11] Add support for BCM2835 camera interface (unicam) Jean-Michel Hautbois
2022-02-08 15:50 ` [PATCH v5 01/11] media: v4l: Add V4L2-PIX-FMT-Y12P format Jean-Michel Hautbois
2022-02-08 15:50 ` [PATCH v5 02/11] media: v4l: Add V4L2-PIX-FMT-Y14P format Jean-Michel Hautbois
2022-02-08 15:50 ` [PATCH v5 03/11] dt-bindings: media: Add bindings for bcm2835-unicam Jean-Michel Hautbois
2022-02-09 18:56   ` Rob Herring
2022-02-13 15:48   ` Stefan Wahren [this message]
2022-02-14  9:39     ` Maxime Ripard
2022-02-14  9:54       ` Laurent Pinchart
2022-02-14 11:32         ` Stefan Wahren
2022-02-21  7:10           ` Laurent Pinchart
2022-02-21 10:03             ` Maxime Ripard
2022-02-21 12:45             ` Stefan Wahren
2022-02-21 12:52               ` Laurent Pinchart
2022-02-25  8:19   ` Sakari Ailus
2022-02-08 15:50 ` [PATCH v5 04/11] media: bcm2835-unicam: Add support for CCP2/CSI2 camera interface Jean-Michel Hautbois
2022-02-08 21:00   ` Stefan Wahren
2022-02-13 12:52     ` Laurent Pinchart
2022-02-13 11:17   ` Stefan Wahren
2022-02-13 12:49     ` Laurent Pinchart
2022-02-20 10:01   ` Stefan Wahren
2022-02-20 10:08     ` Laurent Pinchart
2022-02-21  9:55   ` Laurent Pinchart
2022-02-25  9:29   ` Sakari Ailus
2023-07-02 15:23     ` Laurent Pinchart
2023-07-02 18:18       ` Sakari Ailus
2023-07-02 21:45         ` Laurent Pinchart
2023-07-02 21:47           ` Laurent Pinchart
2023-07-02 21:56             ` Sakari Ailus
2023-07-02 22:01               ` Laurent Pinchart
2023-07-02 22:20                 ` Sakari Ailus
2023-07-02 22:28                   ` Laurent Pinchart
2023-07-02 22:33                     ` Sakari Ailus
2023-07-02 21:53           ` Sakari Ailus
2023-07-02 21:58             ` Laurent Pinchart
2022-02-08 15:50 ` [PATCH v5 05/11] media: MAINTAINERS: add bcm2835 unicam driver Jean-Michel Hautbois
2022-02-08 15:58   ` Laurent Pinchart
2022-02-08 15:50 ` [PATCH v5 06/11] ARM: dts: bcm2711: Add unicam CSI nodes Jean-Michel Hautbois
2022-02-13 10:35   ` Stefan Wahren
2022-02-13 13:51     ` Stefan Wahren
2022-02-08 15:50 ` [PATCH v5 07/11] media: imx219: Rename mbus codes array Jean-Michel Hautbois
2022-02-08 15:50 ` [PATCH v5 08/11] media: imx219: Switch from open to init_cfg Jean-Michel Hautbois
2022-02-08 16:02   ` Laurent Pinchart
2022-02-08 16:05     ` Laurent Pinchart
2022-02-08 15:50 ` [PATCH v5 09/11] media: imx219: Introduce the set_routing operation Jean-Michel Hautbois
2022-02-21  7:17   ` Laurent Pinchart
2022-02-08 15:50 ` [PATCH v5 10/11] media: imx219: use a local v4l2_subdev to simplify reading Jean-Michel Hautbois
2022-02-08 15:50 ` [PATCH v5 11/11] media: imx219: Add support for the V4L2 subdev active state Jean-Michel Hautbois
2022-02-21  7:25   ` Laurent Pinchart
2022-02-16 20:57 ` [PATCH v5 00/11] Add support for BCM2835 camera interface (unicam) Stefan Wahren
2022-02-20 14:30   ` Jean-Michel Hautbois
2022-02-26 17:18     ` Stefan Wahren

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=f58bf6a9-c63f-19ab-36c8-a9a7b9182859@i2se.com \
    --to=stefan.wahren@i2se.com \
    --cc=bcm-kernel-feedback-list@broadcom.com \
    --cc=dave.stevenson@raspberrypi.com \
    --cc=devicetree@vger.kernel.org \
    --cc=f.fainelli@gmail.com \
    --cc=jeanmichel.hautbois@ideasonboard.com \
    --cc=kernel-list@raspberrypi.com \
    --cc=laurent.pinchart@ideasonboard.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=linux-rpi-kernel@lists.infradead.org \
    --cc=lukasz@jany.st \
    --cc=maxime@cerno.tech \
    --cc=mchehab@kernel.org \
    --cc=naush@raspberrypi.com \
    --cc=robh@kernel.org \
    --cc=tomi.valkeinen@ideasonboard.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).