From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C46C4C2BA2B for ; Sun, 12 Apr 2020 16:38:42 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 888E0206A1 for ; Sun, 12 Apr 2020 16:38:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 888E0206A1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=sigxcpu.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2207F6E044; Sun, 12 Apr 2020 16:38:42 +0000 (UTC) Received: from honk.sigxcpu.org (honk.sigxcpu.org [24.134.29.49]) by gabe.freedesktop.org (Postfix) with ESMTPS id 673AE89FA9 for ; Sun, 12 Apr 2020 16:38:40 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by honk.sigxcpu.org (Postfix) with ESMTP id 5DAB7FB03; Sun, 12 Apr 2020 18:38:38 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at honk.sigxcpu.org Received: from honk.sigxcpu.org ([127.0.0.1]) by localhost (honk.sigxcpu.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id KFNyfXJzYr2u; Sun, 12 Apr 2020 18:38:35 +0200 (CEST) Received: by bogon.sigxcpu.org (Postfix, from userid 1000) id 2FCF640601; Sun, 12 Apr 2020 18:38:35 +0200 (CEST) Date: Sun, 12 Apr 2020 18:38:35 +0200 From: Guido =?iso-8859-1?Q?G=FCnther?= To: Laurent Pinchart Subject: Re: [PATCH v11 1/2] dt-bindings: display/bridge: Add binding for NWL mipi dsi host controller Message-ID: <20200412163835.GB4007@bogon.m.sigxcpu.org> References: <147ffc1e4dee3a623e5dca25d84565d386a34112.1586427783.git.agx@sigxcpu.org> <20200410112342.GB4751@pendragon.ideasonboard.com> <20200410124516.GA27532@bogon.m.sigxcpu.org> <20200410125732.GE4751@pendragon.ideasonboard.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200410125732.GE4751@pendragon.ideasonboard.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , devicetree@vger.kernel.org, Jernej Skrabec , Pengutronix Kernel Team , Sam Ravnborg , Neil Armstrong , David Airlie , Sascha Hauer , Jonas Karlman , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Andrzej Hajda , Rob Herring , Arnd Bergmann , NXP Linux Team , Robert Chiras , Lee Jones , Shawn Guo , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Laurent, On Fri, Apr 10, 2020 at 03:57:32PM +0300, Laurent Pinchart wrote: > Hi Guido, > = > On Fri, Apr 10, 2020 at 02:45:16PM +0200, Guido G=FCnther wrote: > > On Fri, Apr 10, 2020 at 02:23:42PM +0300, Laurent Pinchart wrote: > > > On Thu, Apr 09, 2020 at 12:42:01PM +0200, Guido G=FCnther wrote: > > > > The Northwest Logic MIPI DSI IP core can be found in NXPs i.MX8 SoC= s. > > > > = > > > > Signed-off-by: Guido G=FCnther > > > > Tested-by: Robert Chiras > > > > Reviewed-by: Rob Herring > > > > Acked-by: Sam Ravnborg > > > > Reviewed-by: Fabio Estevam > > > > --- > > > > .../bindings/display/bridge/nwl-dsi.yaml | 226 ++++++++++++++= ++++ > > > > 1 file changed, 226 insertions(+) > > > > create mode 100644 Documentation/devicetree/bindings/display/bridg= e/nwl-dsi.yaml > > > > = > > > > diff --git a/Documentation/devicetree/bindings/display/bridge/nwl-d= si.yaml b/Documentation/devicetree/bindings/display/bridge/nwl-dsi.yaml > > > > new file mode 100644 > > > > index 000000000000..8aff2d68fc33 > > > > --- /dev/null > > > > +++ b/Documentation/devicetree/bindings/display/bridge/nwl-dsi.yaml > > > > @@ -0,0 +1,226 @@ > > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > > > +%YAML 1.2 > > > > +--- > > > > +$id: http://devicetree.org/schemas/display/bridge/nwl-dsi.yaml# > > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > > + > > > > +title: Northwest Logic MIPI-DSI controller on i.MX SoCs > > > > + > > > > +maintainers: > > > > + - Guido G=FAnther > > > > + - Robert Chiras > > > > + > > > > +description: | > > > > + NWL MIPI-DSI host controller found on i.MX8 platforms. This is a= dsi bridge for > > > > + the SOCs NWL MIPI-DSI host controller. > > > > + > > > > +properties: > > > > + compatible: > > > > + const: fsl,imx8mq-nwl-dsi > > > > + > > > > + reg: > > > > + maxItems: 1 > > > > + > > > > + interrupts: > > > > + maxItems: 1 > > > > + > > > > + '#address-cells': > > > > + const: 1 > > > > + > > > > + '#size-cells': > > > > + const: 0 > > > > + > > > > + clocks: > > > > + items: > > > > + - description: DSI core clock > > > > + - description: RX_ESC clock (used in escape mode) > > > > + - description: TX_ESC clock (used in escape mode) > > > > + - description: PHY_REF clock > > > > + - description: LCDIF clock > > > > + > > > > + clock-names: > > > > + items: > > > > + - const: core > > > > + - const: rx_esc > > > > + - const: tx_esc > > > > + - const: phy_ref > > > > + - const: lcdif > > > > + > > > > + mux-controls: > > > > + description: > > > > + mux controller node to use for operating the input mux > > > > + > > > > + phys: > > > > + maxItems: 1 > > > > + description: > > > > + A phandle to the phy module representing the DPHY > > > > + > > > > + phy-names: > > > > + items: > > > > + - const: dphy > > > > + > > > > + power-domains: > > > > + maxItems: 1 > > > > + > > > > + resets: > > > > + items: > > > > + - description: dsi byte reset line > > > > + - description: dsi dpi reset line > > > > + - description: dsi esc reset line > > > > + - description: dsi pclk reset line > > > > + > > > > + reset-names: > > > > + items: > > > > + - const: byte > > > > + - const: dpi > > > > + - const: esc > > > > + - const: pclk > > > > + > > > > + ports: > > > > + type: object > > > > + description: > > > > + A node containing DSI input & output port nodes with endpoint > > > > + definitions as documented in > > > > + Documentation/devicetree/bindings/graph.txt. > > > > + properties: > > > > + port@0: > > > > + type: object > > > > + description: > > > > + Input port node to receive pixel data from the > > > > + display controller. Exactly one endpoint must be > > > > + specified. > > > > + properties: > > > > + '#address-cells': > > > > + const: 1 > > > > + > > > > + '#size-cells': > > > > + const: 0 > > > > + > > > > + endpoint@0: > > > > + description: sub-node describing the input from LCDIF > > > > + type: object > > > > + > > > > + endpoint@1: > > > > + description: sub-node describing the input from DCSS > > > > + type: object > > > = > > > This models the two inputs to the IP core, that are connected to a mux > > > internally, controlled through mux-controls, right ? Why is a single > > > endpoint supported then, if there are two connections at the hardware > > > level, and why is this using endpoints instead of ports as there are > > > really two input ports ? > > = > > That came out of > > = > > https://lore.kernel.org/linux-arm-kernel/c86b7ca2-7799-eafd-c380-e4b551= 520837@samsung.com/ > > = > > # If the ip has separate lines for DCSS and LCDIF you should distinguish > > # by port number. If they are shared > > # you can use endpoint number to specify DCSS or LCDIF, in both cases > > # bindings should be adjusted. > > = > > I read that as > > = > > - distinguish by endpoint number: > > = > > eLCDIF--\ | > > ----| nwl > > DCSS----/ | > > = > > - distinguish by port number: > > = > > eLCDIF-------| > > | nwl > > DCSS --------| > = > I fully agree with you here, but in the first case I would expect the > mux to be outside of the NWL, while in the second case it would be > inside. If I understand the issue correctly, the mux is not part of the > NWL, right ? The endpoint model would then be good, but leaves the issue > Documentation/devicetree/bindings/media/video-mux.txt, but that would > require some support on the driver side. Do you think it would be a good > way forward ? Binding wise that looks like a good fit. I then thought about the implementation and figured we'd end up with something like a bridge that basically muxes inputs - or did you have something different in mind? That sounds generally useful when we e.g. look at runtime switching the input display controller. > The alternative is to consider the mux + NWL as one device (more or less > an i.MX8M-specific integration wrapper of the NWL), but in that case > there should be two ports I believe. I'd go with that for the moment and fold in the above at a later point if needed. I'm happy to work on that but would like to work on some parts of the imx8mq display stack first. Cheers, -- Guido > > From the imx8mq ref manual i didn't see separate input lines for DCSS vs > > eLCDIF the the NWL IP so i went with endpoints instead of ports. I'm > > happy to change that if i got it wrong. > > = > > > Apart from that the bindings look ok to me. > > > = > > > > + > > > > + reg: > > > > + const: 0 > > > > + > > > > + required: > > > > + - '#address-cells' > > > > + - '#size-cells' > > > > + - reg > > > > + > > > > + oneOf: > > > > + - required: > > > > + - endpoint@0 > > > > + - required: > > > > + - endpoint@1 > > > > + > > > > + additionalProperties: false > > > > + > > > > + port@1: > > > > + type: object > > > > + description: > > > > + DSI output port node to the panel or the next bridge > > > > + in the chain > > > > + > > > > + '#address-cells': > > > > + const: 1 > > > > + > > > > + '#size-cells': > > > > + const: 0 > > > > + > > > > + required: > > > > + - '#address-cells' > > > > + - '#size-cells' > > > > + - port@0 > > > > + - port@1 > > > > + > > > > + additionalProperties: false > > > > + > > > > +patternProperties: > > > > + "^panel@[0-9]+$": > > > > + type: object > > > > + > > > > +required: > > > > + - '#address-cells' > > > > + - '#size-cells' > > > > + - clock-names > > > > + - clocks > > > > + - compatible > > > > + - interrupts > > > > + - mux-controls > > > > + - phy-names > > > > + - phys > > > > + - ports > > > > + - reg > > > > + - reset-names > > > > + - resets > > > > + > > > > +additionalProperties: false > > > > + > > > > +examples: > > > > + - | > > > > + > > > > + #include > > > > + #include > > > > + #include > > > > + > > > > + mipi_dsi: mipi_dsi@30a00000 { > > > > + #address-cells =3D <1>; > > > > + #size-cells =3D <0>; > > > > + compatible =3D "fsl,imx8mq-nwl-dsi"; > > > > + reg =3D <0x30A00000 0x300>; > > > > + clocks =3D <&clk IMX8MQ_CLK_DSI_CORE>, > > > > + <&clk IMX8MQ_CLK_DSI_AHB>, > > > > + <&clk IMX8MQ_CLK_DSI_IPG_DIV>, > > > > + <&clk IMX8MQ_CLK_DSI_PHY_REF>, > > > > + <&clk IMX8MQ_CLK_LCDIF_PIXEL>; > > > > + clock-names =3D "core", "rx_esc", "tx_esc", "phy_ref= ", "lcdif"; > > > > + interrupts =3D ; > > > > + mux-controls =3D <&mux 0>; > > > > + power-domains =3D <&pgc_mipi>; > > > > + resets =3D <&src IMX8MQ_RESET_MIPI_DSI_RESET_BYTE_N>, > > > > + <&src IMX8MQ_RESET_MIPI_DSI_DPI_RESET_N>, > > > > + <&src IMX8MQ_RESET_MIPI_DSI_ESC_RESET_N>, > > > > + <&src IMX8MQ_RESET_MIPI_DSI_PCLK_RESET_N>; > > > > + reset-names =3D "byte", "dpi", "esc", "pclk"; > > > > + phys =3D <&dphy>; > > > > + phy-names =3D "dphy"; > > > > + > > > > + panel@0 { > > > > + #address-cells =3D <1>; > > > > + #size-cells =3D <0>; > > > > + compatible =3D "rocktech,jh057n00900"; > > > > + reg =3D <0>; > > > > + port@0 { > > > > + reg =3D <0>; > > > > + panel_in: endpoint { > > > > + remote-endpoint =3D <&mipi_ds= i_out>; > > > > + }; > > > > + }; > > > > + }; > > > > + > > > > + ports { > > > > + #address-cells =3D <1>; > > > > + #size-cells =3D <0>; > > > > + > > > > + port@0 { > > > > + #size-cells =3D <0>; > > > > + #address-cells =3D <1>; > > > > + reg =3D <0>; > > > > + mipi_dsi_in: endpoint@0 { > > > > + reg =3D <0>; > > > > + remote-endpoint =3D <&lcdi= f_mipi_dsi>; > > > > + }; > > > > + }; > > > > + port@1 { > > > > + reg =3D <1>; > > > > + mipi_dsi_out: endpoint { > > > > + remote-endpoint =3D <&pan= el_in>; > > > > + }; > > > > + }; > > > > + }; > > > > + }; > = > -- = > Regards, > = > Laurent Pinchart > = _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel