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=-6.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 E3F59C43603 for ; Sun, 8 Dec 2019 21:24:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A3DA12053B for ; Sun, 8 Dec 2019 21:24:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="gCVJyDsj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726626AbfLHVYM (ORCPT ); Sun, 8 Dec 2019 16:24:12 -0500 Received: from mail-ed1-f68.google.com ([209.85.208.68]:33580 "EHLO mail-ed1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726555AbfLHVYL (ORCPT ); Sun, 8 Dec 2019 16:24:11 -0500 Received: by mail-ed1-f68.google.com with SMTP id r21so274486edq.0; Sun, 08 Dec 2019 13:24:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=1nk/gKZH1FhHqU9Pe1PbIuJjILmu3krdS2vmCgQ6yeE=; b=gCVJyDsjFA5BSxxGpDHN7BBuKg262JZYpJLAB4/sc1vsqnU3VGKRKlnVk+4QvmlnFr fXoEx7IpAdg2JzzrCyMgZ0fyD/S7p7fc6oS3mfVafsUE/cwbXxkqnPoiv9hphR89TBBM vcmo/6Q0dGS0mN4o6ykQdilIbLfw7jja+EepFumijs7QHoto5a5fHn4TYkRaOHpBEWpK 64xTC5cRyXMOUb0Kns/rXefwH8IwoUWGPtQ/+D0y+CLSMcDvVTBaFx5hkdDDgX3dmw4y YuqcTZ5KIWj3VtxLeLMTccXJWeck2iDarqeE/wFpomB0fmGNnbAUDZpinsRamqgM0CVC q9Qw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=1nk/gKZH1FhHqU9Pe1PbIuJjILmu3krdS2vmCgQ6yeE=; b=PDKOJWNCy/3gQrEhVl+RpleUBT16Q0U04wOyfpYTKa/9Qusf2iuJLc5dKzeJJZFnOs T11O70K2FcHCZzcMlDvI7oibEMkevaFMrq58ry4hRN+AnsdUu0AbaXKqCOiiE/Ym0V+K 1RLatdzIPmPfkLut5E0FUlwWx6AcnFf5xKCaXFnzgfdyKyzI1ivjKHFL7NT840UJjvjy JnUUL27ILBSNp6V4mOTppC5xxYi66qP2jrWvmITAyu+JH0+ROPL5CiVHRBiSXWBUGBv7 N0j0AUiM3W9P3LIpNIB1b3Hp1qwxr+HivD4xJHbRAJ7Up+K3N4jESCgWsj0cFALRGxyS SbCg== X-Gm-Message-State: APjAAAX1xnNYCdOO3SkZYIduMs+VR7MocCyORDhWldalkdEOP64eJJOw R3nQs4j18l1P88wReqP/c6Y+f644mfpscS80rqQ= X-Google-Smtp-Source: APXvYqx73kfdWPrboFUtNODQvA4oqUZOQKE8IoT7QOlBvCEPaDkEwplbpUrC4KMgS7+Jwpf5kzfyBL4PWdanxlxzHxs= X-Received: by 2002:aa7:c49a:: with SMTP id m26mr29049116edq.264.1575840249055; Sun, 08 Dec 2019 13:24:09 -0800 (PST) MIME-Version: 1.0 References: <20191207203553.286017-1-robdclark@gmail.com> <20191207203553.286017-2-robdclark@gmail.com> <20191208144533.GA14311@pendragon.ideasonboard.com> <20191208182757.GE14311@pendragon.ideasonboard.com> In-Reply-To: <20191208182757.GE14311@pendragon.ideasonboard.com> From: Rob Clark Date: Sun, 8 Dec 2019 13:23:59 -0800 Message-ID: Subject: Re: [PATCH 1/4] dt-bindings: display: panel: document panel-id To: Laurent Pinchart Cc: dri-devel , linux-arm-msm , aarch64-laptops@lists.linaro.org, Vasily Khoruzhick , Bjorn Andersson , Jeffrey Hugo , Rob Clark , Thierry Reding , Sam Ravnborg , David Airlie , Daniel Vetter , Rob Herring , Mark Rutland , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , open list Content-Type: text/plain; charset="UTF-8" Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Sun, Dec 8, 2019 at 10:28 AM Laurent Pinchart wrote: > > Hi Rob, > > On Sun, Dec 08, 2019 at 08:50:32AM -0800, Rob Clark wrote: > > On Sun, Dec 8, 2019 at 6:45 AM Laurent Pinchart wrote: > > > On Sat, Dec 07, 2019 at 12:35:50PM -0800, Rob Clark wrote: > > > > From: Rob Clark > > > > > > > > For devices that have one of several possible panels installed, the > > > > panel-id property gives firmware a generic way to locate and enable the > > > > panel node corresponding to the installed panel. Example of how to use > > > > this property: > > > > > > > > ivo_panel { > > > > compatible = "ivo,m133nwf4-r0"; > > > > panel-id = <0xc5>; > > > > status = "disabled"; > > > > > > > > ports { > > > > port { > > > > ivo_panel_in_edp: endpoint { > > > > remote-endpoint = <&sn65dsi86_out_ivo>; > > > > }; > > > > }; > > > > }; > > > > }; > > > > > > > > boe_panel { > > > > compatible = "boe,nv133fhm-n61"; > > > > panel-id = <0xc4>; > > > > status = "disabled"; > > > > > > > > ports { > > > > port { > > > > boe_panel_in_edp: endpoint { > > > > remote-endpoint = <&sn65dsi86_out_boe>; > > > > }; > > > > }; > > > > }; > > > > }; > > > > > > > > sn65dsi86: bridge@2c { > > > > compatible = "ti,sn65dsi86"; > > > > > > > > ports { > > > > #address-cells = <1>; > > > > #size-cells = <0>; > > > > > > > > port@0 { > > > > reg = <0>; > > > > sn65dsi86_in_a: endpoint { > > > > remote-endpoint = <&dsi0_out>; > > > > }; > > > > }; > > > > > > > > port@1 { > > > > reg = <1>; > > > > > > > > sn65dsi86_out_boe: endpoint@c4 { > > > > remote-endpoint = <&boe_panel_in_edp>; > > > > }; > > > > > > > > sn65dsi86_out_ivo: endpoint@c5 { > > > > remote-endpoint = <&ivo_panel_in_edp>; > > > > }; > > > > }; > > > > }; > > > > }; > > > > > > > > Signed-off-by: Rob Clark > > > > --- > > > > .../bindings/display/panel/panel-common.yaml | 26 +++++++++++++++++++ > > > > 1 file changed, 26 insertions(+) > > > > > > > > diff --git a/Documentation/devicetree/bindings/display/panel/panel-common.yaml b/Documentation/devicetree/bindings/display/panel/panel-common.yaml > > > > index ef8d8cdfcede..6113319b91dd 100644 > > > > --- a/Documentation/devicetree/bindings/display/panel/panel-common.yaml > > > > +++ b/Documentation/devicetree/bindings/display/panel/panel-common.yaml > > > > @@ -75,6 +75,32 @@ properties: > > > > in the device graph bindings defined in > > > > Documentation/devicetree/bindings/graph.txt. > > > > > > > > + panel-id: > > > > + description: > > > > + To support the case where one of several different panels can be installed > > > > + on a device, the panel-id property can be used by the firmware to identify > > > > + which panel should have it's status changed to "ok". This property is not > > > > + used by the HLOS itself. > > > > > > If your firmware can modify the status property of a panel, it can also > > > add DT nodes. As discussed before, I don't think this belongs to DT. > > > Even if panel-id isn't used by the operating system, you have Linux > > > kernel patches in this series that show that this isn't transparent. > > > > I've already explained several times why this is not feasible. It > > would require DtbLoader to be familiar with each individual device, > > and be rev'd every time a new device appears. That is not practical > > at all. > > > > (And fwiw, the ACPI tables describe each panel.. with an ACPI method > > that is passed the the panel-id and returns the appropriate table.. > > since DT doesn't have methods, this is the solution.) > > > > I stand by this patch, we can't keep running away from this problem > > and wave the magic firmware wand. > > I believe in firmware solutions more than firmware magic wands :-) > and with that in mind, I think I've come up with a firmware solution, in the form of dtb overlays :-) I've managed to get DtbLoader to find and load a panel overlay based on the panel-id it reads, which drops all patches in the patchset except the last one, which now has this delta: --------- diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile index 6498a1ec893f..1a61e8da2521 100644 --- a/arch/arm64/boot/dts/qcom/Makefile +++ b/arch/arm64/boot/dts/qcom/Makefile @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 +subdir-y += panels dtb-$(CONFIG_ARCH_QCOM) += apq8016-sbc.dtb dtb-$(CONFIG_ARCH_QCOM) += apq8096-db820c.dtb dtb-$(CONFIG_ARCH_QCOM) += ipq8074-hk01.dtb diff --git a/arch/arm64/boot/dts/qcom/panels/Makefile b/arch/arm64/boot/dts/qcom/panels/Makefile new file mode 100644 index 000000000000..dbf55f423555 --- /dev/null +++ b/arch/arm64/boot/dts/qcom/panels/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0 +dtb-$(CONFIG_ARCH_QCOM) += panel-c4.dtb +dtb-$(CONFIG_ARCH_QCOM) += panel-c5.dtb diff --git a/arch/arm64/boot/dts/qcom/panels/panel-c4.dts b/arch/arm64/boot/dts/qcom/panels/panel-c4.dts new file mode 100644 index 000000000000..ebcf65419dad --- /dev/null +++ b/arch/arm64/boot/dts/qcom/panels/panel-c4.dts @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: BSD-3-Clause +/* + * Panel overlay for panel-id 0xc4 + * + * Copyright (c) 2019, Linaro Ltd. + */ + +/dts-v1/; +/plugin/; +/ { + fragment@0 { + target-path = "/panel"; + __overlay__ { + compatible = "boe,nv133fhm-n61"; + }; + }; +}; diff --git a/arch/arm64/boot/dts/qcom/panels/panel-c5.dts b/arch/arm64/boot/dts/qcom/panels/panel-c5.dts new file mode 100644 index 000000000000..0ad5bb6003e3 --- /dev/null +++ b/arch/arm64/boot/dts/qcom/panels/panel-c5.dts @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: BSD-3-Clause +/* + * Panel overlay for panel-id 0xc5 + * + * Copyright (c) 2019, Linaro Ltd. + */ + +/dts-v1/; +/plugin/; +/ { + fragment@0 { + target-path = "/panel"; + __overlay__ { + compatible = "ivo,m133nwf4-r0"; + }; + }; +}; diff --git a/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts b/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts index c35d8099d8eb..92c76afb721c 100644 --- a/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts +++ b/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts @@ -22,11 +22,13 @@ hsuart0 = &uart6; }; + /* + * stub node which defines how panel is connected to bridge, which + * will be updated by panel specific overlay + */ panel { - compatible = "ivo,m133nwf4-r0"; power-supply = <&vlcm_3v3>; no-hpd; - ports { port { panel_in_edp: endpoint { --------- Side note, try as I might, I couldn't get the 'target = <&phandle>' approach to work in the overlays, so I ended up going with target-path instead. From digging thru the fdt_overlay code, I *think* it is because I end up w/ an overlay dtb without symbols. In the end, I guess target-path works just as well. BR, -R