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_INVALID,DKIM_SIGNED, 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 EB921C18E5B for ; Wed, 11 Mar 2020 13:20:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C22BF24655 for ; Wed, 11 Mar 2020 13:20:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=crapouillou.net header.i=@crapouillou.net header.b="yGNmzbLo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729460AbgCKNUV (ORCPT ); Wed, 11 Mar 2020 09:20:21 -0400 Received: from outils.crapouillou.net ([89.234.176.41]:35792 "EHLO crapouillou.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729103AbgCKNUV (ORCPT ); Wed, 11 Mar 2020 09:20:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1583932818; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VBz3FZ3ocy9Q4rzBgIHqJzobg61gP/HChhqdayvs+kk=; b=yGNmzbLo0S1R24n1OGPsGlftaQ2Z9STV+IYFchtu/eOrKBQs99T+Sg0QfS0jjJiM7iPlvB fCXv+Kd2EdwpQ7DhAMRKSbOYjLnORPIaX8ySm/AoXTBk1KYarlZRCzenNsMs2lIS3yfGGO mUxsbYR1ib0OtfKdfzzID+aaqdyuqWM= Date: Wed, 11 Mar 2020 14:20:09 +0100 From: Paul Cercueil Subject: Re: [RFC v2 6/8] MIPS: DTS: jz4780: account for Synopsys HDMI driver and LCD controller To: "H. Nikolaus Schaller" Cc: Paul Boddie , David Airlie , Daniel Vetter , Rob Herring , Mark Rutland , Ralf Baechle , Paul Burton , Linus Walleij , Andi Kleen , Krzysztof Kozlowski , Geert Uytterhoeven , "Eric W. Biederman" , Miquel Raynal , "open list:DRM PANEL DRIVERS" , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Linux Kernel Mailing List , linux-mips@vger.kernel.org, "open list:GPIO SUBSYSTEM" , Discussions about the Letux Kernel , MIPS Creator CI20 Development Message-Id: <1583932809.3.0@crapouillou.net> In-Reply-To: References: <04b485165f38744816a0446e95150cafdeb716ee.1582913973.git.hns@goldelico.com> <1583177253.3.5@crapouillou.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Hi Nikolaus, Le mer., mars 11, 2020 at 13:43, H. Nikolaus Schaller=20 a =E9crit : > Hi Paul, >=20 >> Am 02.03.2020 um 20:27 schrieb Paul Cercueil : >>=20 >> Hi Nikolaus, >>=20 >>=20 >> Le ven., f=E9vr. 28, 2020 at 19:19, H. Nikolaus Schaller=20 >> a =E9crit : >>> From: Paul Boddie >>> A specialisation of the generic Synopsys HDMI driver is employed=20 >>> for JZ4780 >>> HDMI support. This requires a new driver, plus device tree and=20 >>> configuration >>> modifications. >>> Signed-off-by: Paul Boddie >>> Signed-off-by: H. Nikolaus Schaller >>> --- >>> arch/mips/boot/dts/ingenic/jz4780.dtsi | 32=20 >>> ++++++++++++++++++++++++++ >>> 1 file changed, 32 insertions(+) >>> diff --git a/arch/mips/boot/dts/ingenic/jz4780.dtsi=20 >>> b/arch/mips/boot/dts/ingenic/jz4780.dtsi >>> index f928329b034b..391d4e1efd35 100644 >>> --- a/arch/mips/boot/dts/ingenic/jz4780.dtsi >>> +++ b/arch/mips/boot/dts/ingenic/jz4780.dtsi >>> @@ -433,4 +433,36 @@ >>> status =3D "disabled"; >>> }; >>> + >>> + hdmi: hdmi@10180000 { >>> + compatible =3D "ingenic,jz4780-dw-hdmi"; >>> + reg =3D <0x10180000 0x8000>; >>> + reg-io-width =3D <4>; >>> + >>> + clocks =3D <&cgu JZ4780_CLK_HDMI>, <&cgu JZ4780_CLK_AHB0>; >>> + clock-names =3D "isfr" , "iahb"; >>> + >>> + assigned-clocks =3D <&cgu JZ4780_CLK_HDMI>; >>> + assigned-clock-rates =3D <27000000>; >>=20 >> I *think* this should go to the board file. >>=20 >>> + >>> + interrupt-parent =3D <&intc>; >>> + interrupts =3D <3>; >>> + >>> + /* ddc-i2c-bus =3D <&i2c4>; */ >>> + >>> + status =3D "disabled"; >>> + }; >>> + >>> + lcd: lcd@13050000 { >>=20 >> The node name should be 'lcd-controller'. >>=20 >>> + compatible =3D "ingenic,jz4740-lcd"; >>=20 >> The JZ4780's LCD controller is much newer than the JZ4740 one, so=20 >> even if it works with the "ingenic,jz4740-lcd" compatible string,=20 >> you want it as a fallback. >> So this should be: compatible =3D "ingenic,jz4780-lcd",=20 >> "ingenic,jz4740-lcd". >>=20 >> That means the YAML should be updated too. >=20 > I have started to look into jz4780 HDMI setup again. >=20 > Well, there is no driver compatible to "ingenic,jz4780-lcd" so far > and it is questionalbe if we need a different one. >=20 > I think we should rather make the driver also compatible > than adding a fallback to ingenic,jz4740-lcdto the DTS. >=20 > The reason why this is better even if both LCDC are almost > compatible is that the jz4780 allows for much bigger displays > and therefore should have its own jz_soc_info with 4k x 2k > as maximum. Sure, feel free to extend the driver. > Next I tried to find out if the LCDC are really compatible. >=20 > Well the jz4780 has two lcdc instances but they are separated > by the reg addr. Next, there are unique features (like picture in > picture with alpha blending) but those are probably disabled > if not programmed from reset state. This may become a reason > to separate or augment the driver for the jz4780 but at the > moment we can ignore that. Two LCDC instances -> two lcd-controller@... nodes. It's that simple. The other features you listed are outside the LCDC, so outside the=20 scope of this driver. > There are also subtly different bit definitions and register > widths (e.g. 24 bit in addition to 16/18 bit modes or more bits > for the sync position) but it looks as if the ingenic_drm > driver already handles this. >=20 > Then I tried to read back the registers. Strangely they > are all 0x00000000. So there is no programming of the > lcd-controller in our DT setup with HDMI at all! How did you read them? Do it from the regmap: should be "cat=20 /sys/kernel/debug/regmap/13050000.lcd-controller/registers" (not sure=20 about the path) > I also checked that ingenic_drm_probe() is called and > returns successfully 0. It also reports that a /dev/fb > has been created: >=20 > [ 7.908830] ingenic-drm 13050000.lcd-controller: fb0:=20 > ingenic-drmdrmf frame buffer device >=20 > But for example ingenic_drm_encoder_atomic_mode_set() is > never called which should write some registers of the LCDC. >=20 > I only did see some calls to ingenic_drm_encoder_atomic_check(). >=20 > This of course explains why we have no HDMI signals despite > proper HPD and a /dev/fb0. Because the LCDC is not being > programmed. It won't be called until the HDMI driver says that the cable is=20 plugged, and there's a client application (e.g. fbdev emulation)=20 running. So the problem is most likely within the HDMI driver. Cheers, -Paul > Any ideas / hints how to check or improve? >=20 > BR and thanks, > Nikolaus >=20 = 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=-4.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,RDNS_NONE,SIGNED_OFF_BY,SPF_HELO_PASS,SPF_NONE,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from outils.crapouillou.net ([89.234.176.41]:35792 "EHLO crapouillou.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729103AbgCKNUV (ORCPT ); Wed, 11 Mar 2020 09:20:21 -0400 Date: Wed, 11 Mar 2020 14:20:09 +0100 From: Paul Cercueil Subject: Re: [RFC v2 6/8] MIPS: DTS: jz4780: account for Synopsys HDMI driver and LCD controller To: "H. Nikolaus Schaller" Cc: Paul Boddie , David Airlie , Daniel Vetter , Rob Herring , Mark Rutland , Ralf Baechle , Paul Burton , Linus Walleij , Andi Kleen , Krzysztof Kozlowski , Geert Uytterhoeven , "Eric W. Biederman" , Miquel Raynal , "open list:DRM PANEL DRIVERS" , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Linux Kernel Mailing List , linux-mips@vger.kernel.org, "open list:GPIO SUBSYSTEM" , Discussions about the Letux Kernel , MIPS Creator CI20 Development Message-Id: <1583932809.3.0@crapouillou.net> In-Reply-To: References: <04b485165f38744816a0446e95150cafdeb716ee.1582913973.git.hns@goldelico.com> <1583177253.3.5@crapouillou.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org List-ID: Message-ID: <20200311132009.U1qsbSkhH79hf5LO0loqRS_UR6ZOuFwNgNjMoEBQbmU@z> Hi Nikolaus, Le mer., mars 11, 2020 at 13:43, H. Nikolaus Schaller=20 a =E9crit : > Hi Paul, >=20 >> Am 02.03.2020 um 20:27 schrieb Paul Cercueil : >>=20 >> Hi Nikolaus, >>=20 >>=20 >> Le ven., f=E9vr. 28, 2020 at 19:19, H. Nikolaus Schaller=20 >> a =E9crit : >>> From: Paul Boddie >>> A specialisation of the generic Synopsys HDMI driver is employed=20 >>> for JZ4780 >>> HDMI support. This requires a new driver, plus device tree and=20 >>> configuration >>> modifications. >>> Signed-off-by: Paul Boddie >>> Signed-off-by: H. Nikolaus Schaller >>> --- >>> arch/mips/boot/dts/ingenic/jz4780.dtsi | 32=20 >>> ++++++++++++++++++++++++++ >>> 1 file changed, 32 insertions(+) >>> diff --git a/arch/mips/boot/dts/ingenic/jz4780.dtsi=20 >>> b/arch/mips/boot/dts/ingenic/jz4780.dtsi >>> index f928329b034b..391d4e1efd35 100644 >>> --- a/arch/mips/boot/dts/ingenic/jz4780.dtsi >>> +++ b/arch/mips/boot/dts/ingenic/jz4780.dtsi >>> @@ -433,4 +433,36 @@ >>> status =3D "disabled"; >>> }; >>> + >>> + hdmi: hdmi@10180000 { >>> + compatible =3D "ingenic,jz4780-dw-hdmi"; >>> + reg =3D <0x10180000 0x8000>; >>> + reg-io-width =3D <4>; >>> + >>> + clocks =3D <&cgu JZ4780_CLK_HDMI>, <&cgu JZ4780_CLK_AHB0>; >>> + clock-names =3D "isfr" , "iahb"; >>> + >>> + assigned-clocks =3D <&cgu JZ4780_CLK_HDMI>; >>> + assigned-clock-rates =3D <27000000>; >>=20 >> I *think* this should go to the board file. >>=20 >>> + >>> + interrupt-parent =3D <&intc>; >>> + interrupts =3D <3>; >>> + >>> + /* ddc-i2c-bus =3D <&i2c4>; */ >>> + >>> + status =3D "disabled"; >>> + }; >>> + >>> + lcd: lcd@13050000 { >>=20 >> The node name should be 'lcd-controller'. >>=20 >>> + compatible =3D "ingenic,jz4740-lcd"; >>=20 >> The JZ4780's LCD controller is much newer than the JZ4740 one, so=20 >> even if it works with the "ingenic,jz4740-lcd" compatible string,=20 >> you want it as a fallback. >> So this should be: compatible =3D "ingenic,jz4780-lcd",=20 >> "ingenic,jz4740-lcd". >>=20 >> That means the YAML should be updated too. >=20 > I have started to look into jz4780 HDMI setup again. >=20 > Well, there is no driver compatible to "ingenic,jz4780-lcd" so far > and it is questionalbe if we need a different one. >=20 > I think we should rather make the driver also compatible > than adding a fallback to ingenic,jz4740-lcdto the DTS. >=20 > The reason why this is better even if both LCDC are almost > compatible is that the jz4780 allows for much bigger displays > and therefore should have its own jz_soc_info with 4k x 2k > as maximum. Sure, feel free to extend the driver. > Next I tried to find out if the LCDC are really compatible. >=20 > Well the jz4780 has two lcdc instances but they are separated > by the reg addr. Next, there are unique features (like picture in > picture with alpha blending) but those are probably disabled > if not programmed from reset state. This may become a reason > to separate or augment the driver for the jz4780 but at the > moment we can ignore that. Two LCDC instances -> two lcd-controller@... nodes. It's that simple. The other features you listed are outside the LCDC, so outside the=20 scope of this driver. > There are also subtly different bit definitions and register > widths (e.g. 24 bit in addition to 16/18 bit modes or more bits > for the sync position) but it looks as if the ingenic_drm > driver already handles this. >=20 > Then I tried to read back the registers. Strangely they > are all 0x00000000. So there is no programming of the > lcd-controller in our DT setup with HDMI at all! How did you read them? Do it from the regmap: should be "cat=20 /sys/kernel/debug/regmap/13050000.lcd-controller/registers" (not sure=20 about the path) > I also checked that ingenic_drm_probe() is called and > returns successfully 0. It also reports that a /dev/fb > has been created: >=20 > [ 7.908830] ingenic-drm 13050000.lcd-controller: fb0:=20 > ingenic-drmdrmf frame buffer device >=20 > But for example ingenic_drm_encoder_atomic_mode_set() is > never called which should write some registers of the LCDC. >=20 > I only did see some calls to ingenic_drm_encoder_atomic_check(). >=20 > This of course explains why we have no HDMI signals despite > proper HPD and a /dev/fb0. Because the LCDC is not being > programmed. It won't be called until the HDMI driver says that the cable is=20 plugged, and there's a client application (e.g. fbdev emulation)=20 running. So the problem is most likely within the HDMI driver. Cheers, -Paul > Any ideas / hints how to check or improve? >=20 > BR and thanks, > Nikolaus >=20 = 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_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 D52D4C1975A for ; Thu, 12 Mar 2020 08:08:33 +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 AD33D20650 for ; Thu, 12 Mar 2020 08:08:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=crapouillou.net header.i=@crapouillou.net header.b="yGNmzbLo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AD33D20650 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=crapouillou.net 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 1583A6EA3F; Thu, 12 Mar 2020 08:08:15 +0000 (UTC) Received: from crapouillou.net (outils.crapouillou.net [89.234.176.41]) by gabe.freedesktop.org (Postfix) with ESMTPS id DA60489E35 for ; Wed, 11 Mar 2020 13:20:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1583932818; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VBz3FZ3ocy9Q4rzBgIHqJzobg61gP/HChhqdayvs+kk=; b=yGNmzbLo0S1R24n1OGPsGlftaQ2Z9STV+IYFchtu/eOrKBQs99T+Sg0QfS0jjJiM7iPlvB fCXv+Kd2EdwpQ7DhAMRKSbOYjLnORPIaX8ySm/AoXTBk1KYarlZRCzenNsMs2lIS3yfGGO mUxsbYR1ib0OtfKdfzzID+aaqdyuqWM= Date: Wed, 11 Mar 2020 14:20:09 +0100 From: Paul Cercueil Subject: Re: [RFC v2 6/8] MIPS: DTS: jz4780: account for Synopsys HDMI driver and LCD controller To: "H. Nikolaus Schaller" Message-Id: <1583932809.3.0@crapouillou.net> In-Reply-To: References: <04b485165f38744816a0446e95150cafdeb716ee.1582913973.git.hns@goldelico.com> <1583177253.3.5@crapouillou.net> MIME-Version: 1.0 X-Mailman-Approved-At: Thu, 12 Mar 2020 08:08:13 +0000 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 , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Paul Boddie , Geert Uytterhoeven , Paul Burton , "open list:GPIO SUBSYSTEM" , David Airlie , MIPS Creator CI20 Development , "open list:DRM PANEL DRIVERS" , Linux Kernel Mailing List , Ralf Baechle , linux-mips@vger.kernel.org, Andi Kleen , Rob Herring , Krzysztof Kozlowski , Miquel Raynal , Discussions about the Letux Kernel , "Eric W. Biederman" Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1"; Format="flowed" Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Nikolaus, Le mer., mars 11, 2020 at 13:43, H. Nikolaus Schaller = a =E9crit : > Hi Paul, > = >> Am 02.03.2020 um 20:27 schrieb Paul Cercueil : >> = >> Hi Nikolaus, >> = >> = >> Le ven., f=E9vr. 28, 2020 at 19:19, H. Nikolaus Schaller = >> a =E9crit : >>> From: Paul Boddie >>> A specialisation of the generic Synopsys HDMI driver is employed = >>> for JZ4780 >>> HDMI support. This requires a new driver, plus device tree and = >>> configuration >>> modifications. >>> Signed-off-by: Paul Boddie >>> Signed-off-by: H. Nikolaus Schaller >>> --- >>> arch/mips/boot/dts/ingenic/jz4780.dtsi | 32 = >>> ++++++++++++++++++++++++++ >>> 1 file changed, 32 insertions(+) >>> diff --git a/arch/mips/boot/dts/ingenic/jz4780.dtsi = >>> b/arch/mips/boot/dts/ingenic/jz4780.dtsi >>> index f928329b034b..391d4e1efd35 100644 >>> --- a/arch/mips/boot/dts/ingenic/jz4780.dtsi >>> +++ b/arch/mips/boot/dts/ingenic/jz4780.dtsi >>> @@ -433,4 +433,36 @@ >>> status =3D "disabled"; >>> }; >>> + >>> + hdmi: hdmi@10180000 { >>> + compatible =3D "ingenic,jz4780-dw-hdmi"; >>> + reg =3D <0x10180000 0x8000>; >>> + reg-io-width =3D <4>; >>> + >>> + clocks =3D <&cgu JZ4780_CLK_HDMI>, <&cgu JZ4780_CLK_AHB0>; >>> + clock-names =3D "isfr" , "iahb"; >>> + >>> + assigned-clocks =3D <&cgu JZ4780_CLK_HDMI>; >>> + assigned-clock-rates =3D <27000000>; >> = >> I *think* this should go to the board file. >> = >>> + >>> + interrupt-parent =3D <&intc>; >>> + interrupts =3D <3>; >>> + >>> + /* ddc-i2c-bus =3D <&i2c4>; */ >>> + >>> + status =3D "disabled"; >>> + }; >>> + >>> + lcd: lcd@13050000 { >> = >> The node name should be 'lcd-controller'. >> = >>> + compatible =3D "ingenic,jz4740-lcd"; >> = >> The JZ4780's LCD controller is much newer than the JZ4740 one, so = >> even if it works with the "ingenic,jz4740-lcd" compatible string, = >> you want it as a fallback. >> So this should be: compatible =3D "ingenic,jz4780-lcd", = >> "ingenic,jz4740-lcd". >> = >> That means the YAML should be updated too. > = > I have started to look into jz4780 HDMI setup again. > = > Well, there is no driver compatible to "ingenic,jz4780-lcd" so far > and it is questionalbe if we need a different one. > = > I think we should rather make the driver also compatible > than adding a fallback to ingenic,jz4740-lcdto the DTS. > = > The reason why this is better even if both LCDC are almost > compatible is that the jz4780 allows for much bigger displays > and therefore should have its own jz_soc_info with 4k x 2k > as maximum. Sure, feel free to extend the driver. > Next I tried to find out if the LCDC are really compatible. > = > Well the jz4780 has two lcdc instances but they are separated > by the reg addr. Next, there are unique features (like picture in > picture with alpha blending) but those are probably disabled > if not programmed from reset state. This may become a reason > to separate or augment the driver for the jz4780 but at the > moment we can ignore that. Two LCDC instances -> two lcd-controller@... nodes. It's that simple. The other features you listed are outside the LCDC, so outside the = scope of this driver. > There are also subtly different bit definitions and register > widths (e.g. 24 bit in addition to 16/18 bit modes or more bits > for the sync position) but it looks as if the ingenic_drm > driver already handles this. > = > Then I tried to read back the registers. Strangely they > are all 0x00000000. So there is no programming of the > lcd-controller in our DT setup with HDMI at all! How did you read them? Do it from the regmap: should be "cat = /sys/kernel/debug/regmap/13050000.lcd-controller/registers" (not sure = about the path) > I also checked that ingenic_drm_probe() is called and > returns successfully 0. It also reports that a /dev/fb > has been created: > = > [ 7.908830] ingenic-drm 13050000.lcd-controller: fb0: = > ingenic-drmdrmf frame buffer device > = > But for example ingenic_drm_encoder_atomic_mode_set() is > never called which should write some registers of the LCDC. > = > I only did see some calls to ingenic_drm_encoder_atomic_check(). > = > This of course explains why we have no HDMI signals despite > proper HPD and a /dev/fb0. Because the LCDC is not being > programmed. It won't be called until the HDMI driver says that the cable is = plugged, and there's a client application (e.g. fbdev emulation) = running. So the problem is most likely within the HDMI driver. Cheers, -Paul > Any ideas / hints how to check or improve? > = > BR and thanks, > Nikolaus > = _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel