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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 97B92C531D0 for ; Sat, 25 Jul 2026 05:08:22 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B52E410F506; Sat, 25 Jul 2026 05:08:21 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="Hv00ONOU"; dkim-atps=neutral Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id E373310F506 for ; Sat, 25 Jul 2026 05:08:19 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 8B20A40622; Sat, 25 Jul 2026 05:08:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E72A21F000E9; Sat, 25 Jul 2026 05:08:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784956099; bh=GN6aqntHEPq5XDOXgFW8etw4HsuTNEBa3VPzvY5PKqU=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Hv00ONOULMkkAlpWMUxcUCoLfA508BVmyB1VpzWromTSYnMrnx+zDS95OZxuM7L0W MO8tuW58ZI5U/PWkC9ATIBTKBaW2AbhHH6MiShZhS0j8Hbilk1qWPZjtY0wiXqx76W HH1V2xQsNQ62Qd+UMw2tfC2rtA5O6C7KEuSNZAEZcm8pTmpMYkAyLjC62tYMRsIpkn MwFX2HeZjOg9u+sVyCNimyGq8GHJPskT3u59Lowa8q89eVOB4s1rT/bYl2M0UUCaCp mULbGyYEKvO7I6e954TJBDF6Jb52waBnNB8WfI9GLD33yk2cckpkrJJ6EO/U2hakG/ TKuY6r4/A7y9Q== From: sashiko-bot@kernel.org Subject: Re: [PATCH RESEND 14/17] riscv: dts: spacemit: k3: add display nodes To: "Cody Kang" Cc: robh@kernel.org, olteanv@gmail.com, linux-phy@lists.infradead.org, conor+dt@kernel.org, vkoul@kernel.org, dri-devel@lists.freedesktop.org, neil.armstrong@linaro.org, devicetree@vger.kernel.org In-Reply-To: <20260725-k3-display-v1-14-6de34d80e86c@gmail.com> References: <20260725-k3-display-v1-0-6de34d80e86c@gmail.com> <20260725-k3-display-v1-14-6de34d80e86c@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Sat, 25 Jul 2026 05:08:18 +0000 Message-Id: <20260725050818.E72A21F000E9@smtp.kernel.org> 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: , Reply-To: sashiko-reviews@lists.linux.dev Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Thank you for your contribution! Sashiko AI review found 2 potential issue(= s) to consider: - [High] The DP controller hardware is not initialized before the eDP panel= probe is triggered, causing synchronous AUX transfers to fail or hang. - [High] The custom EDID read function violates the I2C EEPROM protocol by = omitting the Middle-of-Transaction (MOT) bit, breaking EDID reads on sinks = that require a repeated START. -- --- Patch [14]: [PATCH RESEND 14/17] riscv: dts: spacemit: k3: add display = nodes --- commit 9b9ee39195ad90a76f056f9bddbdabb8377b67ec Author: Cody Kang riscv: dts: spacemit: k3: add display nodes Add the SoC-level display nodes: the two Saturn DPUs, the two DP/eDP controllers with their PHY children. > diff --git a/arch/riscv/boot/dts/spacemit/k3-display.dtsi b/arch/riscv/bo= ot/dts/spacemit/k3-display.dtsi > new file mode 100644 > index 0000000000000..4892ee6acda22 > --- /dev/null > +++ b/arch/riscv/boot/dts/spacemit/k3-display.dtsi > @@ -0,0 +1,156 @@ [ ... ] > +&soc { [ ... ] > + edp0: edp@cac84000 { > + compatible =3D "spacemit,k3-inno-dp"; [Severity: High] Does enabling this device node cause the eDP panel probe to fail? Looking at inno_dp_probe() in drivers/gpu/drm/spacemit/spacemit_inno_dp.c, = it populates the eDP panel device on the AUX bus: ret =3D devm_of_dp_aux_populate_bus(&dp->aux, spacemit_dp_edp_link_panel); The panel driver probes synchronously and attempts an AUX transfer to read = the EDID. However, the DP controller's hardware registers (including the AUX clock divider DP_AUX_CTRL_CLK_DIV and soft resets) are not initialized until late= r: spacemit_inno_dp.c:spacemit_dp_bind() { ... ret =3D spacemit_dp_dev_init(dp); ... } The uninitialized controller ignores the transfer or the AUX state machine does not start, causing an unavoidable timeout. > + reg =3D <0x0 0xcac84000 0x0 0x4000>; [ ... ] > + dp1: dp@cac88000 { > + compatible =3D "spacemit,k3-inno-dp"; [Severity: High] Will EDID reads fail for sinks connected to this node? When reading EDID, the driver splits the transaction into a write and a rea= d: spacemit_inno_dp.c:spacemit_dp_conn_get_edid_block() { ... ret =3D spacemit_dp_aux_i2c_write(dp, DDC_ADDR, &edid_offset, 1); ... } It calls spacemit_dp_aux_i2c_write() which hardcodes the request: spacemit_inno_dp.c:spacemit_dp_aux_i2c_write() { ... .request =3D DP_AUX_I2C_WRITE, ... } The missing MOT (Middle-of-Transaction) bit guarantees an I2C STOP condition after writing the offset address. This resets the internal address pointer = of many standard EEPROMs, causing the subsequent read to repeatedly fetch bloc= k 0 instead of the requested extension block. > + reg =3D <0x0 0xcac88000 0x0 0x4000>; --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260725-k3-display= -v1-0-6de34d80e86c@gmail.com?part=3D14