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 A8731C43458 for ; Wed, 1 Jul 2026 14:09:18 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EC6BA10E3A8; Wed, 1 Jul 2026 14:09:17 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="YkmBQd2N"; 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 6987D10E0F7 for ; Wed, 1 Jul 2026 14:09:16 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 28C5543ECB; Wed, 1 Jul 2026 14:09:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D151E1F000E9; Wed, 1 Jul 2026 14:09:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782914956; bh=4sod2++HE5GNde89J9Vk/9nGUJpRaReQ/yFbSXrvJ+E=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=YkmBQd2N1wfHLMAseikNwMrPyg7KVWWZIPWldCFuaMyFFeGc8tb8J/iy9ugxEhhrh +4cF3mP/k6xyG/+0iYugHF+JiKTG8Cc9Qp6FbdrhzDrEgoLnHyDNvAtnMKdHE4fhsI 3/TXZtlVWL8Jc0ly8MDguyLvhzncq7i/RQenHkkXDvLU3eB9PRYPx17gFVSGnKQV1d 0n+UAo5bcfAY2r/FtRFPMWnqVtTxn5lS1fV5isIXSaIubvxtBUWzAhflcB1/rs3XkG vMx7X0O68ePoxPm24xlKp8WXhdNVijfPpOdH7n90SOpoTfuVRNF5eOnnwXU/GsmEnW KvoQXjDu+81LQ== From: sashiko-bot@kernel.org Subject: Re: [PATCH 11/11] drm/mediatek: mtk_dp: Clarify XTAL freq and Debounce registers To: "AngeloGioacchino Del Regno" Cc: devicetree@vger.kernel.org, conor+dt@kernel.org, dri-devel@lists.freedesktop.org, robh@kernel.org In-Reply-To: <20260701122024.19557-12-angelogioacchino.delregno@collabora.com> References: <20260701122024.19557-1-angelogioacchino.delregno@collabora.com> <20260701122024.19557-12-angelogioacchino.delregno@collabora.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 01 Jul 2026 14:09:15 +0000 Message-Id: <20260701140915.D151E1F000E9@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 1 potential issue(= s) to consider: - [Medium] Incorrect mask definitions for HPD interrupt thresholds causing = them to evaluate to 0 and conceptually overlap with debounce thresholds. -- commit 7214d6f29b496392f70fbd0b4f1b03755f68eecb Author: AngeloGioacchino Del Regno drm/mediatek: mtk_dp: Clarify XTAL freq and Debounce registers This commit clarifies the meaning of the sub-fields in the crystal frequency and transmitter interrupt debounce registers. The goal is to increase human readability. > diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek= /mtk_dp.c > index 605ead7fa9bf6..b861a5df93167 100644 > --- a/drivers/gpu/drm/mediatek/mtk_dp.c > +++ b/drivers/gpu/drm/mediatek/mtk_dp.c [ ... ] > @@ -1248,28 +1254,29 @@ static void mtk_dp_initialize_aux_hpd_detect_sett= ings(struct mtk_dp *mtk_dp) > =20 > static void mtk_dp_initialize_hpd_detect_settings(struct mtk_dp *mtk_dp) > { > - u32 val; > - > /* Mask AUX TOP interrupt, as this uses transmitter for HPD */ > mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_IRQ_MASK, > AUX_TOP_IRQ_MSK, AUX_TOP_IRQ_MSK); > =20 > - /* Debounce threshold */ > + /* Set Hotplug debounce threshold time: xtal_period * deb_thd */ > mtk_dp_update_bits(mtk_dp, MTK_DP_TRANS_P0_3410, > 8, HPD_DEB_THD_DP_TRANS_P0_MASK); > =20 > - val =3D (HPD_INT_THD_DP_TRANS_P0_LOWER_500US | > - HPD_INT_THD_DP_TRANS_P0_UPPER_1100US) << 4; > - mtk_dp_update_bits(mtk_dp, MTK_DP_TRANS_P0_3410, > - val, HPD_INT_THD_DP_TRANS_P0_MASK); > - > /* > - * Connect threshold 1.5ms + 5 x 0.1ms =3D 2ms > - * Disconnect threshold 1.5ms + 5 x 0.1ms =3D 2ms > + * Set interrupt debounce threshold time > + * VAL | 0 1 2 3 INT_THD > + * Low | 100 300 500 700 uS > + * High | 700 900 1100 1300 uS > */ > - val =3D (5 << 8) | (5 << 12); > mtk_dp_update_bits(mtk_dp, MTK_DP_TRANS_P0_3410, > - val, > + FIELD_PREP_CONST(HPD_INT_LOW_THD_DP_TRANS_P0_MASK, 2) | > + FIELD_PREP_CONST(HPD_INT_HIGH_THD_DP_TRANS_P0_MASK, 2), > + HPD_INT_THD_DP_TRANS_P0_MASK); [Severity: Medium] Will this result in setting the interrupt debounce thresholds to 0? Because HPD_INT_LOW_THD_DP_TRANS_P0_MASK and HPD_INT_HIGH_THD_DP_TRANS_P0_M= ASK are defined as GENMASK(1, 0) and GENMASK(3, 2) instead of their absolute positions within HPD_INT_THD_DP_TRANS_P0_MASK (GENMASK(7, 4)), the values produced by FIELD_PREP_CONST fall outside the update mask.=20 The combined value evaluates to 0xA (bits 3:0), which means the=20 regmap_update_bits() call will silently clear bits 4 through 7 instead of=20 setting them. [ ... ] > diff --git a/drivers/gpu/drm/mediatek/mtk_dp_reg.h b/drivers/gpu/drm/medi= atek/mtk_dp_reg.h > index 9caf743f4fe61..418a2318c656e 100644 > --- a/drivers/gpu/drm/mediatek/mtk_dp_reg.h > +++ b/drivers/gpu/drm/mediatek/mtk_dp_reg.h > @@ -253,6 +253,8 @@ > #define MTK_DP_TRANS_P0_3410 0x1410 > #define HPD_DEB_THD_DP_TRANS_P0_MASK GENMASK(3, 0) > #define HPD_INT_THD_DP_TRANS_P0_MASK GENMASK(7, 4) > +#define HPD_INT_HIGH_THD_DP_TRANS_P0_MASK GENMASK(3, 2) > +#define HPD_INT_LOW_THD_DP_TRANS_P0_MASK GENMASK(1, 0) [Severity: Medium] Are these masks defined at the wrong bit positions? They appear to overlap with HPD_DEB_THD_DP_TRANS_P0_MASK (bits 3:0). If they are meant to be sub-fields of HPD_INT_THD_DP_TRANS_P0_MASK (bits 7:4), shou= ld they be defined as GENMASK(7, 6) and GENMASK(5, 4) instead so they work correctly with FIELD_PREP_CONST()? --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260701122024.1955= 7-1-angelogioacchino.delregno@collabora.com?part=3D11