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 DFC24C88E4D for ; Fri, 11 Sep 2026 15:59:55 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0B31C10E3E4; Fri, 11 Sep 2026 15:59:55 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="TLM+tlPC"; 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 423D810E3E4 for ; Fri, 11 Sep 2026 15:59:54 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 15249411C2; Fri, 11 Sep 2026 15:59:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7B2421F000FF; Fri, 11 Sep 2026 15:59:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789142394; bh=e1ZkIJ7dgQuKeYMRuEnRCVfbeVmVIydE09qYycLBhmM=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=TLM+tlPCNKZrtiagr0tyafKrRRijAYaEmSdfTfcRbRijg2M9x1vzVuXCzVrBBTWP6 siMWbT6ATQioBw2Uy95PUTzEOgPOsX/x6Qw01NS2TVq3E5HxKX/j4FiKJ/S2NqhGJY jsWXrFQR4UdjWhG38/W1hSIr45tbl7FDezCKo5+Uj6LaBTiFqn8VAYzaTIZTo3dC7X MJv6srlOyLcFoxnfNSWh8zstQz/nubQsbiZ43HLkKMzAlLhQJTBFL/Nztd9XW/wI4N ddd8X918+b4flL/uXsnllwXEbBkpA2aU10RdDtNOJvqbKPlBPPF93idp8XsUmNmBCn 4cgc1bfmar8yA== From: sashiko-bot@kernel.org Subject: Re: [PATCH 04/17] drm/msm/dpu: Add support for DPU 12.1 on Nord To: "Nabige Aala" Cc: olteanv@gmail.com, devicetree@vger.kernel.org, robh@kernel.org, vkoul@kernel.org, dri-devel@lists.freedesktop.org, neil.armstrong@linaro.org, conor+dt@kernel.org, linux-phy@lists.infradead.org In-Reply-To: <20260911-nord-drv-dt-v1-4-e25c073cf1b6@oss.qualcomm.com> References: <20260911-nord-drv-dt-v1-0-e25c073cf1b6@oss.qualcomm.com> <20260911-nord-drv-dt-v1-4-e25c073cf1b6@oss.qualcomm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 11 Sep 2026 15:59:53 +0000 Message-Id: <20260911155953.7B2421F000FF@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] Adding `INTF_9` and `INTF_10` without corresponding entries in `en= um dpu_hw_intr_reg` causes the `MDP_INTFn_INTR()` macro to silently alias w= ith legacy DSI TEAR interrupts, leading to fatal unclocked hardware accesse= s. - [High] Including inferred, unverified dummy register addresses and bus ma= pper IDs in an upstream hardware catalog. -- commit bd1cb43210104c822d361350ae75f5b63854edc7 Author: Mahadevan P drm/msm/dpu: Add support for DPU 12.1 on Nord This commit adds the DPU catalog entry for the Qualcomm Nord SoC (MDSS 12.1= ), a DP-only chip with 8 DSPP blocks, 2 writeback blocks, 8 interfaces and 2 DP controllers. It extends the interface enum with INTF_9 and INTF_10 and adds inferred hardware catalog entries marked with FIXME. > diff --git a/drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_12_1_nord.h b/driv= ers/gpu/drm/msm/disp/dpu1/catalog/dpu_12_1_nord.h > new file mode 100644 > index 0000000000000..8eb18752f3c4b > --- /dev/null > +++ b/drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_12_1_nord.h [ ... ] > +static const struct dpu_wb_cfg nord_wb[] =3D { > + { > + .name =3D "wb_1", .id =3D WB_1, > + .base =3D 0x64800, .len =3D 0x2c8, /* FIXME(REG_ADDR): inferred */ > + .features =3D WB_SDM845_MASK, > + .format_list =3D wb2_formats_rgb_yuv, > + .num_formats =3D ARRAY_SIZE(wb2_formats_rgb_yuv), > + .xin_id =3D 7, /* FIXME(XIU_MAP): inferred */ [Severity: High] Is it safe to include inferred register base addresses and bus mapper IDs t= hat haven't been verified against actual hardware? When the driver probes on Nord, it will unconditionally map and access these unverified addresses. If the inferred base address is incorrect, accessing this region will likely hit invalid physical memory and cause an immediate bus error. [ ... ] > +static const struct dpu_intf_cfg nord_intf[] =3D { > + { [ ... ] > + .name =3D "intf_4", .id =3D INTF_4, > + .base =3D 0x38000, .len =3D 0x4bc, /* FIXME(REG_ADDR): new, stride +0x= 1000 */ [Severity: High] Similarly here, will accessing this unverified INTF_4 base address cause a system crash if the guessed stride is incorrect for this SoC? [ ... ] > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h b/drivers/gpu/dr= m/msm/disp/dpu1/dpu_hw_mdss.h > index 0e65bf5ddc4a6..7eccb4d2c65ef 100644 > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h > @@ -226,6 +226,8 @@ enum dpu_intf { > INTF_6, > INTF_7, > INTF_8, > + INTF_9, > + INTF_10, > INTF_MAX > }; [Severity: High] Does adding INTF_9 and INTF_10 without updating enum dpu_hw_intr_reg cause an interrupt mapping collision? Looking at MDP_INTFn_INTR in dpu_hw_interrupts.h: #define MDP_INTFn_INTR(intf) (MDP_INTF0_INTR + (intf - INTF_0)) When this maps INTF_9 (index 10) and INTF_10 (index 11), they evaluate to offsets 12 and 13 respectively. In enum dpu_hw_intr_reg, offsets 12 and 13 are already mapped to MDP_INTF1_TEAR_INTR and MDP_INTF2_TEAR_INTR. During driver probe, dpu_hw_intr_init() uses this macro to populate the irq_mask. Since Nord is DP-only and explicitly lacks the INTF_1 and INTF_2 hardware blocks, will dpu_clear_irqs() iterating over this mask attempt to write to unmapped TEAR registers and cause an unrecoverable bus fault? --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260911-nord-drv-d= t-v1-0-e25c073cf1b6@oss.qualcomm.com?part=3D4