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 59569C61DD3 for ; Tue, 1 Sep 2026 08:55:30 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 90D2910EC08; Tue, 1 Sep 2026 08:55:29 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="SiUwXMxj"; 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 B871810EC08 for ; Tue, 1 Sep 2026 08:55:27 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 7F95441492; Tue, 1 Sep 2026 08:55:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F9951F000E9; Tue, 1 Sep 2026 08:55:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788252927; bh=F7NP2+aACTgvDtigo+/r4ZBJvQ4uqczsBwLqSVNHXgQ=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=SiUwXMxjG+66/FodulCHeCv65kZQLM/DvqOuc6PN+2NMfPR4Gz7JdwhR3f561Fcu9 sOqOH09KolSES7MYJyIUDCT3yuVNff8thuiADBjmzy7av1gY3ey8UW97k5FMEIZWiZ UoKjZMHUS2P6ozqyFOQGBOe6FePS/6yRaZIr4QdWPS2tDp6QfUEMmnbpuEd6dZeyA8 QE6gnY+gYbqGy1XxcQmcWuMJ8c0L3zwgnegOHMQO04TPmuTPdQWbMZkQ2JNAHi4xJF 5hDC3oFFkyNdOeFPIkzetzgPcnsN+P7dceKZzwMWI8nk5rxLFp6PGXHG1q8PaZ65qf 64cexfcYueC4Q== From: sashiko-bot@kernel.org Subject: Re: [PATCH 1/6] PCI: of: Avoid config reads for disabled bridge nodes To: "Xilin Wu" Cc: conor+dt@kernel.org, robh@kernel.org, dri-devel@lists.freedesktop.org, linux-pci@vger.kernel.org, devicetree@vger.kernel.org In-Reply-To: <20260901-q8b-dts-v1-1-7de0b6a73d08@radxa.com> References: <20260901-q8b-dts-v1-0-7de0b6a73d08@radxa.com> <20260901-q8b-dts-v1-1-7de0b6a73d08@radxa.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 01 Sep 2026 08:55:26 +0000 Message-Id: <20260901085527.0F9951F000E9@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" > The TC9563 PCI power-control driver powers off external downstream ports > whose device tree nodes have status =3D "disabled". >=20 > On the Radxa Dragon Q8B, reading the Vendor ID from one of these > powered-off port functions during PCI enumeration raises an Arm SError > instead of returning an all-ones PCI error response. This prevents the > board from completing boot. >=20 > Commit 1a8c251cff20 ("PCI: move OF status =3D "disabled" detection to > dev->match_driver") made disabled PCI functions remain discoverable so > PCI fixups can still be applied, while suppressing driver binding later. > Preserve that behavior for endpoint functions. >=20 > For an unavailable node describing a PCI-to-PCI bridge, however, the > node also represents a subordinate bus that must not be enumerated. > Check the device tree node before reading the Vendor ID and return a PCI > error response without accessing config space when such a bridge is > disabled. >=20 > Functions not described by device tree and disabled endpoint functions > remain discoverable. >=20 > Signed-off-by: Xilin Wu Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260901-q8b-dts-v1= -0-7de0b6a73d08@radxa.com?part=3D1