From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0A236415F0B for ; Fri, 4 Sep 2026 05:31:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788499901; cv=none; b=HPxsNYPyjda0zGCKqMHZsF28LLgGNdPPbI5ESj96/DCjdQKE0B2CzvivX9edCqo1iRTyhtgQze7MVfGqiJ1j2wqa/Is1yQ+Zf5aSjro7riAQvnt/+1oTmaYVxOaoatFADQkFvy119rLOkMwQOlHMqjsRqG48R3sUK8IAJlXo4YA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788499901; c=relaxed/simple; bh=PQ0LSCC8CE7h+rk5S4lsrRjkR+4vvL8vOmkINlKt1j0=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=LIxt2l+coomKqf/RI/jnHMPGiQyvjV9DTCBq2Nn+wSOyAzVS6oRMDz5erDXwEfrxiY/eG0u6pgRxz2PCSpfpsI5j68fmxKlRa3ntG9ouHu0pHj0EpDDXYvxyeOHPsx7Nx1llk8QHZ2jWzVhtxmbNVg8WnkZNx3GnC8RXkZ8uikc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gTkBO1xN; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gTkBO1xN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AD9D91F00A3E; Fri, 4 Sep 2026 05:31:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788499899; bh=8Doe9iwWp0Ky/IVaqjxyyXCP3EZGRKs6wVdlfbkGMv0=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=gTkBO1xNq1md8oRKI68ZUVjlG3MMWjKyXaT0F9B4V9DBVJ1hb3qSukRDR2WXIpYXc FXokRJz1aYgpdpm6QFwPlwn3M+cBWfYmVfCFT1wq8yVH94KM/vP0tjt1Yydil9a5YI 2q5Vesdk4cZt3htgqxpkb3+Gv2mkQQ7MFrQfOIEBAcLT3S98si9UW7YFerR2JVJ3xw aQM3GhzAKqcsn3Ygm0Ik3XWZFz8gxyeHrPUFERCge7It2qjfEWtoFmGiyHn+b9RRmA +q8tpv5DM/kcvYkHKW2cdIL34QQp9eFpdVRsAzr/nrrNBDFMJ4QQpW6/ytpMHHTJmR ZG5K4Ob/1eYHA== From: sashiko-bot@kernel.org Subject: Re: [PATCH v3 2/3] PCI/ASPM: Add pci_aspm_inhibit() helper for temporary link state suppression Reply-To: sashiko-reviews@lists.linux.dev To: "Priyank Rathod" Cc: linux-pci@vger.kernel.org In-Reply-To: <20260904-pcie-link-endpoints-v3-2-4b9a91bd4b35@google.com> References: <20260904-pcie-link-endpoints-v3-0-4b9a91bd4b35@google.com> <20260904-pcie-link-endpoints-v3-2-4b9a91bd4b35@google.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 04 Sep 2026 05:31:39 +0000 Message-Id: <20260904053139.AD9D91F00A3E@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > Currently, pci_disable_link_state() permanently disables ASPM on a PCIe > link by setting link->aspm_disable. However, several kernel subsystems > and driver operations require temporary ASPM inhibition without > permanently disabling power management: > - PCIe Lane Margining at Receiver (LMR): receiver testing requires > the link to remain continuously in L0 throughout the test duration. > - Device firmware updates (e.g. NICs and NVMe controllers): link > latency or L1 transitions during firmware flashing can disrupt > device communication. > - Secondary Bus Reset and link retraining sequences: prevent > unexpected L1/L1SS entry during link reset and recovery. >=20 > Because pci_disable_link_state() cannot be reversed by > pci_enable_link_state() to clear link->aspm_disable, drivers previously > attempted manual manipulations of PCI_EXP_LNKCTL (ASPMC). This > [ ... ] > - When all inhibitors have released (aspm_inhibit_cnt =3D=3D 0), restor= es > the configured ASPM policy to hardware (Upstream Component before > Downstream Component per sec 7.5.3.7 & Table 7-24). >=20 > Signed-off-by: Priyank Rathod Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260904-pcie-link-= endpoints-v3-0-4b9a91bd4b35@google.com?part=3D2