From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792778121; b=dAEisHA8uIwAx+vjn6GjGoJRy7PXjx5iDpQge6yurxj/O1gjH1iVHLqRtjbcynZGF4dN d6W473Q11yqV8IV/JGkpqmNs54cySNQWcWGSP5fGRYHO/4UU3txkJI+xGPsTnJZkIgpBY YaajdZwmiEMkpzzYrsJJtZ57gxjxv9iHL0wN1M5JMHKGffVvAVlpFZPoSuuxMpyZch4wR KKxyi91FcenyO2G7/+wXZPnEXrIQhLZVfZ3cz862LxVNur6wpsIj8cWskhrF7BtwaM3EW GhOlRj42m44XcvjESKAYnhR3q9bkRoU8MLJPsKylVnSYa92Dp9EQlRTVmx1a3KiLSbw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792778121; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=9lze4BcktKCXoOAxLRSh3evuV1ODEFzBfiqGiqkfoDk=; b=hVKuYAoXIe4Ig6EMwazl/SD/+en/W+2pN0UV61F68qYdpceirR7ZcI3T4OirXwSHafCu 1bx997COLN4bFT7ITGSLNFZbYHVYMR5Fi9N7LPO7vP9laZZgeo9F3XcDNZ5yf5Qv0jrKM 9PpeILTr6uvP6HYP9BZrEp2UupotZaCidfAwA7kb2RXIxm4/phyLUJo9W9N6YkuHe6zG0 KVjppuNjQTeCZfF7iSchUM3zwCvMJXnaWnDlwHxj+a6uPeIY8QJhvaSnoHxlMDRKtY3OE 9v9DB8Xg/9Bu//3znFbdhzD9OanwZAmHvG6ne7Qwdm5xUYKw6PYyrVENcuFP4H9ucfQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=HNRZfLgz; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 031B9606A31B for ; Fri, 23 Oct 2026 17:55:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=HNRZfLgz Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79A8D1F01829; Fri, 23 Oct 2026 17:55:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792778120; bh=9lze4BcktKCXoOAxLRSh3evuV1ODEFzBfiqGiqkfoDk=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=HNRZfLgzSfUSwjkArlyGcIhw/u+asMbP628sy39jIFqENk3+6sOZ94Nv6R5/wfqiz CzXy0+QsM4BHiB8qLAn8u/hbkmSQi8XD2WG4hSqvZmMDQpH3uP3Pc7q/+BMiZjdTiT t6tJVJRyGzlocEdACaJAi3mfIx3c9KnTEL7Q1JuIkof+GqmNYPQC7Vs6r010NmTh0K +I4ktH1uZYc2eWnVPdMOGUzNExCUF8mS/J4dWCn26Uo2HtfjD2Ur3f1GlWHIyiwbA/ wpGWXJ5950USm9cVn28sBxMkQw350VIEGKQE83ftBQYqwKIOepE9S/a1dmwDB9ZPMO mjX2WAZW5HsPA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH] PCI: Disable LTR on Qualcomm WCN7850 [17cb:1107] to allow ASPM L1.2 Reply-To: sashiko-reviews@lists.linux.dev To: "Anthony Ruhier" Cc: linux-pci@vger.kernel.org In-Reply-To: <20261023-quick-wcn7850-v1-1-9a139b9b2c8e@mailbox.org> References: <20261023-quick-wcn7850-v1-1-9a139b9b2c8e@mailbox.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 23 Oct 2026 17:55:20 +0000 X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > From: Anthony Ruhier >=20 > The WCN7850 Wifi/BT card, found in several Snapdragon X laptops, never > enters ASPM L1.2 when LTR is enabled. Its firmware reads the > LTR_L1.2_THRESHOLD set at enumeration and reports an LTR value just > below it, so the L1.2 entry condition is never met and the link stays in > L1.1. >=20 > Windows does not set LTR Mechanism Enable for this device (verified by > dumping the ACPI tables), and the link idles in L1.2 normally. >=20 > Replicate the same behavior: clear PCI_EXP_DEVCTL2_LTR_EN for WCN7850 at > enumeration and again on resume, as the LTR state is restored there. >=20 > On a Lenovo Yoga Slim 7x (X1E80100) this allows the link to reach L1.2 > and reduces idle power by about 70 mW. >=20 > Signed-off-by: Anthony Ruhier Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261023-quick-wcn7= 850-v1-1-9a139b9b2c8e@mailbox.org?part=3D1