From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 BA1A23C2F for ; Fri, 27 Jun 2025 07:35:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751009740; cv=none; b=ECmbRr7yETYCxg1vM0N9Y/H1ds4+l+ELBhqJtLtHrxNPFehtNzfGrQzW/fG/plnebu8Mz6NQpGtdWycKlKxOEH1VCLCitaFJn6OY+iXH3mjqehlZOz4dGJRUpfdBX6EBEE0Qk4O+DrxsskW4C8mleAOHDaMh4A5zcYiLH8qG3Ms= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751009740; c=relaxed/simple; bh=k3HCmxRJedGUsbcBuUX+/pQjxijqs2PRbzhkSoMl8lE=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=VDMshJO9orTaOGKpxggPeKlWNvl6QtvReURHS68O+JbBABZREWmdWp7wi+JxOnTLCLCfHerDEOpPFNko7RPy46rXWNVhSg4xe8xmssMlDCjt811NF5+N7wlciGCgE3ibp8prsS9IzVEHCa1Wn+56wzfqN+Ify2XtT9CbiSfagbs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=aQilk21I; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="aQilk21I" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BE584C4CEE3; Fri, 27 Jun 2025 07:35:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1751009740; bh=k3HCmxRJedGUsbcBuUX+/pQjxijqs2PRbzhkSoMl8lE=; h=Date:Subject:To:References:From:In-Reply-To:From; b=aQilk21IZr8Em7tl6urxaRREePUmTBXM8JfXpINCCBjTz7ISxmL/Ox41KF2I/qH4+ RGqNTCLpyxZY8pIw+2PtPi9pmwbKl5UXLWYjwKsZOi65TCjQRm1dfVsdrt6Ol4Uqty FB/odqEZwbaypz5Pshw427pQPSISerD+tVddwqhD1ZLqboxWkXO+j+C+I9KW3xRao5 C7N9KzJcAcTq6qWrT3tGfKwvAw/LddBzZessg58I7YZ+l96HUGpaDaL6yZwFtWYem1 iNo5sz5SktUsPR7IrdFd5SefA8yjxGwZVA2ivf5rvzrAJ/je1NO5HfcaWcHvl7poeb hJRPI7f08eHng== Message-ID: <5b3d302b-c4e5-4061-959c-e60b1ec1bc6a@kernel.org> Date: Fri, 27 Jun 2025 16:35:38 +0900 Precedence: bulk X-Mailing-List: linux-ide@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 3/6] ata: Fix SATA_MOBILE_LPM_POLICY description in Kconfig To: Hannes Reinecke , linux-ide@vger.kernel.org, Niklas Cassel References: <20250627011155.701125-1-dlemoal@kernel.org> <20250627011155.701125-4-dlemoal@kernel.org> <347157db-8a01-47ae-9dba-c46c77bae824@suse.de> Content-Language: en-US From: Damien Le Moal Organization: Western Digital Research In-Reply-To: <347157db-8a01-47ae-9dba-c46c77bae824@suse.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/27/25 15:03, Hannes Reinecke wrote: > On 6/27/25 03:11, Damien Le Moal wrote: >> Improve the description of the possible default SATA link power >> management policies and add the missing description for policy 5. >> No functional changes. >> >> Fixes: a5ec5a7bfd1f ("ata: ahci: Support state with min power but Partial low power state") >> Cc: stable@vger.kernel.org >> Signed-off-by: Damien Le Moal >> --- >> drivers/ata/Kconfig | 36 ++++++++++++++++++++++++++---------- >> 1 file changed, 26 insertions(+), 10 deletions(-) >> >> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig >> index e00536b49552..1d53d7b568bd 100644 >> --- a/drivers/ata/Kconfig >> +++ b/drivers/ata/Kconfig >> @@ -117,23 +117,39 @@ config SATA_AHCI >> >> config SATA_MOBILE_LPM_POLICY >> int "Default SATA Link Power Management policy" >> - range 0 4 >> + range 0 5 >> default 3 >> depends on SATA_AHCI >> help >> Select the Default SATA Link Power Management (LPM) policy to use >> for chipsets / "South Bridges" supporting low-power modes. Such >> chipsets are ubiquitous across laptops, desktops and servers. >> - >> - The value set has the following meanings: >> + Each policy combines power saving states and features: >> + - Partial: The Phy logic is powered but is in a reduced power >> + state. The exit latency from this state is no longer than >> + 10us). >> + - Slumber: The Phy logic is powered but is in an even lower power >> + state. The exit latency from this state is potentially >> + longer, but no longer than 10ms. >> + - DevSleep: The Phy logic may be powered down. The exit latency from >> + this state is no longer than 20 ms, unless otherwise >> + specified by DETO in the device Identify Device Data log. >> + - HIPM: Host Initiated Power Management (host automatic transisitons >> + to partial and slumber). >> + - DIPM: Device Initiated Power Management (device automatic >> + transitions to partial and slumber). >> + >> + The possible values for the default SATA link power management >> + policies are: >> 0 => Keep firmware settings >> - 1 => Maximum performance >> - 2 => Medium power >> - 3 => Medium power with Device Initiated PM enabled >> - 4 => Minimum power >> - >> - Note "Minimum power" is known to cause issues, including disk >> - corruption, with some disks and should not be used. >> + 1 => No power savings (maximum performance) >> + 2 => HIPM (Partial) >> + 3 => HIPM (Partial) and DIPM (Partial and Slumber) >> + 4 => HIPM (Partial and DevSleep) and DIPM (Partial and Slumber) >> + 5 => HIPM (Slumber and DevSleep) and DIPM (Partial and Slumber) >> + >> + Excluding the value 0, higher values represent policies with higher >> + power savings. >> >> config SATA_AHCI_PLATFORM >> tristate "Platform AHCI SATA support" > > Hmm. Isn't it worth creating an official documentation somewhere in > Documentation/* to have this available without having to look at the > source code? Yes, I am considering this. I did not write it in the cover letter, but these patches are the first part of a much bigger patch series that addresses a lot of LPM issues that we recently discovered doing completely unrelated tests. Once that is out, documenting everything will be a good thing to do. > > Otherwise: > Reviewed-by: Hannes Reinecke > > Cheers, > > Hannes -- Damien Le Moal Western Digital Research