From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.19]) (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 6F49E1DA2F for ; Thu, 8 Feb 2024 18:37:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.19 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707417449; cv=none; b=OCSkb9uG5Rq0zatIjKjAeGz/LFrRVQu6VvFzN581gaRmKH+0PBD4kdTN5dZds4AnJUNgEaYiUY/BylXycOUUNwq6lNbLAC2aSijvCxFWwoEhHTBdYF7uq5UtfIkSphh4/4gOkqdbqZRZFHlTNudxvI2uSKHLUB3yMBV3fwXYaF4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707417449; c=relaxed/simple; bh=TVM5yl0qA8js6hS+yKnK0nKrrOeE8hgR0HXZPV32EWs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jM9zghO2bKaE4nxcTlDjI/38GYAmWftmiKdpNOgm7k7AFanks95+iBEY2Z46RDi9TcS5wceQHgUvyPFz/AHtvKVlnfpg7ZlPE1VYQx7cyjAUxnKCw1ubH+aiHvWwUrAMNKtDwJhM1rR6xyjr9PMeod3AsNnwGA2qV1x8J8VIEuc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=QinOxiS5; arc=none smtp.client-ip=192.198.163.19 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="QinOxiS5" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1707417448; x=1738953448; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=TVM5yl0qA8js6hS+yKnK0nKrrOeE8hgR0HXZPV32EWs=; b=QinOxiS5blJCZV0meD6Hf3VsS+lZ8T66tAjknTWyeC2SEsTlYw+cfYKu Vuk8NHIkLP/g1Z5YhAMtCVyC4xEoTm/9juvodykx5CEIL3HYex7PfB6wQ 1ve+WuKx7vUncydlOA1FRNUeAEgVNDwSXLVE0QCWVuts0c/Tr9qvfIh/w iHq2fHpqvU0b4QKyrKOoPi1IjyuySOhF78dP45F5vzkoDi5ANdmAFr+6G /sRgEvnY4bmpMGkXMzrzeSu4pHisFo4VKF+dhBKHT+GV+wOrjRptcasMM DvWrFfM/mFvVUMSsypVy6NUcgUV6AzVpXJaswA6NR+8DQwBFJaJfFGsi5 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10978"; a="1183801" X-IronPort-AV: E=Sophos;i="6.05,254,1701158400"; d="scan'208";a="1183801" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmvoesa113.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2024 10:37:27 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10978"; a="934213122" X-IronPort-AV: E=Sophos;i="6.05,254,1701158400"; d="scan'208";a="934213122" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga001.fm.intel.com with ESMTP; 08 Feb 2024 10:37:26 -0800 Received: by black.fi.intel.com (Postfix, from userid 1001) id B3E9586; Thu, 8 Feb 2024 18:09:20 +0200 (EET) Date: Thu, 8 Feb 2024 18:09:20 +0200 From: Mika Westerberg To: Niklas Cassel Cc: Damien Le Moal , Dan Williams , linux-ide@vger.kernel.org Subject: Re: [PATCH] ahci: document and clarify unconventional intel quirk Message-ID: <20240208160920.GT8454@black.fi.intel.com> References: <20240207091054.1697236-1-cassel@kernel.org> Precedence: bulk X-Mailing-List: linux-ide@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20240207091054.1697236-1-cassel@kernel.org> On Wed, Feb 07, 2024 at 10:10:53AM +0100, Niklas Cassel wrote: > The ahci_intel_pcs_quirk is unconventional in several ways: > First of all because it has a board ID for which the quirk should NOT be > applied (board_ahci_pcs7), instead of the usual way where we have a board > ID for which the quirk should be applied. > > The second reason is that other than only excluding board_ahci_pcs7 from > the quirk, PCI devices that make use of the generic entry in ahci_pci_tbl > (which matches on AHCI class code) are also excluded. > > This can of course lead to very subtle breakage, and did indeed do so in: > commit 104ff59af73a ("ata: ahci: Add Tiger Lake UP{3,4} AHCI controller"), > which added an explicit entry with board_ahci_low_power to ahci_pci_tbl. > > This caused many users to complain that their SATA drives disappeared. > The logical assumption was of course that the issue was related to LPM, > and was therefore reverted in commit 6210038aeaf4 ("ata: ahci: Revert > "ata: ahci: Add Tiger Lake UP{3,4} AHCI controller""). > > It took a lot of time to figure out that this was all completely unrelated > to LPM, and was instead caused by an unconventional Intel quirk. > > While this quirk should definitely be cleaned up to be implemented like > all other quirks, for now, at least document the behavior of this quirk. > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=217114 > Signed-off-by: Niklas Cassel Thanks! Reviewed-by: Mika Westerberg