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 X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B2FB5C8300F for ; Mon, 23 Nov 2020 13:30:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 84276206E3 for ; Mon, 23 Nov 2020 13:30:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730045AbgKWNaJ (ORCPT ); Mon, 23 Nov 2020 08:30:09 -0500 Received: from mga12.intel.com ([192.55.52.136]:39747 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730433AbgKWM2Z (ORCPT ); Mon, 23 Nov 2020 07:28:25 -0500 IronPort-SDR: g6kiLp0alnjDszK1FywFdHtvE07XUy9eKM1dgdqkXoMehl3edzASSJbDzItxPS1ZHW4WsMzeDj 2cOE4wgJfBjA== X-IronPort-AV: E=McAfee;i="6000,8403,9813"; a="151014826" X-IronPort-AV: E=Sophos;i="5.78,363,1599548400"; d="scan'208";a="151014826" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2020 04:28:24 -0800 IronPort-SDR: TbsQts1Ebsd/jXlkCtu/xtZK2kGWO6LGzpGbGYQ1OjfmX7ABhZYHl79HvLh7PL34yRmGie0pUA X3P7WBBnb43g== X-IronPort-AV: E=Sophos;i="5.78,363,1599548400"; d="scan'208";a="361427424" Received: from lahna.fi.intel.com (HELO lahna) ([10.237.72.163]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2020 04:28:22 -0800 Received: by lahna (sSMTP sendmail emulation); Mon, 23 Nov 2020 14:28:20 +0200 Date: Mon, 23 Nov 2020 14:28:20 +0200 From: Mika Westerberg To: Christoph Hellwig Cc: Jens Axboe , linux-ide@vger.kernel.org Subject: Re: [PATCH] ahci: Add Intel Emmitsburg PCH RAID PCI IDs Message-ID: <20201123122820.GD2495@lahna.fi.intel.com> References: <20201119104318.79297-1-mika.westerberg@linux.intel.com> <20201119165022.GA3582@infradead.org> <20201120105309.GR2495@lahna.fi.intel.com> <20201123100917.GA26718@infradead.org> <20201123112622.GB2495@lahna.fi.intel.com> <20201123113801.GA15759@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201123113801.GA15759@infradead.org> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-ide@vger.kernel.org On Mon, Nov 23, 2020 at 11:38:01AM +0000, Christoph Hellwig wrote: > The point is: these AHCI controllers do not support RAID in form > despite the confusing naming. Are you sure? I looked at the Emmitsburg data sheet and it actually seems to support some sort of RAID but it requires some special Rapid Storage Technology [1] drivers from Intel. Probably the idea is that when in "RAID mode" the thing, as AHCI spec says, does not announce itself to be AHCI compliant which makes Windows inbox AHCI driver to not to load, and this allows the Intel propriatery driver to load that then takes advantage of this somehow. I'm not too familiar with these technologies here so I may be missing something. [1] https://www.intel.com/content/www/us/en/architecture-and-technology/rapid-storage-technology.html