From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) (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 517E517A93D for ; Mon, 12 Aug 2024 12:17:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723465067; cv=none; b=tFTXcqX0jCjllo/onunWJJUIjpUL2dnhJpXHXItezvanlXiAYmr1vCQLLB5PpOeb63bewnEt4iW9cab8JTM9kIl83oW8eL/plw5diPSliZRgwHDWOIsQLys4sc0rx4JRtZMVdfzuU8lpukPFqhHOlBPVlp82HS/giBofdldD+1Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723465067; c=relaxed/simple; bh=zVrE1ziOBDm89ZZUuFAl8nfIqMixay1u8ld1OLeodv0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ZxLNEa2G5KvyAHn8FzQ27Bgh5IBr9FmZsndUXrLEXfVbmDy+6SkMwOcXRSKXMSl6x7MdB5Vrqp0cGhyLD+hf3Sg6AafOv+S8kRdgXXJSpP0FtANvT84PDelaqwOqXr71V/rbKluR2GSpfCci3/ghVSEkZs5Fp7dNo97LVRSPRGw= 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=nn5nPnVg; arc=none smtp.client-ip=198.175.65.16 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="nn5nPnVg" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1723465066; x=1755001066; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=zVrE1ziOBDm89ZZUuFAl8nfIqMixay1u8ld1OLeodv0=; b=nn5nPnVgKDtgwwllY2fH/nygwBvCE7IUZ3+fgb+j521D/Nkv9IyGnsGw Op+uJXGnkqf9QE+f8xeG4XUpMRZKkfKL7DhoWYkDsiv3FnlDRcspihFCp Wvts6q7rDpMoh8Kd+YG7ND8gQWfmEt08JbJbEy3w9wU/h/0YjLfhBn/W4 hwNUjKb5JoG84SdOadB3CttAQtWxfPd1awrbCsRaIGHjzBegOdmK2NnYY nIzbw0isLZ1iXVj1KvStQxbx7YKMoisERYQt9EYgL+/FTmqu9oh5b3zs9 wNIXhb7oMdFCXx4+zga2lzLkI6vk5VsCu4xIHfSeciTGyver/pxE3yKrJ Q==; X-CSE-ConnectionGUID: cQnCucCaR1iUA+PE+WjH3Q== X-CSE-MsgGUID: pVPcU3cLTtmOIxCK6sjX+A== X-IronPort-AV: E=McAfee;i="6700,10204,11162"; a="21720290" X-IronPort-AV: E=Sophos;i="6.09,282,1716274800"; d="scan'208";a="21720290" Received: from orviesa002.jf.intel.com ([10.64.159.142]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Aug 2024 05:17:45 -0700 X-CSE-ConnectionGUID: 57/tv0/BTxaAFt7q5/9cNA== X-CSE-MsgGUID: fSWgTmkJQVeSD94EkS4KXw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.09,282,1716274800"; d="scan'208";a="88898350" Received: from smile.fi.intel.com ([10.237.72.54]) by orviesa002.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Aug 2024 05:17:43 -0700 Received: from andy by smile.fi.intel.com with local (Exim 4.98) (envelope-from ) id 1sdTzY-0000000EKru-32P6; Mon, 12 Aug 2024 15:17:40 +0300 Date: Mon, 12 Aug 2024 15:17:40 +0300 From: Andy Shevchenko To: Alexandre Belloni Cc: Shyam Sundar S K , Jarkko Nikula , Guruvendra Punugupati , Krishnamoorthi M , linux-i3c@lists.infradead.org, linux-kernel@vger.kernel.org, "Rafael J. Wysocki" Subject: Re: [PATCH RESEND v3 1/6] i3c: mipi-i3c-hci: Add MIPI0100 ACPI ID to the I3C Support List Message-ID: References: <20240807052359.290046-1-Shyam-sundar.S-k@amd.com> <20240807052359.290046-2-Shyam-sundar.S-k@amd.com> <20240809183940461e3838@mail.local> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240809183940461e3838@mail.local> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo On Fri, Aug 09, 2024 at 08:39:40PM +0200, Alexandre Belloni wrote: > On 09/08/2024 18:57:04+0300, Andy Shevchenko wrote: > > > Please refer to the MIPI HCI I3C DisCo specification > > > (https://members.mipi.org/wg/All-Members/document/previewpdf/89465) > > > section 5.4. The ASL looks the same in case of AMD. > > > > > > MSFT says that they want to use MIPI0100 as mentioned in the > > > specification. > > > > MIPI doesn't know how to assign the ACPI ID correctly. But again, what I put in > > the above is the correct way of approaching. > > > > > What would you advise? > > > > Since my intuition and experience tells me that the two devices even based on > > the same IP are not the same (see word 'quirk' or '.driver_data' or alike in > > the kernel sources) the generic ID may not be used for the specific vendor > > unless it's _the only_ vendor for the certain IP. > > Just to be clear, the HCI defines the register interface to the IP but > not the IP itself, this is just like the various USB and SD HCIs. Thank you for this elaboration, it's a crucial aspect! > So we will definitively see quirks as implementers will interpret the > interface differently With the above remark this makes a lot of sense. > (and so I agree with everything that was said ;) ) > > So, please do as I suggested above. And file a error report (and correction > > proposal) to the MIPI, so in "5.1 I3C Host Controller ACPI Hardware ID (_HID)" > > they should use _CID instead of _HID and add some text like > > "Each vendor should dedicate it's own _HID for the platform in question. The > > same _HID as _CID may be used if and only if vendor guarantees that there 100% > > compatibility with MIPI as described in this and other related documents." > > > > I.o.w. do you 100% guarantee that MIPI HCI I3C DisCo covers all necessary > > properties that you need for _your_ hardware? If not, use my approach, if yes, > > use the same _HID *and* _CID. > > > > Microsoft should know this as well and much better than MIPI. -- With Best Regards, Andy Shevchenko