From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 11D237EB for ; Mon, 29 Apr 2024 02:12:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714356741; cv=none; b=G3WG+ro+dxuZh3V+AjVVbbatj5yYn1T1J7tP0gK52KnRKuBTQ8LIsX6uHM4xp4pZhn+pmVDOrX7vmEAt/Tc2Hy3OBh4a26sRdkigLBIvvh8GLVxZ+wdXnUSEqSR62WDNILaDazP92lDO/LiTzW2sHR6ByVd/J0k0EJp3MfSMSF0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714356741; c=relaxed/simple; bh=TjzGRrlLJm+93DR1oj1ImEevOHZ4wp09edRjCQW9RBA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Hrazjq8rv2nVdyTQ0LTuQG+bIgI00vpYIS9DHN4+k5Rz0oPAhtN7nFvU2+mpxha0iKC6XPOPA9TwvzSkuWtsXnu2PZmDaFq055W7vTbNE6cQEEmiGDiKkycMKTZ9uhYYuSdA6brAjxXqPcf09FK0CDrgeIpY+4i7W32i463+Spg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 85EE22F4; Sun, 28 Apr 2024 19:04:37 -0700 (PDT) Received: from [10.162.42.72] (a077893.blr.arm.com [10.162.42.72]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C04213F73F; Sun, 28 Apr 2024 19:04:08 -0700 (PDT) Message-ID: <7abe77fa-e9bb-4f50-86a8-5bae530bf068@arm.com> Date: Mon, 29 Apr 2024 07:34:05 +0530 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] arm64/sysreg: Update ID_AA64MMFR2_EL1 register Content-Language: en-US To: Mark Brown , Will Deacon Cc: linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, linux-kernel@vger.kernel.org References: <20240419021325.2880384-1-anshuman.khandual@arm.com> <20240419134623.GE3148@willie-the-truck> <49365864-0080-4ddd-b0cb-eef41c88b6a9@arm.com> <20240422171613.GC6223@willie-the-truck> From: Anshuman Khandual In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 4/23/24 10:47, Mark Brown wrote: > On Mon, Apr 22, 2024 at 06:16:13PM +0100, Will Deacon wrote: >> On Mon, Apr 22, 2024 at 08:38:40AM +0530, Anshuman Khandual wrote: > >>> This is not being used currently but will be required for upcoming >>> features. I was under the impression that register fields (atleast >>> for the ID registers) should be kept updated, with latest released >>> spec ? Besides lately arch/arm64/tools/sysreg serves as very good >>> reference for all necessary register fields. > >> Why? The linux headers aren't documenting the architecture. > > I don't know that it's something that we should be doing apropos of > nothing but if people have done updates and they're not unreasonbly > complicated to review it does seem useful to integrate them to avoid > duplicated work. There have been some issues with that around the ID > registers (which are going to be on the places most prone to this I > guess). The other problem is by not updating the individual register fields with the latest spec, it also gives an wrong impression about that field, and also might create confusion.