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 D78E3270552; Sat, 28 Feb 2026 09:54:35 +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=1772272475; cv=none; b=C9vJDJqWLEtb8vP7QbD+aPErrMpST5Hche0zFk9tvXzDXS8pDsZ/XIB0sieBc/kHGwBYckOYewzVHCIVMRsELxla/nz9WGZQf6VNCzOkoPTDjcGCxISz2b0PwKkUPMnL966ENQ6ogVav5zi66iOgwDUQ6Z5sjy5SCWp5Y8/58Ck= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772272475; c=relaxed/simple; bh=YouXqvnP0taKGHklJH5cIaDhX7R1/igobBji1f49w58=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=T9cqaCZxmKRhh7DdlQWj+OUtcIKJ5VXnu8tdxhu5dWEOLTxzdrXpP6lQhlre1RmhQn3w2Sai6+xklZHoHN5G87wSAPJm1PnxkSQBiiKrYA8ZwJwtyJk33k1kJRJVxyh3s5VjqkKUBTjbsY1WLvvY94HQpEF4Pyrvb3++Sl1nvsk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eLr0iciQ; 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="eLr0iciQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A7A02C116D0; Sat, 28 Feb 2026 09:54:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772272475; bh=YouXqvnP0taKGHklJH5cIaDhX7R1/igobBji1f49w58=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=eLr0iciQqYzyeJegC9ou3JYzCPQGiRD6iyZk/FvAPJn7LjWxoZCtM9mZr+ncM/IW/ LSnEl+FRkXITDqIyh9SAOPbl9xIV1MhTl6JHOZ/Y16XydHloEF/vqe4/qieBsfx8wE Ta9hdkqnPNzXNldxX2Rut8glRmPPoF/Nvo8TFkfURHkH+pam8Nm2TMgcEOwV2RQQlo 0rVWcx05ELDSSA0FDwZD6aglEUC65FLDa42tIqHqIZ8iOq2mEU1leUp3TCLVmKshfI WRodMOJvn8/UeHbzi1v6FWPd1rRBW9qr+AIGBBG9Q8rxs2pxGu3OSGNjPbc1+z+M4r yp2ft605pTPuw== Message-ID: <1fe5529f-cd9f-4960-b6dd-96a2d02b8d86@kernel.org> Date: Sat, 28 Feb 2026 10:54:29 +0100 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 1/3] media: dt-bindings: rockchip,vdec: Add alternative reg-names order for RK35{76,88} To: Cristian Ciocaltea , Conor Dooley Cc: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Heiko Stuebner , Detlev Casanova , Ezequiel Garcia , Mauro Carvalho Chehab , Nicolas Dufresne , Hans Verkuil , kernel@collabora.com, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org, Conor Dooley , linux-media@vger.kernel.org References: <20260226-vdec-reg-order-rk3576-v4-0-b8d72dc75250@collabora.com> <20260226-vdec-reg-order-rk3576-v4-1-b8d72dc75250@collabora.com> <20260227-observant-roaring-ara-ef7eb0@quoll> <20260227-omission-stoic-417d7109ad4d@spud> <3ab4f91e-37d0-4950-af88-01920705d31a@collabora.com> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; keydata= xsFNBFVDQq4BEAC6KeLOfFsAvFMBsrCrJ2bCalhPv5+KQF2PS2+iwZI8BpRZoV+Bd5kWvN79 cFgcqTTuNHjAvxtUG8pQgGTHAObYs6xeYJtjUH0ZX6ndJ33FJYf5V3yXqqjcZ30FgHzJCFUu JMp7PSyMPzpUXfU12yfcRYVEMQrmplNZssmYhiTeVicuOOypWugZKVLGNm0IweVCaZ/DJDIH gNbpvVwjcKYrx85m9cBVEBUGaQP6AT7qlVCkrf50v8bofSIyVa2xmubbAwwFA1oxoOusjPIE J3iadrwpFvsZjF5uHAKS+7wHLoW9hVzOnLbX6ajk5Hf8Pb1m+VH/E8bPBNNYKkfTtypTDUCj NYcd27tjnXfG+SDs/EXNUAIRefCyvaRG7oRYF3Ec+2RgQDRnmmjCjoQNbFrJvJkFHlPeHaeS BosGY+XWKydnmsfY7SSnjAzLUGAFhLd/XDVpb1Een2XucPpKvt9ORF+48gy12FA5GduRLhQU vK4tU7ojoem/G23PcowM1CwPurC8sAVsQb9KmwTGh7rVz3ks3w/zfGBy3+WmLg++C2Wct6nM Pd8/6CBVjEWqD06/RjI2AnjIq5fSEH/BIfXXfC68nMp9BZoy3So4ZsbOlBmtAPvMYX6U8VwD TNeBxJu5Ex0Izf1NV9CzC3nNaFUYOY8KfN01X5SExAoVTr09ewARAQABzSVLcnp5c3p0b2Yg S296bG93c2tpIDxrcnprQGtlcm5lbC5vcmc+wsGVBBMBCgA/AhsDBgsJCAcDAgYVCAIJCgsE FgIDAQIeAQIXgBYhBJvQfg4MUfjVlne3VBuTQ307QWKbBQJoF1BKBQkWlnSaAAoJEBuTQ307 QWKbHukP/3t4tRp/bvDnxJfmNdNVn0gv9ep3L39IntPalBFwRKytqeQkzAju0whYWg+R/rwp +r2I1Fzwt7+PTjsnMFlh1AZxGDmP5MFkzVsMnfX1lGiXhYSOMP97XL6R1QSXxaWOpGNCDaUl ajorB0lJDcC0q3xAdwzRConxYVhlgmTrRiD8oLlSCD5baEAt5Zw17UTNDnDGmZQKR0fqLpWy 786Lm5OScb7DjEgcA2PRm17st4UQ1kF0rQHokVaotxRM74PPDB8bCsunlghJl1DRK9s1aSuN hL1Pv9VD8b4dFNvCo7b4hfAANPU67W40AaaGZ3UAfmw+1MYyo4QuAZGKzaP2ukbdCD/DYnqi tJy88XqWtyb4UQWKNoQqGKzlYXdKsldYqrLHGoMvj1UN9XcRtXHST/IaLn72o7j7/h/Ac5EL 8lSUVIG4TYn59NyxxAXa07Wi6zjVL1U11fTnFmE29ALYQEXKBI3KUO1A3p4sQWzU7uRmbuxn naUmm8RbpMcOfa9JjlXCLmQ5IP7Rr5tYZUCkZz08LIfF8UMXwH7OOEX87Y++EkAB+pzKZNNd hwoXulTAgjSy+OiaLtuCys9VdXLZ3Zy314azaCU3BoWgaMV0eAW/+gprWMXQM1lrlzvwlD/k whyy9wGf0AEPpLssLVt9VVxNjo6BIkt6d1pMg6mHsUEVzsFNBFVDXDQBEADNkrQYSREUL4D3 Gws46JEoZ9HEQOKtkrwjrzlw/tCmqVzERRPvz2Xg8n7+HRCrgqnodIYoUh5WsU84N03KlLue MNsWLJBvBaubYN4JuJIdRr4dS4oyF1/fQAQPHh8Thpiz0SAZFx6iWKB7Qrz3OrGCjTPcW6ei OMheesVS5hxietSmlin+SilmIAPZHx7n242u6kdHOh+/SyLImKn/dh9RzatVpUKbv34eP1wA GldWsRxbf3WP9pFNObSzI/Bo3kA89Xx2rO2roC+Gq4LeHvo7ptzcLcrqaHUAcZ3CgFG88CnA 6z6lBZn0WyewEcPOPdcUB2Q7D/NiUY+HDiV99rAYPJztjeTrBSTnHeSBPb+qn5ZZGQwIdUW9 YegxWKvXXHTwB5eMzo/RB6vffwqcnHDoe0q7VgzRRZJwpi6aMIXLfeWZ5Wrwaw2zldFuO4Dt 91pFzBSOIpeMtfgb/Pfe/a1WJ/GgaIRIBE+NUqckM+3zJHGmVPqJP/h2Iwv6nw8U+7Yyl6gU BLHFTg2hYnLFJI4Xjg+AX1hHFVKmvl3VBHIsBv0oDcsQWXqY+NaFahT0lRPjYtrTa1v3tem/ JoFzZ4B0p27K+qQCF2R96hVvuEyjzBmdq2esyE6zIqftdo4MOJho8uctOiWbwNNq2U9pPWmu 4vXVFBYIGmpyNPYzRm0QPwARAQABwsF8BBgBCgAmAhsMFiEEm9B+DgxR+NWWd7dUG5NDfTtB YpsFAmgXUF8FCRaWWyoACgkQG5NDfTtBYptO0w//dlXJs5/42hAXKsk+PDg3wyEFb4NpyA1v qmx7SfAzk9Hf6lWwU1O6AbqNMbh6PjEwadKUk1m04S7EjdQLsj/MBSgoQtCT3MDmWUUtHZd5 RYIPnPq3WVB47GtuO6/u375tsxhtf7vt95QSYJwCB+ZUgo4T+FV4hquZ4AsRkbgavtIzQisg Dgv76tnEv3YHV8Jn9mi/Bu0FURF+5kpdMfgo1sq6RXNQ//TVf8yFgRtTUdXxW/qHjlYURrm2 H4kutobVEIxiyu6m05q3e9eZB/TaMMNVORx+1kM3j7f0rwtEYUFzY1ygQfpcMDPl7pRYoJjB dSsm0ZuzDaCwaxg2t8hqQJBzJCezTOIkjHUsWAK+tEbU4Z4SnNpCyM3fBqsgYdJxjyC/tWVT AQ18NRLtPw7tK1rdcwCl0GFQHwSwk5pDpz1NH40e6lU+NcXSeiqkDDRkHlftKPV/dV+lQXiu jWt87ecuHlpL3uuQ0ZZNWqHgZoQLXoqC2ZV5KrtKWb/jyiFX/sxSrodALf0zf+tfHv0FZWT2 zHjUqd0t4njD/UOsuIMOQn4Ig0SdivYPfZukb5cdasKJukG1NOpbW7yRNivaCnfZz6dTawXw XRIV/KDsHQiyVxKvN73bThKhONkcX2LWuD928tAR6XMM2G5ovxLe09vuOzzfTWQDsm++9UKF a/A= In-Reply-To: <3ab4f91e-37d0-4950-af88-01920705d31a@collabora.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 27/02/2026 18:42, Cristian Ciocaltea wrote: > On 2/27/26 7:13 PM, Conor Dooley wrote: >> On Fri, Feb 27, 2026 at 01:37:17PM +0200, Cristian Ciocaltea wrote: >>> Hi Krzysztof, Conor, >>> >>> On 2/27/26 9:46 AM, Krzysztof Kozlowski wrote: >>>> On Thu, Feb 26, 2026 at 12:46:53PM +0200, Cristian Ciocaltea wrote: >>>>> With the introduction of the RK3588 SoC, and RK3576 afterwards, two more >>>>> register blocks have been provided for the video decoder unit. >>>>> >>>>> However, the binding does not properly describe the new hardware layout, >>>> >>>> As you shown me last time with excerpt of address spaces from >>>> datasheet/manual, the binding correctly describes the hardware and above >>>> sentence is not true. >>>> >>>>> as it breaks the convention expecting the unit address to indicate the >>>>> start of the first register range, i.e. 'function' block is listed >>>> >>>> Imprecise wording. "start of the main or primary register range" >>>> >>>> (if you have 0x1000 with one reg and 0x20000000 with everything, the >>>> unit address will be 0x20000000). >>>> >>>>> before 'link' instead of the opposite. >>>>> >>>>> Since the binding changes have been already released and a fix would >>>>> bring up an ABI break, mark the current 'reg-names' ordering as >>>>> deprecated and introduce an alternative 'link,function,cache' listing >>>>> which follows the address-based ordering according to the TRM. >>>>> >>>>> Additionally, drop the 'reg' description items as the order is not fixed >>>>> anymore, while the information they offer is not very relevant anyway. >>>> >>>> This is fine for me. >>> >>> Thanks for the additional feedback! >>> >>> If I'm not mistaken (please correct me), the only remaining (hard) >>> blocker for the series would be to improve this commit message. >> >> No, you also need to fix the problem I pointed out about reg-names being >> optional on the devices you're relying on reg-names for. > > My only concern is that by marking reg-names as required we would break the ABI, You are ALREADY BREAKING the ABI. Really, for absolutely non-important cosmetic change in unit address, where I asked you repeatedly to fix the unit address, you change the ABI affecting kernel and DTS users. This is barely acceptable, but I am just annoyed already explain it to you multiple times. But now you claim, you can break ABI for cosmetic unimportant change, but actually doing something meaningful is a no-go? At least use correct arguments if you want to discuss. > since the RK3588 related changes in the binding (not the DTS ones) got already > released (i.e. since v6.17). That's also the reason we went with this deprecated > order approach. > >> The new commit >> message I am happy with, provided you also add the information Nicolas >> provided about the impact on users. > > Nicolas, can you please provide here the statement so that we can agree on the > wording? > > Thanks, > Cristian > >> >>> >>> How about the following: >>> >>> With the introduction of the RK3588 SoC, and RK3576 afterwards, three >>> register blocks have been provided for the video decoder unit instead of >>> just one, which are further referenced in the datasheet by 'link table', >>> 'function' and 'cache'. The former is present at the top of the >>> listing, starting at video decoder unit base address. >>> >>> However, while documenting RK3588, the binding broke the convention >>> expecting the unit address to indicate the start of the primary register >>> range, i.e. the 'function' block got listed before the 'link' one. >>> >>> Since the binding changes have been already released and a fix would >>> bring up an ABI break, mark the current 'reg-names' ordering as >>> deprecated and introduce an alternative 'link,function,cache' listing >>> which follows the address-based ordering according to the TRM. >>> >>> Additionally, drop the 'reg' description items as the order is not fixed >>> anymore, while the information they offer is not very relevant anyway. >>> >>> Regards, >>> Cristian > Best regards, Krzysztof