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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7E1AFEF48E8 for ; Fri, 13 Feb 2026 08:17:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Jz7vtUwnkx90fQXLmbBVcLdhqYtGqJ/IOHriRInnSbM=; b=lyRh2UwzzGaeAY1x0ALvBCXUBD djwlGP/JRTofx75h2QSnGOXHbkG+N6xMaiMwt80C9Opt9m9JZWAxAKN7SLPbYQ+BizTr9OecZ9mg/ y6rLfeyecRW5saOjbcn0m1kQL7JFAlqFLZnjmg3OoN+NLaj+ekUbo2+Fvadt1PrFdY1A8se+udZ5m Ss2xgmgTDOvYkIPtgagm+CmLRfC+WNUcSbvDTqH2VKEfdtdA+rkOowgCPtr8pSsxomONYAA0FR0vA GlhxZLZ6K4A6CRK175voC7eD3/Svx+5gKTLkKEK+4bZMxjXMhiITR+AwG+LHjse1tELvLBlIr71BR j8+cykGA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vqoMM-000000039ey-2dKg; Fri, 13 Feb 2026 08:17:06 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vqoMK-000000039ei-2elp; Fri, 13 Feb 2026 08:17:04 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 049546001A; Fri, 13 Feb 2026 08:17:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9CB68C116C6; Fri, 13 Feb 2026 08:17:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770970623; bh=hbYAQt6TNDZ/qXSwhJHkgExQTtHCoS7ggq1824ovTnU=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=sz+4oPuwy6Y0e3rrzOZBPH52OtlvC18v6Q17Tg/0qckunMalGdoOMAKPS5BvhWe0t E4XmiXd7zeq3gP8n6EJbjnWlMIh/kcAmlTPfX1oViwtfCtJkPYHif3MKg87/BnLhmn H0lo1MtX65GWK640lVwPj32jkNsBZb1TkxlNoFuOgpIT5swr6mWpIZBgSc6aNR+YOU zNJ1WZJ5nLj/JBh7IzaM6ILk7wvcEfk+q3CvzLjGl8zbLmMndKlw3RAOBoTtlhCWsI flAX+O9Cxh9tBV18rzv2V8XYRTUvbPKPlBZU8lnpl1TiiZVMQaIh6L/nNjh/GuA3x0 kti5SGsXOxbmg== Message-ID: <2f68ee18-e9d9-4da6-900c-93a7663b3c9d@kernel.org> Date: Fri, 13 Feb 2026 09:16:58 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RFC v4 1/4] media: dt-bindings: Add Amlogic V4L2 video decoder To: Zhentao Guo , Mauro Carvalho Chehab , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Neil Armstrong , Kevin Hilman , Jerome Brunet , Martin Blumenstingl Cc: linux-media@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-amlogic@lists.infradead.org References: <20260213-b4-s4-vdec-upstream-v4-0-c7112d00d662@amlogic.com> <20260213-b4-s4-vdec-upstream-v4-1-c7112d00d662@amlogic.com> <75e55ceb-e6dd-47b5-a829-66f6fbb3e13e@amlogic.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: <75e55ceb-e6dd-47b5-a829-66f6fbb3e13e@amlogic.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 13/02/2026 09:02, Zhentao Guo wrote: > Hi Krzysztof, > > > 在 2026/2/13 15:35, Krzysztof Kozlowski 写道: >> [ EXTERNAL EMAIL ] >> >> On 13/02/2026 06:12, Zhentao Guo via B4 Relay wrote: >>> From: Zhentao Guo >>> >>> Describe the initial support for the V4L2 stateless video decoder >>> driver used with the Amlogic S4 (S805X2) platform. >>> >>> Signed-off-by: Zhentao Guo >>> --- >>> .../bindings/media/amlogic,s4-vcodec-dec.yaml | 96 ++++++++++++++++++++++ >>> 1 file changed, 96 insertions(+) >>> >>> diff --git a/Documentation/devicetree/bindings/media/amlogic,s4-vcodec-dec.yaml b/Documentation/devicetree/bindings/media/amlogic,s4-vcodec-dec.yaml >>> new file mode 100644 >>> index 000000000000..88780514d06c >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/media/amlogic,s4-vcodec-dec.yaml >>> @@ -0,0 +1,96 @@ >>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) >>> +# Copyright (C) 2025 Amlogic, Inc. All rights reserved >>> +%YAML 1.2 >>> +--- >>> +$id:http://devicetree.org/schemas/media/amlogic,s4-vcodec-dec.yaml# >>> +$schema:http://devicetree.org/meta-schemas/core.yaml# >>> + >>> +title: Amlogic Video Decode Accelerator >>> + >>> +maintainers: >>> + - Zhentao Guo >>> + >>> +description: >>> + The Video Decoder Accelerator present on Amlogic SOCs. >>> + It supports stateless h264 decoding. >>> + >>> +properties: >>> + compatible: >>> + const: amlogic,s4-vcodec-dec >> Why do you repeat "dec" twice? codec means decoder, so what is the last >> "dec" about? > In fact, codec means encoder+decoder, and dec is short for decoder. Yes, that's what I meant, so why do you repeat decoder? >>> + >>> + reg: >>> + maxItems: 2 >>> + >>> + reg-names: >>> + items: >>> + - const: dos >>> + - const: dmc >>> + >>> + interrupts: >>> + maxItems: 3 >>> + >>> + clocks: >>> + maxItems: 3 >>> + >>> + clock-names: >>> + items: >>> + - const: vdec >>> + - const: clk_vdec_mux >>> + - const: clk_hevcf_mux >> Name them based on their role/name in this device. Why this device would >> care that it receives a mux? Not a div? or not a gate? > Ok, previously we overlooked this. We will improve it in the next version. >>> + >>> + power-domains: >>> + maxItems: 2 >>> + >>> + power-domain-names: >>> + items: >>> + - const: vdec >>> + - const: hevc >>> + >>> + resets: >>> + maxItems: 1 >>> + >>> + amlogic,canvas: >>> + description: should point to a canvas provider node >> Why? What for? >> >> What is canvas provider? > > The canvas provider is: drivers/soc/amlogic/meson-canvas.c What is this "canvas" device. > > In short, canvas is a hardware IP inside the Amlogic SoC. The decoder IP > needs to access DDR through canvas IP, so we need to reference the Why decoder cannot access DDR directly? Best regards, Krzysztof