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 AB0A63FF1; Sun, 24 Aug 2025 10:27:01 +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=1756031221; cv=none; b=nlDm9YrmVTfZcLZ4e61ZvlI/yCzOt8d34ke4LdUV+kJ9pWjw70jhjFgCDSadkGPN+Rtq9Ffjy7Vqoro83MQTriAmdCf3i+OkTd/x5pwDkJC3q4ZQ8qwxZyaRGUB2rcnnT4/hwkCdO3/tsddMi6mANHlLDlk/dT0gdX+tvKK4fbc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756031221; c=relaxed/simple; bh=2fFxf047dZ/bxH4koaGiZYykN/ur/aYx1D1ION5XVOc=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=jx5UbCfE97dXL1qO/Nw8NvuRisqDX3NkYns+no/TAMtGwWDPl3UtDDzpORBW2bn5PwR2uFuzOOxdJ/isjIAc3m4G5w/jEhoqMBmai0XHSgt3gDmH/Ske0d7kaVIAMrOOdbLm9MzE6kkuElUgVycdEydTiK19GRYGT7XTu0DEkts= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TysKFbNG; 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="TysKFbNG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6141EC4CEEB; Sun, 24 Aug 2025 10:26:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756031221; bh=2fFxf047dZ/bxH4koaGiZYykN/ur/aYx1D1ION5XVOc=; h=Date:Subject:To:References:From:In-Reply-To:From; b=TysKFbNG5j5fN/aVTQlhPJ6ATcYT5e4wK+s+ZeK7bcz3tKBbw9HOzhwF1EWPCa++V GfnaR7363aaewlMy9OfNfMIMwP5rXjssBaVcgeNBdylNCdh4DpH2npt9ltIpRpK1LP jaRxfL1b/2ywPRAg8nLAFRkq1J8FEl2AhbV0tneaZ8F9N9QEWOLf1Hq7gkfPK13g2Y c1/+FJYV/4txaspZmsunP5nif/Lqin0m25nNFSzzzKdFJ/r4TNmpyBEOtBQwPxkTUf fbyz879zFzGaVHwTz5UZVRFW6XvWDIsTXvG2zdVGDbH9YEdMMxukKGVL1IFi1pbfJq 7YJ8MWzSG9YAw== Message-ID: <5c7f78ae-01d8-40e3-a370-76953921ade9@kernel.org> Date: Sun, 24 Aug 2025 12:26:56 +0200 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 v2 1/3] dt-bindings: lgm-dma: Added intel,dma-sw-desc property. To: Yi xin Zhu , "vkoul@kernel.org" , "robh@kernel.org" , "krzk+dt@kernel.org" , "conor+dt@kernel.org" , "p.zabel@pengutronix.de" , "kees@kernel.org" , "dave.jiang@intel.com" , "av2082000@gmail.com" , "dmaengine@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" References: <20250808032243.3796335-1-yzhu@maxlinear.com> <32a2ec88-b9b8-4c4d-9836-838702e4e136@kernel.org> <1826bd7a-621d-49d0-b6ff-7ff723ec9f2c@kernel.org> 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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 18/08/2025 10:41, Yi xin Zhu wrote: > Hi Krzysztof, > > On 15/08/2025 18:40, Krzysztof wrote: >> >> >> What is a "SoC level configuration"? >> >> From your explanation 1+2 it feels like consumer chooses it. Where is a full DTS >> showing all this? >> >> >>> of the DMA instances work in hardware descriptor mode while other DMA >>> instances work in software descriptor mode or all in HW/SW mode. >>> >> >> Best regards, >> Krzysztof > > In the LGM SoC, The DMA instances are default connected to CBM(central buffer manager) to automate the DMA descriptors. > It can also be detached from CBM to use it in different use cases individually. > > In the HW descriptor case, the device tree would be like: > > dma1tx: dma-controller@e7300000 { > compatible = "intel,lgm-dma1tx"; > reg = <0xe7300000 0x1000>; > ... > #dma-cells = <3>; > intel,dma-poll-cnt = <16>; > }; > > cbm: cbm@e1000000 { > dmas = <&dma1tx 0 0 64>, <&dma1tx 1 0 64> ... <&dma1tx 15 0 64>; > > }; > > DMA HW feature, desc_fod(descriptor fetch on demand) and desc_in_sram are turned on in the DMA controller in this case. > These HW features are defined in platform data in the existing DMA driver as default enabled. > static const struct ldma_inst_data dma1tx = { > ... > .desc_fod = true; > .desc_in_sram = true; > }; > > In the SW descriptor management case, the device tree would be like: > > dma1tx: dma-controller@e7300000 { > compatible = "intel,lgm-dma1tx"; > reg = <0xe7300000 0x1000>; > ... > #dma-cells = <3>; > intel,dma-poll-cnt = <16>; > intel,dma-sw-desc; That's then implied by compatible, no? If you disagree, please post complete upstream DTS. Best regards, Krzysztof