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 3C85E2AD3D; Sun, 3 Aug 2025 09:21:04 +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=1754212865; cv=none; b=b2UybWkUNW/LXMFYQua08spj9gnSSkOyRhLPE66PSkkWRz7Yii1pUPuEF0WnkDCUKhTP5pouhHoIUF0X5t3rEGD4ESja6V/fQPIUafpIDG/vTQnjXXmvOPKPkQBqxcTo+bv1a8ggjBuBCi/1HrLsY2deZUd7aUn1OgJWZ6UhqvA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754212865; c=relaxed/simple; bh=6SiqmzgUPZiU3wRacVGyFYA2GVYo9ShBH5POmw4XLeQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=IDixJWpfR2O4hsV3/PC2VeXjiLatlu4cHPXuHyghAcrrT/e1SSMge6oarIz/Ij5xx5vAt4Y+ZXa1qUtPhFd2SOUOckxRMc9EnnNAdr6yO9SUjH5cr5bm4u8sgcpUnolWNoTxZsYpvOGkibE8BAFQ0fDyZ59CBzfiWBOZ0xF9Wfg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=aw/j3Oeq; 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="aw/j3Oeq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EBF17C4CEF8; Sun, 3 Aug 2025 09:21:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1754212864; bh=6SiqmzgUPZiU3wRacVGyFYA2GVYo9ShBH5POmw4XLeQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=aw/j3OeqjQ/iFCgHi/RWGqYq7syYaTdWk/XyaeXaSWa/9B/gULAeCtn3X6d553UIT zis3vGT82aTx9/lCXCvzYcBu6UkuBARnGc3HWPN89gcd5+5AKhF/uOjCtMv7xIGNf+ 6nr3x9rSCH6NIZ4Zu9h/+pq+ejCwjM6eVVraXwfbPEkoX4ERw9PLA5qrzxuXeZId1k jizU6mOr5TVMPndjKUw94sL3dLiBKouEb3aDrUpApjcD3ItpNOso2S1yhNL+lSnWJr /QYUSABbIQBwuVFEwEhHlWDn0e8liZTWYDl0K1HOfCZA1XFM6u1z8TXQGIN2fS1Uec EZfHP5PhhuURA== Message-ID: <00f6d696-a8d2-41a5-819a-dc1ed87d35bb@kernel.org> Date: Sun, 3 Aug 2025 11:20:59 +0200 Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next v2 1/3] dt-bindings: sram: qcom,imem: Allow modem-tables To: Konrad Dybcio , Konrad Dybcio , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Bjorn Andersson , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alex Elder Cc: Marijn Suijten , linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Alex Elder References: <20250527-topic-ipa_imem-v2-0-6d1aad91b841@oss.qualcomm.com> <20250527-topic-ipa_imem-v2-1-6d1aad91b841@oss.qualcomm.com> <97724a4d-fad5-4e98-b415-985e5f19f911@kernel.org> <68622599-02d0-45ca-82f5-cf321c153cde@kernel.org> <62b0f514-a8a9-4147-a5c0-da9dbe13ce39@kernel.org> <747e5221-0fb1-4081-9e98-94b330ebf8c7@oss.qualcomm.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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 31/07/2025 11:47, Konrad Dybcio wrote: > On 7/30/25 3:14 PM, Krzysztof Kozlowski wrote: >> On 30/07/2025 14:07, Konrad Dybcio wrote: >>>>>>>> >>>>>>>> Missing additionalProperties: false, which would point you that this is >>>>>>>> incomplete (or useless because empty). >>>>>>> >>>>>>> How do I describe a 'stupid' node that is just a reg? >>>>>> With "reg" - similarly to many syscon bindings. >>>>> >>>>> Is this sort of inline style acceptable, or should I introduce >>>>> a separate file? >>>> >>>> It's fine, assuming that it is desired in general. We do not describe >>>> individual memory regions of syscon nodes and this is a syscon. >>>> >>>> If this is NVMEM (which it looks like), then could use NVMEM bindings to >>>> describe its cells - individual regions. But otherwise we just don't. >>> >>> It's volatile on-chip memory >>> >>>> There are many exceptions in other platforms, mostly old or even >>>> unreviewed by DT maintainers, so they are not a recommended example. >>>> >>>> This would need serious justification WHY you need to describe the >>>> child. Why phandle to the main node is not enough for consumers. >>> >>> It's simply a region of the SRAM, which needs to be IOMMU-mapped in a >>> specific manner (should IMEM move away from syscon+simple-mfd to >>> mmio-sram?). Describing slices is the DT way to pass them (like under >>> NVMEM providers). >> >> >> Then this might be not a syscon, IMO. I don't think mixing syscon and >> SRAM is appropriate, even though Linux could treat it very similar. >> >> syscon is for registers. mmio-sram is for SRAM or other parts of >> non-volatile RAM. >> >> Indeed you might need to move towards mmio-sram. >> >>> >>>> >>>> If the reason is - to instantiate child device driver - then as well no. >>>> This has been NAKed on the lists many times - you need resources if the >>>> child should be a separate node. Address space is one resource but not >>>> enough, because it can easily be obtained from the parent/main node. >>> >>> There is no additional driver for this >> >> Then it is not a simple-mfd... > > Indeed it's really not > > I found out however that the computer history museum (i.e. > qcom-apq8064-asus-nexus7-flo.dts and qcom-msm8974.dtsi) seems to > have used simple-mfd, so that the subnode (syscon-reboot-mode) is > matched against a driver > > The same can be achieved if we stick an of_platform_populate() at > the end of mmio-sram probe - thoughts? You cannot (or should not) remove simple-mfd from existing binding. But the point is that the list should not grow. Maybe the binding should receive a comment next to compatible: " # Do not grow this, if you add here new compatible, you agree to buy round of drinks on next LPC to all upstream maintainers" ? Best regards, Krzysztof