From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 0387C111BA; Tue, 31 Oct 2023 11:01:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="Ut52fJKP" Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DDBA4A6; Tue, 31 Oct 2023 04:01:05 -0700 (PDT) Received: from [100.116.17.117] (cola.collaboradmins.com [195.201.22.229]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: cristicc) by madras.collabora.co.uk (Postfix) with ESMTPSA id 357F766073A4; Tue, 31 Oct 2023 11:01:02 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1698750064; bh=7i4L1gq9GTQdB9bIM1L/ajdeUm7F+CvMd9bg+rP0cDY=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=Ut52fJKPN1zfqlv6rUpMovwC7ndfxzSTZs7G3NPsVQFCGhKFXlA8Ka//XbDcXfPf5 NWRV3qXXXV3NFtYoJHJEz44vaWYtmUGOK4YAQPTl6Br5B/UjpEqlVtaaWjQdeZAxli 9YwX0zOsUIPSPJ9hEI80CMqOsobA+55TBDZakhPKwInf5DjkcxUgWQC67UcVXXfzWL mF3I24QkTAvlie/uYqlZtG7mPDzLKulDUspn2b4NnFS/CUC0yEqMEaSOIahs3BSARQ Rzv1ciPJ1Dr0tr/GXXJFk1dbo2Crq62HeM7cFU4W8nQ2SoQV+MyXL2TNKk8x269C4R uJPUqBNrpfsww== Message-ID: Date: Tue, 31 Oct 2023 13:00:59 +0200 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 v2 01/12] dt-bindings: net: snps,dwmac: Allow exclusive usage of ahb reset Content-Language: en-US To: Krzysztof Kozlowski , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Emil Renner Berthing , Samin Guo , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Torgue , Jose Abreu , Maxime Coquelin , Richard Cochran , Giuseppe Cavallaro Cc: netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, kernel@collabora.com References: <20231029042712.520010-1-cristian.ciocaltea@collabora.com> <20231029042712.520010-2-cristian.ciocaltea@collabora.com> <3016eff2-fce5-4b5e-bbb2-d56cbb45df85@linaro.org> <05186c62-fcad-4d56-8ae8-d802f87a39e2@collabora.com> <98d90ba9-7e69-4b54-830d-bdbc0e6c54fe@linaro.org> From: Cristian Ciocaltea In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/31/23 07:48, Krzysztof Kozlowski wrote: > On 30/10/2023 20:07, Cristian Ciocaltea wrote: >> On 10/30/23 09:26, Krzysztof Kozlowski wrote: >>> On 29/10/2023 23:24, Cristian Ciocaltea wrote: >>>> On 10/29/23 13:25, Krzysztof Kozlowski wrote: >>>>> On 29/10/2023 05:27, Cristian Ciocaltea wrote: >>>>>> The Synopsys DesignWare MAC found on the StarFive JH7100 SoC requires >>>>>> just the 'ahb' reset name, but the binding allows selecting it only in >>>>>> conjunction with 'stmmaceth'. >>>>>> >>>>>> Fix the issue by permitting exclusive usage of the 'ahb' reset name. >>>>>> >>>>>> Signed-off-by: Cristian Ciocaltea >>>>>> --- >>>>>> Documentation/devicetree/bindings/net/snps,dwmac.yaml | 2 +- >>>>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>>>> >>>>>> diff --git a/Documentation/devicetree/bindings/net/snps,dwmac.yaml b/Documentation/devicetree/bindings/net/snps,dwmac.yaml >>>>>> index 5c2769dc689a..a4d7172ea701 100644 >>>>>> --- a/Documentation/devicetree/bindings/net/snps,dwmac.yaml >>>>>> +++ b/Documentation/devicetree/bindings/net/snps,dwmac.yaml >>>>>> @@ -146,7 +146,7 @@ properties: >>>>>> reset-names: >>>>>> minItems: 1 >>>>>> items: >>>>>> - - const: stmmaceth >>>>>> + - enum: [stmmaceth, ahb] >>>>> >>>>> Also, this makes sense only with patch #4, so this should be squashed there. >>>> >>>> I added this as a separate patch since it changes the generic schema >>>> which is included by many other bindings. JH7100 just happens to be the >>>> first use-case requiring this update. But I can squash the patch if >>>> that's not a good enough reason to keep it separately. >>> >>> If there is no single user of this, why changing this? I would even >>> argue that it is not correct from existing bindings point of view - >>> nothing allows and uses ahb as the only reset. Even the commit msg >>> mentions your hardware from patch 4. >> >> Sorry, I'm not sure I follow. JH7100 is (or will be) the user of it and, >> as a matter of fact, something similar has been done recently while >> adding support for JH7110. > > Every patch should stand on its own and at this point nothing uses it. > We apply this patch #1 and we add dead code, unused case. > >> >> In particular, commit [1] changed this binding before the JH7110 >> compatible was introduced in a subsequent patch. On a closer look that >> commit made a statement which is not entirely correct: >> >> "dwmac controller may require one (stmmaceth) or two (stmmaceth+ahb) >> reset signals" >> >> That's because stmmaceth is also optional in dwmac's driver, hence the >> correct message would have been: >> >> "[...] may require one (stmmaceth OR ahb) [...]" > > Driver does not describe the hardware. The bindings do, so according to > that description all supported hardware required MAC reset (stmmaceth). > Otherwise please point me to any hardware which skips MAC reset and > requires AHB reset instead (not future hardware, but current). I might have found one (arch/arm/boot/dts/allwinner/sun6i-a31.dtsi): gmac: ethernet@1c30000 { compatible = "allwinner,sun7i-a20-gmac"; [...] resets = <&ccu RST_AHB1_EMAC>; reset-names = "stmmaceth"; [...] }; It's possible the 'stmmaceth' naming has been used instead of 'ahb' just to avoid updating the binding, but that's just an assumption looking at RST_AHB1_EMAC. I will proceed with the squash for v3. Thanks for clarifying, Cristian