Received-SPF: pass (google.com: domain of linux-kernel+bounces-127440-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
Message-ID: <5805e6e7-76a4-4a0f-abd0-823aed023daf@foss.st.com>
Date: Tue, 2 Apr 2024 08:23:23 +0200
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH v5 1/1] dt-bindings: net: dwmac: Document STM32 property
 st,ext-phyclk
Content-Language: en-US
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        "David S . Miller"
	<davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>, Jakub Kicinski
	<kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, Rob Herring
	<robh+dt@kernel.org>,
        Krzysztof Kozlowski
	<krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Alexandre Torgue
	<alexandre.torgue@foss.st.com>,
        Richard Cochran <richardcochran@gmail.com>,
        Jose Abreu <joabreu@synopsys.com>, Liam Girdwood <lgirdwood@gmail.com>,
        Mark
 Brown <broonie@kernel.org>, Marek Vasut <marex@denx.de>
CC: <netdev@vger.kernel.org>, <devicetree@vger.kernel.org>,
        <linux-stm32@st-md-mailman.stormreply.com>,
        <linux-arm-kernel@lists.infradead.org>, <linux-kernel@vger.kernel.org>
References: <20240328140803.324141-1-christophe.roullier@foss.st.com>
 <20240328140803.324141-2-christophe.roullier@foss.st.com>
 <46b065d1-82d7-4a15-9de2-1e0bdd2a9085@linaro.org>
From: Christophe ROULLIER <christophe.roullier@foss.st.com>
In-Reply-To: <46b065d1-82d7-4a15-9de2-1e0bdd2a9085@linaro.org>
Content-Type: text/plain; charset="UTF-8"; format=flowed
Content-Transfer-Encoding: 7bit


On 3/30/24 19:40, Krzysztof Kozlowski wrote:
> On 28/03/2024 15:08, Christophe Roullier wrote:
>> The Linux kernel dwmac-stm32 driver currently supports three DT
>> properties used to configure whether PHY clock are generated by
>> the MAC or supplied to the MAC from the PHY.
>>
>> Originally there were two properties, st,eth-clk-sel and
>> st,eth-ref-clk-sel, each used to configure MAC clocking in
>> different bus mode and for different MAC clock frequency.
>> Since it is possible to determine the MAC 'eth-ck' clock
>> frequency from the clock subsystem and PHY bus mode from
>> the 'phy-mode' property, two disparate DT properties are
>> no longer required to configure MAC clocking.
>>
>> Linux kernel commit 1bb694e20839 ("net: ethernet: stmmac: simplify phy modes management for stm32")
>> introduced a third, unified, property st,ext-phyclk. This property
>> covers both use cases of st,eth-clk-sel and st,eth-ref-clk-sel DT
>> properties, as well as a new use case for 25 MHz clock generated
>> by the MAC.
>>
>> The third property st,ext-phyclk is so far undocumented,
>> document it.
>>
>> Below table summarizes the clock requirement and clock sources for
>> supported PHY interface modes.
>>   __________________________________________________________________________
>> |PHY_MODE | Normal | PHY wo crystal|   PHY wo crystal   |No 125Mhz from PHY|
>> |         |        |      25MHz    |        50MHz       |                  |
>>
>> ---------------------------------------------------------------------------
>> |  MII    |    -   |     eth-ck    |        n/a         |       n/a        |
>> |         |        | st,ext-phyclk |                    |                  |
>>
>> ---------------------------------------------------------------------------
>> |  GMII   |    -   |     eth-ck    |        n/a         |       n/a        |
>> |         |        | st,ext-phyclk |                    |                  |
>>
>> ---------------------------------------------------------------------------
>> | RGMII   |    -   |     eth-ck    |        n/a         |      eth-ck      |
>> |         |        | st,ext-phyclk |                    | st,eth-clk-sel or|
>> |         |        |               |                    | st,ext-phyclk    |
>>
>> ---------------------------------------------------------------------------
>> | RMII    |    -   |     eth-ck    |      eth-ck        |       n/a        |
>> |         |        | st,ext-phyclk | st,eth-ref-clk-sel |                  |
>> |         |        |               | or st,ext-phyclk   |                  |
>>
>> ---------------------------------------------------------------------------
>>
>> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>> Signed-off-by: Christophe Roullier <christophe.roullier@foss.st.com>
> Can you please start testing patches *before* sending them?
Yes sorry, when I removed patch with phy-supply property (1/2), I had 
conflict merge and I did not pay attention that my commit was modified :-(
>
> Best regards,
> Krzysztof
>