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Message-ID: <6f97e753-435e-4b86-bd47-290097f6a3f0@quicinc.com>
Date: Tue, 9 Jan 2024 20:22:40 +0530
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Subject: Re: [PATCH v2] net: stmmac: dwmac-qcom-ethqos: Add support for 2.5G
 SGMII
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To: Andrew Lunn <andrew@lunn.ch>
CC: Vinod Koul <vkoul@kernel.org>, Bhupesh Sharma <bhupesh.sharma@linaro.org>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Jose Abreu
	<joabreu@synopsys.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet
	<edumazet@google.com>, Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni
	<pabeni@redhat.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>, <netdev@vger.kernel.org>,
        <linux-arm-msm@vger.kernel.org>,
        <linux-stm32@st-md-mailman.stormreply.com>,
        <linux-arm-kernel@lists.infradead.org>, <linux-kernel@vger.kernel.org>,
        <kernel@quicinc.com>, Andrew Halaney <ahalaney@redhat.com>
References: <20240108121128.30071-1-quic_snehshah@quicinc.com>
 <4216bcbb-730d-4c51-a9ce-d3f0a0846e31@lunn.ch>
From: Sneh Shah <quic_snehshah@quicinc.com>
In-Reply-To: <4216bcbb-730d-4c51-a9ce-d3f0a0846e31@lunn.ch>
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On 1/9/2024 1:00 AM, Andrew Lunn wrote:
> On Mon, Jan 08, 2024 at 05:41:28PM +0530, Sneh Shah wrote:
>> Serdes phy needs to operate at 2500 mode for 2.5G speed and 1000
>> mode for 1G/100M/10M speed.
>> Added changes to configure serdes phy and mac based on link speed.
> 
> Please take a look at:
> 
> https://www.kernel.org/doc/html/next/process/maintainer-netdev.html
> 
> The Subject is missing which tree this is for. Also, net-next is
> closed at the moment.

It was supposed to be net-next. Missed updating in subject.
Sorry for that!
If net-next is closed at the moment, how to proceed further?
Should I wait until it gets reopened?
> 
>>  	switch (ethqos->speed) {
>> +	case SPEED_2500:
>> +		val &= ~ETHQOS_MAC_CTRL_PORT_SEL;
>> +		rgmii_updatel(ethqos, RGMII_CONFIG2_RGMII_CLK_SEL_CFG,
>> +			      RGMII_CONFIG2_RGMII_CLK_SEL_CFG,
>> +			      RGMII_IO_MACRO_CONFIG2);
>> +		if (ethqos->serdes_speed != SPEED_2500)
>> +			phy_set_speed(ethqos->serdes_phy, SPEED_2500);
> 
> Is calling phy_set_speed() expensive? Why not just unconditionally
> call it?
> 
It reconfigures whole serdes phy block, with lots of register read/writes.
So I feel it is better to avoid doing this unconditionally
>      Andrew