Re: [RFC v4 net-next 1/4] net: phy: add MediaTek PHY driver

From: DENG Qingfang <dqfext@gmail.com>
To: "René van Dorst" <opensource@vdorst.com>
Cc: "David S. Miller" <davem@davemloft.net>,
	Andrew Lunn <andrew@lunn.ch>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Heiner Kallweit <hkallweit1@gmail.com>,
	Jakub Kicinski <kuba@kernel.org>,
	Landen Chao <Landen.Chao@mediatek.com>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	Russell King <linux@armlinux.org.uk>,
	Sean Wang <sean.wang@mediatek.com>,
	Vivien Didelot <vivien.didelot@gmail.com>,
	Vladimir Oltean <olteanv@gmail.com>,
	Rob Herring <robh+dt@kernel.org>,
	Linus Walleij <linus.walleij@linaro.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Sergio Paracuellos <sergio.paracuellos@gmail.com>,
	linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org,
	linux-staging@lists.linux.dev, devicetree@vger.kernel.org,
	netdev@vger.kernel.org, Weijie Gao <weijie.gao@mediatek.com>,
	Chuanhong Guo <gch981213@gmail.com>,
	Frank Wunderlich <frank-w@public-files.de>,
	Thomas Gleixner <tglx@linutronix.de>,
	Marc Zyngier <maz@kernel.org>
Subject: Re: [RFC v4 net-next 1/4] net: phy: add MediaTek PHY driver
Date: Tue, 13 Apr 2021 11:59:20 +0800	[thread overview]
Message-ID: <20210413035920.1422364-1-dqfext@gmail.com> (raw)
In-Reply-To: <20210412150836.929610-1-dqfext@gmail.com>

On Mon, Apr 12, 2021 at 11:08:36PM +0800, DENG Qingfang wrote:
> On Mon, Apr 12, 2021 at 07:04:49AM +0000, René van Dorst wrote:
> > Hi Qingfang,
> > > +static void mtk_phy_config_init(struct phy_device *phydev)
> > > +{
> > > +	/* Disable EEE */
> > > +	phy_write_mmd(phydev, MDIO_MMD_AN, MDIO_AN_EEE_ADV, 0);
> > 
> > For my EEE patch I changed this line to:
> > 
> > genphy_config_eee_advert(phydev);
> > 
> > So PHY EEE part is setup properly at boot, instead enable it manual via
> > ethtool.
> > This function also takes the DTS parameters "eee-broken-xxxx" in to account
> > while
> > setting-up the PHY.
> 
> Thanks, I'm now testing with it.

Hi Rene,

Within 12 hours, I got some spontaneous link down/ups when EEE is enabled:

[16334.236233] mt7530 mdio-bus:1f wan: Link is Down
[16334.241340] br-lan: port 3(wan) entered disabled state
[16337.355988] mt7530 mdio-bus:1f wan: Link is Up - 1Gbps/Full - flow control rx/tx
[16337.363468] br-lan: port 3(wan) entered blocking state
[16337.368638] br-lan: port 3(wan) entered forwarding state

The cable is a 30m Cat.6 and never has such issue when EEE is disabled.
Perhaps WAKEUP_TIME_1000/100 or some PHY registers need to be fine-tuned,
but for now I think it should be disabled by default.

> 
> > 
> > > +
> > > +	/* Enable HW auto downshift */
> > > +	phy_modify_paged(phydev, MTK_PHY_PAGE_EXTENDED, 0x14, 0, BIT(4));