Re: [PATCH] net: phy: at803x: disable delay only for RGMII mode

From: Vinod Koul <vkoul@kernel.org>
To: Peter Ujfalusi <peter.ujfalusi@ti.com>
Cc: David S Miller <davem@davemloft.net>,
	linux-arm-msm@vger.kernel.org,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	netdev@vger.kernel.org, Niklas Cassel <niklas.cassel@linaro.org>,
	Andrew Lunn <andrew@lunn.ch>,
	Florian Fainelli <f.fainelli@gmail.com>,
	"Nori, Sekhar" <nsekhar@ti.com>,
	Marc Gonzalez <marc.w.gonzalez@free.fr>
Subject: Re: [PATCH] net: phy: at803x: disable delay only for RGMII mode
Date: Fri, 15 Feb 2019 15:46:12 +0530	[thread overview]
Message-ID: <20190215101612.GF21884@vkoul-mobl> (raw)
In-Reply-To: <89c39811-b100-564a-da40-abf46e450c95@ti.com>

On 13-02-19, 09:02, Peter Ujfalusi wrote:
> Hi Vinod,
> 
> On 12/02/2019 16.19, Vinod Koul wrote:
> > Per "Documentation/devicetree/bindings/net/ethernet.txt" RGMII mode
> > should not have delay in PHY whereas RGMII_ID and RGMII_RXID/RGMII_TXID
> > can have delay in phy.
> > 
> > So disable the delay only for RGMII mode and disable for other modes
> s/disable for other modes/enable for other modes

oops

> 
> Works fine on am335x-evmsk:
> Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>

Thanks for quick testing..

> 
> and few comment
> 
> > Fixes: cd28d1d6e52e: ("net: phy: at803x: Disable phy delay for RGMII mode")
> > Reported-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
> > Signed-off-by: Vinod Koul <vkoul@kernel.org>
> > ---
> >  drivers/net/phy/at803x.c | 33 ++++++++++++++++++++++++++-------
> >  1 file changed, 26 insertions(+), 7 deletions(-)
> > 
> > diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
> > index 8ff12938ab47..7b54b54e3316 100644
> > --- a/drivers/net/phy/at803x.c
> > +++ b/drivers/net/phy/at803x.c
> > @@ -110,6 +110,18 @@ static int at803x_debug_reg_mask(struct phy_device *phydev, u16 reg,
> >  	return phy_write(phydev, AT803X_DEBUG_DATA, val);
> >  }
> >  
> > +static inline int at803x_enable_rx_delay(struct phy_device *phydev)
> > +{
> > +	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0, 0,
> > +				     AT803X_DEBUG_RX_CLK_DLY_EN);
> > +}
> 
> static inline int at803x_select_rx_delay(struct phy_device *phydev,
> 					 bool enable)
> {
> }
> 
> > +
> > +static inline int at803x_enable_tx_delay(struct phy_device *phydev)
> > +{
> > +	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_5, 0,
> > +				     AT803X_DEBUG_TX_CLK_DLY_EN);
> > +}
> 
> static inline int at803x_select_tx_delay(struct phy_device *phydev,
> 					 bool enable)
> {
> }
> 
> perhaps?

Given that we would again branch off on enable, I see this as no better
case so I will keep existing

> 
> > +
> >  static inline int at803x_disable_rx_delay(struct phy_device *phydev)
> >  {
> >  	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
> > @@ -255,18 +267,25 @@ static int at803x_config_init(struct phy_device *phydev)
> >  	if (ret < 0)
> >  		return ret;
> >  
> > -	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID ||
> > -			phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
> > -			phydev->interface == PHY_INTERFACE_MODE_RGMII) {
> > +	if (phydev->interface == PHY_INTERFACE_MODE_RGMII) {
> >  		ret = at803x_disable_rx_delay(phydev);
> >  		if (ret < 0)
> >  			return ret;
> > +		ret = at803x_disable_tx_delay(phydev);
> > +		if (ret < 0)
> > +			return ret;
> 
> is it a possibility to have PHY_INTERFACE_MODE_RGMII and other RGMII_ID
> || RGMII_TXID || RGMII_RXID set at the same time?

Nope that would not make sense

> if not you can just return from here, no need to check for other RGMII
> modes?

for RGMII yes indeed..

-- 
~Vinod