> -----Original Message----- > From: Wei Fang > Sent: 2024年8月16日 13:02 > To: Andrew Lunn <andrew@xxxxxxx> > Cc: davem@xxxxxxxxxxxxx; edumazet@xxxxxxxxxx; kuba@xxxxxxxxxx; > pabeni@xxxxxxxxxx; robh@xxxxxxxxxx; krzk+dt@xxxxxxxxxx; > conor+dt@xxxxxxxxxx; f.fainelli@xxxxxxxxx; hkallweit1@xxxxxxxxx; > linux@xxxxxxxxxxxxxxx; Andrei Botila (OSS) <andrei.botila@xxxxxxxxxxx>; > netdev@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; > linux-kernel@xxxxxxxxxxxxxxx > Subject: RE: [PATCH net-next 1/3] dt-bindings: net: tja11xx: use reverse-mode > to instead of rmii-refclk-in > > > -----Original Message----- > > From: Andrew Lunn <andrew@xxxxxxx> > > Sent: 2024年8月16日 11:28 > > To: Wei Fang <wei.fang@xxxxxxx> > > Cc: davem@xxxxxxxxxxxxx; edumazet@xxxxxxxxxx; kuba@xxxxxxxxxx; > > pabeni@xxxxxxxxxx; robh@xxxxxxxxxx; krzk+dt@xxxxxxxxxx; > > conor+dt@xxxxxxxxxx; f.fainelli@xxxxxxxxx; hkallweit1@xxxxxxxxx; > > linux@xxxxxxxxxxxxxxx; Andrei Botila (OSS) > > <andrei.botila@xxxxxxxxxxx>; netdev@xxxxxxxxxxxxxxx; > > devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx > > Subject: Re: [PATCH net-next 1/3] dt-bindings: net: tja11xx: use > > reverse-mode to instead of rmii-refclk-in > > > > > Based on the TJA data sheet, like TJA1103/TJA1104, if the reverse > > > mode is set. If XMII_MODE is set to MII, the device operates in > > > revMII mode (TXCLK and RXCLK are input). If XMII_MODE is set to > > > RMII, the device operates in revRMII mode (REF_CLK is output). So > > > it's just that the input and output directions of xx_CLK are reversed. > > > we don't need to tell the MAC to play the role of the PHY, in our > > > case, we just need the PHY to provide the reference clock in RMII mode. > > > > If this is purely about providing a reference clock, normally 25Mhz, > > there are a few PHY drivers which support this. Find one and copy it. > > There is no need to invent something new. > > > > Sorry, I didn't find the correct PHY driver, could you point me to which PHY > driver that I can refer to? > The PHY drivers I searched for using the "clk" keyword all seem to set the > clock via a vendor defined property. Such as, > realtek: "realtek,clkout-disable" > dp83867 and dp83869: "ti,clk-output-sel" and > "ti,sgmii-ref-clock-output-enable" > motorcomm: " motorcomm,tx-clk-1000-inverted" > micrel: "rmii-ref" Hi Andrew, I still cannot find a generic method in other PHY drivers to provide reference clock by PHY. So I think this patch is the best I could do, at least it's more reasonable than the "nxp,rmii-refclk-in" property.
