Re: [PATCH net 2/3] net: dsa: mt7530: move lowering TRGMII driving to mt7530_setup()

[Landen Chao (趙皎宏)]

On Mon, 2023-03-20 at 22:05 +0300, arinc9.unal@xxxxxxxxx wrote:
> 
> I asked this before, MT7530 DSA driver maintainers, please explain
> the code
> I mentioned on the second paragraph.
> 
> ---
> @@ -2207,6 +2198,15 @@ mt7530_setup(struct dsa_switch *ds)
> 
>         mt7530_pll_setup(priv);
> 
> +       /* Lower Tx driving for TRGMII path */
> +       for (i = 0; i < NUM_TRGMII_CTRL; i++)
> +               mt7530_write(priv, MT7530_TRGMII_TD_ODT(i),
> +                            TD_DM_DRVP(8) | TD_DM_DRVN(8));
> +
I guess you ask this part, and I try my best to recall what the
original author said years ago.
It is used to adjust the RX delay of port 6 to match the tx
signal of the link partner.
> +       for (i = 0; i < NUM_TRGMII_CTRL; i++)
> +               mt7530_rmw(priv, MT7530_TRGMII_RD(i),
> +                          RD_TAP_MASK, RD_TAP(16));
> +
> 
>