回覆: 回覆: [PATCH net-next v5 1/7] dt-bindings: net: ftgmac100: Make Aspeed compatibles standalone

[Jacky Chou]

> > > > The aspeed,ast2400-mac, aspeed,ast2500-mac, and aspeed,ast2600-mac
> > > > compatibles are currently only valid when paired with the generic
> > > > "faraday,ftgmac100" fallback: if a node ever bound through the
> > > > generic entry alone, ftgmac100_probe() would set
> > > > rxdes0_edorr_mask/txdes0_edotr_mask to BIT(15) instead of the
> > > > Aspeed BIT(30), skip Aspeed clock setup, and leave the DMA mask too
> narrow.
> > >
> > > And device would work or not? If device still works after all these
> > > steps above, then why isn't fallback applicable?
> > >
> > > Be explicit, because I have no clue whether Aspeed clock setup is
> > > necessary for device to operate.
> > >
> >
> > It is necessary: ftgmac100_setup_clk() enables the MAC's clock, and
> > only runs when priv->is_aspeed is true - skipped if a node ever bound
> > through the generic entry. Without ftgmac100_setup_clk(), the MAC on
> 
> This part is obvious.
> 
> > Aspeed platform would be left without a working clock, so it wouldn't
> > be able to configure register and TX/RX at all.
> 
> So you are saying device will not work? Then make it obvious that clock is
> necessary for basic register access.
> 

Yes, the MAC on Aspeed platform does not work at all. Without the clock, even basic register
access to the MAC is not possible.

Thanks,
Jacky