Re: [PATCH v5 10/10] net: stmmac: dwmac-sun8i: Handle integrated/external MDIOs

From: Andrew Lunn
Date: Fri Sep 08 2017 - 10:00:34 EST


> > > +static int mdio_mux_syscon_switch_fn(int current_child, int desired_child,
> > > + void *data)
> > > +{
> > > + struct stmmac_priv *priv = data;
> > > + struct sunxi_priv_data *gmac = priv->plat->bsp_priv;
> > > + u32 reg, val;
> > > + int ret = 0;
> > > + bool need_reset = false;
> > > +
> > > + if (current_child ^ desired_child) {
> > > + regmap_read(gmac->regmap, SYSCON_EMAC_REG, &reg);
> > > + switch (desired_child) {
> > > + case DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID:
> > > + dev_info(priv->device, "Switch mux to internal PHY");
> > > + val = (reg & ~H3_EPHY_MUX_MASK) | H3_EPHY_SELECT;
> > > + if (gmac->use_internal_phy)
> > > + need_reset = true;
> > > + break;
> >
> > This i don't get. Why do you need use_internal_phy? Isn't that
> > implicit from DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID? Is it even possible to
> > use an external PHY on the internal MDIO bus?
> >
>
> On my H3 box with external PHY, the MDIO mux library first select (for scan ?) the internal MDIO.
> Without use_internal_phy usage, this board will launch a reset to use the internal MDIO... and this reset timeout/fail.

Do you know why the reset times out/fails?

Andrew