Re: [PATCH net-next 5/5] net: stmmac: support the TC9564 SoC

[Daniel Thompson <daniel@riscstar.com>]

Hi Maxime

Actually, this might be more for Alex to find when he works through the
review feedback but...


On Mon, Oct 19, 2026 at 09:52:58AM +0200, Maxime Chevallier wrote:
> > +static struct tc9564_mac_speed mac_speed[] = {
> > +	{ PHY_INTERFACE_MODE_2500BASEX,	SPEED_2500,  SP_SEL_2500BASEX },
> > +	{ PHY_INTERFACE_MODE_SGMII,	SPEED_1000,  SP_SEL_SGMII_1000M },
> > +	{ PHY_INTERFACE_MODE_SGMII,	SPEED_100,   SP_SEL_SGMII_100M },
> > +	{ PHY_INTERFACE_MODE_SGMII,	SPEED_10,    SP_SEL_SGMII_10M },
> > +};
> <snip>
> > +static int tc9564_mac_speed_select(struct tc9564_data *td,
> > +				   phy_interface_t interface, int speed)
> > +{
> > +	int i;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(mac_speed); i++) {
> > +		if (mac_speed[i].phy_interface != interface)
> > +			continue;
> > +
> > +		if (speed == mac_speed[i].speed || speed == SPEED_UNKNOWN)
> > +			return mac_speed[i].sp_sel;
> > +	}
> > +	dev_err(td->dev, "%s/%d unsupported\n", phy_modes(interface), speed);
>
> Is that "mac_speed" lookup table actually needed ? maybe a simpler switch/case
> based on the speed alone would be enough, or do we really need to validate
> the phy_interface_t each time ?

Once we add 10G PHY support I don't think it can be based on link speed
alone (for 10G PHY we have to write the same value to SP_SEL regardless
of link speed).

However even when that happens we could still code it up using switch/case
and ifs.


Daniel.