Re: [PATCH net-next 1/2] net: stmmac: enable 2.5Gbps link speed
From: Andrew Lunn <andrew@lunn.ch>
Date: 2021-04-02 12:35:22
Also in:
linux-arm-kernel, lkml
On Fri, Apr 02, 2021 at 07:45:04AM +0000, Voon, Weifeng wrote:
quoted
quoted
+ /* 2.5G mode only support 2500baseT full duplex only */ + if (priv->plat->has_gmac4 && priv->plat->speed_2500_en) { + phylink_set(mac_supported, 2500baseT_Full); + phylink_set(mask, 10baseT_Half); + phylink_set(mask, 10baseT_Full); + phylink_set(mask, 100baseT_Half); + phylink_set(mask, 100baseT_Full); + phylink_set(mask, 1000baseT_Half); + phylink_set(mask, 1000baseT_Full); + phylink_set(mask, 1000baseKX_Full);Why? This seems at odds to the comment above?quoted
What about 2500baseX_Full ?The comments explain that the PCS<->PHY link is in 2500BASE-X and why 10/100/1000 link speed is mutually exclusive with 2500. But the connected external PHY are twisted pair cable which only supports 2500baseT_full.
The PHY should indicate what modes its supports. The PHY drivers
get_features() call should set supported to only 2500baseT_Full, if
that is all it supports.
What modes are actually used should then be the intersect of what both
the MAC and the PHY indicate they can do.
Andrew