On Wed, Feb 26, 2020 at 08:22:39PM +0200, Vladimir Oltean wrote:

On Wed, 26 Feb 2020 at 20:21, Vladimir Oltean [off-list ref] wrote:

quoted

On Wed, 26 Feb 2020 at 15:36, Russell King - ARM Linux admin
[off-list ref] wrote:

quoted

dpaa2 is complicated by the firmware, and that we can't switch the
interface mode between (SGMII,1000base-X) and 10G.

If the firmware is in "DPMAC_LINK_TYPE_PHY" mode, it expects to be told
the current link parameters via the dpmac_set_link_state() call - it
isn't clear whether that needs to be called for other modes with the
up/down state (firmware API documentation is poor.)

With PCS control in Linux, I am pretty sure that you don't want
anything other than DPMAC_LINK_TYPE_PHY anyway.
Basically in DPMAC_LINK_TYPE_FIXED, the MC firmware is in control of
the PCS and polls its link state to emit link notifications to objects
connected to the DPMAC. So Linux control of PCS would class with

s/class/clash/

quoted

firmware control of the PCS, leading to undesirable side-effects to
say the least.

Yes, which is why we only register the PCS with phylink if we're in
DPMAC_LINK_TYPE_PHY mode.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up