Aw: Re: Re: [PATCH net-next v12 08/18] net: ethernet: mtk_eth_soc: fix 1000Base-X and 2500Base-X modes

[Frank Wunderlich]

Just to make it clear...the issue with the copper-sfps is no regression of this series it exists before.
i only had none of them to test for until this weekend....my 1g fibre-sfp were working fine with the inband-flag.

this patch tries to fix it in mtk driver, this was rejected (as far as i understand it should be handled in phylink core instead of pcs driver).
and no more in the v13, so we try to fix it another way.

whatever i do in phylink_parse_mode the link is always inband...i tried to add a new state to have the configuration not FIXED or PHY or INBAND

drivers/net/phy/phylink.c
@@ -151,6 +151,7 @@ static const char *phylink_an_mode_str(unsigned int mode)
                [MLO_AN_PHY] = "phy",
                [MLO_AN_FIXED] = "fixed",
                [MLO_AN_INBAND] = "inband",
+               [MLO_AN_INBAND_DISABLED] = "inband disabled",
        };

include/linux/phylink.h
@@ -20,6 +20,7 @@ enum {
        MLO_AN_PHY = 0, /* Conventional PHY */
        MLO_AN_FIXED,   /* Fixed-link mode */
        MLO_AN_INBAND,  /* In-band protocol */
+       MLO_AN_INBAND_DISABLED

is my start the right way?

i noticed that sfp-handling is always calling phylink_sfp_config_optical and this calls phylink_sfp_set_config with fixed MLO_AN_INBAND.

https://elixir.bootlin.com/linux/v6.3-rc1/source/drivers/net/phy/phylink.c#L3038

This looks wrong for me...
First not all sfp are optical (ethtool shows FIBRE for copper-sfps too) and not all use inband mode...
after changing this to my new state i see it in the configuration message.

@@ -3044,7 +3049,7 @@ static int phylink_sfp_config_optical(struct phylink *pl)

        pl->link_port = pl->sfp_port;

-       phylink_sfp_set_config(pl, MLO_AN_INBAND, pl->sfp_support, &config);
+       phylink_sfp_set_config(pl, MLO_AN_INBAND_DISABLED, pl->sfp_support, &config);

        return 0;
 }

root@bpi-r3:~# ip link set eth1 up
[   30.186811] mtk_soc_eth 15100000.ethernet eth1: configuring for inband disabled/2500base-x link mode

changing the mode itself is not enough for getting the link up...
have not found spacial handling of MLO_AN_INBAND except in phylink_mac_initial_config where i added my mode to the
MLO_AN_INBAND as fallthrough (there is not autoneg set/done). also disabled link_config.an_enabled whereever i've found,
but this does not bring up the link on the copper sfps...it looks like there must be a state-change...

but here i'm stuck with my limited knowledge ;(

regards Frank