RTL8125, Is there a way to enable this option?

[rtlques]

gigabit lite option is also disabled by default in Windows.
Is there any way to enable this option in pfsense?

[stephenw10]

Not that I've ever seen. Also I have no idea why you would ever want to. It seems to be some 500Mb mode. I would assume both ends have to support it. Seems like something non-standard.

What are you trying to use it for?

Steve

[stephenw10]

Mmm, interesting:

Giga Lite (500M) mode allows two link partners that both support 1000Base-T and Giga Lite mode to transmit at 500Mbps data rate if only two pairs (AB pairs) can be detected in the CAT.5 UTP cable. This feature is a Realtek proprietary feature and it conforms to the 802.3az-2010(EEE) specification.

But, no I've never seen anything use it or any mention of it in a driver.

Steve

[JKnott]

@stephenw10 said in RTL8125, Is there a way to enable this option?:

Also I have no idea why you would ever want to.

Fewer calories?

Actually, I really don't see the need for this either? If only 2 pairs are usable, then you have a defective cable, which should be replaced. I suppose it's someone's solution for a problem that doesn't exist.

[stephenw10]

Mmm, now I see what it does I guess I can see how it would be useful if you do have only 2 pairs for whatever reason. 5x better than 100M
But it should only ever be a fallback option and both ends need to support it. I wouldn't expect it to make any difference except in that very specific circumstance.

Steve

[rtlques]

@stephenw10
One direction of upper line is already set, just need to set up pfsense
(installed latest version 1.9.7 RTL driver with pfsense ce 2.6)
"if_re.c" file contains keywords for "giga lite" in RTL official freebsd driver "rtl_bsd_drv_v197.00.tgz"
i don't know how to do it, but hope there is a way to enable

[stephenw10]

So you are trying to use a 4 wire link? And currently only seeing 100M?

[stephenw10]

It looks like it's mentioned in two places. One where it's disabled for a list of MAC types:

        if (sc->re_type == MACFG_68 || sc->re_type == MACFG_69 ||
            sc->re_type == MACFG_70 || sc->re_type == MACFG_71 ||
            sc->re_type == MACFG_72 || sc->re_type == MACFG_73 ||
            sc->re_type == MACFG_74) {
                //Disable Giga Lite
                MP_WritePhyUshort(sc, 0x1F, 0x0A42);
                ClearEthPhyBit(sc, 0x14, BIT_9);

And the other where it's disabled unconditionally in the setup function for the 8125:

static int re_ifmedia_upd_8125(struct ifnet *ifp)
{
        struct re_softc	*sc = ifp->if_softc;
        struct ifmedia	*ifm = &sc->media;
        int anar;
        int gbcr;
        int cr2500 = 0;

        if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
                return(EINVAL);

        //Disable Giga Lite
        ClearEthPhyOcpBit(sc, 0xA428, BIT_9);
        ClearEthPhyOcpBit(sc, 0xA5EA, BIT_0);

        cr2500 = MP_RealReadPhyOcpRegWord(sc, 0xA5D4);
        cr2500 &= ~RTK_ADVERTISE_2500FULL;

Neither has any sort of external config dependency so it doesn't look like you can choose.
And it looks like it's always disabled in the 8125.

Steve