Booting over NFS - PHY autonegotiation issues

[Jakub Klama]

Hi,

We have a problem booting FreeBSD from NFS root after upgrade to newest 
HEAD
on Marvell 88F6281 (using driver mge) and Freescale MPC8572 (using 
driver tsec).
Problem is related to changes in sys/net/route.h (RT_LINK_IS_UP macro) and
PHY autonegotation, similar to:

http://lists.freebsd.org/pipermail/freebsd-ppc/2010-March/004134.html

Here's output from Marvell 88F6281:
#v+
(...)
WARNING: WITNESS option enabled, expect reduced performance.
WARNING: DIAGNOSTIC option enabled, expect reduced performance.
Root mount waiting for: usbus0
uhub0: 1 port with 1 removable, self powered
Trying to mount root from nfs:10.0.0.201:/nfsroot/mv6281-2/
krpc_call: sosend: 65
NFS_ROOT: NFSv3 mount failed (error: 65). Trying NFSv2 ...
krpc_call: sosend: 65
nfs_mountroot: md_mount(): 65
ROOT MOUNT ERROR:
If you have invalid mount options, reboot, and first try the following from
the loader prompt:

     set vfs.root.mountfrom.options=rw

and then remove invalid mount options from /etc/fstab.

Trying to mount root from nfs:
ifaddr cache = 0xc3e18500  is deleted
nfs_mountroot: RTM_ADD: 17
ROOT MOUNT ERROR:
(...)
#v-

We've managed changes that prevents restarting autonegotiation and allows
to boot from NFS correctly, based on investigating other PHY drivers (such
as rlphy) and mii_phy_setmedia():

on Marvell (mge/e1000phy):
#v+
--- a/sys/dev/mii/e1000phy.c
+++ b/sys/dev/mii/e1000phy.c
@@ -349,7 +349,9 @@ e1000phy_service(struct mii_softc *sc, struct 
mii_data *mii, int cmd)
                        break;
 
                if (IFM_SUBTYPE(ife->ifm_media) == IFM_AUTO) {
-                       e1000phy_mii_phy_auto(esc);
+                       if ((PHY_READ(sc, MII_BMCR) & BMCR_AUTOEN) == 0 ||
+                          (sc->mii_flags & MIIF_FORCEANEG))
+                               e1000phy_mii_phy_auto(esc);
                        break;
                }
#v-

and on MPC8572 (tsec/ciphy):
#v+
--- a/sys/dev/mii/ciphy.c
+++ b/sys/dev/mii/ciphy.c
@@ -176,13 +176,12 @@ ciphy_service(struct mii_softc *sc, struct 
mii_data *mii, int cmd)
 
                switch (IFM_SUBTYPE(ife->ifm_media)) {
                case IFM_AUTO:
-#ifdef foo
                        /*
                         * If we're already in auto mode, just return.
                         */
                        if (PHY_READ(sc, CIPHY_MII_BMCR) & 
CIPHY_BMCR_AUTOEN)
-                               return (0);
-#endif
+                               break;
+
                        (void) mii_phy_auto(sc);
                        break;
#v-

Is this preferred way to fix this issue?

Of course, with this fix, manually restarting autonegotiation using
'ifconfig mge0 media auto' doesn't work - but it doesn't work also on
other PHY's (we've tested it on rl/rlphy).

-- 
Jakub Klama.