Olimex SAM9-L9260 autonegotiation fail

Development Boards MicroMod
1

Hi,

The ethernet port of my SAM9-L9260 doesn’t work correctly when the board is connected to 100Mb network device (switch, router, PC with cross cable, …). When I force port with mii-tool to 10BaseTx-FD or 10BaseTx-HD everything is OK. When the board is connected to 10Mb switch the port works correctly. The behaviour of U-BOOT and pre-installed from Olimex kernel and rootfs is absolutely the same. Is it common problem of this board, and how the problem could be solved?

Thank you very much.

2

The ethernet port of my SAM9-L9260 doesn’t work correctly when the board is connected to 100Mb network device (switch, router, PC with cross cable, …). When I force port with mii-tool to 10BaseTx-FD or 10BaseTx-HD everything is OK.

I'm debugging a certain EMAC+PHY with much struggles. The following piece of code might help to see what PHY register returns after AN process. 
void     
mii_dealan(struct local *l, unsigned timo) 
{
        unsigned anar, bound;

        anar = ANAR_TX_FD | ANAR_TX | ANAR_10_FD | ANAR_10 | ANAR_CSMA;
        mii_write(l, l->phy, MII_ANAR, anar);
        mii_write(l, l->phy, MII_BMCR, BMCR_AUTOEN | BMCR_STARTNEG);
        l->anlpar = 0;  
        bound = getsecs() + timo;
        do {
                l->bmsr = mii_read(l, l->phy, MII_BMSR) |
                   mii_read(l, l->phy, MII_BMSR); /* read twice */
                if ((l->bmsr & BMSR_LINK) && (l->bmsr & BMSR_ACOMP)) {
                        l->anlpar = mii_read(l, l->phy, MII_ANLPAR);
                        break;
                }
                DELAY(10 * 1000);
        } while (getsecs() < bound);
        return;
}

When succesful return, l->anlpar contains link partner abilities to talk. Note that AN process takes 1~3 seconds to complete and it’s very long time considering how quick other parts of the entire system work. That means for interrupt driven software design it’d be prohibitive to busy-wait with interrupt disabled.

a bit concern about 9260 MII. According to PDF, a set of register must be prepared to make the MII connection work correctly. This involves correct electronics design “open-drain, pull-up, pull-down” matters. Check schematics and register setting. It’d, however, make little sense about “100 fails, 10 OK” symptoms admittingly.