Xilinx Temac Timer ?

khollan khollan at daktronics.com
Thu Mar 27 04:03:18 EST 2008


What is the purpose of stopping the timer in the ioctl call to read a PHY
register?  This is the code:

    case SIOCGMIIREG:   /* Read GMII PHY register. */
    case SIOCDEVPRIVATE + 1:    /* for binary compat, remove in 2.5 */
        if (data->phy_id > 31 || data->reg_num > 31)
            return -ENXIO;

        /* Stop the PHY timer to prevent reentrancy. */
        spin_lock_irqsave(&XTE_spinlock, flags);

        ret = XTemac_PhyRead(&lp->Emac, data->phy_id,
                       data->reg_num, &data->val_out);

        /* Start the PHY timer up again. */
        lp->phy_timer.expires = jiffies + 2 * HZ;
        spin_unlock_irqrestore(&XTE_spinlock, flags);
        if (ret != XST_SUCCESS) {
                   "%s: XTemac: could not read from PHY, error=%d.\n",
                   dev->name, ret);
            return -EBUSY;
        return 0;

I ask because I have an application that needs to read a Phy register before
the timer has started to see if a link is present.  This causes a kernel bug
when trying to run the del_timer_sync function because there is not a
running timer.  I would like to know if it is safe to remove the timer del
and add but keep the spin lock.

Thanks for your help

View this message in context: http://www.nabble.com/Xilinx-Temac-Timer---tp16306218p16306218.html
Sent from the linuxppc-embedded mailing list archive at Nabble.com.

More information about the Linuxppc-embedded mailing list