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Subject: Re: Sun GEM PPC32 Bug?
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "R. Herbst" <ruediger.herbst@googlemail.com>
Cc: linux-kernel@vger.kernel.org, David Miller <davem@davemloft.net>,
        Matt <jackdachef@gmail.com>, geert@linux-m68k.org
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Date: Sun, 06 Feb 2011 10:45:49 +1100
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> If I find some time tonight, else tomorrow, I'll whip up a couple of
> patches:
> 
>  - One simpler re-arranging our Rx reset sequence and adding a test for
> the overflow bit at the end, printing out the results, etc... 
> 
>  - One that basically always reset the chip on overflow.

Actually, the second one is trivial, just modify gem_rxmac_interrupt()
as follow:

	if (rxmac_stat & MAC_RXSTAT_OFLW) {
		u32 smac = readl(gp->regs + MAC_SMACHINE);

		netdev_err(dev, "RX MAC fifo overflow smac[%08x]\n", smac);
		gp->net_stats.rx_over_errors++;
		gp->net_stats.rx_fifo_errors++;

-		ret = gem_rxmac_reset(gp);
+		ret = 1;
	}

And tell us if that makes a difference.

Cheers,
Ben.