From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: TG3 data corruption (TSO ?)
Date: Mon, 11 Sep 2006 15:25:48 +1000
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Cc: Segher Boessenkool <segher@kernel.crashing.org>,
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To: Michael Chan <mchan@broadcom.com>
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On Sun, 2006-09-10 at 22:18 -0700, Michael Chan wrote:
> Benjamin Herrenschmidt wrote:
> 
> > I've added a wmb() in tw32_rx_mbox() and tw32_tx_mbox() and can still
> > reproduce the problem. I've also done a 2 days run without TSO enabled
> > without a failure (my test program normally fails after a couple of
> > minutes).
> > 
> 
> Hi Ben,
> 
> The code is a bit tricky.  It uses function pointers for the various
> register read/write methods.  For the 5780, I believe it will be
> assigned a simple writel() and not tg3_write32_tx_mbox().  Can you
> double check to make sure you have actually added the wmb()?
> 
> It's probably easiest to just add the wmb() in tg3_xmit_dma_bug()
> before the tw32_tx_mbox().

I've done:

#define tw32_rx_mbox(reg, val)	do { wmb(); tp->write32_rx_mbox(tp, reg, val); } while(0)
#define tw32_tx_mbox(reg, val)	do { wmb(); tp->write32_tx_mbox(tp, reg, val); } while(0)

Cheers,
Ben.