Re: [patch 1/6] pasemi_mac: Move RX/TX section enablement to dma_lib

[Olof Johansson <olof@lixom.net>]

Hi,

On Tue, Feb 26, 2008 at 10:46:06PM +1100, Michael Ellerman wrote:
> On Wed, 2008-02-20 at 20:57 -0600, Olof Johansson wrote:
> > +	i = 1000;
> > +	pasemi_write_dma_reg(PAS_DMA_COM_RXCMD, 0);
> > +	while ((i > 0) && (pasemi_read_dma_reg(PAS_DMA_COM_RXSTA) & 1))
> > +		i--;
> > +	if (i < 0)
> > +		printk(KERN_INFO "Warning: Could not disable RX section\n");
> > +
> > +	i = 1000;
> > +	pasemi_write_dma_reg(PAS_DMA_COM_TXCMD, 0);
> > +	while ((i > 0) && (pasemi_read_dma_reg(PAS_DMA_COM_TXSTA) & 1))
> > +		i--;
> 
> This kind of caught my eye, is it still going to work when the next core
> is twice as fast?

Actually, I added the variable right before posting, I used to have an
infinite loop there while testing the patch. I've never seen it do more
than a few rounds, so I'm not that worried.

We already have a similar loop in the channel shutdown code, but it runs
a bit longer. I might bring that over instead. Thanks for pointing it
out.


-Olof