Re: [patch 2.6.13 2/2] 3c59x: add option for using memory-mapped PCI I/O resources

[Andrew Morton <akpm@osdl.org>]

"John W. Linville" <linville@tuxdriver.com> wrote:
>
> On Tue, Sep 06, 2005 at 03:15:46PM -0700, Andrew Morton wrote:
> > "John W. Linville" <linville@tuxdriver.com> wrote:
> > >
> > > I fully intend to have have a flag in the private data set based on
> > >  the PCI ID when I accumulate some data on which devices support this
> > >  and which don't.  So far I've only got a short list...  Do you think
> > >  such a flag should be based on which ones work, or which ones break?
> > 
> > The ones which are known to work.
> > 
> > Bear in mind that this is an old, messy and relatively stable driver which
> > handles a huge number of different NICs.   Caution is the rule here.
> 
> I definitely agree.  That is another part of why I defaulted to "use_mmio=0".
> 
> I'll post PCI ID based patches as I determine supported cards.
> 

What I'd suggest you do is to look at enabling the feature for, say,
IS_CYCLONE and IS_TORNADO NICs.  Do that as a separate -mm patch, make sure
that an explicit `use_mmio=0' will still turn it off.

So in the style of that driver, something like:

static int use_mmio[MAX_UNITS] = { [ 0 .. MAX_UNITS-1 ] = -1, };

Then:

	if (module parm given)
		use_mmio[unit] = 1 or 0

	...

	/* Determine the default if the user didn't override us */
	if (use_mmio[unit] == -1 && (IS_CYCLONE || IS_TORNADO))
		use_mmio[unit] = 1;

	priv->use_mmio = use_mmio[unit];	(maybe)

	....

	if (priv->use_mmio == 1)
		do mmio stuff


There's a bit to be done here, so I'll drop your initial set of patches.

btw, Donald Becker's 3c59x.c has done mmio for ages.  Suggest you take a
look in there. http://www.scyld.com/vortex.html
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/