Re: [Broken] PCI: clean up resource alignment management

[Jesse Barnes <jbarnes@virtuousgeek.org>]

On Tuesday, April 22, 2008 3:13 pm Linus Torvalds wrote:
> On Tue, 22 Apr 2008, Linus Torvalds wrote:
> > (In fact, I think cardbus bridges have a much more flexible alignment
> > than that size thing, and can be aligned at finer granularity, but I
> > forget the exact details, and since we didn't add a special "alignment"
> > field, we can't take advantage of it anyway).
>
> Yeah, I double-checked: the IO alignment is 4 bytes, the MEM alignment is
> 4k.
>
> So if we had a separate alignment word we could use that, but in the
> meantime I think IORESOURCE_SIZEALIGN is good enough, and a bit more
> readable than the STARTALIGN thing.
>
> Now we just need to have somebody test it. It turns out that I no longer
> have any Cardbus cards, since my laptops now all have built-in wireless.
> Boo hiss for me.

I may be in the same boat, I'll have to dig around and see if I have any...  
That said, I think an explicit alignment field would make things even cleaner 
(and like you said allow us to take advantage of bus specific alignment 
better).

Jesse