lkml.org 
[lkml]   [2001]   [Mar]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: The IO problem on multiple PCI busses

Benjamin Herrenschmidt writes:
> I'm, of course open to any comments about this (in fact, I'd really like
> some feedback). One thing is that we also need to find a way to pass
> those infos to userland. Currently, we implement an arch-specific syscall
> that allow to retreive the IO physical base of a given PCI bus. That may
> be enough, but we may also want something that match more closely what we
> do in the kernel.

Same problem on sparc64. Using a special PCI syscall is fine, _if_ we
all end up using the same one. However, I would prefer another
mechanism...

I think a cleaner scheme is to allow mmap() on
/proc/bus/pci/${BUS}/${DEVICE} nodes, that is much cleaner and solves
transparently any "different word size between userland and kernel"
issues (specifically 32-bit userlands executing on 64-bit kernels).

I played around with something akin to this, and some of the necessary
Xfree86-4.0.x hackery needed, some time ago. But I never finished
this.

Later,
David S. Miller
davem@redhat.com

-
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/

\
 
 \ /
  Last update: 2005-03-22 13:29    [W:0.099 / U:0.032 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site