lkml.org 
[lkml]   [2008]   [Sep]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [Bug #11550] pnp: Huge number of "io resource overlap" messages

* Bjorn Helgaas <bjorn.helgaas@hp.com> wrote:

> The problem seems to be that Frans has some PCI devices that are not
> configured by the BIOS, and their BARs contain zero. A PNP quirk
> checks for overlaps of PCI devices and PNP devices, and those zero-
> valued BARs of course conflict with the PNP motherboard devices that
> describe legacy hardware.
>
> Here's another approach based on section 3.5 of the PCI Firmware spec.
> It says:
>
> Since not all devices may be configured prior to the operating
> system handoff, the operating system needs to know whether a
> specific BAR register has been configured by firmware. The operating
> system makes the determination by checking the I/O Enable, and
> Memory Enable bits in the device's command register, and Expansion
> ROM BAR enable bits. If the enable bit is set, then the corresponding
> resource register has been configured.
>
> So instead of checking whether the BAR contains zero, the patch below
> checks the I/O, Mem, and ROM BAR enable bits to determine whether a
> BAR is enabled.

cool! Looks like a pretty significant fix, for all sorts of legacy
devices. Worth backporting?

Ingo


\
 
 \ /
  Last update: 2008-09-27 22:57    [W:0.143 / U:6.140 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site