Atheros 9285 & Atheros AR8131

[John Baldwin]

On Monday, March 28, 2011 2:06:27 pm John Baldwin wrote:
> On Monday, March 28, 2011 12:46:02 pm Ксензов Алексей wrote:
> > 2011/3/29 Sergio de Almeida Lenzi <lenzi.sergio at gmail.com>
> > 
> > >
> > >  This is probably due to a problem FreeBSD has with ACPI initialization
> > > sometimes wiping out the state in PCI-PCI bridges for resource windows and not
> > > gracefully recovering from that.  I have some early work in progress to
> > > address this, but it will be a while before I have something ready for
> > > testing.
> > >
> > >
> > >  it is the acer bios that is does not follow acpi standard... I have the
> > > same problem
> > > in an old acer 5050 no solution still...   I had to install linux in that
> > > notebook.
> > >
> > > My advice is not to buy acer... they are cheap any good...
> > >
> > > Well let's wait for the Baldwin fix....
> > >
> > >
> > maybe this can be corrected by editing the ASL?
> 
> We've never figured out what is zeroing the registers in the PCI-PCI bridges.
> I suspect it is not something in the ASL, but is a side effect of some BIOS
> code that runs in SMM when ACPI is turned on.

Ok, so I have a patch to rework how PCI-PCI bridges manage resources for
devices.  This patch applies to HEAD, no idea if it applies to older branches
(likely not).  You will need to add the option 'NEW_PCIB' to your kernel
config after applying this patch.

  http://www.FreeBSD.org/~jhb/patches/pcib_new.patch

For my local testing I used a hack to wipe out the PCI-PCI bridges in my
test machine similar to what the BIOS does on these machines.  The bridges
all grew windows to match their original BIOS-assigned windows based on the
BIOS-assigned resources in the BARs of the child devices.

These patches should also let us allocate new resources from scratch for
devices behind PCI-PCI bridges once we have better support for determining what
are valid PCI address ranges in the Host-PCI bridge drivers.

-- 
John Baldwin