Re: Re: [PATCH] PNPACPI: handle address descriptors in _PRS

[Shaohua Li <shaohua.li-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>]

On Wed, 2005-09-21 at 23:27 +0800, Bjorn Helgaas wrote:
> On Tuesday 20 September 2005 7:17 pm, Shaohua Li wrote: 
> > On Tue, 2005-09-20 at 16:26 -0600, Bjorn Helgaas wrote: 
> > > PNPACPI complained about and ignored devices with ADDRESS16,
> ADDRESS32, 
> > > or ADDRESS64 descriptors in _PRS.  Those descriptors seem
> legitimate, 
> > > and HP firmware uses them for built-in serial ports, so this patch
> adds 
> > > support for them.
> 
> > You might have missed the similar change in pnpacpi_encode_resources
> in 
> > your patch. It's used when we assign new resources (_SRS method) to
> pnp 
> > devices.
> 
> You're right, I did miss the corresponding encoding change.  I'll 
> add that.  I feel a bit uneasy about it, though, because it will be 
> a fair amount of code, and I don't know how to test it.  Do we ever 
> really use _SRS today?  And there's information lost when decoding 
> the ACPI resources, such as the _TRA.
We did use _SRS, at least under x86. This only is done when some PNP
devices havn't resources, so only very small number of systems need it.
Ignoring it might be ok currently, if HP firmware always assigns
resources to PNP devices. Yes, we did lose the info of _TRA. I didn't
find any system uses it. Maybe some big IA64 systems use.

Thanks,
Shaohua



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