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Date: Fri, 26 Jul 2013 11:06:34 +0200
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v3 14/14] i386: ACPI table generation code
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>, qemu-devel@nongnu.org

  Hi,

>> You can look at the tables without doing a full linker pass first, so
>> the firmware can easily initialize the hardware according to what it
>> finds in specific acpi tables.  Check FADT for pm_base.  Check MCFG for
>> mmconf xbar location.
>>
>> cheers,
>>   Gerd
> 
> That's something I think that it's best for firmware to avoid.
> Much better to load tables in memory and use standard ACPI
> methods to find specific tables.

Problem is this happens relatively late in the firmware boot process.

> It's a general thing: paravirtualization is often easier
> but let's use standard interfaces where possible.

Sure.  Thats why I want read the info from the acpi tables.  Being able
to do that without a full acpi table linker pass makes this easier for
the firmware, especially for informations needed very early in the
initialization process.

What is wrong with etc/acpi/fadt ?

> Sticking everything in one file will serve to keep firmware
> honest and not let it cut corners.

Parse error.

cheers,
  Gerd