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Date: Mon, 29 Aug 2011 13:05:06 +0200
From: Jan Kiszka <jan.kiszka@siemens.com>
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Subject: Re: [Qemu-devel] HPET configuration in Seabios
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To: Avi Kivity <avi@redhat.com>
Cc: Andrew Theurer <habanero@linux.vnet.ibm.com>, Gleb Natapov <gleb@redhat.com>, "kvm@vger.kernel.org list" <kvm@vger.kernel.org>, seabios <seabios@seabios.org>, ya su <suya94335@gmail.com>, Alexander Graf <agraf@suse.de>, QEMU Developers <qemu-devel@nongnu.org>, Kevin O'Connor <kevin@koconnor.net>

On 2011-08-29 13:00, Avi Kivity wrote:
> On 08/29/2011 01:25 PM, Jan Kiszka wrote:
>>>
>>>  Can't seabios just poke at the hpet itself and see if it exists or not?
>>>
>>
>> Would be hard for the BIOS to guess the locations of the blocks unless
>> we define the addresses used by QEMU as something like base + hpet_no *
>> block_size in all cases.
>>
> 
> Currently we have a fixed address.  We could do:
> 
>   if available in fw_cfg:
>       use that (may indicate no hpet)
>   elif fixed address works:
>       use that
>   else
>       no hpet

Currently, we also only have a single HPET block, but that's just
because of some QEMU limitations that will vanish sooner or later. Then
nothing will prevent multiple "-device hpet,base=XXX".

Jan

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