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* RE: Fwd: hpet patches
@ 2005-06-14 22:37 Pallipadi, Venkatesh
  2005-06-14 23:11 ` Jon Smirl
  0 siblings, 1 reply; 12+ messages in thread
From: Pallipadi, Venkatesh @ 2005-06-14 22:37 UTC (permalink / raw)
  To: Jon Smirl, Bob Picco; +Cc: Andrew Morton, lkml

 

>-----Original Message-----
>From: Jon Smirl [mailto:jonsmirl@gmail.com] 
>Sent: Tuesday, June 14, 2005 2:51 PM
>To: Bob Picco
>Cc: Pallipadi, Venkatesh; Andrew Morton; lkml
>Subject: Re: Fwd: hpet patches
>
>On 6/14/05, Bob Picco <bob.picco@hp.com> wrote:
>> Jon Smirl wrote:        [Tue Jun 14 2005, 01:50:49PM EDT]
>> > Problem like this are usually fixed with quirks:
>> >
>> > DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,
>> > PCI_DEVICE_ID_INTEL_82801EB_0,  quirk_intel_ich5_hpet);
>> >
>> > quirk_intel_ich5_hpet()
>> > {
>> >     if (!hpet_address)
>> >           hpet_address = 0xfed00000ULL;
>> > }
>> >
>> > 0xfed00000ULL is right for ICH5, do you want to start 
>adding these as
>> > part of HPET support? My hpet works fine once the address 
>is set. For
>> > complete coverage you need a list of these for all of the AMD/Intel
>> > chipsets with hpet support. The list isn't very big.
>> >
>> Well my ignorance is going to show here.  The platform 
>initialization code
>> has already run and PCI probing happens later.  How do you 
>reconcile Venki's
>> concern for an HPET armed for legacy support when platform
>> is already using PIT?  Also the hpet driver isn't a PCI driver but
>> ACPI driver.  It's working for you so I'm obviously missing a detail.
>
>You don't actually use the PCI_FIXUP macros. You make a new one called
>ACPI_FIXUP and run them right after ACPI is read and before you do
>anything else. I was just illustrating how the quirk fixup system
>worked.
>
>To make it work on my system I just added an assignment statement for
>the fix right after the ACPI code looked for the HPET entry. But
>that's not a general solution, building the ACPI_FIXUP macros is one.
>

OK. I was thinking PCI fixup is to late in the initialization for 
HPET fixup. But, we should be OK with a new ACPI_FIXUP macro. My only
other concern is, we should safely fallback to PIT, when our fixed_up 
HPET address isn't right.

Thanks,
Venki


^ permalink raw reply	[flat|nested] 12+ messages in thread
* RE: Fwd: hpet patches
@ 2005-06-14 23:16 Pallipadi, Venkatesh
  2005-06-14 23:36 ` Jon Smirl
  0 siblings, 1 reply; 12+ messages in thread
From: Pallipadi, Venkatesh @ 2005-06-14 23:16 UTC (permalink / raw)
  To: Jon Smirl; +Cc: Bob Picco, Andrew Morton, lkml


>-----Original Message-----
>From: Jon Smirl [mailto:jonsmirl@gmail.com] 
>Sent: Tuesday, June 14, 2005 4:11 PM
>To: Pallipadi, Venkatesh
>Cc: Bob Picco; Andrew Morton; lkml
>Subject: Re: Fwd: hpet patches
>
>On 6/14/05, Pallipadi, Venkatesh <venkatesh.pallipadi@intel.com> wrote:
>> OK. I was thinking PCI fixup is to late in the initialization for
>> HPET fixup. But, we should be OK with a new ACPI_FIXUP macro. My only
>> other concern is, we should safely fallback to PIT, when our fixed_up
>> HPET address isn't right.
>
>If we're keying off from the PCI ID for the chip, how can it not have
>the device? On the other hand, it would probably be good to always do
>a little test on the HPET and fall back to the PIT if the HPET is
>dead.

HPET device itself can be there. But, it can appear in different 
addresses. Most commonly used address is 0xfed00000. But, it can be 
different as well. 

Thanks,
Venki

^ permalink raw reply	[flat|nested] 12+ messages in thread
* RE: Fwd: hpet patches
@ 2005-06-15 17:15 Pallipadi, Venkatesh
  2005-06-15 17:54 ` Jon Smirl
  0 siblings, 1 reply; 12+ messages in thread
From: Pallipadi, Venkatesh @ 2005-06-15 17:15 UTC (permalink / raw)
  To: Jon Smirl; +Cc: Bob Picco, Andrew Morton, lkml

 

>-----Original Message-----
>From: Jon Smirl [mailto:jonsmirl@gmail.com] 
>Sent: Tuesday, June 14, 2005 4:37 PM
>To: Pallipadi, Venkatesh
>Cc: Bob Picco; Andrew Morton; lkml
>Subject: Re: Fwd: hpet patches
>
>On 6/14/05, Pallipadi, Venkatesh <venkatesh.pallipadi@intel.com> wrote:
>> HPET device itself can be there. But, it can appear in different
>> addresses. Most commonly used address is 0xfed00000. But, it can be
>> different as well.
>
>Does Intel build different versions of something like an 82801EB with
>the HPET at different addresses and still have the same part number?
>For a specific part number/PCI ID isn't HPET always in the same place?
>If the HPET is going to be in a different place I would expected the
>chip would have a different PCI ID.
>

The specification for ICH5 has the details about this address
http://www.intel.com/design/chipsets/datashts/25251601.pdf (Chapter 17).
We need to look at specific device address to figure out the HPET base 
address in this case.


Thanks,
Venki

^ permalink raw reply	[flat|nested] 12+ messages in thread

end of thread, other threads:[~2005-06-16 14:01 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
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2005-06-14 17:50     ` Fwd: hpet patches Jon Smirl
2005-06-14 18:38       ` Bob Picco
2005-06-14 21:51         ` Jon Smirl
2005-06-14 22:37 Pallipadi, Venkatesh
2005-06-14 23:11 ` Jon Smirl
2005-06-14 23:16 Pallipadi, Venkatesh
2005-06-14 23:36 ` Jon Smirl
2005-06-15  0:51   ` Andi Kleen
2005-06-15 17:15 Pallipadi, Venkatesh
2005-06-15 17:54 ` Jon Smirl
2005-06-15 18:11   ` Lee Revell
2005-06-16 14:00   ` Vitezslav Samel

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