On Sunday, 23 of December 2007, Carlos Corbacho wrote:
> Fix suspend-to-RAM on nForce 4 (CK804) boards by increasing
> PCIBIOS_MIN_IO.
>
> Fixes kernel bugzilla #9528
>
> Problem:
>
> Linus' patch (52ade9b3b97fd3bea42842a056fe0786c28d0555) to re-order
> suspend (and fix fall out from Rafael's earlier suspend reordering work)
> broke suspend-to-RAM on nForce 4 (CK804) boards.
>
> Why:
>
> After debugging _PTS() in the DSDT, it turns out these nVidia boards are
> trying to write to an IO port > 0x1000 (0x142E) during suspend. Before the
> re-ordering, we got away with this.
>
> After the afore mentioned commit, we started hitting the PCIBIOS_MIN_IO
> limit and suspend then broke on these machines (the machine simply hangs
> when it reaches the 0x142E IO port write during suspend-to-RAM).
>
> There was some previous work in the PCIBIOS_MIN_IO area over two years ago
> (71db63acff69618b3d9d3114bd061938150e146b) which bumped this to 0x4000,
> but this was reverted (2ba84684e8cf6f980e4e95a2300f53a505eb794e) after
> causing new and entirely different problems on another nForce board.
>
> 0x1500 has been picked here as a nice, round and more conservative value
> than 0x4000, and which covers 0x142E.
The patch is fine by me, so if anyone has objections, please speak up.
Thanks,
Rafael
> Tested on x86-64.
>
> Signed-off-by: Carlos Corbacho <[email protected]>
> CC: Rafael J. Wysocki <[email protected]>
> CC: Linus Torvalds <[email protected]>
> CC: Greg KH <[email protected]>
> CC: Ingo Molnar <[email protected]>
> CC: Thomas Gleixner <[email protected]>
> CC: Len Brown <[email protected]>
> ---
> Since it's not entirely clear who is responsible for what in this file,
> and given what it fixes, I'm CC'ing you all in the hope that someone
> will handle this.
>
> include/asm-x86/pci.h | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
>
> diff --git a/include/asm-x86/pci.h b/include/asm-x86/pci.h
> index e883619..03cb123 100644
> --- a/include/asm-x86/pci.h
> +++ b/include/asm-x86/pci.h
> @@ -46,7 +46,7 @@ extern unsigned int pcibios_assign_all_busses(void);
> #define pcibios_scan_all_fns(a, b) 0
>
> extern unsigned long pci_mem_start;
> -#define PCIBIOS_MIN_IO 0x1000
> +#define PCIBIOS_MIN_IO 0x1500
> #define PCIBIOS_MIN_MEM (pci_mem_start)
>
> #define PCIBIOS_MIN_CARDBUS_IO 0x4000
* Rafael J. Wysocki <[email protected]> wrote:
> > 0x1500 has been picked here as a nice, round and more conservative
> > value than 0x4000, and which covers 0x142E.
>
> The patch is fine by me, so if anyone has objections, please speak up.
i'm quite nervous about that approach, partly due to the "black magic"
interaction of commit 2ba84684e8c. Could we try to figure out what's
really going on here, instead of playing with a general limit (which
might break other boxes)?
Ingo
On Sun, 23 Dec 2007, Rafael J. Wysocki wrote:
>
> The patch is fine by me, so if anyone has objections, please speak up.
There is absolutely *no* way I will apply this in an -rc6 release.
The number of machines this will break is totally unknown. It might be
zero. It might be hundreds. We just don't know. We might hit another
unlucky allocation that we just happened to avoid before.
Linus
On Sunday, 23 of December 2007, Linus Torvalds wrote:
>
> On Sun, 23 Dec 2007, Rafael J. Wysocki wrote:
> >
> > The patch is fine by me, so if anyone has objections, please speak up.
>
> There is absolutely *no* way I will apply this in an -rc6 release.
>
> The number of machines this will break is totally unknown. It might be
> zero. It might be hundreds. We just don't know. We might hit another
> unlucky allocation that we just happened to avoid before.
I was rather thinking of putting it into -mm for some time and target for
2.6.25 if possible.
If it breaks systems, we can always revert before 2.6.25 final.
Thanks,
Rafael
Rafael J. Wysocki wrote:
> On Sunday, 23 of December 2007, Linus Torvalds wrote:
>> On Sun, 23 Dec 2007, Rafael J. Wysocki wrote:
>>> The patch is fine by me, so if anyone has objections, please speak up.
>> There is absolutely *no* way I will apply this in an -rc6 release.
>>
>> The number of machines this will break is totally unknown. It might be
>> zero. It might be hundreds. We just don't know. We might hit another
>> unlucky allocation that we just happened to avoid before.
>
> I was rather thinking of putting it into -mm for some time and target for
> 2.6.25 if possible.
>
> If it breaks systems, we can always revert before 2.6.25 final.
>
This is totally the wrong way to go about it.
Instead, it should detect this particular chipset and reserve relevant
ports. Even better would be if we can find out what reserves these
ports and mark it as a quirk.
That being said, I have seen other chipsets allocate ports in the low
0x1XXX range using non-BAR methods. They *should* reserve them in ACPI,
of course.
-hpa
On Sunday 23 December 2007 23:12:47 H. Peter Anvin wrote:
> Rafael J. Wysocki wrote:
> > On Sunday, 23 of December 2007, Linus Torvalds wrote:
> >> On Sun, 23 Dec 2007, Rafael J. Wysocki wrote:
> >>> The patch is fine by me, so if anyone has objections, please speak up.
> >>
> >> There is absolutely *no* way I will apply this in an -rc6 release.
> >>
> This is totally the wrong way to go about it.
Please disregard the patch anyway - my test system was still using the custom
DSDT - it doesn't fix anything.
Regardless, Linus' patch in question (in combination with Rafael's suspend
reordering work) still broke suspend, and the port 0x142E write is still the
offender, so something is still not playing nice - I'm just now at a complete
loss as to what.
(PNPACPI came to mind as a suspect, but even with that disabled, this board/
chipset still wedges on suspend).
-Carlos
--
E-Mail: [email protected]
Web: strangeworlds.co.uk
GPG Key ID: 0x23EE722D
On Mon, 24 Dec 2007, Carlos Corbacho wrote:
>
> Please disregard the patch anyway - my test system was still using the custom
> DSDT - it doesn't fix anything.
Ok, so it's not a simple IO port conflict.
And the range 0x1400-0x147f (which is apparently the ACPI block) is
properly marked as reserved.
So the IO write to 1428 is a red herring. It's just part of the normal
sequence to suspend-to-ram, and while it failing probably has something to
do with the failure to s2ram, it's simply a result of ACPI doing something
insane, and probably making some assumptions that we've broken by mistake
when we do the higher-level device_suspend() before we do the low-level
one.
IOW, it looks like the normal kind of ACPI mess. Color me not in the least
surprised, and it needs somebody who understands AML and what the heck is
supposed to happen to figure out.
The kernel doesn't do anything at all to port 1428 (since it is reserved),
so if any write to it "fails" (how?) it's probably because the writer made
some assumptions about system state.
Linus
On Sun, 23 Dec 2007, Linus Torvalds wrote:
>
> IOW, it looks like the normal kind of ACPI mess. Color me not in the least
> surprised, and it needs somebody who understands AML and what the heck is
> supposed to happen to figure out.
Side note: we could obviously undo the commit that triggered this for you
(ie 52ade9b3b97fd3bea42842a056fe0786c28d0555), but then we have to undo
also the commit that caused us to do that commit in the first place, and
change the ordering on resume too (that would be commit
e3c7db621bed4afb8e231cb005057f2feb5db557 - the commit that moved the
"pm_ops->finish()" call to before the call to device_resume())
In other words, we'd have to go back to our original ordering, which Len
said was fundamentally wrong. I don't think anybody really wants that.
It would be better to figure out why "device_suspend()" apparently causes
problems for your AML crud.
Oh, and why is linux-kernel cc'd, but not linux-pm? Are all the relevant
people from linux-pm cc'd, or should somebody who is on that list please
try to condense this down?
(For linux-pm: see
http://bugzilla.kernel.org/show_bug.cgi?id=9528
for some more details, including a few red herrings like the whole subject
line of this email thread which turned out to not be valid after all).
Linus
On Monday 24 December 2007 01:14:34 Linus Torvalds wrote:
> Side note: we could obviously undo the commit that triggered this for you
> [..]
> In other words, we'd have to go back to our original ordering, which Len
> said was fundamentally wrong. I don't think anybody really wants that.
Nor would I argue to do so.
> It would be better to figure out why "device_suspend()" apparently causes
> problems for your AML crud.
Will do - thanks for the pointer.
> Oh, and why is linux-kernel cc'd, but not linux-pm?
Because I like to compound my errors (I mean, if you're going to screw up, you
might as well _really_ go for it).
-Carlos
--
E-Mail: [email protected]
Web: strangeworlds.co.uk
GPG Key ID: 0x23EE722D
On Monday, 24 of December 2007, Carlos Corbacho wrote:
> On Monday 24 December 2007 01:14:34 Linus Torvalds wrote:
> > Side note: we could obviously undo the commit that triggered this for you
> > [..]
> > In other words, we'd have to go back to our original ordering, which Len
> > said was fundamentally wrong. I don't think anybody really wants that.
>
> Nor would I argue to do so.
>
> > It would be better to figure out why "device_suspend()" apparently causes
> > problems for your AML crud.
>
> Will do - thanks for the pointer.
Well, having considered that for a longer while, I think the AML code is
referring to a device that we have suspended already, and since it's in a low
power state, it just can't handle the reference.
If that is the case, we'll have to find the device (that should be possible
using some code instrumentation) and move the suspending of it into the late
stage.
> > Oh, and why is linux-kernel cc'd, but not linux-pm?
>
> Because I like to compound my errors (I mean, if you're going to screw up, you
> might as well _really_ go for it).
BTW, linux-pm is on linux-foundation, changed the CC. ;-)
Thanks,
Rafael
On Mon, 24 Dec 2007, Rafael J. Wysocki wrote:
>
> Well, having considered that for a longer while, I think the AML code is
> referring to a device that we have suspended already, and since it's in a low
> power state, it just can't handle the reference.
>
> If that is the case, we'll have to find the device (that should be possible
> using some code instrumentation) and move the suspending of it into the late
> stage.
Yes.
In general, I'm personally of the opinion that drivers should *not*
actually go into D3 at all in the regular "->suspend()" phase. It should
be done in ->suspend_late. The early suspend is for saving state and
returning errors.
Sadly, we've made it a bit too inconvenient to actually do that. Almost
all drivers only do the "->suspend" thing, and the default PCI behaviour
doesn't help us in any way either.
Anyway, I wonder if a patch like this could make it easier for driver
writers to handle things. It basically does:
- if you don't have a regular "suspend()" function, we'll just save state
at suspend time.
- if you don't have a "suspend_late()" function, we'll look at the
current state, and if it's still in PCI_D0, we'll suspend to PCI_D3hot
if it's a regular PCI device (ie not a bridge or something else odd).
- then, at resume time, by default we don't do anything in the early
resume, but in the late resume we'll undo everything, of course.
Anyway, with this, most drivers could just remove the
"pci_set_power_state()" call *entirely*, and let the default
suspend_late action power the device down. But if you want to override
that default action, you can either:
- set the power state in your own ->suspend() routine (either by using
pci_set_power_state(), or by just explicitly setting the state to
unknown with "dev->current_state = PCI_UNKNOWN"
- have a "late_suspend()" action, which obviously will override the
default action entirely.
Hmm?
In the case of the NVidia issue, one thing to try migh be to remove the
current call to "pci_set_power_state(pdev, 3);" in agp_nvidia_suspend() in
drivers/char/agp/nvidia-agp.c. That sounds like the most likely culprit
for something that ACPI might want to shut down.
NOTE! This following patch is just for discussion, and while I think it's
conceptually a good thing to try, I don't think it will help Carlos'
problem. But removing the "pci_set_power_state()" in agp_nvidia_suspend()
might.
Linus
---
drivers/pci/pci-driver.c | 32 +++++++++++++++++++++++++-------
1 files changed, 25 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 6d1a216..6992f73 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -264,6 +264,28 @@ static int pci_device_remove(struct device * dev)
return 0;
}
+static void pci_default_suspend(struct pci_dev *dev, pm_message_t state)
+{
+ pci_save_state(dev);
+}
+
+static void pci_default_suspend_late(struct pci_dev *dev, pm_message_t state)
+{
+ /* Something has already suspended it? Never mind then.. */
+ if (dev->current_state != PCI_D0)
+ return;
+
+ /* We avoid powering down bridges by default.. */
+ if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL)
+ pci_set_power_state(dev, PCI_D3hot);
+
+ /*
+ * mark its power state as "unknown", since we don't know if
+ * e.g. the BIOS will change its device state when we suspend.
+ */
+ dev->current_state = PCI_UNKNOWN;
+}
+
static int pci_device_suspend(struct device * dev, pm_message_t state)
{
struct pci_dev * pci_dev = to_pci_dev(dev);
@@ -274,13 +296,7 @@ static int pci_device_suspend(struct device * dev, pm_message_t state)
i = drv->suspend(pci_dev, state);
suspend_report_result(drv->suspend, i);
} else {
- pci_save_state(pci_dev);
- /*
- * mark its power state as "unknown", since we don't know if
- * e.g. the BIOS will change its device state when we suspend.
- */
- if (pci_dev->current_state == PCI_D0)
- pci_dev->current_state = PCI_UNKNOWN;
+ pci_default_suspend(pci_dev, state);
}
return i;
}
@@ -294,6 +310,8 @@ static int pci_device_suspend_late(struct device * dev, pm_message_t state)
if (drv && drv->suspend_late) {
i = drv->suspend_late(pci_dev, state);
suspend_report_result(drv->suspend_late, i);
+ } else {
+ pci_default_suspend_late(pci_dev, state);
}
return i;
}
On Monday 24 December 2007 18:34:21 Linus Torvalds wrote:
> On Mon, 24 Dec 2007, Rafael J. Wysocki wrote:
> > Well, having considered that for a longer while, I think the AML code is
> > referring to a device that we have suspended already, and since it's in a
> > low power state, it just can't handle the reference.
> >
> > If that is the case, we'll have to find the device (that should be
> > possible using some code instrumentation) and move the suspending of it
> > into the late stage.
>
> Yes.
My own experimentation (in device_suspend(), calling _PTS() in the AML after
each suspend_device() runs, until one device causes it to hang) points to
ohci_hcd being the culprit here (with or without any devices attached). With
the ohci_hcd module unloaded, the machine suspends just fine[1].
Of course, I'm at a complete loss as to why suspending OHCI would cause a
problem for an IO port write.
> NOTE! This following patch is just for discussion, and while I think it's
> conceptually a good thing to try, I don't think it will help Carlos'
> problem. But removing the "pci_set_power_state()" in agp_nvidia_suspend()
> might.
nvidia-agp cannot be built on x86-64, so it's not the culprit in this case.
-Carlos
[1] And yes, I double checked the custom DSDT is not loaded this time.
--
E-Mail: [email protected]
Web: strangeworlds.co.uk
GPG Key ID: 0x23EE722D
Hi!
> On Sunday, 23 of December 2007, Carlos Corbacho wrote:
> > Fix suspend-to-RAM on nForce 4 (CK804) boards by increasing
> > PCIBIOS_MIN_IO.
> >
> > Fixes kernel bugzilla #9528
> >
> > Problem:
> >
> > Linus' patch (52ade9b3b97fd3bea42842a056fe0786c28d0555) to re-order
> > suspend (and fix fall out from Rafael's earlier suspend reordering work)
> > broke suspend-to-RAM on nForce 4 (CK804) boards.
> >
> > Why:
> >
> > After debugging _PTS() in the DSDT, it turns out these nVidia boards are
> > trying to write to an IO port > 0x1000 (0x142E) during suspend. Before the
> > re-ordering, we got away with this.
> >
> > After the afore mentioned commit, we started hitting the PCIBIOS_MIN_IO
> > limit and suspend then broke on these machines (the machine simply hangs
> > when it reaches the 0x142E IO port write during suspend-to-RAM).
> >
> > There was some previous work in the PCIBIOS_MIN_IO area over two years ago
> > (71db63acff69618b3d9d3114bd061938150e146b) which bumped this to 0x4000,
> > but this was reverted (2ba84684e8cf6f980e4e95a2300f53a505eb794e) after
> > causing new and entirely different problems on another nForce board.
> >
> > 0x1500 has been picked here as a nice, round and more conservative value
> > than 0x4000, and which covers 0x142E.
>
> The patch is fine by me, so if anyone has objections, please speak up.
Just.. I have been running with very similar patch for few years... it
fixes few prototype machines I have here.
> > diff --git a/include/asm-x86/pci.h b/include/asm-x86/pci.h
> > index e883619..03cb123 100644
> > --- a/include/asm-x86/pci.h
> > +++ b/include/asm-x86/pci.h
> > @@ -46,7 +46,7 @@ extern unsigned int pcibios_assign_all_busses(void);
> > #define pcibios_scan_all_fns(a, b) 0
> >
> > extern unsigned long pci_mem_start;
> > -#define PCIBIOS_MIN_IO 0x1000
> > +#define PCIBIOS_MIN_IO 0x1500
> > #define PCIBIOS_MIN_MEM (pci_mem_start)
> >
> > #define PCIBIOS_MIN_CARDBUS_IO 0x4000
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
Pavel,
On Tuesday 25 December 2007 12:12:31 Pavel Machek wrote:
> > The patch is fine by me, so if anyone has objections, please speak up.
>
> Just.. I have been running with very similar patch for few years... it
> fixes few prototype machines I have here.
I've withdrawn the patch since it doesn't actually fix the issue (turns out
it's actually a bug in Linux's handling of suspend-to-RAM for ACPI 1.0 and
2.0 systems).
-Carlos
--
E-Mail: [email protected]
Web: strangeworlds.co.uk
GPG Key ID: 0x23EE722D
On Monday, 24 of December 2007, Linus Torvalds wrote:
>
> On Mon, 24 Dec 2007, Rafael J. Wysocki wrote:
> >
> > Well, having considered that for a longer while, I think the AML code is
> > referring to a device that we have suspended already, and since it's in a low
> > power state, it just can't handle the reference.
> >
> > If that is the case, we'll have to find the device (that should be possible
> > using some code instrumentation) and move the suspending of it into the late
> > stage.
>
> Yes.
>
> In general, I'm personally of the opinion that drivers should *not*
> actually go into D3 at all in the regular "->suspend()" phase. It should
> be done in ->suspend_late. The early suspend is for saving state and
> returning errors.
>
> Sadly, we've made it a bit too inconvenient to actually do that. Almost
> all drivers only do the "->suspend" thing, and the default PCI behaviour
> doesn't help us in any way either.
>
> Anyway, I wonder if a patch like this could make it easier for driver
> writers to handle things. It basically does:
>
> - if you don't have a regular "suspend()" function, we'll just save state
> at suspend time.
>
> - if you don't have a "suspend_late()" function, we'll look at the
> current state, and if it's still in PCI_D0, we'll suspend to PCI_D3hot
> if it's a regular PCI device (ie not a bridge or something else odd).
>
> - then, at resume time, by default we don't do anything in the early
> resume, but in the late resume we'll undo everything, of course.
>
> Anyway, with this, most drivers could just remove the
> "pci_set_power_state()" call *entirely*, and let the default
> suspend_late action power the device down. But if you want to override
> that default action, you can either:
>
> - set the power state in your own ->suspend() routine (either by using
> pci_set_power_state(), or by just explicitly setting the state to
> unknown with "dev->current_state = PCI_UNKNOWN"
>
> - have a "late_suspend()" action, which obviously will override the
> default action entirely.
>
> Hmm?
Well, as Carlos correctly noticed, the problem is related to the change in
the ACPI specification between versions 1.0x and 2.0. Namely, while ACPI
2.0 and later wants us to put devices into low power states before calling
_PTS, ACPI 1.0x wants us to do that after calling _PTS. Since we're following
the 2.0 and later specifications right now, we're not doing the right thing for
the (strictly) ACPI 1.0x-compliant systems.
We ought to be able to fix things on the high level, by calling _PTS earlier on
systems that claim to be ACPI 1.0x-compliant. That will require us to modify
the generic susped code quite a bit and will need to be tested for some time.
I'm going to prepare patches to implement this idea targeted for the 2.6.25
time frame.
Greetings,
Rafael
On Tue, 25 Dec 2007, Rafael J. Wysocki wrote:
>
> the ACPI specification between versions 1.0x and 2.0. Namely, while ACPI
> 2.0 and later wants us to put devices into low power states before calling
> _PTS, ACPI 1.0x wants us to do that after calling _PTS. Since we're following
> the 2.0 and later specifications right now, we're not doing the right thing for
> the (strictly) ACPI 1.0x-compliant systems.
>
> We ought to be able to fix things on the high level, by calling _PTS earlier on
> systems that claim to be ACPI 1.0x-compliant. That will require us to modify
> the generic susped code quite a bit and will need to be tested for some time.
That's insane. Are you really saying that ACPI wants totally different
orderings for different versions of the spec? And does Windows really do
that?
Please don't make lots of modifications to the generic suspend code. The
only thing that is worth doing is to just have a firmware callback before
the "device_suspend()" thing (and then on a ACPI-1.0 system, call _PTS
*there*), and on an ACPI-2.0 system, call _PTS *after* device_suspend().
Still, the fact is, some (most, I think) drivers *should* put themselves
into D3 only in "late_suspend()", so if ACPI-2.0 really expects _PTS to be
called after that, we're just screwed. That's when the system is really
down, interrupts disabled etc, we don't want to call anything but the
final ACPI "turn us off" stuff there!
Linus
On Wednesday, 26 of December 2007, Linus Torvalds wrote:
>
> On Tue, 25 Dec 2007, Rafael J. Wysocki wrote:
> >
> > the ACPI specification between versions 1.0x and 2.0. Namely, while ACPI
> > 2.0 and later wants us to put devices into low power states before calling
> > _PTS, ACPI 1.0x wants us to do that after calling _PTS. Since we're following
> > the 2.0 and later specifications right now, we're not doing the right thing for
> > the (strictly) ACPI 1.0x-compliant systems.
> >
> > We ought to be able to fix things on the high level, by calling _PTS earlier on
> > systems that claim to be ACPI 1.0x-compliant. That will require us to modify
> > the generic susped code quite a bit and will need to be tested for some time.
>
> That's insane. Are you really saying that ACPI wants totally different
> orderings for different versions of the spec?
Yes, I am.
> And does Windows really do that?
I don't know.
> Please don't make lots of modifications to the generic suspend code. The
> only thing that is worth doing is to just have a firmware callback before
> the "device_suspend()" thing (and then on a ACPI-1.0 system, call _PTS
> *there*), and on an ACPI-2.0 system, call _PTS *after* device_suspend().
Yes, that's what I'm going to do, but I need to untangle some ACPI code for
this purpose.
> Still, the fact is, some (most, I think) drivers *should* put themselves
> into D3 only in "late_suspend()", so if ACPI-2.0 really expects _PTS to be
> called after that, we're just screwed.
Well, section 9.1.6 of ACPI 2.0 specifies the suspend ordering directly and
says exactly that _PTS is to be executed after putting devices into respective
D states.
> That's when the system is really down, interrupts disabled etc, we don't want
> to call anything but the final ACPI "turn us off" stuff there!
OTOH, we ought to be able to put devices into low power states at any time, for
example when they are not used, without any problems and having to put them
back into D0 just in order to execute _PTS doesn't seem very logical to me. ;-)
Greetings,
Rafael
Rafael J. Wysocki wrote:
> On Wednesday, 26 of December 2007, Linus Torvalds wrote:
>
>> On Tue, 25 Dec 2007, Rafael J. Wysocki wrote:
>>
>>> the ACPI specification between versions 1.0x and 2.0. Namely, while ACPI
>>> 2.0 and later wants us to put devices into low power states before calling
>>> _PTS, ACPI 1.0x wants us to do that after calling _PTS. Since we're following
>>> the 2.0 and later specifications right now, we're not doing the right thing for
>>> the (strictly) ACPI 1.0x-compliant systems.
>>>
>>> We ought to be able to fix things on the high level, by calling _PTS earlier on
>>> systems that claim to be ACPI 1.0x-compliant. That will require us to modify
>>> the generic susped code quite a bit and will need to be tested for some time.
>>>
>> That's insane. Are you really saying that ACPI wants totally different
>> orderings for different versions of the spec?
>>
>
> Yes, I am.
>
>
>> And does Windows really do that?
>>
>
> I don't know.
>
Windows was compliant only with 1.x spec until Vista.
With Vista claims are 3.x compliance.
Alexey Starikovskiy wrote:
>>
>> I don't know.
>>
> Windows was compliant only with 1.x spec until Vista.
> With Vista claims are 3.x compliance.
>
In other words, the 1.x spec is the only thing that matters, at least in
the short term (*noone* is giving up XP compatibility at this point.)
-hpa