(Resend with CC's fixed)
Back in April, Mikko posted a patch to force enable the HPET on some nVidia

chipsets:
v2:

http://lkml.org/lkml/2007/4/16/46
v3:

http://lkml.org/lkml/2007/4/17/354
What would need to be done to this patch to get it into x86 now (besides i386/

x86_64 -> x86 conversion), given that:
A) There is now a force_hpet boot parameter in the x86 tree (mm branch)

(rather than relying on the solution in the earlier patches of a config

option).
B) On the other hand, the force-quirk's are going into quirks.c, whilst

Mikko's patch requires PCI scanning in early_quirks.c (could the PCI scanning

be done in early_quirks.c and the actual HPET enabling handled in quirks.c

later - or if not, could this early quirk play be made to obey the force_hpet

boot option)?
-Carlos

--

E-Mail: cathectic@gmail.com

Web: strangeworlds.co.uk

GPG Key ID: 0x23EE722D

-

There is still a config option for hpet. the hpet=force boot param is
It's not necessary to scan in early_quirks.c at all. The force hpet

code handles the late DECLARE_PCI_FIXUP_HEADER() based detection just

fine.
So if there are working quirks, please refactor them analogous to the

existing ones in quirks.c.
All undocumented chipset poking needs to be protected by the

hpet=force boot option, so the default is not to do scan for it.
Thanks,
        tglx

-

Thomas,
Would the following patch be more acceptable then? I've limited the device

id's to just the nForce 4 chipset, because that's the only one I have here

to test with at the moment - it appears to work fine:
hpet clockevent registered

hpet0: at MMIO 0xfefff000, IRQs 2, 8, 31

hpet0: 3 32-bit timers, 25000000 Hz

Time: hpet clocksource has been installed.

Switched to high resolution mode on CPU 0

Switched to high resolution mode on CPU 1
At the moment, I'm not clear on how to detect if the HPET has not been

enabled by the BIOS (but given that this is hidden behind hpet=force,

would this be acceptable, since the user would have to explicitly call

hpet=force, and then it either works or doesn't?)
-Carlos
diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c

index a4ce191..7c772bf 100644

--- a/arch/x86/kernel/quirks.c

+++ b/arch/x86/kernel/quirks.c

@@ -321,6 +321,26 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235,

 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237,

 			 vt8237_force_enable_hpet);
+static void nvidia_force_enable_hpet(struct pci_dev *dev)

+{

+	u32 uninitialized_var(val);

+

+	if (!hpet_force_user || hpet_address || force_hpet_address)

+		return;

+

+	pci_read_config_dword(dev, 0x44, &val);

+	force_hpet_address = val;

+	printk(KERN_DEBUG "Force enabled HPET at base address 0x%lx\n",

+	       force_hpet_address);

+	cached_dev = dev;

+	return;

+}

+

+/* ISA Bridge */

+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0050,

+			 nvidia_force_enable_hpet);

+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0051,

+			 nvidia_force_enable_hpet);
 void force_hpet_resume(void)

 {

-

Yes, looks good. It is just missing the resume part, which is
Don't worry. If HPET is enabled in the BIOS, then we have an

hpet_address already before we come into the force enable

quirk. That's why we check for hpet_address in the quirk code.
     tglx
-

From: Carlos Corbacho <cathectic@gmail.com>
This patch adds a quirk from LinuxBIOS to force enable HPET on

the nVidia CK804 (nForce 4) chipset.
This quirk can very likely support more than just nForce 4

(LinuxBIOS use the same code for nForce 5), and possibly nForce 3,

but I don't have those chipsets, so cannot add and test them.
Tested on an Abit KN9 (CK804).
Signed-off-by: Carlos Corbacho <cathectic@gmail.com>

---

Thomas,
I've rewritten the code based on what LinuxBIOS does, since they have a better idea

of how to drive the HPET than I do. I've tested this code, and it's also working

fine here on my system.
 Documentation/kernel-parameters.txt |    3 +-

 arch/x86/kernel/quirks.c            |   36 ++++++++++++++++++++++++++++++++++-

 2 files changed, 37 insertions(+), 2 deletions(-)
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt

index 983f631..8abbfe6 100644

--- a/Documentation/kernel-parameters.txt

+++ b/Documentation/kernel-parameters.txt

@@ -434,7 +434,8 @@ and is between 256 and 4096 characters. It is defined in the file

 	hpet=		[X86-32,HPET] option to control HPET usage

 			Format: { enable (default) | disable | force }

 			disable: disable HPET and use PIT instead

-			force: allow force enabled of undocumented chips (ICH4, VIA)

+			force: allow force enabled of undocumented chips (ICH4,

+			VIA, nVidia)
 	com20020=	[HW,NET] ARCnet - COM20020 chipset

 			Format:

diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c

index a4ce191..cb21bcb 100644

--- a/arch/x86/kernel/quirks.c

+++ b/arch/x86/kernel/quirks.c

@@ -60,7 +60,8 @@ static enum {

 	NONE_FORCE_HPET_RESUME,

 	OLD_ICH_FORCE_HPET_RESUME,

 	ICH_FORCE_HPET_RESUME,

-	VT8237_FORCE_HPET_RESUME

+	VT8237_FORCE_HPET_RESUME,

+	NVIDIA_FORCE_HPET_RESUME,

 } force_hpet_resume_type;
 static void __iomem *rcba_base;

@@ -321,6 +322,36 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235,

 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_...
[ message continues ]

Applied. Thanks,
	tglx

-

From: Carlos Corbacho <cathectic@gmail.com>
Actually set force_hpet_resume_type.

---

Whoops, just noticed I forgot to re-add this to the patch before submitting it.
 arch/x86/kernel/quirks.c |    1 +

 1 files changed, 1 insertions(+), 0 deletions(-)
diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c

index cb21bcb..df01a1e 100644

--- a/arch/x86/kernel/quirks.c

+++ b/arch/x86/kernel/quirks.c

@@ -344,6 +344,7 @@ static void nvidia_force_enable_hpet(struct pci_dev *dev)

 	printk(KERN_DEBUG "Force enabled HPET at base address 0x%lx\n",

 		force_hpet_address);

 	cached_dev = dev;

+	force_hpet_resume_type = NVIDIA_FORCE_HPET_RESUME;

 	return;

 }
--

1.5.2.2
-

Yep, noticed it when I pushed it into the queue. Fixed it up

already. Please be more careful next time.
Btw, I'm happy to take a follow up patch for platforms which you can

not test and stick them into -mm for a while.
Thanks,
	 tglx

-

From: Carlos Corbacho <cathectic@gmail.com>
Add support to force_hpet for all known MCP55 (nForce 5) chipset

LPC bridges.

---

These are the untested nForce 5 chips (taken from Mikko's original

patch, and checked against pci.ids).
 arch/x86/kernel/quirks.c |   18 ++++++++++++++++++

 1 files changed, 18 insertions(+), 0 deletions(-)
diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c

index df01a1e..8f72148 100644

--- a/arch/x86/kernel/quirks.c

+++ b/arch/x86/kernel/quirks.c

@@ -354,6 +354,24 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0050,

 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0051,

 			nvidia_force_enable_hpet);
+/* LPC bridges */

+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0360,

+			nvidia_force_enable_hpet);

+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0361,

+			nvidia_force_enable_hpet);

+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0362,

+			nvidia_force_enable_hpet);

+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0363,

+			nvidia_force_enable_hpet);

+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0364,

+			nvidia_force_enable_hpet);

+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0365,

+			nvidia_force_enable_hpet);

+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0366,

+			nvidia_force_enable_hpet);

+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA, 0x0367,

+			nvidia_force_enable_hpet);

+

 void force_hpet_resume(void)

 {

 	switch (force_hpet_resume_type) {

--

1.5.2.2
-