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* RE: [PATCH 1/5] RT kernel: force detect HPET from PCI space
@ 2007-03-30 16:50 Nicolas Mailhot
  2007-03-30 16:59 ` Venki Pallipadi
  0 siblings, 1 reply; 12+ messages in thread
From: Nicolas Mailhot @ 2007-03-30 16:50 UTC (permalink / raw)
  To: Venkatesh Pallipadi; +Cc: linux-kernel

Anyone got the same thing for CK804? I had my hopes high, and then I saw
the DECLARE_PCI_FIXUP_HEADER values [and the thread title was
misleading]

-- 
Nicolas Mailhot

^ permalink raw reply	[flat|nested] 12+ messages in thread
* RE: [PATCH 1/5] RT kernel: force detect HPET from PCI space
@ 2007-03-30 22:09 Mikko Tiihonen
  2007-03-30 22:38 ` Nicolas Mailhot
  0 siblings, 1 reply; 12+ messages in thread
From: Mikko Tiihonen @ 2007-03-30 22:09 UTC (permalink / raw)
  To: nicolas.mailhot; +Cc: linux-kernel


> Anyone got the same thing for CK804? I had my hopes high, and then I saw
> the DECLARE_PCI_FIXUP_HEADER values [and the thread title was misleading]

I have an A8N-E motherboard with AthlonX2 and the ACPI definitions are 
missing the HPET (standard feature of Asus motherboards).

I too got interested to get my motherboard working. Luckily I found this 
http://lkml.org/lkml/2006/12/17/69 from which I generated the following patch:

--- arch/i386/kernel/quirks.c.orig	2007-03-30 23:43:06.000000000 +0300
+++ arch/i386/kernel/quirks.c	2007-03-30 23:26:47.000000000 +0300
@@ -101,5 +101,39 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_I
  DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,   PCI_DEVICE_ID_INTEL_ICH7_1,     force_enable_hpet);
  DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,   PCI_DEVICE_ID_INTEL_ICH7_31,     force_enable_hpet);
  DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,   PCI_DEVICE_ID_INTEL_ICH8_1,     force_enable_hpet);
+
+static void __init force_enable_nvidia_hpet(struct pci_dev *dev)
+{
+        u8 enabled;
+	u32 addr;
+
+	if (hpet_address)
+		return;
+
+	pci_read_config_dword(dev, 0x44, &addr);
+	if (addr != 0xfefff000L) {
+		printk(KERN_INFO "Unsafe HPET address 0x%08x. Cannot force enable HPET\n", addr);
+		return;
+	}
+
+	pci_read_config_byte(dev, 0xA3, &enabled);
+	if ((enabled & 4) == 0) {
+	        if (enabled != 0xc1) {
+		  printk(KERN_INFO "Unsafe HPET enable 0x%02x. Cannot force enable HPET\n", enabled);
+		  return;
+		}
+		pci_write_config_byte(dev, 0xA3, enabled | 4);
+		pci_read_config_byte(dev, 0xA3, &enabled);
+		if ((enabled & 4) == 0) {
+			printk(KERN_INFO "Failed to force enable HPET\n");
+			return;
+		}
+	}
+
+	force_hpet_address = addr;
+	printk(KERN_INFO "Force enabled HPET. Base address 0x%08lx\n", force_hpet_address);
+}
+
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NVIDIA,	0x0050,     force_enable_nvidia_hpet); // NForce4
  #endif

Now Linux seems to detect HPET and it passes at least the basic sanity checks:

Force enabled HPET. Base address 0xfefff000
HPET: hpet_period 40000000, hpet_tick 83333
Successfully registered HPET clocksource

Unfortunately the 2.6.20-mm2 kernel to which I tried to patch the patch series 
seems to hang few seconds later after half way in udev startup event 
processing.

It could either be something totally different in 2.6.20-mm2 that just happens 
to fail or more likely some interrupt setup that still needs to be done.

I have no idea how to continue from here.

-Mikko

^ permalink raw reply	[flat|nested] 12+ messages in thread
* [PATCH 1/5] RT kernel: force detect HPET from PCI space
@ 2007-02-23  1:06 Venkatesh Pallipadi
  2007-03-30  9:46 ` Ingo Molnar
  0 siblings, 1 reply; 12+ messages in thread
From: Venkatesh Pallipadi @ 2007-02-23  1:06 UTC (permalink / raw)
  To: linux-kernel, Thomas Gleixner, Ingo Molnar



Patchset enables force detection of HPET, when it is not listed by BIOS.
and enables use of HPET as a event source. HPET timers
configures in stamdard interrupt mode can be used as dependable per CPU timer
on laptops that are known to have LAPIC stoppage with ACPI C3 state.

Patch is against rt kernel (2.6.20-rt8) and patch enables only x86-64
right now.

This patch:

Detect HPET by looking at PCI space, even when BIOS does not list HPET
device. This is useful to use HPET as dependable per CPU timer with tickless
kernels.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>

Index: linux-2.6.21-rc-mm/arch/i386/kernel/quirks.c
===================================================================
--- linux-2.6.21-rc-mm.orig/arch/i386/kernel/quirks.c
+++ linux-2.6.21-rc-mm/arch/i386/kernel/quirks.c
@@ -48,3 +48,58 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_IN
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_E7525_MCH,	quirk_intel_irqbalance);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_E7520_MCH,	quirk_intel_irqbalance);
 #endif
+
+#if defined(CONFIG_HPET_TIMER)
+unsigned long force_hpet_address;
+
+static void __init force_enable_hpet(struct pci_dev *dev)
+{
+	u32 val, rcba;
+	void __iomem *base;
+
+	if (hpet_address)
+		return;
+
+	pci_read_config_dword(dev, 0xF0, &rcba);
+	rcba &= 0xFFFFC000;
+	if (rcba == 0) {
+		printk(KERN_DEBUG "RCBA disabled. Cannot force enable HPET\n");
+		return;
+	}
+
+	/* use bits 31:14, 16 kB aligned */
+	base = ioremap_nocache(rcba, 0x4000);
+	if (base == NULL) {
+		printk(KERN_DEBUG "ioremap failed. Cannot force enable HPET\n");
+		return;
+	}
+
+	/* read the Function Disable register, dword mode only */
+	val = readl(base + 0x3404);
+
+	if (!(val & 0x80)) {
+		/* HPET disabled in HPTC. Trying to enable */
+		writel(val | 0x80, base + 0x3404);
+	}
+
+	val = readl(base + 0x3404);
+
+	if (!(val & 0x80)) {
+		printk(KERN_DEBUG "Failed to force enable HPET\n");
+	} else {
+		val = val & 0x3;
+		force_hpet_address = 0xFED00000 | (val << 12);
+		printk(KERN_DEBUG "Force enabled HPET. Base address 0x%x\n",
+			       force_hpet_address);
+	}
+
+	iounmap(base);
+}
+
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_ESB2_0,     force_enable_hpet);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,   PCI_DEVICE_ID_INTEL_ICH6_1,     force_enable_hpet);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,   PCI_DEVICE_ID_INTEL_ICH7_1,     force_enable_hpet);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,   PCI_DEVICE_ID_INTEL_ICH7_31,     force_enable_hpet);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,   PCI_DEVICE_ID_INTEL_ICH8_1,     force_enable_hpet);
+#endif
+
Index: linux-2.6.21-rc-mm/include/asm-i386/hpet.h
===================================================================
--- linux-2.6.21-rc-mm.orig/include/asm-i386/hpet.h
+++ linux-2.6.21-rc-mm/include/asm-i386/hpet.h
@@ -91,6 +91,7 @@
 #define HPET_TICK_RATE  (HZ * 100000UL)
 
 extern unsigned long hpet_address;	/* hpet memory map physical address */
+extern unsigned long force_hpet_address;/* hpet memory detected by quirk */
 extern int is_hpet_enabled(void);
 
 #ifdef CONFIG_X86_64
Index: linux-2.6.21-rc-mm/include/asm-x86_64/hpet.h
===================================================================
--- linux-2.6.21-rc-mm.orig/include/asm-x86_64/hpet.h
+++ linux-2.6.21-rc-mm/include/asm-x86_64/hpet.h
@@ -63,6 +63,7 @@ extern unsigned int hpet_calibrate_tsc(v
 
 extern int hpet_use_timer;
 extern unsigned long hpet_address;
+extern unsigned long force_hpet_address;
 extern unsigned long hpet_period;
 extern unsigned long hpet_tick;
 

^ permalink raw reply	[flat|nested] 12+ messages in thread
end of thread, other threads:[~2007-03-31 15:01 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2007-03-30 16:50 [PATCH 1/5] RT kernel: force detect HPET from PCI space Nicolas Mailhot
2007-03-30 16:59 ` Venki Pallipadi
2007-03-30 17:22   ` Nicolas Mailhot
  -- strict thread matches above, loose matches on Subject: below --
2007-03-30 22:09 Mikko Tiihonen
2007-03-30 22:38 ` Nicolas Mailhot
2007-03-31  8:00   ` Mikko Tiihonen
2007-03-31 10:37   ` Krzysztof Halasa
2007-03-31 11:36     ` Nicolas Mailhot
2007-03-31 15:00       ` Mikko Tiihonen
2007-02-23  1:06 Venkatesh Pallipadi
2007-03-30  9:46 ` Ingo Molnar
2007-03-30 13:36   ` Pallipadi, Venkatesh

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