x86: HPET force enable for ICH5

force_enable hpet for ICH5.

[ Build fixes from Andrew Morton ]

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c
index d3ac703..79133b1 100644
--- a/arch/x86/kernel/quirks.c
+++ b/arch/x86/kernel/quirks.c
@@ -53,9 +53,15 @@
 #if defined(CONFIG_HPET_TIMER)
 unsigned long force_hpet_address;
 
+static enum {
+	NONE_FORCE_HPET_RESUME,
+	OLD_ICH_FORCE_HPET_RESUME,
+	ICH_FORCE_HPET_RESUME
+} force_hpet_resume_type;
+
 static void __iomem *rcba_base;
 
-void ich_force_hpet_resume(void)
+static void ich_force_hpet_resume(void)
 {
 	u32 val;
 
@@ -133,6 +139,7 @@
 		iounmap(rcba_base);
 		printk(KERN_DEBUG "Failed to force enable HPET\n");
 	} else {
+		force_hpet_resume_type = ICH_FORCE_HPET_RESUME;
 		printk(KERN_DEBUG "Force enabled HPET at base address 0x%lx\n",
 			       force_hpet_address);
 	}
@@ -148,4 +155,98 @@
                          ich_force_enable_hpet);
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH8_1,
                          ich_force_enable_hpet);
+
+
+static struct pci_dev *cached_dev;
+
+static void old_ich_force_hpet_resume(void)
+{
+	u32 val;
+	u32 uninitialized_var(gen_cntl);
+
+	if (!force_hpet_address || !cached_dev)
+		return;
+
+	pci_read_config_dword(cached_dev, 0xD0, &gen_cntl);
+	gen_cntl &= (~(0x7 << 15));
+	gen_cntl |= (0x4 << 15);
+
+	pci_write_config_dword(cached_dev, 0xD0, gen_cntl);
+	pci_read_config_dword(cached_dev, 0xD0, &gen_cntl);
+	val = gen_cntl >> 15;
+	val &= 0x7;
+	if (val == 0x4)
+		printk(KERN_DEBUG "Force enabled HPET at resume\n");
+	else
+		BUG();
+}
+
+static void old_ich_force_enable_hpet(struct pci_dev *dev)
+{
+	u32 val;
+	u32 uninitialized_var(gen_cntl);
+
+	if (hpet_address || force_hpet_address)
+		return;
+
+	pci_read_config_dword(dev, 0xD0, &gen_cntl);
+	/*
+	 * Bit 17 is HPET enable bit.
+	 * Bit 16:15 control the HPET base address.
+	 */
+	val = gen_cntl >> 15;
+	val &= 0x7;
+	if (val & 0x4) {
+		val &= 0x3;
+		force_hpet_address = 0xFED00000 | (val << 12);
+		printk(KERN_DEBUG "HPET at base address 0x%lx\n",
+			       force_hpet_address);
+		cached_dev = dev;
+		return;
+	}
+
+	/*
+	 * HPET is disabled. Trying enabling at FED00000 and check
+	 * whether it sticks
+	 */
+	gen_cntl &= (~(0x7 << 15));
+	gen_cntl |= (0x4 << 15);
+	pci_write_config_dword(dev, 0xD0, gen_cntl);
+
+	pci_read_config_dword(dev, 0xD0, &gen_cntl);
+
+	val = gen_cntl >> 15;
+	val &= 0x7;
+	if (val & 0x4) {
+		/* HPET is enabled in HPTC. Just not reported by BIOS */
+		val &= 0x3;
+		force_hpet_address = 0xFED00000 | (val << 12);
+		printk(KERN_DEBUG "Force enabled HPET at base address 0x%lx\n",
+			       force_hpet_address);
+		force_hpet_resume_type = OLD_ICH_FORCE_HPET_RESUME;
+		return;
+	}
+
+	printk(KERN_DEBUG "Failed to force enable HPET\n");
+}
+
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_0,
+                         old_ich_force_enable_hpet);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_12,
+                         old_ich_force_enable_hpet);
+
+void force_hpet_resume(void)
+{
+	switch (force_hpet_resume_type) {
+	    case ICH_FORCE_HPET_RESUME:
+		return ich_force_hpet_resume();
+
+	    case OLD_ICH_FORCE_HPET_RESUME:
+		return old_ich_force_hpet_resume();
+
+	    default:
+		break;
+	}
+}
+
 #endif