x86: HPET try to activate force detected hpet

Enable HPET later during boot, after the force detect in PCI quirks.  Also add
a call to repeat the force enabling at resume time.

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>

arch/x86/kernel/hpet.c

@@ -164,6 +164,7 @@ static struct clock_event_device hpet_clockevent = {
 	.set_next_event = hpet_legacy_next_event,
 	.shift		= 32,
 	.irq		= 0,
+	.rating		= 50,
 };
 
 static void hpet_start_counter(void)
@@ -178,6 +179,17 @@ static void hpet_start_counter(void)
 	hpet_writel(cfg, HPET_CFG);
 }
 
+static void hpet_resume_device(void)
+{
+	ich_force_hpet_resume();
+}
+
+static void hpet_restart_counter(void)
+{
+	hpet_resume_device();
+	hpet_start_counter();
+}
+
 static void hpet_enable_legacy_int(void)
 {
 	unsigned long cfg = hpet_readl(HPET_CFG);
@@ -299,7 +311,7 @@ static struct clocksource clocksource_hpet = {
 	.mask		= HPET_MASK,
 	.shift		= HPET_SHIFT,
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
-	.resume		= hpet_start_counter,
+	.resume		= hpet_restart_counter,
 #ifdef CONFIG_X86_64
 	.vread		= vread_hpet,
 #endif
@@ -412,10 +424,21 @@ int __init hpet_enable(void)
  */
 static __init int hpet_late_init(void)
 {
-	if (!is_hpet_capable())
+	if (boot_hpet_disable)
 		return -ENODEV;
 
+	if (!hpet_address) {
+		if (!force_hpet_address)
+			return -ENODEV;
+
+		hpet_address = force_hpet_address;
+		hpet_enable();
+		if (!hpet_virt_address)
+			return -ENODEV;
+	}
+
 	hpet_reserve_platform_timers(hpet_readl(HPET_ID));
+
 	return 0;
 }
 fs_initcall(hpet_late_init);

include/asm-x86/hpet.h

@@ -63,6 +63,7 @@
 
 /* hpet memory map physical address */
 extern unsigned long hpet_address;
+extern unsigned long force_hpet_address;
 extern int is_hpet_enabled(void);
 extern int hpet_enable(void);
 extern unsigned long hpet_readl(unsigned long a);