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>

1 files changed, 25 insertions, 2 deletions

diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index ce3bcc4334d5..a6c68915d2a9 100644
--- a/arch/x86/kernel/hpet.c
+++ b/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 @@ out_nohpet:
  */
 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);