6 files changed, 9 insertions, 7 deletions

diff --git a/arch/i386/kernel/hpet.c b/arch/i386/kernel/hpet.c
index 23e7d2c5d253..c6737c35815d 100644
--- a/arch/i386/kernel/hpet.c
+++ b/arch/i386/kernel/hpet.c
@@ -6,7 +6,7 @@
 #include <asm/hpet.h>
 #include <asm/io.h>
 
-#define HPET_MASK       0xFFFFFFFF
+#define HPET_MASK       CLOCKSOURCE_MASK(32)
 #define HPET_SHIFT      22
 
 /* FSEC = 10^-15 NSEC = 10^-9 */
@@ -23,7 +23,7 @@ static struct clocksource clocksource_hpet = {
         .name           = "hpet",
         .rating         = 250,
         .read           = read_hpet,
-        .mask           = (cycle_t)HPET_MASK,
+        .mask           = HPET_MASK,
         .mult           = 0, /* set below */
         .shift          = HPET_SHIFT,
         .is_continuous  = 1,
diff --git a/arch/i386/kernel/i8253.c b/arch/i386/kernel/i8253.c
index 5b13739a7ff4..38aa7f19f1d3 100644
--- a/arch/i386/kernel/i8253.c
+++ b/arch/i386/kernel/i8253.c
@@ -69,7 +69,7 @@ static struct clocksource clocksource_pit = {
         .name   = "pit",
         .rating = 110,
         .read   = pit_read,
-        .mask   = (cycle_t)-1,
+        .mask   = CLOCKSOURCE_MASK(64),
         .mult   = 0,
         .shift  = 20,
 };
diff --git a/arch/i386/kernel/tsc.c b/arch/i386/kernel/tsc.c
index 1c3c927755de..7e0d8dab2075 100644
--- a/arch/i386/kernel/tsc.c
+++ b/arch/i386/kernel/tsc.c
@@ -337,7 +337,7 @@ static struct clocksource clocksource_tsc = {
         .name                   = "tsc",
         .rating                 = 300,
         .read                   = read_tsc,
-        .mask                   = (cycle_t)-1,
+        .mask                   = CLOCKSOURCE_MASK(64),
         .mult                   = 0, /* to be set */
         .shift                  = 22,
         .update_callback        = tsc_update_callback,
diff --git a/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c
index 066dc77433d5..7ad3be8c0f49 100644
--- a/drivers/clocksource/acpi_pm.c
+++ b/drivers/clocksource/acpi_pm.c
@@ -32,7 +32,7 @@
  */
 u32 pmtmr_ioport __read_mostly;
 
-#define ACPI_PM_MASK 0xFFFFFF /* limit it to 24 bits */
+#define ACPI_PM_MASK CLOCKSOURCE_MASK(24) /* limit it to 24 bits */
 
 static inline u32 read_pmtmr(void)
 {
diff --git a/drivers/clocksource/cyclone.c b/drivers/clocksource/cyclone.c
index 5906a0af825d..bf4d3d50d1c4 100644
--- a/drivers/clocksource/cyclone.c
+++ b/drivers/clocksource/cyclone.c
@@ -14,7 +14,7 @@
 #define CYCLONE_MPCS_OFFSET     0x51A8          /* offset to select register */
 #define CYCLONE_MPMC_OFFSET     0x51D0          /* offset to count register */
 #define CYCLONE_TIMER_FREQ      99780000        /* 100Mhz, but not really */
-#define CYCLONE_TIMER_MASK      0xFFFFFFFF      /* 32 bit mask */
+#define CYCLONE_TIMER_MASK      CLOCKSOURCE_MASK(32) /* 32 bit mask */
 
 int use_cyclone = 0;
 static void __iomem *cyclone_ptr;
@@ -28,7 +28,7 @@ static struct clocksource clocksource_cyclone = {
         .name           = "cyclone",
         .rating         = 250,
         .read           = read_cyclone,
-        .mask           = (cycle_t)CYCLONE_TIMER_MASK,
+        .mask           = CYCLONE_TIMER_MASK,
         .mult           = 10,
         .shift          = 0,
         .is_continuous  = 1,
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 5f4a7f72f3ee..4bc94282c364 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -65,6 +65,8 @@ struct clocksource {
         u64 interval_snsecs;
 };
 
+/* simplify initialization of mask field */
+#define CLOCKSOURCE_MASK(bits) (cycle_t)(bits<64 ? ((1ULL<<bits)-1) : -1)
 
 /**
  * clocksource_khz2mult - calculates mult from khz and shift