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Diffstat (limited to 'include/linux/clocksource.h')
-rw-r--r--include/linux/clocksource.h30
1 files changed, 18 insertions, 12 deletions
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 08398182f56e..cfc75848a35d 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -62,6 +62,8 @@ struct module;
* @archdata: arch-specific data
* @suspend: suspend function for the clocksource, if necessary
* @resume: resume function for the clocksource, if necessary
+ * @mark_unstable: Optional function to inform the clocksource driver that
+ * the watchdog marked the clocksource unstable
* @owner: module reference, must be set by clocksource in modules
*
* Note: This struct is not used in hotpathes of the timekeeping code
@@ -75,8 +77,8 @@ struct module;
* structure.
*/
struct clocksource {
- cycle_t (*read)(struct clocksource *cs);
- cycle_t mask;
+ u64 (*read)(struct clocksource *cs);
+ u64 mask;
u32 mult;
u32 shift;
u64 max_idle_ns;
@@ -93,13 +95,14 @@ struct clocksource {
unsigned long flags;
void (*suspend)(struct clocksource *cs);
void (*resume)(struct clocksource *cs);
+ void (*mark_unstable)(struct clocksource *cs);
/* private: */
#ifdef CONFIG_CLOCKSOURCE_WATCHDOG
/* Watchdog related data, used by the framework */
struct list_head wd_list;
- cycle_t cs_last;
- cycle_t wd_last;
+ u64 cs_last;
+ u64 wd_last;
#endif
struct module *owner;
};
@@ -117,7 +120,7 @@ struct clocksource {
#define CLOCK_SOURCE_RESELECT 0x100
/* simplify initialization of mask field */
-#define CLOCKSOURCE_MASK(bits) (cycle_t)((bits) < 64 ? ((1ULL<<(bits))-1) : -1)
+#define CLOCKSOURCE_MASK(bits) (u64)((bits) < 64 ? ((1ULL<<(bits))-1) : -1)
static inline u32 clocksource_freq2mult(u32 freq, u32 shift_constant, u64 from)
{
@@ -169,11 +172,14 @@ static inline u32 clocksource_hz2mult(u32 hz, u32 shift_constant)
* @mult: cycle to nanosecond multiplier
* @shift: cycle to nanosecond divisor (power of two)
*
- * Converts cycles to nanoseconds, using the given mult and shift.
+ * Converts clocksource cycles to nanoseconds, using the given @mult and @shift.
+ * The code is optimized for performance and is not intended to work
+ * with absolute clocksource cycles (as those will easily overflow),
+ * but is only intended to be used with relative (delta) clocksource cycles.
*
* XXX - This could use some mult_lxl_ll() asm optimization
*/
-static inline s64 clocksource_cyc2ns(cycle_t cycles, u32 mult, u32 shift)
+static inline s64 clocksource_cyc2ns(u64 cycles, u32 mult, u32 shift)
{
return ((u64) cycles * mult) >> shift;
}
@@ -233,13 +239,13 @@ static inline void __clocksource_update_freq_khz(struct clocksource *cs, u32 khz
extern int timekeeping_notify(struct clocksource *clock);
-extern cycle_t clocksource_mmio_readl_up(struct clocksource *);
-extern cycle_t clocksource_mmio_readl_down(struct clocksource *);
-extern cycle_t clocksource_mmio_readw_up(struct clocksource *);
-extern cycle_t clocksource_mmio_readw_down(struct clocksource *);
+extern u64 clocksource_mmio_readl_up(struct clocksource *);
+extern u64 clocksource_mmio_readl_down(struct clocksource *);
+extern u64 clocksource_mmio_readw_up(struct clocksource *);
+extern u64 clocksource_mmio_readw_down(struct clocksource *);
extern int clocksource_mmio_init(void __iomem *, const char *,
- unsigned long, int, unsigned, cycle_t (*)(struct clocksource *));
+ unsigned long, int, unsigned, u64 (*)(struct clocksource *));
extern int clocksource_i8253_init(void);