Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6

[firefly-linux-kernel-4.4.55.git] / include / linux / time.h

diff --git a/include/linux/time.h b/include/linux/time.h
index 242f62499bb7bca6cd6c58fe134e7ffb8e97fa19..ea16c1a01d5188b3d9d39181d993d0c92508923b 100644 (file)
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -113,6 +113,21 @@ struct timespec current_kernel_time(void);
 #define CURRENT_TIME           (current_kernel_time())
 #define CURRENT_TIME_SEC       ((struct timespec) { get_seconds(), 0 })
 
+/* Some architectures do not supply their own clocksource.
+ * This is mainly the case in architectures that get their
+ * inter-tick times by reading the counter on their interval
+ * timer. Since these timers wrap every tick, they're not really
+ * useful as clocksources. Wrapping them to act like one is possible
+ * but not very efficient. So we provide a callout these arches
+ * can implement for use with the jiffies clocksource to provide
+ * finer then tick granular time.
+ */
+#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
+extern u32 arch_gettimeoffset(void);
+#else
+static inline u32 arch_gettimeoffset(void) { return 0; }
+#endif
+
 extern void do_gettimeofday(struct timeval *tv);
 extern int do_settimeofday(struct timespec *tv);
 extern int do_sys_settimeofday(struct timespec *tv, struct timezone *tz);