Add syslib function to obtain CPU frequency

diff --git a/include/minix/sysutil.h b/include/minix/sysutil.h
index c6e4edb336e5d855f7eee1aeaeb7cddba2fdc2c0..e596e9635d97fbad567565a23f2c6aa662946857 100644 (file)
--- a/include/minix/sysutil.h
+++ b/include/minix/sysutil.h
@@ -57,6 +57,7 @@ _PROTOTYPE( void util_stacktrace_strcat, (char *));
 _PROTOTYPE( int micro_delay, (u32_t micros));
 _PROTOTYPE( u32_t tsc_64_to_micros, (u64_t tsc));
 _PROTOTYPE( u32_t tsc_to_micros, (u32_t low, u32_t high));
+_PROTOTYPE( u32_t tsc_get_khz, (void));
 _PROTOTYPE( u32_t micros_to_ticks, (u32_t micros));
 _PROTOTYPE( void ser_putc, (char c));
 _PROTOTYPE( void get_randomness, (struct k_randomness *, int));

diff --git a/lib/libsys/tsc_util.c b/lib/libsys/tsc_util.c
index dfb1218e065e2ce2faf23133210629e2618395d4..815d8840f58265ed2217231e9cf34570db9fd8de 100644 (file)
--- a/lib/libsys/tsc_util.c
+++ b/lib/libsys/tsc_util.c
@@ -111,3 +111,9 @@ u32_t tsc_to_micros(u32_t low, u32_t high)
        return micros;
 }
 
+u32_t tsc_get_khz(void)
+{
+       CALIBRATE;
+
+       return calib_tsc / (CALIBRATE_TICKS(Hz) * MICROSPERTICK(Hz)) * 1000;
+}