ARCv2: clocksource: Introduce 64bit local RTC counter
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c
index 71493f7..da49547 100644
--- a/arch/arc/kernel/time.c
+++ b/arch/arc/kernel/time.c
@@ -60,6 +60,54 @@
/********** Clock Source Device *********/
+#ifdef CONFIG_ARC_HAS_RTC
+
+#define AUX_RTC_CTRL 0x103
+#define AUX_RTC_LOW 0x104
+#define AUX_RTC_HIGH 0x105
+
+int arc_counter_setup(void)
+{
+ write_aux_reg(AUX_RTC_CTRL, 1);
+
+ /* Not usable in SMP */
+ return !IS_ENABLED(CONFIG_SMP);
+}
+
+static cycle_t arc_counter_read(struct clocksource *cs)
+{
+ unsigned long status;
+ union {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+ struct { u32 high, low; };
+#else
+ struct { u32 low, high; };
+#endif
+ cycle_t full;
+ } stamp;
+
+
+ __asm__ __volatile(
+ "1: \n"
+ " lr %0, [AUX_RTC_LOW] \n"
+ " lr %1, [AUX_RTC_HIGH] \n"
+ " lr %2, [AUX_RTC_CTRL] \n"
+ " bbit0.nt %2, 31, 1b \n"
+ : "=r" (stamp.low), "=r" (stamp.high), "=r" (status));
+
+ return stamp.full;
+}
+
+static struct clocksource arc_counter = {
+ .name = "ARCv2 RTC",
+ .rating = 350,
+ .read = arc_counter_read,
+ .mask = CLOCKSOURCE_MASK(64),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+#else /* !CONFIG_ARC_HAS_RTC */
+
/*
* set 32bit TIMER1 to keep counting monotonically and wraparound
*/
@@ -86,6 +134,8 @@
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
+#endif
+
/********** Clock Event Device *********/
/*