1 files changed, 32 insertions, 8 deletions

diff --git a/drivers/clocksource/timer-sp804.c b/drivers/clocksource/timer-sp804.c
index 401d592e85f5..e82a95ea4724 100644
--- a/drivers/clocksource/timer-sp804.c
+++ b/drivers/clocksource/timer-sp804.c
@@ -21,6 +21,10 @@
 #include <linux/of_irq.h>
 #include <linux/sched_clock.h>
 
+#ifdef CONFIG_ARM
+#include <linux/delay.h>
+#endif
+
 #include "timer-sp.h"
 
 /* Hisilicon 64-bit timer(a variant of ARM SP804) */
@@ -102,6 +106,23 @@ static u64 notrace sp804_read(void)
 	return ~readl_relaxed(sched_clkevt->value);
 }
 
+#ifdef CONFIG_ARM
+static struct delay_timer delay;
+static unsigned long sp804_read_delay_timer_read(void)
+{
+	return sp804_read();
+}
+
+static void sp804_register_delay_timer(int freq)
+{
+	delay.freq = freq;
+	delay.read_current_timer = sp804_read_delay_timer_read;
+	register_current_timer_delay(&delay);
+}
+#else
+static inline void sp804_register_delay_timer(int freq) {}
+#endif
+
 static int __init sp804_clocksource_and_sched_clock_init(void __iomem *base,
 							 const char *name,
 							 struct clk *clk,
@@ -114,6 +135,8 @@ static int __init sp804_clocksource_and_sched_clock_init(void __iomem *base,
 	if (rate < 0)
 		return -EINVAL;
 
+	sp804_register_delay_timer(rate);
+
 	clkevt = sp804_clkevt_get(base);
 
 	writel(0, clkevt->ctrl);
@@ -155,14 +178,14 @@ static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static inline void timer_shutdown(struct clock_event_device *evt)
+static inline void evt_timer_shutdown(struct clock_event_device *evt)
 {
 	writel(0, common_clkevt->ctrl);
 }
 
 static int sp804_shutdown(struct clock_event_device *evt)
 {
-	timer_shutdown(evt);
+	evt_timer_shutdown(evt);
 	return 0;
 }
 
@@ -171,7 +194,7 @@ static int sp804_set_periodic(struct clock_event_device *evt)
 	unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
 			     TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
 
-	timer_shutdown(evt);
+	evt_timer_shutdown(evt);
 	writel(common_clkevt->reload, common_clkevt->load);
 	writel(ctrl, common_clkevt->ctrl);
 	return 0;
@@ -259,6 +282,11 @@ static int __init sp804_of_init(struct device_node *np, struct sp804_timer *time
 	struct clk *clk1, *clk2;
 	const char *name = of_get_property(np, "compatible", NULL);
 
+	if (initialized) {
+		pr_debug("%pOF: skipping further SP804 timer device\n", np);
+		return 0;
+	}
+
 	base = of_iomap(np, 0);
 	if (!base)
 		return -ENXIO;
@@ -270,11 +298,6 @@ static int __init sp804_of_init(struct device_node *np, struct sp804_timer *time
 	writel(0, timer1_base + timer->ctrl);
 	writel(0, timer2_base + timer->ctrl);
 
-	if (initialized || !of_device_is_available(np)) {
-		ret = -EINVAL;
-		goto err;
-	}
-
 	clk1 = of_clk_get(np, 0);
 	if (IS_ERR(clk1))
 		clk1 = NULL;
@@ -318,6 +341,7 @@ static int __init sp804_of_init(struct device_node *np, struct sp804_timer *time
 		if (ret)
 			goto err;
 	}
+
 	initialized = true;
 
 	return 0;