Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/sc…

…m/linux/kernel/git/tip/tip

Pull timer fixes from Thomas Gleixner:
 "The following trilogy of patches brings you:

   - fix for a long standing math overflow issue with HZ < 60

   - an onliner fix for a corner case in the dreaded tick broadcast
     mechanism affecting a certain range of AMD machines which are
     infested with the infamous automagic C1E power control misfeature

   - a fix for one of the ARM platforms which allows the kernel to
     proceed and boot instead of stupidly panicing for no good reason.
     The patch is slightly larger than necessary, but it's less ugly
     than the alternative 5 liner"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick: Clear broadcast pending bit when switching to oneshot
  clocksource: Kona: Print warning rather than panic
  time: Fix overflow when HZ is smaller than 60

drivers/clocksource/bcm_kona_timer.c

@@ -99,31 +99,6 @@ kona_timer_get_counter(void *timer_base, uint32_t *msw, uint32_t *lsw)
 	return;
 }
 
-static void __init kona_timers_init(struct device_node *node)
-{
-	u32 freq;
-	struct clk *external_clk;
-
-	external_clk = of_clk_get_by_name(node, NULL);
-
-	if (!IS_ERR(external_clk)) {
-		arch_timer_rate = clk_get_rate(external_clk);
-		clk_prepare_enable(external_clk);
-	} else if (!of_property_read_u32(node, "clock-frequency", &freq)) {
-		arch_timer_rate = freq;
-	} else {
-		panic("unable to determine clock-frequency");
-	}
-
-	/* Setup IRQ numbers */
-	timers.tmr_irq = irq_of_parse_and_map(node, 0);
-
-	/* Setup IO addresses */
-	timers.tmr_regs = of_iomap(node, 0);
-
-	kona_timer_disable_and_clear(timers.tmr_regs);
-}
-
 static int kona_timer_set_next_event(unsigned long clc,
 				  struct clock_event_device *unused)
 {
@@ -198,7 +173,34 @@ static struct irqaction kona_timer_irq = {
 
 static void __init kona_timer_init(struct device_node *node)
 {
-	kona_timers_init(node);
+	u32 freq;
+	struct clk *external_clk;
+
+	if (!of_device_is_available(node)) {
+		pr_info("Kona Timer v1 marked as disabled in device tree\n");
+		return;
+	}
+
+	external_clk = of_clk_get_by_name(node, NULL);
+
+	if (!IS_ERR(external_clk)) {
+		arch_timer_rate = clk_get_rate(external_clk);
+		clk_prepare_enable(external_clk);
+	} else if (!of_property_read_u32(node, "clock-frequency", &freq)) {
+		arch_timer_rate = freq;
+	} else {
+		pr_err("Kona Timer v1 unable to determine clock-frequency");
+		return;
+	}
+
+	/* Setup IRQ numbers */
+	timers.tmr_irq = irq_of_parse_and_map(node, 0);
+
+	/* Setup IO addresses */
+	timers.tmr_regs = of_iomap(node, 0);
+
+	kona_timer_disable_and_clear(timers.tmr_regs);
+
 	kona_timer_clockevents_init();
 	setup_irq(timers.tmr_irq, &kona_timer_irq);
 	kona_timer_set_next_event((arch_timer_rate / HZ), NULL);

kernel/time/jiffies.c

@@ -51,7 +51,13 @@
  * HZ shrinks, so values greater than 8 overflow 32bits when
  * HZ=100.
  */
+#if HZ < 34
+#define JIFFIES_SHIFT	6
+#elif HZ < 67
+#define JIFFIES_SHIFT	7
+#else
 #define JIFFIES_SHIFT	8
+#endif
 
 static cycle_t jiffies_read(struct clocksource *cs)
 {

kernel/time/tick-broadcast.c

@@ -756,6 +756,7 @@ void tick_broadcast_oneshot_control(unsigned long reason)
 static void tick_broadcast_clear_oneshot(int cpu)
 {
 	cpumask_clear_cpu(cpu, tick_broadcast_oneshot_mask);
+	cpumask_clear_cpu(cpu, tick_broadcast_pending_mask);
 }
 
 static void tick_broadcast_init_next_event(struct cpumask *mask,