1 files changed, 62 insertions, 0 deletions
diff --git a/packages/linux/linux-omap2-git/beagleboard/01-gptimer_maintain_tldr_lt_0xffffffff b/packages/linux/linux-omap2-git/beagleboard/01-gptimer_maintain_tldr_lt_0xffffffff
new file mode 100644
index 0000000000..ed62a6fb4b
--- /dev/null
+++ b/packages/linux/linux-omap2-git/beagleboard/01-gptimer_maintain_tldr_lt_0xffffffff
@@ -0,0 +1,62 @@
+3430 TRM 16.2.4.2 states:
+
+From: Paul Walmsley <paul@pwsan.com>
+
+Do not put the overflow value (0xFFFFFFFF) in the GPTi.TLDR register
+     because it can lead to undesired results.
+
+3430 TRM 16.2.4.7 states:
+
+     In the non-PWM mode, GTPi.TLDR must be maintained at less than or
+     equal to 0xFFFF FFFE.
+
+This patch contains some debugging code, and so is not yet intended for
+merging into linux-omap.
+---
+
+ arch/arm/mach-omap2/timer-gp.c |   17 ++++++++++++++++-
+ 1 files changed, 16 insertions(+), 1 deletions(-)
+
+diff --git a/arch/arm/mach-omap2/timer-gp.c b/arch/arm/mach-omap2/timer-gp.c
+index 557603f..edc0c9e 100644
+--- a/arch/arm/mach-omap2/timer-gp.c
++++ b/arch/arm/mach-omap2/timer-gp.c
+@@ -59,6 +59,11 @@ static struct irqaction omap2_gp_timer_irq = {
+ static int omap2_gp_timer_set_next_event(unsigned long cycles,
+ 					 struct clock_event_device *evt)
+ {
++	if (cycles == 0) {
++		pr_err("*** cycles = 0! fixing\n");
++		cycles = 1;
++	}
++
+ 	omap_dm_timer_set_load_start(gptimer, 0, 0xffffffff - cycles);
+ 
+ 	return 0;
+@@ -76,6 +81,15 @@ static void omap2_gp_timer_set_mode(enum clock_event_mode mode,
+ 		period = clk_get_rate(omap_dm_timer_get_fclk(gptimer)) / HZ;
+ 		period -= 1;
+ 
++		/* 
++		 * Unlikely that this will ever be hit since periodic
++		 * mode is rarely used 
++		 */
++		if (period == 0) {
++			pr_err("*** period = 0! fixing\n");
++			period = 1;
++		}
++
+ 		omap_dm_timer_set_load_start(gptimer, 1, 0xffffffff - period);
+ 		break;
+ 	case CLOCK_EVT_MODE_ONESHOT:
+@@ -117,8 +131,9 @@ static void __init omap2_gp_clockevent_init(void)
+ 				     clockevent_gpt.shift);
+ 	clockevent_gpt.max_delta_ns =
+ 		clockevent_delta2ns(0xffffffff, &clockevent_gpt);
++	/* per 3430 TRM table 16-11 */
+ 	clockevent_gpt.min_delta_ns =
+-		clockevent_delta2ns(1, &clockevent_gpt);
++		clockevent_delta2ns(2, &clockevent_gpt);
+ 
+ 	clockevent_gpt.cpumask = cpumask_of_cpu(0);
+ 	clockevents_register_device(&clockevent_gpt);