From b93d70aeb8f3b5ed2d74643f5009239a55634e1d Mon Sep 17 00:00:00 2001
From: Santosh Shilimkar <santosh.shilimkar@ti.com>
Date: Tue, 17 Apr 2012 15:09:20 +0530
Subject: ARM: OMAP4: CPUidle: Open broadcast clock-event device.

OMAP4 idle driver uses CLOCK_EVT_NOTIFY_BROADCAST_[ENTER/EXIT]
for broadcast clock events. But _ENTER/_EXIT doesn't really open
broadcast clock events and to explicitly setup the broadcast device,
CLOCK_EVT_NOTIFY_BROADCAST_ON should be used.

Add the missing CLOCK_EVT_NOTIFY_BROADCAST_ON clockevent notifications.
This will setup the broadcast timer in either periodic/oneshot modes
correctly. Recent clockevent infrastructure change 77b0d60 {leave the
broadcast device in shutdown mode when not needed} exposed this bug
leading to boot hangs in oneshot mode. Prior to this, periodic broadcast
mode was also broken. This change fixes both the periodic/oneshot broadcast
modes.

Discussion thread :
	https://lkml.org/lkml/2012/4/9/13

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
---
 arch/arm/mach-omap2/cpuidle44xx.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

(limited to 'arch/arm')

diff --git a/arch/arm/mach-omap2/cpuidle44xx.c b/arch/arm/mach-omap2/cpuidle44xx.c
index eb93e45d3271..45e6a54d5818 100644
--- a/arch/arm/mach-omap2/cpuidle44xx.c
+++ b/arch/arm/mach-omap2/cpuidle44xx.c
@@ -202,6 +202,16 @@ struct cpuidle_driver omap4_idle_driver = {
 	.safe_state_index = 0,
 };
 
+/*
+ * For each cpu, setup the broadcast timer because local timers
+ * stops for the states above C1.
+ */
+static void omap_setup_broadcast_timer(void *arg)
+{
+	int cpu = smp_processor_id();
+	clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ON, &cpu);
+}
+
 /**
  * omap4_idle_init - Init routine for OMAP4 idle
  *
@@ -224,6 +234,9 @@ int __init omap4_idle_init(void)
 	if (!cpu_clkdm[0] || !cpu_clkdm[1])
 		return -ENODEV;
 
+	/* Configure the broadcast timer on each cpu */
+	on_each_cpu(omap_setup_broadcast_timer, NULL, 1);
+
 	for_each_cpu(cpu_id, cpu_online_mask) {
 		dev = &per_cpu(omap4_idle_dev, cpu_id);
 		dev->cpu = cpu_id;
-- 
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