Add extra debug for the q_d_w_o() when work fn is already active.

From: Paul Walmsley <paul@pwsan.com>


---

 arch/arm/mach-omap2/timer-gp.c      |    3 ++-
 arch/arm/plat-omap/dmtimer.c        |   18 ++++++++++++++++++
 include/asm-arm/arch-omap/dmtimer.h |    1 +
 kernel/workqueue.c                  |   12 ++++++++++++
 4 files changed, 33 insertions(+), 1 deletions(-)

diff --git a/arch/arm/mach-omap2/timer-gp.c b/arch/arm/mach-omap2/timer-gp.c
index 869fe14..4db3252 100644
--- a/arch/arm/mach-omap2/timer-gp.c
+++ b/arch/arm/mach-omap2/timer-gp.c
@@ -37,6 +37,7 @@
 #include <asm/arch/dmtimer.h>
 
 static struct omap_dm_timer *gptimer;
+struct omap_dm_timer *gptimer_pub;
 static struct clock_event_device clockevent_gpt;
 
 static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
@@ -114,7 +115,7 @@ static void __init omap2_gp_clockevent_init(void)
 {
 	u32 tick_rate;
 
-	gptimer = omap_dm_timer_request_specific(1);
+	gptimer = gptimer_pub = omap_dm_timer_request_specific(1);
 	BUG_ON(gptimer == NULL);
 
 #if defined(CONFIG_OMAP_32K_TIMER)
diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c
index 4a5ada7..3242495 100644
--- a/arch/arm/plat-omap/dmtimer.c
+++ b/arch/arm/plat-omap/dmtimer.c
@@ -622,6 +622,24 @@ void omap_dm_timer_clear_ovf_cnt(struct omap_dm_timer *timer)
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_TICK_INT_MASK_SET_REG, 0);
 }
 
+void omap_dm_timer_dump_int_enable(struct omap_dm_timer *timer)
+{
+	u32 l;
+	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_COUNTER_REG);
+	pr_err("GPT TCRR: %08x\n", l);
+	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_STAT_REG);
+	pr_err("GPT TISR: %08x\n", l);
+	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_TICK_INT_MASK_SET_REG);
+	pr_err("GPT TOCR: %08x\n", l);
+	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_TICK_INT_MASK_COUNT_REG);
+	pr_err("GPT TOWR: %08x\n", l);
+	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_TICK_POS_REG);
+	pr_err("GPT TPIR: %08x\n", l);
+	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_TICK_NEG_REG);
+	pr_err("GPT TNIR: %08x\n", l);
+}
+
+
 unsigned int omap_dm_timer_read_status(struct omap_dm_timer *timer)
 {
 	unsigned int l;
diff --git a/include/asm-arm/arch-omap/dmtimer.h b/include/asm-arm/arch-omap/dmtimer.h
index 7b1138b..db57015 100644
--- a/include/asm-arm/arch-omap/dmtimer.h
+++ b/include/asm-arm/arch-omap/dmtimer.h
@@ -73,6 +73,7 @@ void omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler);
 
 void omap_dm_timer_set_int_enable(struct omap_dm_timer *timer, unsigned int value);
 
+void omap_dm_timer_dump_int_enable(struct omap_dm_timer *timer);
 void omap_dm_timer_clear_ovf_cnt(struct omap_dm_timer *timer);
 
 unsigned int omap_dm_timer_read_status(struct omap_dm_timer *timer);
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index ce77995..65b3b9a 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -33,6 +33,9 @@
 #include <linux/kallsyms.h>
 #include <linux/debug_locks.h>
 #include <linux/lockdep.h>
+#include <asm/arch/dmtimer.h>
+
+extern struct omap_dm_timer *gptimer_pub;
 
 /*
  * The per-CPU workqueue (if single thread, we always use the first
@@ -235,6 +238,15 @@ int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
 		else
 			add_timer(timer);
 		ret = 1;
+	} else {
+		s64 texp;
+		u64 now = ktime_to_ns(ktime_get());
+		u64 ens = jiffies_to_usecs(dwork->timer.expires) * 1000;
+		texp = ens - now;
+		if (texp < 0) {
+			pr_err("** Timer workaround\n");
+			omap_dm_timer_dump_int_enable(gptimer_pub);
+		}
 	}
 	return ret;
 }