[RESENT PATCH] Don't disable irqs in set_next_event and set_mode callbacks

[u.kleine-koenig@pengutronix.de (Uwe Kleine-König)]

These functions are called with irqs already off.

AT91RM2000 had a WARN_ON_ONCE if irqs were enabled since Nov 2008 with
noone reporting having hit it.

It should be safe to remove now.

Signed-off-by: Uwe Kleine-K?nig <u.kleine-koenig@pengutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Alessandro Rubini <rubini@unipv.it>
Cc: Andrea Gallo <andrea.gallo@stericsson.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: John Stultz <johnstul@us.ibm.com>
Acked-by: Kristoffer Ericson <Kristoffer.Ericson@gmail.com>
Cc: Magnus Damm <damm@igel.co.jp>
Cc: Nicolas Pitre <nico@marvell.com>
Cc: Remy Bohmer <linux@bohmer.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
---
Hello,

@Eric: You wrote you were not sure about this patch.  Would you prefer adding a
WARN_ON in a first step?

@Remy: You planned to test this back in September.  Did you?

Best regards
Uwe

 arch/arm/mach-at91/at91rm9200_time.c  |   14 --------------
 arch/arm/mach-at91/at91sam926x_time.c |    6 +-----
 arch/arm/mach-nomadik/timer.c         |    9 +--------
 arch/arm/mach-pxa/time.c              |   10 +---------
 arch/arm/mach-sa1100/time.c           |    8 +-------
 5 files changed, 4 insertions(+), 43 deletions(-)

diff --git a/arch/arm/mach-at91/at91rm9200_time.c b/arch/arm/mach-at91/at91rm9200_time.c
index 309f351..f27ccf6 100644
--- a/arch/arm/mach-at91/at91rm9200_time.c
+++ b/arch/arm/mach-at91/at91rm9200_time.c
@@ -132,24 +132,11 @@ clkevt32k_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 static int
 clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev)
 {
-	unsigned long	flags;
 	u32		alm;
 	int		status = 0;
 
 	BUG_ON(delta < 2);
 
-	/* Use "raw" primitives so we behave correctly on RT kernels. */
-	raw_local_irq_save(flags);
-
-	/*
-	 * According to Thomas Gleixner irqs are already disabled here.  Simply
-	 * removing raw_local_irq_save above (and the matching
-	 * raw_local_irq_restore) was not accepted.  See
-	 * http://thread.gmane.org/gmane.linux.ports.arm.kernel/41174
-	 * So for now (2008-11-20) just warn once if irqs were not disabled ...
-	 */
-	WARN_ON_ONCE(!raw_irqs_disabled_flags(flags));
-
 	/* The alarm IRQ uses absolute time (now+delta), not the relative
 	 * time (delta) in our calling convention.  Like all clockevents
 	 * using such "match" hardware, we have a race to defend against.
@@ -169,7 +156,6 @@ clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev)
 	alm += delta;
 	at91_sys_write(AT91_ST_RTAR, alm);
 
-	raw_local_irq_restore(flags);
 	return status;
 }
 
diff --git a/arch/arm/mach-at91/at91sam926x_time.c b/arch/arm/mach-at91/at91sam926x_time.c
index 4bd56ae..c26cd6e 100644
--- a/arch/arm/mach-at91/at91sam926x_time.c
+++ b/arch/arm/mach-at91/at91sam926x_time.c
@@ -62,16 +62,12 @@ static struct clocksource pit_clk = {
 static void
 pit_clkevt_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 {
-	unsigned long	flags;
-
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
-		/* update clocksource counter, then enable the IRQ */
-		raw_local_irq_save(flags);
+		/* update clocksource counter */
 		pit_cnt += pit_cycle * PIT_PICNT(at91_sys_read(AT91_PIT_PIVR));
 		at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN
 				| AT91_PIT_PITIEN);
-		raw_local_irq_restore(flags);
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
 		BUG();
diff --git a/arch/arm/mach-nomadik/timer.c b/arch/arm/mach-nomadik/timer.c
index d1738e7..e361be6 100644
--- a/arch/arm/mach-nomadik/timer.c
+++ b/arch/arm/mach-nomadik/timer.c
@@ -54,24 +54,17 @@ static struct clocksource nmdk_clksrc = {
 static void nmdk_clkevt_mode(enum clock_event_mode mode,
 			     struct clock_event_device *dev)
 {
-	unsigned long flags;
-
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
-		/* enable interrupts -- and count current value? */
-		raw_local_irq_save(flags);
+		/* count current value? */
 		writel(readl(mtu_base + MTU_IMSC) | 1, mtu_base + MTU_IMSC);
-		raw_local_irq_restore(flags);
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
 		BUG(); /* Not supported, yet */
 		/* FALLTHROUGH */
 	case CLOCK_EVT_MODE_SHUTDOWN:
 	case CLOCK_EVT_MODE_UNUSED:
-		/* disable irq */
-		raw_local_irq_save(flags);
 		writel(readl(mtu_base + MTU_IMSC) & ~1, mtu_base + MTU_IMSC);
-		raw_local_irq_restore(flags);
 		break;
 	case CLOCK_EVT_MODE_RESUME:
 		break;
diff --git a/arch/arm/mach-pxa/time.c b/arch/arm/mach-pxa/time.c
index 750c448..293e40a 100644
--- a/arch/arm/mach-pxa/time.c
+++ b/arch/arm/mach-pxa/time.c
@@ -76,14 +76,12 @@ pxa_ost0_interrupt(int irq, void *dev_id)
 static int
 pxa_osmr0_set_next_event(unsigned long delta, struct clock_event_device *dev)
 {
-	unsigned long flags, next, oscr;
+	unsigned long next, oscr;
 
-	raw_local_irq_save(flags);
 	OIER |= OIER_E0;
 	next = OSCR + delta;
 	OSMR0 = next;
 	oscr = OSCR;
-	raw_local_irq_restore(flags);
 
 	return (signed)(next - oscr) <= MIN_OSCR_DELTA ? -ETIME : 0;
 }
@@ -91,23 +89,17 @@ pxa_osmr0_set_next_event(unsigned long delta, struct clock_event_device *dev)
 static void
 pxa_osmr0_set_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 {
-	unsigned long irqflags;
-
 	switch (mode) {
 	case CLOCK_EVT_MODE_ONESHOT:
-		raw_local_irq_save(irqflags);
 		OIER &= ~OIER_E0;
 		OSSR = OSSR_M0;
-		raw_local_irq_restore(irqflags);
 		break;
 
 	case CLOCK_EVT_MODE_UNUSED:
 	case CLOCK_EVT_MODE_SHUTDOWN:
 		/* initializing, released, or preparing for suspend */
-		raw_local_irq_save(irqflags);
 		OIER &= ~OIER_E0;
 		OSSR = OSSR_M0;
-		raw_local_irq_restore(irqflags);
 		break;
 
 	case CLOCK_EVT_MODE_RESUME:
diff --git a/arch/arm/mach-sa1100/time.c b/arch/arm/mach-sa1100/time.c
index b9cbb56..74b6e0e 100644
--- a/arch/arm/mach-sa1100/time.c
+++ b/arch/arm/mach-sa1100/time.c
@@ -35,14 +35,12 @@ static irqreturn_t sa1100_ost0_interrupt(int irq, void *dev_id)
 static int
 sa1100_osmr0_set_next_event(unsigned long delta, struct clock_event_device *c)
 {
-	unsigned long flags, next, oscr;
+	unsigned long next, oscr;
 
-	raw_local_irq_save(flags);
 	OIER |= OIER_E0;
 	next = OSCR + delta;
 	OSMR0 = next;
 	oscr = OSCR;
-	raw_local_irq_restore(flags);
 
 	return (signed)(next - oscr) <= MIN_OSCR_DELTA ? -ETIME : 0;
 }
@@ -50,16 +48,12 @@ sa1100_osmr0_set_next_event(unsigned long delta, struct clock_event_device *c)
 static void
 sa1100_osmr0_set_mode(enum clock_event_mode mode, struct clock_event_device *c)
 {
-	unsigned long flags;
-
 	switch (mode) {
 	case CLOCK_EVT_MODE_ONESHOT:
 	case CLOCK_EVT_MODE_UNUSED:
 	case CLOCK_EVT_MODE_SHUTDOWN:
-		raw_local_irq_save(flags);
 		OIER &= ~OIER_E0;
 		OSSR = OSSR_M0;
-		raw_local_irq_restore(flags);
 		break;
 
 	case CLOCK_EVT_MODE_RESUME:
-- 
1.6.5.2