aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/kernel
diff options
context:
space:
mode:
authorMarc Gonzalez <marc_gonzalez@sigmadesigns.com>2015-10-09 10:20:47 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2015-10-09 16:22:53 +0100
commit194444c52edd857210b3895e83ce45c64b58e251 (patch)
tree65e0cc031ef48d29ab39561728c75df51ef1959f /arch/arm/kernel
parentff5138f3af4ed61ed42e00d7d771a0502460488f (diff)
downloadlinux-linaro-stable-194444c52edd857210b3895e83ce45c64b58e251.tar.gz
ARM: 8441/2: twd: Don't set CLOCK_EVT_FEAT_C3STOP unconditionally
In 5388a6b266 ("ARM: SMP: Always enable clock event broadcast support") Russell noted that "the TWD local timers are unable to wake up the CPU when it is placed into a low power mode". However, some platforms do not stop the TWD block in low-power mode, and can thus use the TWD timer in one-shot mode, without setting up a broadcast device. Make the driver check for the "always-on" boolean property, and set the CLOCK_EVT_FEAT_C3STOP flag accordingly. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Gonzalez <marc_gonzalez@sigmadesigns.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel')
-rw-r--r--arch/arm/kernel/smp_twd.c5
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index 662ed88bc1f9..4c1aa61149bb 100644
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -33,6 +33,7 @@ static unsigned long twd_timer_rate;
static DEFINE_PER_CPU(bool, percpu_setup_called);
static struct clock_event_device __percpu *twd_evt;
+static int feat_c3stop;
static int twd_ppi;
static int twd_shutdown(struct clock_event_device *clk)
@@ -294,7 +295,7 @@ static void twd_timer_setup(void)
clk->name = "local_timer";
clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
- CLOCK_EVT_FEAT_C3STOP;
+ feat_c3stop;
clk->rating = 350;
clk->set_state_shutdown = twd_shutdown;
clk->set_state_periodic = twd_set_periodic;
@@ -349,6 +350,8 @@ static int __init twd_local_timer_common_register(struct device_node *np)
goto out_irq;
twd_get_clock(np);
+ if (!of_property_read_bool(np, "always-on"))
+ feat_c3stop = CLOCK_EVT_FEAT_C3STOP;
/*
* Immediately configure the timer on the boot CPU, unless we need