[PATCH v7 03/14] ARM: smp_twd: add support for remapped PPI interrupts
From: Marc Zyngier <hidden>
Date: 2011-06-13 11:21:48
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
When CONFIG_ARM_GIC_VPPI is enabled, let smp_twd request interrupts the normal way (ie using request_irq()). This involves letting PPIs go via the same code path as SPIs and having normal interrupt handler for the local timer code. The previous ad-hoc code is still supported when CONFIG_ARM_GIC_VPPI is not defined. Signed-off-by: Marc Zyngier <redacted> Reviewed-by: Will Deacon <redacted> --- arch/arm/kernel/smp_twd.c | 28 +++++++++++++++++++++++++++- 1 files changed, 27 insertions(+), 1 deletions(-)
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index 60636f4..773336e 100644
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c@@ -15,16 +15,18 @@ #include <linux/smp.h> #include <linux/jiffies.h> #include <linux/clockchips.h> -#include <linux/irq.h> +#include <linux/interrupt.h> #include <linux/io.h> #include <asm/smp_twd.h> +#include <asm/localtimer.h> #include <asm/hardware/gic.h> /* set up by the platform code */ void __iomem *twd_base; static unsigned long twd_timer_rate; +static DEFINE_PER_CPU(bool, irq_reqd); static void twd_set_mode(enum clock_event_mode mode, struct clock_event_device *clk)
@@ -43,6 +45,10 @@ static void twd_set_mode(enum clock_event_mode mode, ctrl = TWD_TIMER_CONTROL_IT_ENABLE | TWD_TIMER_CONTROL_ONESHOT; break; case CLOCK_EVT_MODE_UNUSED: +#ifdef CONFIG_ARM_GIC_VPPI + disable_irq(clk->irq); + /* fall through */ +#endif case CLOCK_EVT_MODE_SHUTDOWN: default: ctrl = 0;
@@ -124,6 +130,9 @@ static void __cpuinit twd_calibrate_rate(void) */ void __cpuinit twd_timer_setup(struct clock_event_device *clk) { + int err; + bool *reqd; + twd_calibrate_rate(); clk->name = "local_timer";
@@ -137,8 +146,25 @@ void __cpuinit twd_timer_setup(struct clock_event_device *clk) clk->max_delta_ns = clockevent_delta2ns(0xffffffff, clk); clk->min_delta_ns = clockevent_delta2ns(0xf, clk); +#ifdef CONFIG_ARM_GIC_VPPI + reqd = &__get_cpu_var(irq_reqd); + if (!*reqd) { + err = request_irq(clk->irq, percpu_timer_handler, + IRQF_PERCPU | IRQF_NOBALANCING | IRQF_TIMER, + clk->name, clk); + if (err) { + pr_err("%s: can't register interrupt %d on cpu %d (%d)\n", + clk->name, clk->irq, smp_processor_id(), err); + return; + } + + *reqd = true; + } else + enable_irq(clk->irq); +#else /* Make sure our local interrupt controller has this enabled */ gic_enable_ppi(clk->irq); +#endif clockevents_register_device(clk); }
--
1.7.0.4