105 lines
2.4 KiB
C
105 lines
2.4 KiB
C
/*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*
|
|
* Copyright (C) 2013 Imagination Technologies Ltd.
|
|
*/
|
|
#include <linux/clockchips.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/percpu.h>
|
|
#include <linux/smp.h>
|
|
#include <linux/irq.h>
|
|
|
|
#include <asm/time.h>
|
|
#include <asm/gic.h>
|
|
#include <asm/mips-boards/maltaint.h>
|
|
|
|
DEFINE_PER_CPU(struct clock_event_device, gic_clockevent_device);
|
|
int gic_timer_irq_installed;
|
|
|
|
|
|
static int gic_next_event(unsigned long delta, struct clock_event_device *evt)
|
|
{
|
|
u64 cnt;
|
|
int res;
|
|
|
|
cnt = gic_read_count();
|
|
cnt += (u64)delta;
|
|
gic_write_cpu_compare(cnt, cpumask_first(evt->cpumask));
|
|
res = ((int)(gic_read_count() - cnt) >= 0) ? -ETIME : 0;
|
|
return res;
|
|
}
|
|
|
|
void gic_set_clock_mode(enum clock_event_mode mode,
|
|
struct clock_event_device *evt)
|
|
{
|
|
/* Nothing to do ... */
|
|
}
|
|
|
|
irqreturn_t gic_compare_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct clock_event_device *cd;
|
|
int cpu = smp_processor_id();
|
|
|
|
gic_write_compare(gic_read_compare());
|
|
cd = &per_cpu(gic_clockevent_device, cpu);
|
|
cd->event_handler(cd);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
struct irqaction gic_compare_irqaction = {
|
|
.handler = gic_compare_interrupt,
|
|
.flags = IRQF_PERCPU | IRQF_TIMER,
|
|
.name = "timer",
|
|
};
|
|
|
|
|
|
void gic_event_handler(struct clock_event_device *dev)
|
|
{
|
|
}
|
|
|
|
int gic_clockevent_init(void)
|
|
{
|
|
unsigned int cpu = smp_processor_id();
|
|
struct clock_event_device *cd;
|
|
unsigned int irq;
|
|
|
|
if (!cpu_has_counter || !gic_frequency)
|
|
return -ENXIO;
|
|
|
|
irq = MIPS_GIC_IRQ_BASE;
|
|
|
|
cd = &per_cpu(gic_clockevent_device, cpu);
|
|
|
|
cd->name = "MIPS GIC";
|
|
cd->features = CLOCK_EVT_FEAT_ONESHOT |
|
|
CLOCK_EVT_FEAT_C3STOP;
|
|
|
|
clockevent_set_clock(cd, gic_frequency);
|
|
|
|
/* Calculate the min / max delta */
|
|
cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd);
|
|
cd->min_delta_ns = clockevent_delta2ns(0x300, cd);
|
|
|
|
cd->rating = 300;
|
|
cd->irq = irq;
|
|
cd->cpumask = cpumask_of(cpu);
|
|
cd->set_next_event = gic_next_event;
|
|
cd->set_mode = gic_set_clock_mode;
|
|
cd->event_handler = gic_event_handler;
|
|
|
|
clockevents_register_device(cd);
|
|
|
|
GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_MAP), 0x80000002);
|
|
GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_SMASK), GIC_VPE_SMASK_CMP_MSK);
|
|
|
|
if (gic_timer_irq_installed)
|
|
return 0;
|
|
|
|
gic_timer_irq_installed = 1;
|
|
|
|
setup_irq(irq, &gic_compare_irqaction);
|
|
irq_set_handler(irq, handle_percpu_irq);
|
|
return 0;
|
|
}
|