diff options
Diffstat (limited to 'drivers/clocksource/arm_generic.c')
| -rw-r--r-- | drivers/clocksource/arm_generic.c | 232 | 
1 files changed, 0 insertions, 232 deletions
diff --git a/drivers/clocksource/arm_generic.c b/drivers/clocksource/arm_generic.c deleted file mode 100644 index 8ae1a61523ff..000000000000 --- a/drivers/clocksource/arm_generic.c +++ /dev/null @@ -1,232 +0,0 @@ -/* - * Generic timers support - * - * Copyright (C) 2012 ARM Ltd. - * Author: Marc Zyngier <[email protected]> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program.  If not, see <http://www.gnu.org/licenses/>. - */ - -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/delay.h> -#include <linux/device.h> -#include <linux/smp.h> -#include <linux/cpu.h> -#include <linux/jiffies.h> -#include <linux/interrupt.h> -#include <linux/clockchips.h> -#include <linux/of_irq.h> -#include <linux/io.h> - -#include <clocksource/arm_generic.h> - -#include <asm/arm_generic.h> - -static u32 arch_timer_rate; -static u64 sched_clock_mult __read_mostly; -static DEFINE_PER_CPU(struct clock_event_device, arch_timer_evt); -static int arch_timer_ppi; - -static irqreturn_t arch_timer_handle_irq(int irq, void *dev_id) -{ -	struct clock_event_device *evt = dev_id; -	unsigned long ctrl; - -	ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL); -	if (ctrl & ARCH_TIMER_CTRL_ISTATUS) { -		ctrl |= ARCH_TIMER_CTRL_IMASK; -		arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl); -		evt->event_handler(evt); -		return IRQ_HANDLED; -	} - -	return IRQ_NONE; -} - -static void arch_timer_stop(void) -{ -	unsigned long ctrl; - -	ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL); -	ctrl &= ~ARCH_TIMER_CTRL_ENABLE; -	arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl); -} - -static void arch_timer_set_mode(enum clock_event_mode mode, -				struct clock_event_device *clk) -{ -	switch (mode) { -	case CLOCK_EVT_MODE_UNUSED: -	case CLOCK_EVT_MODE_SHUTDOWN: -		arch_timer_stop(); -		break; -	default: -		break; -	} -} - -static int arch_timer_set_next_event(unsigned long evt, -				     struct clock_event_device *unused) -{ -	unsigned long ctrl; - -	ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL); -	ctrl |= ARCH_TIMER_CTRL_ENABLE; -	ctrl &= ~ARCH_TIMER_CTRL_IMASK; - -	arch_timer_reg_write(ARCH_TIMER_REG_TVAL, evt); -	arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl); - -	return 0; -} - -static void __cpuinit arch_timer_setup(struct clock_event_device *clk) -{ -	/* Let's make sure the timer is off before doing anything else */ -	arch_timer_stop(); - -	clk->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP; -	clk->name = "arch_sys_timer"; -	clk->rating = 400; -	clk->set_mode = arch_timer_set_mode; -	clk->set_next_event = arch_timer_set_next_event; -	clk->irq = arch_timer_ppi; -	clk->cpumask = cpumask_of(smp_processor_id()); - -	clockevents_config_and_register(clk, arch_timer_rate, -					0xf, 0x7fffffff); - -	enable_percpu_irq(clk->irq, 0); - -	/* Ensure the virtual counter is visible to userspace for the vDSO. */ -	arch_counter_enable_user_access(); -} - -static void __init arch_timer_calibrate(void) -{ -	if (arch_timer_rate == 0) { -		arch_timer_reg_write(ARCH_TIMER_REG_CTRL, 0); -		arch_timer_rate = arch_timer_reg_read(ARCH_TIMER_REG_FREQ); - -		/* Check the timer frequency. */ -		if (arch_timer_rate == 0) -			panic("Architected timer frequency is set to zero.\n" -			      "You must set this in your .dts file\n"); -	} - -	/* Cache the sched_clock multiplier to save a divide in the hot path. */ - -	sched_clock_mult = DIV_ROUND_CLOSEST(NSEC_PER_SEC, arch_timer_rate); - -	pr_info("Architected local timer running at %u.%02uMHz.\n", -		 arch_timer_rate / 1000000, (arch_timer_rate / 10000) % 100); -} - -static cycle_t arch_counter_read(struct clocksource *cs) -{ -	return arch_counter_get_cntpct(); -} - -static struct clocksource clocksource_counter = { -	.name	= "arch_sys_counter", -	.rating	= 400, -	.read	= arch_counter_read, -	.mask	= CLOCKSOURCE_MASK(56), -	.flags	= (CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_VALID_FOR_HRES), -}; - -int read_current_timer(unsigned long *timer_value) -{ -	*timer_value = arch_counter_get_cntpct(); -	return 0; -} - -unsigned long long notrace sched_clock(void) -{ -	return arch_counter_get_cntvct() * sched_clock_mult; -} - -static int __cpuinit arch_timer_cpu_notify(struct notifier_block *self, -					   unsigned long action, void *hcpu) -{ -	int cpu = (long)hcpu; -	struct clock_event_device *clk = per_cpu_ptr(&arch_timer_evt, cpu); - -	switch(action) { -	case CPU_STARTING: -	case CPU_STARTING_FROZEN: -		arch_timer_setup(clk); -		break; - -	case CPU_DYING: -	case CPU_DYING_FROZEN: -		pr_debug("arch_timer_teardown disable IRQ%d cpu #%d\n", -			 clk->irq, cpu); -		disable_percpu_irq(clk->irq); -		arch_timer_set_mode(CLOCK_EVT_MODE_UNUSED, clk); -		break; -	} - -	return NOTIFY_OK; -} - -static struct notifier_block __cpuinitdata arch_timer_cpu_nb = { -	.notifier_call = arch_timer_cpu_notify, -}; - -static const struct of_device_id arch_timer_of_match[] __initconst = { -	{ .compatible = "arm,armv8-timer" }, -	{}, -}; - -int __init arm_generic_timer_init(void) -{ -	struct device_node *np; -	int err; -	u32 freq; - -	np = of_find_matching_node(NULL, arch_timer_of_match); -	if (!np) { -		pr_err("arch_timer: can't find DT node\n"); -		return -ENODEV; -	} - -	/* Try to determine the frequency from the device tree or CNTFRQ */ -	if (!of_property_read_u32(np, "clock-frequency", &freq)) -		arch_timer_rate = freq; -	arch_timer_calibrate(); - -	arch_timer_ppi = irq_of_parse_and_map(np, 0); -	pr_info("arch_timer: found %s irq %d\n", np->name, arch_timer_ppi); - -	err = request_percpu_irq(arch_timer_ppi, arch_timer_handle_irq, -				 np->name, &arch_timer_evt); -	if (err) { -		pr_err("arch_timer: can't register interrupt %d (%d)\n", -		       arch_timer_ppi, err); -		return err; -	} - -	clocksource_register_hz(&clocksource_counter, arch_timer_rate); - -	/* Calibrate the delay loop directly */ -	lpj_fine = DIV_ROUND_CLOSEST(arch_timer_rate, HZ); - -	/* Immediately configure the timer on the boot CPU */ -	arch_timer_setup(this_cpu_ptr(&arch_timer_evt)); - -	register_cpu_notifier(&arch_timer_cpu_nb); - -	return 0; -}  |