cregit-Linux how code gets into the kernel

Release 4.9 arch/arm/mach-mmp/time.c

/*
 * linux/arch/arm/mach-mmp/time.c
 *
 *   Support for clocksource and clockevents
 *
 * Copyright (C) 2008 Marvell International Ltd.
 * All rights reserved.
 *
 *   2008-04-11: Jason Chagas <Jason.chagas@marvell.com>
 *   2008-10-08: Bin Yang <bin.yang@marvell.com>
 *
 * The timers module actually includes three timers, each timer with up to
 * three match comparators. Timer #0 is used here in free-running mode as
 * the clock source, and match comparator #1 used as clock event device.
 *
 * 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.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/clockchips.h>

#include <linux/io.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/sched_clock.h>
#include <asm/mach/time.h>

#include "addr-map.h"
#include "regs-timers.h"
#include "regs-apbc.h"
#include "irqs.h"
#include "cputype.h"
#include "clock.h"

#ifdef CONFIG_CPU_MMP2

#define MMP_CLOCK_FREQ		6500000
#else

#define MMP_CLOCK_FREQ		3250000
#endif


#define TIMERS_VIRT_BASE	TIMERS1_VIRT_BASE


#define MAX_DELTA		(0xfffffffe)

#define MIN_DELTA		(16)


static void __iomem *mmp_timer_base = TIMERS_VIRT_BASE;

/*
 * FIXME: the timer needs some delay to stablize the counter capture
 */

static inline uint32_t timer_read(void) { int delay = 100; __raw_writel(1, mmp_timer_base + TMR_CVWR(1)); while (delay--) cpu_relax(); return __raw_readl(mmp_timer_base + TMR_CVWR(1)); }

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lennert buytenheklennert buytenhek24.44%133.33%
haojian zhuanghaojian zhuang24.44%133.33%
Total45100.00%3100.00%


static u64 notrace mmp_read_sched_clock(void) { return timer_read(); }

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russell kingrussell king969.23%133.33%
marc zyngiermarc zyngier323.08%133.33%
stephen boydstephen boyd17.69%133.33%
Total13100.00%3100.00%


static irqreturn_t timer_interrupt(int irq, void *dev_id) { struct clock_event_device *c = dev_id; /* * Clear pending interrupt status. */ __raw_writel(0x01, mmp_timer_base + TMR_ICR(0)); /* * Disable timer 0. */ __raw_writel(0x02, mmp_timer_base + TMR_CER); c->event_handler(c); return IRQ_HANDLED; }

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eric miaoeric miao4584.91%133.33%
lennert buytenheklennert buytenhek611.32%133.33%
haojian zhuanghaojian zhuang23.77%133.33%
Total53100.00%3100.00%


static int timer_set_next_event(unsigned long delta, struct clock_event_device *dev) { unsigned long flags; local_irq_save(flags); /* * Disable timer 0. */ __raw_writel(0x02, mmp_timer_base + TMR_CER); /* * Clear and enable timer match 0 interrupt. */ __raw_writel(0x01, mmp_timer_base + TMR_ICR(0)); __raw_writel(0x01, mmp_timer_base + TMR_IER(0)); /* * Setup new clockevent timer value. */ __raw_writel(delta - 1, mmp_timer_base + TMR_TN_MM(0, 0)); /* * Enable timer 0. */ __raw_writel(0x03, mmp_timer_base + TMR_CER); local_irq_restore(flags); return 0; }

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lennert buytenheklennert buytenhek2324.47%133.33%
haojian zhuanghaojian zhuang55.32%133.33%
Total94100.00%3100.00%


static int timer_set_shutdown(struct clock_event_device *evt) { unsigned long flags; local_irq_save(flags); /* disable the matching interrupt */ __raw_writel(0x00, mmp_timer_base + TMR_IER(0)); local_irq_restore(flags); return 0; }

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viresh kumarviresh kumar614.63%133.33%
haojian zhuanghaojian zhuang12.44%133.33%
Total41100.00%3100.00%

static struct clock_event_device ckevt = { .name = "clockevent", .features = CLOCK_EVT_FEAT_ONESHOT, .rating = 200, .set_next_event = timer_set_next_event, .set_state_shutdown = timer_set_shutdown, .set_state_oneshot = timer_set_shutdown, };
static cycle_t clksrc_read(struct clocksource *cs) { return timer_read(); }

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eric miaoeric miao1173.33%150.00%
coly licoly li426.67%150.00%
Total15100.00%2100.00%

static struct clocksource cksrc = { .name = "clocksource", .rating = 200, .read = clksrc_read, .mask = CLOCKSOURCE_MASK(32), .flags = CLOCK_SOURCE_IS_CONTINUOUS, };
static void __init timer_config(void) { uint32_t ccr = __raw_readl(mmp_timer_base + TMR_CCR); __raw_writel(0x0, mmp_timer_base + TMR_CER); /* disable */ ccr &= (cpu_is_mmp2()) ? (TMR_CCR_CS_0(0) | TMR_CCR_CS_1(0)) : (TMR_CCR_CS_0(3) | TMR_CCR_CS_1(3)); __raw_writel(ccr, mmp_timer_base + TMR_CCR); /* set timer 0 to periodic mode, and timer 1 to free-running mode */ __raw_writel(0x2, mmp_timer_base + TMR_CMR); __raw_writel(0x1, mmp_timer_base + TMR_PLCR(0)); /* periodic */ __raw_writel(0x7, mmp_timer_base + TMR_ICR(0)); /* clear status */ __raw_writel(0x0, mmp_timer_base + TMR_IER(0)); __raw_writel(0x0, mmp_timer_base + TMR_PLCR(1)); /* free-running */ __raw_writel(0x7, mmp_timer_base + TMR_ICR(1)); /* clear status */ __raw_writel(0x0, mmp_timer_base + TMR_IER(1)); /* enable timer 1 counter */ __raw_writel(0x2, mmp_timer_base + TMR_CER); }

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eric miaoeric miao8752.73%120.00%
lennert buytenheklennert buytenhek5633.94%240.00%
haojian zhuanghaojian zhuang2213.33%240.00%
Total165100.00%5100.00%

static struct irqaction timer_irq = { .name = "timer", .flags = IRQF_TIMER | IRQF_IRQPOLL, .handler = timer_interrupt, .dev_id = &ckevt, };
void __init timer_init(int irq) { timer_config(); sched_clock_register(mmp_read_sched_clock, 32, MMP_CLOCK_FREQ); ckevt.cpumask = cpumask_of(0); setup_irq(irq, &timer_irq); clocksource_register_hz(&cksrc, MMP_CLOCK_FREQ); clockevents_config_and_register(&ckevt, MMP_CLOCK_FREQ, MIN_DELTA, MAX_DELTA); }

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eric miaoeric miao4272.41%114.29%
shawn guoshawn guo610.34%114.29%
russell kingrussell king58.62%228.57%
uwe kleine-koeniguwe kleine-koenig35.17%114.29%
marc zyngiermarc zyngier11.72%114.29%
stephen boydstephen boyd11.72%114.29%
Total58100.00%7100.00%

#ifdef CONFIG_OF static const struct of_device_id mmp_timer_dt_ids[] = { { .compatible = "mrvl,mmp-timer", }, {} };
void __init mmp_dt_init_timer(void) { struct device_node *np; int irq, ret; np = of_find_matching_node(NULL, mmp_timer_dt_ids); if (!np) { ret = -ENODEV; goto out; } irq = irq_of_parse_and_map(np, 0); if (!irq) { ret = -EINVAL; goto out; } mmp_timer_base = of_iomap(np, 0); if (!mmp_timer_base) { ret = -ENOMEM; goto out; } timer_init(irq); return; out: pr_err("Failed to get timer from device tree with error:%d\n", ret); }

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Total105100.00%1100.00%

#endif

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eric miaoeric miao46357.73%15.56%
haojian zhuanghaojian zhuang18222.69%211.11%
lennert buytenheklennert buytenhek8710.85%316.67%
uwe kleine-koeniguwe kleine-koenig192.37%211.11%
russell kingrussell king141.75%211.11%
viresh kumarviresh kumar131.62%15.56%
shawn guoshawn guo60.75%15.56%
arnd bergmannarnd bergmann60.75%15.56%
marc zyngiermarc zyngier40.50%15.56%
coly licoly li40.50%15.56%
stephen boydstephen boyd30.37%211.11%
lucas de marchilucas de marchi10.12%15.56%
Total802100.00%18100.00%