+++ /dev/null
-/* linux/arch/arm/mach-exynos4/time.c
- *
- * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd.
- * http://www.samsung.com
- *
- * EXYNOS4 (and compatible) HRT support
- * PWM 2/4 is used for this feature
- *
- * 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/sched.h>
-#include <linux/interrupt.h>
-#include <linux/irq.h>
-#include <linux/err.h>
-#include <linux/clk.h>
-#include <linux/clockchips.h>
-#include <linux/platform_device.h>
-
-#include <asm/smp_twd.h>
-
-#include <mach/map.h>
-#include <plat/regs-timer.h>
-#include <asm/mach/time.h>
-
-static unsigned long clock_count_per_tick;
-
-static struct clk *tin2;
-static struct clk *tin4;
-static struct clk *tdiv2;
-static struct clk *tdiv4;
-static struct clk *timerclk;
-
-static void exynos4_pwm_stop(unsigned int pwm_id)
-{
- unsigned long tcon;
-
- tcon = __raw_readl(S3C2410_TCON);
-
- switch (pwm_id) {
- case 2:
- tcon &= ~S3C2410_TCON_T2START;
- break;
- case 4:
- tcon &= ~S3C2410_TCON_T4START;
- break;
- default:
- break;
- }
- __raw_writel(tcon, S3C2410_TCON);
-}
-
-static void exynos4_pwm_init(unsigned int pwm_id, unsigned long tcnt)
-{
- unsigned long tcon;
-
- tcon = __raw_readl(S3C2410_TCON);
-
- /* timers reload after counting zero, so reduce the count by 1 */
- tcnt--;
-
- /* ensure timer is stopped... */
- switch (pwm_id) {
- case 2:
- tcon &= ~(0xf<<12);
- tcon |= S3C2410_TCON_T2MANUALUPD;
-
- __raw_writel(tcnt, S3C2410_TCNTB(2));
- __raw_writel(tcnt, S3C2410_TCMPB(2));
- __raw_writel(tcon, S3C2410_TCON);
-
- break;
- case 4:
- tcon &= ~(7<<20);
- tcon |= S3C2410_TCON_T4MANUALUPD;
-
- __raw_writel(tcnt, S3C2410_TCNTB(4));
- __raw_writel(tcnt, S3C2410_TCMPB(4));
- __raw_writel(tcon, S3C2410_TCON);
-
- break;
- default:
- break;
- }
-}
-
-static inline void exynos4_pwm_start(unsigned int pwm_id, bool periodic)
-{
- unsigned long tcon;
-
- tcon = __raw_readl(S3C2410_TCON);
-
- switch (pwm_id) {
- case 2:
- tcon |= S3C2410_TCON_T2START;
- tcon &= ~S3C2410_TCON_T2MANUALUPD;
-
- if (periodic)
- tcon |= S3C2410_TCON_T2RELOAD;
- else
- tcon &= ~S3C2410_TCON_T2RELOAD;
- break;
- case 4:
- tcon |= S3C2410_TCON_T4START;
- tcon &= ~S3C2410_TCON_T4MANUALUPD;
-
- if (periodic)
- tcon |= S3C2410_TCON_T4RELOAD;
- else
- tcon &= ~S3C2410_TCON_T4RELOAD;
- break;
- default:
- break;
- }
- __raw_writel(tcon, S3C2410_TCON);
-}
-
-static int exynos4_pwm_set_next_event(unsigned long cycles,
- struct clock_event_device *evt)
-{
- exynos4_pwm_init(2, cycles);
- exynos4_pwm_start(2, 0);
- return 0;
-}
-
-static void exynos4_pwm_set_mode(enum clock_event_mode mode,
- struct clock_event_device *evt)
-{
- exynos4_pwm_stop(2);
-
- switch (mode) {
- case CLOCK_EVT_MODE_PERIODIC:
- exynos4_pwm_init(2, clock_count_per_tick);
- exynos4_pwm_start(2, 1);
- break;
- case CLOCK_EVT_MODE_ONESHOT:
- break;
- case CLOCK_EVT_MODE_UNUSED:
- case CLOCK_EVT_MODE_SHUTDOWN:
- case CLOCK_EVT_MODE_RESUME:
- break;
- }
-}
-
-static struct clock_event_device pwm_event_device = {
- .name = "pwm_timer2",
- .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
- .rating = 200,
- .shift = 32,
- .set_next_event = exynos4_pwm_set_next_event,
- .set_mode = exynos4_pwm_set_mode,
-};
-
-irqreturn_t exynos4_clock_event_isr(int irq, void *dev_id)
-{
- struct clock_event_device *evt = &pwm_event_device;
-
- evt->event_handler(evt);
-
- return IRQ_HANDLED;
-}
-
-static struct irqaction exynos4_clock_event_irq = {
- .name = "pwm_timer2_irq",
- .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
- .handler = exynos4_clock_event_isr,
-};
-
-static void __init exynos4_clockevent_init(void)
-{
- unsigned long pclk;
- unsigned long clock_rate;
- struct clk *tscaler;
-
- pclk = clk_get_rate(timerclk);
-
- /* configure clock tick */
-
- tscaler = clk_get_parent(tdiv2);
-
- clk_set_rate(tscaler, pclk / 2);
- clk_set_rate(tdiv2, pclk / 2);
- clk_set_parent(tin2, tdiv2);
-
- clock_rate = clk_get_rate(tin2);
-
- clock_count_per_tick = clock_rate / HZ;
-
- pwm_event_device.mult =
- div_sc(clock_rate, NSEC_PER_SEC, pwm_event_device.shift);
- pwm_event_device.max_delta_ns =
- clockevent_delta2ns(-1, &pwm_event_device);
- pwm_event_device.min_delta_ns =
- clockevent_delta2ns(1, &pwm_event_device);
-
- pwm_event_device.cpumask = cpumask_of(0);
- clockevents_register_device(&pwm_event_device);
-
- setup_irq(IRQ_TIMER2, &exynos4_clock_event_irq);
-}
-
-static cycle_t exynos4_pwm4_read(struct clocksource *cs)
-{
- return (cycle_t) ~__raw_readl(S3C_TIMERREG(0x40));
-}
-
-#ifdef CONFIG_PM
-static void exynos4_pwm4_resume(struct clocksource *cs)
-{
- unsigned long pclk;
-
- pclk = clk_get_rate(timerclk);
-
- clk_set_rate(tdiv4, pclk / 2);
- clk_set_parent(tin4, tdiv4);
-
- exynos4_pwm_init(4, ~0);
- exynos4_pwm_start(4, 1);
-}
-#endif
-
-struct clocksource pwm_clocksource = {
- .name = "pwm_timer4",
- .rating = 250,
- .read = exynos4_pwm4_read,
- .mask = CLOCKSOURCE_MASK(32),
- .flags = CLOCK_SOURCE_IS_CONTINUOUS ,
-#ifdef CONFIG_PM
- .resume = exynos4_pwm4_resume,
-#endif
-};
-
-static void __init exynos4_clocksource_init(void)
-{
- unsigned long pclk;
- unsigned long clock_rate;
-
- pclk = clk_get_rate(timerclk);
-
- clk_set_rate(tdiv4, pclk / 2);
- clk_set_parent(tin4, tdiv4);
-
- clock_rate = clk_get_rate(tin4);
-
- exynos4_pwm_init(4, ~0);
- exynos4_pwm_start(4, 1);
-
- if (clocksource_register_hz(&pwm_clocksource, clock_rate))
- panic("%s: can't register clocksource\n", pwm_clocksource.name);
-}
-
-static void __init exynos4_timer_resources(void)
-{
- struct platform_device tmpdev;
-
- tmpdev.dev.bus = &platform_bus_type;
-
- timerclk = clk_get(NULL, "timers");
- if (IS_ERR(timerclk))
- panic("failed to get timers clock for system timer");
-
- clk_enable(timerclk);
-
- tmpdev.id = 2;
- tin2 = clk_get(&tmpdev.dev, "pwm-tin");
- if (IS_ERR(tin2))
- panic("failed to get pwm-tin2 clock for system timer");
-
- tdiv2 = clk_get(&tmpdev.dev, "pwm-tdiv");
- if (IS_ERR(tdiv2))
- panic("failed to get pwm-tdiv2 clock for system timer");
- clk_enable(tin2);
-
- tmpdev.id = 4;
- tin4 = clk_get(&tmpdev.dev, "pwm-tin");
- if (IS_ERR(tin4))
- panic("failed to get pwm-tin4 clock for system timer");
-
- tdiv4 = clk_get(&tmpdev.dev, "pwm-tdiv");
- if (IS_ERR(tdiv4))
- panic("failed to get pwm-tdiv4 clock for system timer");
-
- clk_enable(tin4);
-}
-
-static void __init exynos4_timer_init(void)
-{
-#ifdef CONFIG_LOCAL_TIMERS
- twd_base = S5P_VA_TWD;
-#endif
-
- exynos4_timer_resources();
- exynos4_clockevent_init();
- exynos4_clocksource_init();
-}
-
-struct sys_timer exynos4_timer = {
- .init = exynos4_timer_init,
-};
projects / GitHub / exynos8895 / android_kernel_samsung_universal8895.git / commitdiff