--- /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.
+ *
+ * Based on kernel-v3.0/arch/arm/mach-exynos4/time.c
+*/
+
+#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(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 = 250,
+ .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(tin2);
+
+ 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;
+ char devname[15];
+
+ tmpdev.dev.bus = &platform_bus_type;
+
+ timerclk = clk_get(NULL, "sclk_pwm");
+ if (IS_ERR(timerclk))
+ panic("failed to get timers clock for system timer");
+
+ clk_enable(timerclk);
+
+ tmpdev.id = 2;
+ sprintf(devname, "s3c24xx-pwm.%d", tmpdev.id);
+ tmpdev.dev.init_name = devname;
+
+ 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;
+ sprintf(devname, "s3c24xx-pwm.%d", tmpdev.id);
+ tmpdev.dev.init_name = devname;
+
+ 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 tizen_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 tizen_timer = {
+ .init = tizen_timer_init,
+};
projects / sdk / emulator / emulator-kernel.git / commitdiff