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-rw-r--r--arch/arm/plat-samsung/s5p-time.c405
1 files changed, 405 insertions, 0 deletions
diff --git a/arch/arm/plat-samsung/s5p-time.c b/arch/arm/plat-samsung/s5p-time.c
new file mode 100644
index 0000000..028b6e8
--- /dev/null
+++ b/arch/arm/plat-samsung/s5p-time.c
@@ -0,0 +1,405 @@
+/*
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com/
+ *
+ * S5P - Common hr-timer support
+ *
+ * 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/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 <asm/mach/time.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+#include <asm/sched_clock.h>
+
+#include <mach/map.h>
+#include <plat/devs.h>
+#include <plat/regs-timer.h>
+#include <plat/s5p-time.h>
+
+static struct clk *tin_event;
+static struct clk *tin_source;
+static struct clk *tdiv_event;
+static struct clk *tdiv_source;
+static struct clk *timerclk;
+static struct s5p_timer_source timer_source;
+static unsigned long clock_count_per_tick;
+static void s5p_timer_resume(void);
+
+static void s5p_time_stop(enum s5p_timer_mode mode)
+{
+ unsigned long tcon;
+
+ tcon = __raw_readl(S3C2410_TCON);
+
+ switch (mode) {
+ case S5P_PWM0:
+ tcon &= ~S3C2410_TCON_T0START;
+ break;
+
+ case S5P_PWM1:
+ tcon &= ~S3C2410_TCON_T1START;
+ break;
+
+ case S5P_PWM2:
+ tcon &= ~S3C2410_TCON_T2START;
+ break;
+
+ case S5P_PWM3:
+ tcon &= ~S3C2410_TCON_T3START;
+ break;
+
+ case S5P_PWM4:
+ tcon &= ~S3C2410_TCON_T4START;
+ break;
+
+ default:
+ printk(KERN_ERR "Invalid Timer %d\n", mode);
+ break;
+ }
+ __raw_writel(tcon, S3C2410_TCON);
+}
+
+static void s5p_time_setup(enum s5p_timer_mode mode, unsigned long tcnt)
+{
+ unsigned long tcon;
+
+ tcon = __raw_readl(S3C2410_TCON);
+
+ tcnt--;
+
+ switch (mode) {
+ case S5P_PWM0:
+ tcon &= ~(0x0f << 0);
+ tcon |= S3C2410_TCON_T0MANUALUPD;
+ break;
+
+ case S5P_PWM1:
+ tcon &= ~(0x0f << 8);
+ tcon |= S3C2410_TCON_T1MANUALUPD;
+ break;
+
+ case S5P_PWM2:
+ tcon &= ~(0x0f << 12);
+ tcon |= S3C2410_TCON_T2MANUALUPD;
+ break;
+
+ case S5P_PWM3:
+ tcon &= ~(0x0f << 16);
+ tcon |= S3C2410_TCON_T3MANUALUPD;
+ break;
+
+ case S5P_PWM4:
+ tcon &= ~(0x07 << 20);
+ tcon |= S3C2410_TCON_T4MANUALUPD;
+ break;
+
+ default:
+ printk(KERN_ERR "Invalid Timer %d\n", mode);
+ break;
+ }
+
+ __raw_writel(tcnt, S3C2410_TCNTB(mode));
+ __raw_writel(tcnt, S3C2410_TCMPB(mode));
+ __raw_writel(tcon, S3C2410_TCON);
+}
+
+static void s5p_time_start(enum s5p_timer_mode mode, bool periodic)
+{
+ unsigned long tcon;
+
+ tcon = __raw_readl(S3C2410_TCON);
+
+ switch (mode) {
+ case S5P_PWM0:
+ tcon |= S3C2410_TCON_T0START;
+ tcon &= ~S3C2410_TCON_T0MANUALUPD;
+
+ if (periodic)
+ tcon |= S3C2410_TCON_T0RELOAD;
+ else
+ tcon &= ~S3C2410_TCON_T0RELOAD;
+ break;
+
+ case S5P_PWM1:
+ tcon |= S3C2410_TCON_T1START;
+ tcon &= ~S3C2410_TCON_T1MANUALUPD;
+
+ if (periodic)
+ tcon |= S3C2410_TCON_T1RELOAD;
+ else
+ tcon &= ~S3C2410_TCON_T1RELOAD;
+ break;
+
+ case S5P_PWM2:
+ tcon |= S3C2410_TCON_T2START;
+ tcon &= ~S3C2410_TCON_T2MANUALUPD;
+
+ if (periodic)
+ tcon |= S3C2410_TCON_T2RELOAD;
+ else
+ tcon &= ~S3C2410_TCON_T2RELOAD;
+ break;
+
+ case S5P_PWM3:
+ tcon |= S3C2410_TCON_T3START;
+ tcon &= ~S3C2410_TCON_T3MANUALUPD;
+
+ if (periodic)
+ tcon |= S3C2410_TCON_T3RELOAD;
+ else
+ tcon &= ~S3C2410_TCON_T3RELOAD;
+ break;
+
+ case S5P_PWM4:
+ tcon |= S3C2410_TCON_T4START;
+ tcon &= ~S3C2410_TCON_T4MANUALUPD;
+
+ if (periodic)
+ tcon |= S3C2410_TCON_T4RELOAD;
+ else
+ tcon &= ~S3C2410_TCON_T4RELOAD;
+ break;
+
+ default:
+ printk(KERN_ERR "Invalid Timer %d\n", mode);
+ break;
+ }
+ __raw_writel(tcon, S3C2410_TCON);
+}
+
+static int s5p_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ s5p_time_setup(timer_source.event_id, cycles);
+ s5p_time_start(timer_source.event_id, NON_PERIODIC);
+
+ return 0;
+}
+
+static void s5p_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ s5p_time_stop(timer_source.event_id);
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ s5p_time_setup(timer_source.event_id, clock_count_per_tick);
+ s5p_time_start(timer_source.event_id, PERIODIC);
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ break;
+
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ break;
+
+ case CLOCK_EVT_MODE_RESUME:
+ s5p_timer_resume();
+ break;
+ }
+}
+
+static void s5p_timer_resume(void)
+{
+ /* event timer restart */
+ s5p_time_setup(timer_source.event_id, clock_count_per_tick);
+ s5p_time_start(timer_source.event_id, PERIODIC);
+
+ /* source timer restart */
+ s5p_time_setup(timer_source.source_id, TCNT_MAX);
+ s5p_time_start(timer_source.source_id, PERIODIC);
+}
+
+void __init s5p_set_timer_source(enum s5p_timer_mode event,
+ enum s5p_timer_mode source)
+{
+ s3c_device_timer[event].dev.bus = &platform_bus_type;
+ s3c_device_timer[source].dev.bus = &platform_bus_type;
+
+ timer_source.event_id = event;
+ timer_source.source_id = source;
+}
+
+static struct clock_event_device time_event_device = {
+ .name = "s5p_event_timer",
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 200,
+ .set_next_event = s5p_set_next_event,
+ .set_mode = s5p_set_mode,
+};
+
+static irqreturn_t s5p_clock_event_isr(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction s5p_clock_event_irq = {
+ .name = "s5p_time_irq",
+ .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+ .handler = s5p_clock_event_isr,
+ .dev_id = &time_event_device,
+};
+
+static void __init s5p_clockevent_init(void)
+{
+ unsigned long pclk;
+ unsigned long clock_rate;
+ unsigned int irq_number;
+ struct clk *tscaler;
+
+ pclk = clk_get_rate(timerclk);
+
+ tscaler = clk_get_parent(tdiv_event);
+
+ clk_set_rate(tscaler, pclk / 2);
+ clk_set_rate(tdiv_event, pclk / 2);
+ clk_set_parent(tin_event, tdiv_event);
+
+ clock_rate = clk_get_rate(tin_event);
+ clock_count_per_tick = clock_rate / HZ;
+
+ clockevents_calc_mult_shift(&time_event_device,
+ clock_rate, S5PTIMER_MIN_RANGE);
+ time_event_device.max_delta_ns =
+ clockevent_delta2ns(-1, &time_event_device);
+ time_event_device.min_delta_ns =
+ clockevent_delta2ns(1, &time_event_device);
+
+ time_event_device.cpumask = cpumask_of(0);
+ clockevents_register_device(&time_event_device);
+
+ irq_number = timer_source.event_id + IRQ_TIMER0;
+ setup_irq(irq_number, &s5p_clock_event_irq);
+}
+
+static void __iomem *s5p_timer_reg(void)
+{
+ unsigned long offset = 0;
+
+ switch (timer_source.source_id) {
+ case S5P_PWM0:
+ case S5P_PWM1:
+ case S5P_PWM2:
+ case S5P_PWM3:
+ offset = (timer_source.source_id * 0x0c) + 0x14;
+ break;
+
+ case S5P_PWM4:
+ offset = 0x40;
+ break;
+
+ default:
+ printk(KERN_ERR "Invalid Timer %d\n", timer_source.source_id);
+ return NULL;
+ }
+
+ return S3C_TIMERREG(offset);
+}
+
+/*
+ * Override the global weak sched_clock symbol with this
+ * local implementation which uses the clocksource to get some
+ * better resolution when scheduling the kernel. We accept that
+ * this wraps around for now, since it is just a relative time
+ * stamp. (Inspired by U300 implementation.)
+ */
+static u32 notrace s5p_read_sched_clock(void)
+{
+ void __iomem *reg = s5p_timer_reg();
+
+ if (!reg)
+ return 0;
+
+ return ~__raw_readl(reg);
+}
+
+static void __init s5p_clocksource_init(void)
+{
+ unsigned long pclk;
+ unsigned long clock_rate;
+
+ pclk = clk_get_rate(timerclk);
+
+ clk_set_rate(tdiv_source, pclk / 2);
+ clk_set_parent(tin_source, tdiv_source);
+
+ clock_rate = clk_get_rate(tin_source);
+
+ s5p_time_setup(timer_source.source_id, TCNT_MAX);
+ s5p_time_start(timer_source.source_id, PERIODIC);
+
+ setup_sched_clock(s5p_read_sched_clock, 32, clock_rate);
+
+ if (clocksource_mmio_init(s5p_timer_reg(), "s5p_clocksource_timer",
+ clock_rate, 250, 32, clocksource_mmio_readl_down))
+ panic("s5p_clocksource_timer: can't register clocksource\n");
+}
+
+static void __init s5p_timer_resources(void)
+{
+
+ unsigned long event_id = timer_source.event_id;
+ unsigned long source_id = timer_source.source_id;
+ char devname[15];
+
+ timerclk = clk_get(NULL, "timers");
+ if (IS_ERR(timerclk))
+ panic("failed to get timers clock for timer");
+
+ clk_enable(timerclk);
+
+ sprintf(devname, "s3c24xx-pwm.%lu", event_id);
+ s3c_device_timer[event_id].id = event_id;
+ s3c_device_timer[event_id].dev.init_name = devname;
+
+ tin_event = clk_get(&s3c_device_timer[event_id].dev, "pwm-tin");
+ if (IS_ERR(tin_event))
+ panic("failed to get pwm-tin clock for event timer");
+
+ tdiv_event = clk_get(&s3c_device_timer[event_id].dev, "pwm-tdiv");
+ if (IS_ERR(tdiv_event))
+ panic("failed to get pwm-tdiv clock for event timer");
+
+ clk_enable(tin_event);
+
+ sprintf(devname, "s3c24xx-pwm.%lu", source_id);
+ s3c_device_timer[source_id].id = source_id;
+ s3c_device_timer[source_id].dev.init_name = devname;
+
+ tin_source = clk_get(&s3c_device_timer[source_id].dev, "pwm-tin");
+ if (IS_ERR(tin_source))
+ panic("failed to get pwm-tin clock for source timer");
+
+ tdiv_source = clk_get(&s3c_device_timer[source_id].dev, "pwm-tdiv");
+ if (IS_ERR(tdiv_source))
+ panic("failed to get pwm-tdiv clock for source timer");
+
+ clk_enable(tin_source);
+}
+
+static void __init s5p_timer_init(void)
+{
+ s5p_timer_resources();
+ s5p_clockevent_init();
+ s5p_clocksource_init();
+}
+
+struct sys_timer s5p_timer = {
+ .init = s5p_timer_init,
+};