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-rw-r--r--arch/arm/mach-omap2/timer.c342
1 files changed, 342 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
new file mode 100644
index 0000000..e964072
--- /dev/null
+++ b/arch/arm/mach-omap2/timer.c
@@ -0,0 +1,342 @@
+/*
+ * linux/arch/arm/mach-omap2/timer.c
+ *
+ * OMAP2 GP timer support.
+ *
+ * Copyright (C) 2009 Nokia Corporation
+ *
+ * Update to use new clocksource/clockevent layers
+ * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ *
+ * Original driver:
+ * Copyright (C) 2005 Nokia Corporation
+ * Author: Paul Mundt <paul.mundt@nokia.com>
+ * Juha Yrjölä <juha.yrjola@nokia.com>
+ * OMAP Dual-mode timer framework support by Timo Teras
+ *
+ * Some parts based off of TI's 24xx code:
+ *
+ * Copyright (C) 2004-2009 Texas Instruments, Inc.
+ *
+ * Roughly modelled after the OMAP1 MPU timer code.
+ * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+
+#include <asm/mach/time.h>
+#include <plat/dmtimer.h>
+#include <asm/localtimer.h>
+#include <asm/sched_clock.h>
+#include <plat/common.h>
+#include <plat/omap_hwmod.h>
+
+/* Parent clocks, eventually these will come from the clock framework */
+
+#define OMAP2_MPU_SOURCE "sys_ck"
+#define OMAP3_MPU_SOURCE OMAP2_MPU_SOURCE
+#define OMAP4_MPU_SOURCE "sys_clkin_ck"
+#define OMAP2_32K_SOURCE "func_32k_ck"
+#define OMAP3_32K_SOURCE "omap_32k_fck"
+#define OMAP4_32K_SOURCE "sys_32k_ck"
+
+#ifdef CONFIG_OMAP_32K_TIMER
+#define OMAP2_CLKEV_SOURCE OMAP2_32K_SOURCE
+#define OMAP3_CLKEV_SOURCE OMAP3_32K_SOURCE
+#define OMAP4_CLKEV_SOURCE OMAP4_32K_SOURCE
+#define OMAP3_SECURE_TIMER 12
+#else
+#define OMAP2_CLKEV_SOURCE OMAP2_MPU_SOURCE
+#define OMAP3_CLKEV_SOURCE OMAP3_MPU_SOURCE
+#define OMAP4_CLKEV_SOURCE OMAP4_MPU_SOURCE
+#define OMAP3_SECURE_TIMER 1
+#endif
+
+/* MAX_GPTIMER_ID: number of GPTIMERs on the chip */
+#define MAX_GPTIMER_ID 12
+
+u32 sys_timer_reserved;
+
+/* Clockevent code */
+
+static struct omap_dm_timer clkev;
+static struct clock_event_device clockevent_gpt;
+
+static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = &clockevent_gpt;
+
+ __omap_dm_timer_write_status(clkev.io_base, OMAP_TIMER_INT_OVERFLOW);
+
+ evt->event_handler(evt);
+ return IRQ_HANDLED;
+}
+
+static struct irqaction omap2_gp_timer_irq = {
+ .name = "gp timer",
+ .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+ .handler = omap2_gp_timer_interrupt,
+};
+
+static int omap2_gp_timer_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ __omap_dm_timer_load_start(clkev.io_base, OMAP_TIMER_CTRL_ST,
+ 0xffffffff - cycles, 1);
+
+ return 0;
+}
+
+static void omap2_gp_timer_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ u32 period;
+
+ __omap_dm_timer_stop(clkev.io_base, 1, clkev.rate);
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ period = clkev.rate / HZ;
+ period -= 1;
+ /* Looks like we need to first set the load value separately */
+ __omap_dm_timer_write(clkev.io_base, OMAP_TIMER_LOAD_REG,
+ 0xffffffff - period, 1);
+ __omap_dm_timer_load_start(clkev.io_base,
+ OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
+ 0xffffffff - period, 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 clockevent_gpt = {
+ .name = "gp timer",
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .shift = 32,
+ .set_next_event = omap2_gp_timer_set_next_event,
+ .set_mode = omap2_gp_timer_set_mode,
+};
+
+static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
+ int gptimer_id,
+ const char *fck_source)
+{
+ char name[10]; /* 10 = sizeof("gptXX_Xck0") */
+ struct omap_hwmod *oh;
+ size_t size;
+ int res = 0;
+
+ sprintf(name, "timer%d", gptimer_id);
+ omap_hwmod_setup_one(name);
+ oh = omap_hwmod_lookup(name);
+ if (!oh)
+ return -ENODEV;
+
+ timer->irq = oh->mpu_irqs[0].irq;
+ timer->phys_base = oh->slaves[0]->addr->pa_start;
+ size = oh->slaves[0]->addr->pa_end - timer->phys_base;
+
+ /* Static mapping, never released */
+ timer->io_base = ioremap(timer->phys_base, size);
+ if (!timer->io_base)
+ return -ENXIO;
+
+ /* After the dmtimer is using hwmod these clocks won't be needed */
+ sprintf(name, "gpt%d_fck", gptimer_id);
+ timer->fclk = clk_get(NULL, name);
+ if (IS_ERR(timer->fclk))
+ return -ENODEV;
+
+ sprintf(name, "gpt%d_ick", gptimer_id);
+ timer->iclk = clk_get(NULL, name);
+ if (IS_ERR(timer->iclk)) {
+ clk_put(timer->fclk);
+ return -ENODEV;
+ }
+
+ omap_hwmod_enable(oh);
+
+ sys_timer_reserved |= (1 << (gptimer_id - 1));
+
+ if (gptimer_id != 12) {
+ struct clk *src;
+
+ src = clk_get(NULL, fck_source);
+ if (IS_ERR(src)) {
+ res = -EINVAL;
+ } else {
+ res = __omap_dm_timer_set_source(timer->fclk, src);
+ if (IS_ERR_VALUE(res))
+ pr_warning("%s: timer%i cannot set source\n",
+ __func__, gptimer_id);
+ clk_put(src);
+ }
+ }
+ __omap_dm_timer_reset(timer->io_base, 1, 1);
+ timer->posted = 1;
+
+ timer->rate = clk_get_rate(timer->fclk);
+
+ timer->reserved = 1;
+
+ return res;
+}
+
+static void __init omap2_gp_clockevent_init(int gptimer_id,
+ const char *fck_source)
+{
+ int res;
+
+ res = omap_dm_timer_init_one(&clkev, gptimer_id, fck_source);
+ BUG_ON(res);
+
+ omap2_gp_timer_irq.dev_id = (void *)&clkev;
+ setup_irq(clkev.irq, &omap2_gp_timer_irq);
+
+ __omap_dm_timer_int_enable(clkev.io_base, OMAP_TIMER_INT_OVERFLOW);
+
+ clockevent_gpt.mult = div_sc(clkev.rate, NSEC_PER_SEC,
+ clockevent_gpt.shift);
+ clockevent_gpt.max_delta_ns =
+ clockevent_delta2ns(0xffffffff, &clockevent_gpt);
+ clockevent_gpt.min_delta_ns =
+ clockevent_delta2ns(3, &clockevent_gpt);
+ /* Timer internal resynch latency. */
+
+ clockevent_gpt.cpumask = cpumask_of(0);
+ clockevents_register_device(&clockevent_gpt);
+
+ pr_info("OMAP clockevent source: GPTIMER%d at %lu Hz\n",
+ gptimer_id, clkev.rate);
+}
+
+/* Clocksource code */
+
+#ifdef CONFIG_OMAP_32K_TIMER
+/*
+ * When 32k-timer is enabled, don't use GPTimer for clocksource
+ * instead, just leave default clocksource which uses the 32k
+ * sync counter. See clocksource setup in plat-omap/counter_32k.c
+ */
+
+static void __init omap2_gp_clocksource_init(int unused, const char *dummy)
+{
+ omap_init_clocksource_32k();
+}
+
+#else
+
+static struct omap_dm_timer clksrc;
+
+/*
+ * clocksource
+ */
+static DEFINE_CLOCK_DATA(cd);
+static cycle_t clocksource_read_cycles(struct clocksource *cs)
+{
+ return (cycle_t)__omap_dm_timer_read_counter(clksrc.io_base, 1);
+}
+
+static struct clocksource clocksource_gpt = {
+ .name = "gp timer",
+ .rating = 300,
+ .read = clocksource_read_cycles,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void notrace dmtimer_update_sched_clock(void)
+{
+ u32 cyc;
+
+ cyc = __omap_dm_timer_read_counter(clksrc.io_base, 1);
+
+ update_sched_clock(&cd, cyc, (u32)~0);
+}
+
+unsigned long long notrace sched_clock(void)
+{
+ u32 cyc = 0;
+
+ if (clksrc.reserved)
+ cyc = __omap_dm_timer_read_counter(clksrc.io_base, 1);
+
+ return cyc_to_sched_clock(&cd, cyc, (u32)~0);
+}
+
+/* Setup free-running counter for clocksource */
+static void __init omap2_gp_clocksource_init(int gptimer_id,
+ const char *fck_source)
+{
+ int res;
+
+ res = omap_dm_timer_init_one(&clksrc, gptimer_id, fck_source);
+ BUG_ON(res);
+
+ pr_info("OMAP clocksource: GPTIMER%d at %lu Hz\n",
+ gptimer_id, clksrc.rate);
+
+ __omap_dm_timer_load_start(clksrc.io_base, OMAP_TIMER_CTRL_ST, 0, 1);
+ init_sched_clock(&cd, dmtimer_update_sched_clock, 32, clksrc.rate);
+
+ if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
+ pr_err("Could not register clocksource %s\n",
+ clocksource_gpt.name);
+}
+#endif
+
+#define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src, \
+ clksrc_nr, clksrc_src) \
+static void __init omap##name##_timer_init(void) \
+{ \
+ omap2_gp_clockevent_init((clkev_nr), clkev_src); \
+ omap2_gp_clocksource_init((clksrc_nr), clksrc_src); \
+}
+
+#define OMAP_SYS_TIMER(name) \
+struct sys_timer omap##name##_timer = { \
+ .init = omap##name##_timer_init, \
+};
+
+#ifdef CONFIG_ARCH_OMAP2
+OMAP_SYS_TIMER_INIT(2, 1, OMAP2_CLKEV_SOURCE, 2, OMAP2_MPU_SOURCE)
+OMAP_SYS_TIMER(2)
+#endif
+
+#ifdef CONFIG_ARCH_OMAP3
+OMAP_SYS_TIMER_INIT(3, 1, OMAP3_CLKEV_SOURCE, 2, OMAP3_MPU_SOURCE)
+OMAP_SYS_TIMER(3)
+OMAP_SYS_TIMER_INIT(3_secure, OMAP3_SECURE_TIMER, OMAP3_CLKEV_SOURCE,
+ 2, OMAP3_MPU_SOURCE)
+OMAP_SYS_TIMER(3_secure)
+#endif
+
+#ifdef CONFIG_ARCH_OMAP4
+static void __init omap4_timer_init(void)
+{
+#ifdef CONFIG_LOCAL_TIMERS
+ twd_base = ioremap(OMAP44XX_LOCAL_TWD_BASE, SZ_256);
+ BUG_ON(!twd_base);
+#endif
+ omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE);
+ omap2_gp_clocksource_init(2, OMAP4_MPU_SOURCE);
+}
+OMAP_SYS_TIMER(4)
+#endif
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