* Partial timer rewrite and additional dynamic tick timer support by
* Tony Lindgen <tony@atomide.com> and
* Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
+ * OMAP Dual-mode timer framework support by Timo Teras
*
* MPU timer code based on the older MPU timer code for OMAP
* Copyright (C) 2000 RidgeRun, Inc.
#include <linux/spinlock.h>
#include <linux/err.h>
#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
#include <asm/system.h>
#include <asm/hardware.h>
#include <asm/irq.h>
#include <asm/mach/irq.h>
#include <asm/mach/time.h>
+#include <asm/arch/dmtimer.h>
struct sys_timer omap_timer;
#define OMAP1_32K_TIMER_TVR 0x00
#define OMAP1_32K_TIMER_TCR 0x04
-/* 24xx specific defines */
-#define OMAP2_GP_TIMER_BASE 0x48028000
-#define CM_CLKSEL_WKUP 0x48008440
-#define GP_TIMER_TIDR 0x00
-#define GP_TIMER_TISR 0x18
-#define GP_TIMER_TIER 0x1c
-#define GP_TIMER_TCLR 0x24
-#define GP_TIMER_TCRR 0x28
-#define GP_TIMER_TLDR 0x2c
-#define GP_TIMER_TTGR 0x30
-#define GP_TIMER_TSICR 0x40
-
-#define OMAP_32K_TICKS_PER_HZ (32768 / HZ)
+#define OMAP_32K_TICKS_PER_SEC (32768)
/*
* TRM says 1 / HZ = ( TVR + 1) / 32768, so TRV = (32768 / HZ) - 1
* so with HZ = 128, TVR = 255.
*/
-#define OMAP_32K_TIMER_TICK_PERIOD ((32768 / HZ) - 1)
+#define OMAP_32K_TIMER_TICK_PERIOD ((OMAP_32K_TICKS_PER_SEC / HZ) - 1)
#define JIFFIES_TO_HW_TICKS(nr_jiffies, clock_rate) \
(((nr_jiffies) * (clock_rate)) / HZ)
+#if defined(CONFIG_ARCH_OMAP1)
+
static inline void omap_32k_timer_write(int val, int reg)
{
- if (cpu_class_is_omap1())
- omap_writew(val, OMAP1_32K_TIMER_BASE + reg);
-
- if (cpu_is_omap24xx())
- omap_writel(val, OMAP2_GP_TIMER_BASE + reg);
+ omap_writew(val, OMAP1_32K_TIMER_BASE + reg);
}
static inline unsigned long omap_32k_timer_read(int reg)
{
- if (cpu_class_is_omap1())
- return omap_readl(OMAP1_32K_TIMER_BASE + reg) & 0xffffff;
+ return omap_readl(OMAP1_32K_TIMER_BASE + reg) & 0xffffff;
+}
- if (cpu_is_omap24xx())
- return omap_readl(OMAP2_GP_TIMER_BASE + reg);
+static inline void omap_32k_timer_start(unsigned long load_val)
+{
+ if (!load_val)
+ load_val = 1;
+ omap_32k_timer_write(load_val, OMAP1_32K_TIMER_TVR);
+ omap_32k_timer_write(0x0f, OMAP1_32K_TIMER_CR);
}
-/*
- * The 32KHz synchronized timer is an additional timer on 16xx.
- * It is always running.
- */
-static inline unsigned long omap_32k_sync_timer_read(void)
+static inline void omap_32k_timer_stop(void)
{
- return omap_readl(TIMER_32K_SYNCHRONIZED);
+ omap_32k_timer_write(0x0, OMAP1_32K_TIMER_CR);
}
+#define omap_32k_timer_ack_irq()
+
+#elif defined(CONFIG_ARCH_OMAP2)
+
+static struct omap_dm_timer *gptimer;
+
static inline void omap_32k_timer_start(unsigned long load_val)
{
- if (cpu_class_is_omap1()) {
- omap_32k_timer_write(load_val, OMAP1_32K_TIMER_TVR);
- omap_32k_timer_write(0x0f, OMAP1_32K_TIMER_CR);
- }
-
- if (cpu_is_omap24xx()) {
- omap_32k_timer_write(0xffffffff - load_val, GP_TIMER_TCRR);
- omap_32k_timer_write((1 << 1), GP_TIMER_TIER);
- omap_32k_timer_write((1 << 1) | 1, GP_TIMER_TCLR);
- }
+ omap_dm_timer_set_load(gptimer, 1, 0xffffffff - load_val);
+ omap_dm_timer_set_int_enable(gptimer, OMAP_TIMER_INT_OVERFLOW);
+ omap_dm_timer_start(gptimer);
}
static inline void omap_32k_timer_stop(void)
{
- if (cpu_class_is_omap1())
- omap_32k_timer_write(0x0, OMAP1_32K_TIMER_CR);
+ omap_dm_timer_stop(gptimer);
+}
+
+static inline void omap_32k_timer_ack_irq(void)
+{
+ u32 status = omap_dm_timer_read_status(gptimer);
+ omap_dm_timer_write_status(gptimer, status);
+}
+
+#endif
- if (cpu_is_omap24xx())
- omap_32k_timer_write(0x0, GP_TIMER_TCLR);
+static void omap_32k_timer_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ switch (mode) {
+ case CLOCK_EVT_MODE_ONESHOT:
+ case CLOCK_EVT_MODE_PERIODIC:
+ omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD);
+ break;
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ omap_32k_timer_stop();
+ break;
+ }
+}
+
+static struct clock_event_device clockevent_32k_timer = {
+ .name = "32k-timer",
+ .features = CLOCK_EVT_FEAT_PERIODIC,
+ .shift = 32,
+ .set_mode = omap_32k_timer_set_mode,
+};
+
+/*
+ * The 32KHz synchronized timer is an additional timer on 16xx.
+ * It is always running.
+ */
+static inline unsigned long omap_32k_sync_timer_read(void)
+{
+ return omap_readl(TIMER_32K_SYNCHRONIZED);
}
/*
static unsigned long omap_32k_last_tick = 0;
-/*
- * Returns elapsed usecs since last 32k timer interrupt
- */
-static unsigned long omap_32k_timer_gettimeoffset(void)
-{
- unsigned long now = omap_32k_sync_timer_read();
- return omap_32k_ticks_to_usecs(now - omap_32k_last_tick);
-}
-
/*
* Returns current time from boot in nsecs. It's OK for this to wrap
* around for now, as it's just a relative time stamp.
return omap_32k_ticks_to_nsecs(omap_32k_sync_timer_read());
}
-/*
- * Timer interrupt for 32KHz timer. When dynamic tick is enabled, this
- * function is also called from other interrupts to remove latency
- * issues with dynamic tick. In the dynamic tick case, we need to lock
- * with irqsave.
- */
-static irqreturn_t omap_32k_timer_interrupt(int irq, void *dev_id,
- struct pt_regs *regs)
+static irqreturn_t omap_32k_timer_interrupt(int irq, void *dev_id)
{
- unsigned long flags;
- unsigned long now;
-
- write_seqlock_irqsave(&xtime_lock, flags);
-
- if (cpu_is_omap24xx()) {
- u32 status = omap_32k_timer_read(GP_TIMER_TISR);
- omap_32k_timer_write(status, GP_TIMER_TISR);
- }
-
- now = omap_32k_sync_timer_read();
-
- while ((signed long)(now - omap_32k_last_tick)
- >= OMAP_32K_TICKS_PER_HZ) {
- omap_32k_last_tick += OMAP_32K_TICKS_PER_HZ;
- timer_tick(regs);
- }
+ struct clock_event_device *evt = &clockevent_32k_timer;
+ omap_32k_timer_ack_irq();
- /* Restart timer so we don't drift off due to modulo or dynamic tick.
- * By default we program the next timer to be continuous to avoid
- * latencies during high system load. During dynamic tick operation the
- * continuous timer can be overridden from pm_idle to be longer.
- */
- omap_32k_timer_start(omap_32k_last_tick + OMAP_32K_TICKS_PER_HZ - now);
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ evt->event_handler(evt);
return IRQ_HANDLED;
}
-#ifdef CONFIG_NO_IDLE_HZ
-/*
- * Programs the next timer interrupt needed. Called when dynamic tick is
- * enabled, and to reprogram the ticks to skip from pm_idle. Note that
- * we can keep the timer continuous, and don't need to set it to run in
- * one-shot mode. This is because the timer will get reprogrammed again
- * after next interrupt.
- */
-void omap_32k_timer_reprogram(unsigned long next_tick)
-{
- omap_32k_timer_start(JIFFIES_TO_HW_TICKS(next_tick, 32768) + 1);
-}
-
-static struct irqaction omap_32k_timer_irq;
-extern struct timer_update_handler timer_update;
-
-static int omap_32k_timer_enable_dyn_tick(void)
-{
- /* No need to reprogram timer, just use the next interrupt */
- return 0;
-}
-
-static int omap_32k_timer_disable_dyn_tick(void)
-{
- omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD);
- return 0;
-}
-
-static struct dyn_tick_timer omap_dyn_tick_timer = {
- .enable = omap_32k_timer_enable_dyn_tick,
- .disable = omap_32k_timer_disable_dyn_tick,
- .reprogram = omap_32k_timer_reprogram,
- .handler = omap_32k_timer_interrupt,
-};
-#endif /* CONFIG_NO_IDLE_HZ */
-
static struct irqaction omap_32k_timer_irq = {
.name = "32KHz timer",
- .flags = SA_INTERRUPT | SA_TIMER,
+ .flags = IRQF_DISABLED | IRQF_TIMER,
.handler = omap_32k_timer_interrupt,
};
-static struct clk * gpt1_ick;
-static struct clk * gpt1_fck;
-
static __init void omap_init_32k_timer(void)
{
-#ifdef CONFIG_NO_IDLE_HZ
- omap_timer.dyn_tick = &omap_dyn_tick_timer;
-#endif
-
if (cpu_class_is_omap1())
setup_irq(INT_OS_TIMER, &omap_32k_timer_irq);
- if (cpu_is_omap24xx())
- setup_irq(37, &omap_32k_timer_irq);
- omap_timer.offset = omap_32k_timer_gettimeoffset;
omap_32k_last_tick = omap_32k_sync_timer_read();
+#ifdef CONFIG_ARCH_OMAP2
/* REVISIT: Check 24xx TIOCP_CFG settings after idle works */
if (cpu_is_omap24xx()) {
- omap_32k_timer_write(0, GP_TIMER_TCLR);
- omap_writel(0, CM_CLKSEL_WKUP); /* 32KHz clock source */
-
- gpt1_ick = clk_get(NULL, "gpt1_ick");
- if (IS_ERR(gpt1_ick))
- printk(KERN_ERR "Could not get gpt1_ick\n");
- else
- clk_enable(gpt1_ick);
-
- gpt1_fck = clk_get(NULL, "gpt1_fck");
- if (IS_ERR(gpt1_fck))
- printk(KERN_ERR "Could not get gpt1_fck\n");
- else
- clk_enable(gpt1_fck);
-
- mdelay(100); /* Wait for clocks to stabilize */
-
- omap_32k_timer_write(0x7, GP_TIMER_TISR);
+ gptimer = omap_dm_timer_request_specific(1);
+ BUG_ON(gptimer == NULL);
+
+ omap_dm_timer_set_source(gptimer, OMAP_TIMER_SRC_32_KHZ);
+ setup_irq(omap_dm_timer_get_irq(gptimer), &omap_32k_timer_irq);
+ omap_dm_timer_set_int_enable(gptimer,
+ OMAP_TIMER_INT_CAPTURE | OMAP_TIMER_INT_OVERFLOW |
+ OMAP_TIMER_INT_MATCH);
}
+#endif
- omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD);
+ clockevent_32k_timer.mult = div_sc(OMAP_32K_TICKS_PER_SEC,
+ NSEC_PER_SEC,
+ clockevent_32k_timer.shift);
+ clockevent_32k_timer.max_delta_ns =
+ clockevent_delta2ns(0xfffffffe, &clockevent_32k_timer);
+ clockevent_32k_timer.min_delta_ns =
+ clockevent_delta2ns(1, &clockevent_32k_timer);
+
+ clockevent_32k_timer.cpumask = cpumask_of_cpu(0);
+ clockevents_register_device(&clockevent_32k_timer);
}
/*
*/
static void __init omap_timer_init(void)
{
+#ifdef CONFIG_OMAP_DM_TIMER
+ omap_dm_timer_init();
+#endif
omap_init_32k_timer();
}
struct sys_timer omap_timer = {
.init = omap_timer_init,
- .offset = NULL, /* Initialized later */
};