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diff --git a/arch/arm/mach-omap1/time.c b/arch/arm/mach-omap1/time.c
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+/*
+ * linux/arch/arm/mach-omap1/time.c
+ *
+ * OMAP Timers
+ *
+ * Copyright (C) 2004 Nokia Corporation
+ * Partial timer rewrite and additional dynamic tick timer support by
+ * Tony Lindgen <tony@atomide.com> and
+ * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
+ *
+ * MPU timer code based on the older MPU timer code for OMAP
+ * Copyright (C) 2000 RidgeRun, Inc.
+ * Author: Greg Lonnon <glonnon@ridgerun.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/io.h>
+
+#include <asm/system.h>
+#include <mach/hardware.h>
+#include <asm/leds.h>
+#include <asm/irq.h>
+#include <asm/sched_clock.h>
+
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+#include <plat/common.h>
+
+#ifdef CONFIG_OMAP_MPU_TIMER
+
+#define OMAP_MPU_TIMER_BASE OMAP_MPU_TIMER1_BASE
+#define OMAP_MPU_TIMER_OFFSET 0x100
+
+typedef struct {
+ u32 cntl; /* CNTL_TIMER, R/W */
+ u32 load_tim; /* LOAD_TIM, W */
+ u32 read_tim; /* READ_TIM, R */
+} omap_mpu_timer_regs_t;
+
+#define omap_mpu_timer_base(n) \
+((omap_mpu_timer_regs_t __iomem *)OMAP1_IO_ADDRESS(OMAP_MPU_TIMER_BASE + \
+ (n)*OMAP_MPU_TIMER_OFFSET))
+
+static inline unsigned long notrace omap_mpu_timer_read(int nr)
+{
+ omap_mpu_timer_regs_t __iomem *timer = omap_mpu_timer_base(nr);
+ return readl(&timer->read_tim);
+}
+
+static inline void omap_mpu_set_autoreset(int nr)
+{
+ omap_mpu_timer_regs_t __iomem *timer = omap_mpu_timer_base(nr);
+
+ writel(readl(&timer->cntl) | MPU_TIMER_AR, &timer->cntl);
+}
+
+static inline void omap_mpu_remove_autoreset(int nr)
+{
+ omap_mpu_timer_regs_t __iomem *timer = omap_mpu_timer_base(nr);
+
+ writel(readl(&timer->cntl) & ~MPU_TIMER_AR, &timer->cntl);
+}
+
+static inline void omap_mpu_timer_start(int nr, unsigned long load_val,
+ int autoreset)
+{
+ omap_mpu_timer_regs_t __iomem *timer = omap_mpu_timer_base(nr);
+ unsigned int timerflags = MPU_TIMER_CLOCK_ENABLE | MPU_TIMER_ST;
+
+ if (autoreset)
+ timerflags |= MPU_TIMER_AR;
+
+ writel(MPU_TIMER_CLOCK_ENABLE, &timer->cntl);
+ udelay(1);
+ writel(load_val, &timer->load_tim);
+ udelay(1);
+ writel(timerflags, &timer->cntl);
+}
+
+static inline void omap_mpu_timer_stop(int nr)
+{
+ omap_mpu_timer_regs_t __iomem *timer = omap_mpu_timer_base(nr);
+
+ writel(readl(&timer->cntl) & ~MPU_TIMER_ST, &timer->cntl);
+}
+
+/*
+ * ---------------------------------------------------------------------------
+ * MPU timer 1 ... count down to zero, interrupt, reload
+ * ---------------------------------------------------------------------------
+ */
+static int omap_mpu_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ omap_mpu_timer_start(0, cycles, 0);
+ return 0;
+}
+
+static void omap_mpu_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ omap_mpu_set_autoreset(0);
+ break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ omap_mpu_timer_stop(0);
+ omap_mpu_remove_autoreset(0);
+ break;
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_RESUME:
+ break;
+ }
+}
+
+static struct clock_event_device clockevent_mpu_timer1 = {
+ .name = "mpu_timer1",
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .shift = 32,
+ .set_next_event = omap_mpu_set_next_event,
+ .set_mode = omap_mpu_set_mode,
+};
+
+static irqreturn_t omap_mpu_timer1_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = &clockevent_mpu_timer1;
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction omap_mpu_timer1_irq = {
+ .name = "mpu_timer1",
+ .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+ .handler = omap_mpu_timer1_interrupt,
+};
+
+static __init void omap_init_mpu_timer(unsigned long rate)
+{
+ setup_irq(INT_TIMER1, &omap_mpu_timer1_irq);
+ omap_mpu_timer_start(0, (rate / HZ) - 1, 1);
+
+ clockevent_mpu_timer1.mult = div_sc(rate, NSEC_PER_SEC,
+ clockevent_mpu_timer1.shift);
+ clockevent_mpu_timer1.max_delta_ns =
+ clockevent_delta2ns(-1, &clockevent_mpu_timer1);
+ clockevent_mpu_timer1.min_delta_ns =
+ clockevent_delta2ns(1, &clockevent_mpu_timer1);
+
+ clockevent_mpu_timer1.cpumask = cpumask_of(0);
+ clockevents_register_device(&clockevent_mpu_timer1);
+}
+
+
+/*
+ * ---------------------------------------------------------------------------
+ * MPU timer 2 ... free running 32-bit clock source and scheduler clock
+ * ---------------------------------------------------------------------------
+ */
+
+static DEFINE_CLOCK_DATA(cd);
+
+static inline unsigned long long notrace _omap_mpu_sched_clock(void)
+{
+ u32 cyc = ~omap_mpu_timer_read(1);
+ return cyc_to_sched_clock(&cd, cyc, (u32)~0);
+}
+
+#ifndef CONFIG_OMAP_32K_TIMER
+unsigned long long notrace sched_clock(void)
+{
+ return _omap_mpu_sched_clock();
+}
+#else
+static unsigned long long notrace omap_mpu_sched_clock(void)
+{
+ return _omap_mpu_sched_clock();
+}
+#endif
+
+static void notrace mpu_update_sched_clock(void)
+{
+ u32 cyc = ~omap_mpu_timer_read(1);
+ update_sched_clock(&cd, cyc, (u32)~0);
+}
+
+static void __init omap_init_clocksource(unsigned long rate)
+{
+ omap_mpu_timer_regs_t __iomem *timer = omap_mpu_timer_base(1);
+ static char err[] __initdata = KERN_ERR
+ "%s: can't register clocksource!\n";
+
+ omap_mpu_timer_start(1, ~0, 1);
+ init_sched_clock(&cd, mpu_update_sched_clock, 32, rate);
+
+ if (clocksource_mmio_init(&timer->read_tim, "mpu_timer2", rate,
+ 300, 32, clocksource_mmio_readl_down))
+ printk(err, "mpu_timer2");
+}
+
+static void __init omap_mpu_timer_init(void)
+{
+ struct clk *ck_ref = clk_get(NULL, "ck_ref");
+ unsigned long rate;
+
+ BUG_ON(IS_ERR(ck_ref));
+
+ rate = clk_get_rate(ck_ref);
+ clk_put(ck_ref);
+
+ /* PTV = 0 */
+ rate /= 2;
+
+ omap_init_mpu_timer(rate);
+ omap_init_clocksource(rate);
+}
+
+#else
+static inline void omap_mpu_timer_init(void)
+{
+ pr_err("Bogus timer, should not happen\n");
+}
+#endif /* CONFIG_OMAP_MPU_TIMER */
+
+#if defined(CONFIG_OMAP_MPU_TIMER) && defined(CONFIG_OMAP_32K_TIMER)
+static unsigned long long (*preferred_sched_clock)(void);
+
+unsigned long long notrace sched_clock(void)
+{
+ if (!preferred_sched_clock)
+ return 0;
+
+ return preferred_sched_clock();
+}
+
+static inline void preferred_sched_clock_init(bool use_32k_sched_clock)
+{
+ if (use_32k_sched_clock)
+ preferred_sched_clock = omap_32k_sched_clock;
+ else
+ preferred_sched_clock = omap_mpu_sched_clock;
+}
+#else
+static inline void preferred_sched_clock_init(bool use_32k_sched_clcok)
+{
+}
+#endif
+
+static inline int omap_32k_timer_usable(void)
+{
+ int res = false;
+
+ if (cpu_is_omap730() || cpu_is_omap15xx())
+ return res;
+
+#ifdef CONFIG_OMAP_32K_TIMER
+ res = omap_32k_timer_init();
+#endif
+
+ return res;
+}
+
+/*
+ * ---------------------------------------------------------------------------
+ * Timer initialization
+ * ---------------------------------------------------------------------------
+ */
+static void __init omap_timer_init(void)
+{
+ if (omap_32k_timer_usable()) {
+ preferred_sched_clock_init(1);
+ } else {
+ omap_mpu_timer_init();
+ preferred_sched_clock_init(0);
+ }
+}
+
+struct sys_timer omap_timer = {
+ .init = omap_timer_init,
+};
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-09 06:46:35 +0000