| /* |
| * 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, |
| }; |