/* * 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 | OMAP_TIMER_CTRL_AR, 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