| /* |
| * 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 <linux/slab.h> |
| |
| #include <asm/mach/time.h> |
| #include <plat/dmtimer.h> |
| #include <asm/smp_twd.h> |
| #include <asm/sched_clock.h> |
| #include "common.h" |
| #include <plat/omap_hwmod.h> |
| #include <plat/omap_device.h> |
| #include <plat/omap-pm.h> |
| |
| #include "powerdomain.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 |
| |
| /* 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, 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, 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, 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, OMAP_TIMER_LOAD_REG, |
| 0xffffffff - period, 1); |
| __omap_dm_timer_load_start(&clkev, |
| 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, |
| .rating = 300, |
| .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; |
| struct resource irq_rsrc, mem_rsrc; |
| size_t size; |
| int res = 0; |
| int r; |
| |
| sprintf(name, "timer%d", gptimer_id); |
| omap_hwmod_setup_one(name); |
| oh = omap_hwmod_lookup(name); |
| if (!oh) |
| return -ENODEV; |
| |
| r = omap_hwmod_get_resource_byname(oh, IORESOURCE_IRQ, NULL, &irq_rsrc); |
| if (r) |
| return -ENXIO; |
| timer->irq = irq_rsrc.start; |
| |
| r = omap_hwmod_get_resource_byname(oh, IORESOURCE_MEM, NULL, &mem_rsrc); |
| if (r) |
| return -ENXIO; |
| timer->phys_base = mem_rsrc.start; |
| size = mem_rsrc.end - mem_rsrc.start; |
| |
| /* 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 */ |
| timer->fclk = clk_get(NULL, omap_hwmod_get_main_clk(oh)); |
| if (IS_ERR(timer->fclk)) |
| return -ENODEV; |
| |
| omap_hwmod_enable(oh); |
| |
| if (omap_dm_timer_reserve_systimer(gptimer_id)) |
| return -ENODEV; |
| |
| 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_init_regs(timer); |
| __omap_dm_timer_reset(timer, 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, 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 = cpu_possible_mask; |
| clockevent_gpt.irq = omap_dm_timer_get_irq(&clkev); |
| clockevents_register_device(&clockevent_gpt); |
| |
| pr_info("OMAP clockevent source: GPTIMER%d at %lu Hz\n", |
| gptimer_id, clkev.rate); |
| } |
| |
| /* Clocksource code */ |
| static struct omap_dm_timer clksrc; |
| static bool use_gptimer_clksrc; |
| |
| /* |
| * clocksource |
| */ |
| static cycle_t clocksource_read_cycles(struct clocksource *cs) |
| { |
| return (cycle_t)__omap_dm_timer_read_counter(&clksrc, 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 u32 notrace dmtimer_read_sched_clock(void) |
| { |
| if (clksrc.reserved) |
| return __omap_dm_timer_read_counter(&clksrc, 1); |
| |
| return 0; |
| } |
| |
| /* Setup free-running counter for clocksource */ |
| static int __init omap2_sync32k_clocksource_init(void) |
| { |
| int ret; |
| struct omap_hwmod *oh; |
| void __iomem *vbase; |
| const char *oh_name = "counter_32k"; |
| |
| /* |
| * First check hwmod data is available for sync32k counter |
| */ |
| oh = omap_hwmod_lookup(oh_name); |
| if (!oh || oh->slaves_cnt == 0) |
| return -ENODEV; |
| |
| omap_hwmod_setup_one(oh_name); |
| |
| vbase = omap_hwmod_get_mpu_rt_va(oh); |
| if (!vbase) { |
| pr_warn("%s: failed to get counter_32k resource\n", __func__); |
| return -ENXIO; |
| } |
| |
| ret = omap_hwmod_enable(oh); |
| if (ret) { |
| pr_warn("%s: failed to enable counter_32k module (%d)\n", |
| __func__, ret); |
| return ret; |
| } |
| |
| ret = omap_init_clocksource_32k(vbase); |
| if (ret) { |
| pr_warn("%s: failed to initialize counter_32k as a clocksource (%d)\n", |
| __func__, ret); |
| omap_hwmod_idle(oh); |
| } |
| |
| return ret; |
| } |
| |
| static void __init omap2_gptimer_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); |
| |
| __omap_dm_timer_load_start(&clksrc, |
| OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0, 1); |
| setup_sched_clock(dmtimer_read_sched_clock, 32, clksrc.rate); |
| |
| if (clocksource_register_hz(&clocksource_gpt, clksrc.rate)) |
| pr_err("Could not register clocksource %s\n", |
| clocksource_gpt.name); |
| else |
| pr_info("OMAP clocksource: GPTIMER%d at %lu Hz\n", |
| gptimer_id, clksrc.rate); |
| } |
| |
| static void __init omap2_clocksource_init(int gptimer_id, |
| const char *fck_source) |
| { |
| /* |
| * First give preference to kernel parameter configuration |
| * by user (clocksource="gp_timer"). |
| * |
| * In case of missing kernel parameter for clocksource, |
| * first check for availability for 32k-sync timer, in case |
| * of failure in finding 32k_counter module or registering |
| * it as clocksource, execution will fallback to gp-timer. |
| */ |
| if (use_gptimer_clksrc == true) |
| omap2_gptimer_clocksource_init(gptimer_id, fck_source); |
| else if (omap2_sync32k_clocksource_init()) |
| /* Fall back to gp-timer code */ |
| omap2_gptimer_clocksource_init(gptimer_id, fck_source); |
| } |
| |
| #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_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_SOC_AM33XX |
| OMAP_SYS_TIMER_INIT(3_am33xx, 1, OMAP4_MPU_SOURCE, 2, OMAP4_MPU_SOURCE) |
| OMAP_SYS_TIMER(3_am33xx) |
| #endif |
| |
| #ifdef CONFIG_ARCH_OMAP4 |
| #ifdef CONFIG_LOCAL_TIMERS |
| static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, |
| OMAP44XX_LOCAL_TWD_BASE, |
| OMAP44XX_IRQ_LOCALTIMER); |
| #endif |
| |
| static void __init omap4_timer_init(void) |
| { |
| omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE); |
| omap2_clocksource_init(2, OMAP4_MPU_SOURCE); |
| #ifdef CONFIG_LOCAL_TIMERS |
| /* Local timers are not supprted on OMAP4430 ES1.0 */ |
| if (omap_rev() != OMAP4430_REV_ES1_0) { |
| int err; |
| |
| err = twd_local_timer_register(&twd_local_timer); |
| if (err) |
| pr_err("twd_local_timer_register failed %d\n", err); |
| } |
| #endif |
| } |
| OMAP_SYS_TIMER(4) |
| #endif |
| |
| #ifdef CONFIG_SOC_OMAP5 |
| OMAP_SYS_TIMER_INIT(5, 1, OMAP4_CLKEV_SOURCE, 2, OMAP4_MPU_SOURCE) |
| OMAP_SYS_TIMER(5) |
| #endif |
| |
| /** |
| * omap_timer_init - build and register timer device with an |
| * associated timer hwmod |
| * @oh: timer hwmod pointer to be used to build timer device |
| * @user: parameter that can be passed from calling hwmod API |
| * |
| * Called by omap_hwmod_for_each_by_class to register each of the timer |
| * devices present in the system. The number of timer devices is known |
| * by parsing through the hwmod database for a given class name. At the |
| * end of function call memory is allocated for timer device and it is |
| * registered to the framework ready to be proved by the driver. |
| */ |
| static int __init omap_timer_init(struct omap_hwmod *oh, void *unused) |
| { |
| int id; |
| int ret = 0; |
| char *name = "omap_timer"; |
| struct dmtimer_platform_data *pdata; |
| struct platform_device *pdev; |
| struct omap_timer_capability_dev_attr *timer_dev_attr; |
| |
| pr_debug("%s: %s\n", __func__, oh->name); |
| |
| /* on secure device, do not register secure timer */ |
| timer_dev_attr = oh->dev_attr; |
| if (omap_type() != OMAP2_DEVICE_TYPE_GP && timer_dev_attr) |
| if (timer_dev_attr->timer_capability == OMAP_TIMER_SECURE) |
| return ret; |
| |
| pdata = kzalloc(sizeof(*pdata), GFP_KERNEL); |
| if (!pdata) { |
| pr_err("%s: No memory for [%s]\n", __func__, oh->name); |
| return -ENOMEM; |
| } |
| |
| /* |
| * Extract the IDs from name field in hwmod database |
| * and use the same for constructing ids' for the |
| * timer devices. In a way, we are avoiding usage of |
| * static variable witin the function to do the same. |
| * CAUTION: We have to be careful and make sure the |
| * name in hwmod database does not change in which case |
| * we might either make corresponding change here or |
| * switch back static variable mechanism. |
| */ |
| sscanf(oh->name, "timer%2d", &id); |
| |
| if (timer_dev_attr) |
| pdata->timer_capability = timer_dev_attr->timer_capability; |
| |
| pdev = omap_device_build(name, id, oh, pdata, sizeof(*pdata), |
| NULL, 0, 0); |
| |
| if (IS_ERR(pdev)) { |
| pr_err("%s: Can't build omap_device for %s: %s.\n", |
| __func__, name, oh->name); |
| ret = -EINVAL; |
| } |
| |
| kfree(pdata); |
| |
| return ret; |
| } |
| |
| /** |
| * omap2_dm_timer_init - top level regular device initialization |
| * |
| * Uses dedicated hwmod api to parse through hwmod database for |
| * given class name and then build and register the timer device. |
| */ |
| static int __init omap2_dm_timer_init(void) |
| { |
| int ret; |
| |
| ret = omap_hwmod_for_each_by_class("timer", omap_timer_init, NULL); |
| if (unlikely(ret)) { |
| pr_err("%s: device registration failed.\n", __func__); |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| arch_initcall(omap2_dm_timer_init); |
| |
| /** |
| * omap2_override_clocksource - clocksource override with user configuration |
| * |
| * Allows user to override default clocksource, using kernel parameter |
| * clocksource="gp_timer" (For all OMAP2PLUS architectures) |
| * |
| * Note that, here we are using same standard kernel parameter "clocksource=", |
| * and not introducing any OMAP specific interface. |
| */ |
| static int __init omap2_override_clocksource(char *str) |
| { |
| if (!str) |
| return 0; |
| /* |
| * For OMAP architecture, we only have two options |
| * - sync_32k (default) |
| * - gp_timer (sys_clk based) |
| */ |
| if (!strcmp(str, "gp_timer")) |
| use_gptimer_clksrc = true; |
| |
| return 0; |
| } |
| early_param("clocksource", omap2_override_clocksource); |