diff options
Diffstat (limited to 'arch/microblaze/kernel/timer.c')
| -rw-r--r-- | arch/microblaze/kernel/timer.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/arch/microblaze/kernel/timer.c b/arch/microblaze/kernel/timer.c new file mode 100644 index 00000000000..bdfa2f9f0c8 --- /dev/null +++ b/arch/microblaze/kernel/timer.c @@ -0,0 +1,262 @@ +/* + * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu> + * Copyright (C) 2007-2009 PetaLogix + * Copyright (C) 2006 Atmark Techno, Inc. + * + * 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/kernel.h> +#include <linux/param.h> +#include <linux/interrupt.h> +#include <linux/profile.h> +#include <linux/irq.h> +#include <linux/delay.h> +#include <linux/sched.h> +#include <linux/spinlock.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> +#include <linux/io.h> +#include <asm/cpuinfo.h> +#include <asm/setup.h> +#include <asm/prom.h> +#include <asm/irq.h> +#include <asm/system.h> + +#ifdef CONFIG_SELFMOD_TIMER +#include <asm/selfmod.h> +#define TIMER_BASE BARRIER_BASE_ADDR +#else +static unsigned int timer_baseaddr; +#define TIMER_BASE timer_baseaddr +#endif + +#define TCSR0 (0x00) +#define TLR0 (0x04) +#define TCR0 (0x08) +#define TCSR1 (0x10) +#define TLR1 (0x14) +#define TCR1 (0x18) + +#define TCSR_MDT (1<<0) +#define TCSR_UDT (1<<1) +#define TCSR_GENT (1<<2) +#define TCSR_CAPT (1<<3) +#define TCSR_ARHT (1<<4) +#define TCSR_LOAD (1<<5) +#define TCSR_ENIT (1<<6) +#define TCSR_ENT (1<<7) +#define TCSR_TINT (1<<8) +#define TCSR_PWMA (1<<9) +#define TCSR_ENALL (1<<10) + +static inline void microblaze_timer0_stop(void) +{ + out_be32(TIMER_BASE + TCSR0, in_be32(TIMER_BASE + TCSR0) & ~TCSR_ENT); +} + +static inline void microblaze_timer0_start_periodic(unsigned long load_val) +{ + if (!load_val) + load_val = 1; + out_be32(TIMER_BASE + TLR0, load_val); /* loading value to timer reg */ + + /* load the initial value */ + out_be32(TIMER_BASE + TCSR0, TCSR_LOAD); + + /* see timer data sheet for detail + * !ENALL - don't enable 'em all + * !PWMA - disable pwm + * TINT - clear interrupt status + * ENT- enable timer itself + * EINT - enable interrupt + * !LOAD - clear the bit to let go + * ARHT - auto reload + * !CAPT - no external trigger + * !GENT - no external signal + * UDT - set the timer as down counter + * !MDT0 - generate mode + */ + out_be32(TIMER_BASE + TCSR0, + TCSR_TINT|TCSR_ENIT|TCSR_ENT|TCSR_ARHT|TCSR_UDT); +} + +static inline void microblaze_timer0_start_oneshot(unsigned long load_val) +{ + if (!load_val) + load_val = 1; + out_be32(TIMER_BASE + TLR0, load_val); /* loading value to timer reg */ + + /* load the initial value */ + out_be32(TIMER_BASE + TCSR0, TCSR_LOAD); + + out_be32(TIMER_BASE + TCSR0, + TCSR_TINT|TCSR_ENIT|TCSR_ENT|TCSR_ARHT|TCSR_UDT); +} + +static int microblaze_timer_set_next_event(unsigned long delta, + struct clock_event_device *dev) +{ + pr_debug("%s: next event, delta %x\n", __func__, (u32)delta); + microblaze_timer0_start_oneshot(delta); + return 0; +} + +static void microblaze_timer_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + printk(KERN_INFO "%s: periodic\n", __func__); + microblaze_timer0_start_periodic(cpuinfo.freq_div_hz); + break; + case CLOCK_EVT_MODE_ONESHOT: + printk(KERN_INFO "%s: oneshot\n", __func__); + break; + case CLOCK_EVT_MODE_UNUSED: + printk(KERN_INFO "%s: unused\n", __func__); + break; + case CLOCK_EVT_MODE_SHUTDOWN: + printk(KERN_INFO "%s: shutdown\n", __func__); + microblaze_timer0_stop(); + break; + case CLOCK_EVT_MODE_RESUME: + printk(KERN_INFO "%s: resume\n", __func__); + break; + } +} + +static struct clock_event_device clockevent_microblaze_timer = { + .name = "microblaze_clockevent", + .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC, + .shift = 24, + .rating = 300, + .set_next_event = microblaze_timer_set_next_event, + .set_mode = microblaze_timer_set_mode, +}; + +static inline void timer_ack(void) +{ + out_be32(TIMER_BASE + TCSR0, in_be32(TIMER_BASE + TCSR0)); +} + +static irqreturn_t timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evt = &clockevent_microblaze_timer; +#ifdef CONFIG_HEART_BEAT + heartbeat(); +#endif + timer_ack(); + evt->event_handler(evt); + return IRQ_HANDLED; +} + +static struct irqaction timer_irqaction = { + .handler = timer_interrupt, + .flags = IRQF_DISABLED | IRQF_TIMER, + .name = "timer", + .dev_id = &clockevent_microblaze_timer, +}; + +static __init void microblaze_clockevent_init(void) +{ + clockevent_microblaze_timer.mult = + div_sc(cpuinfo.cpu_clock_freq, NSEC_PER_SEC, + clockevent_microblaze_timer.shift); + clockevent_microblaze_timer.max_delta_ns = + clockevent_delta2ns((u32)~0, &clockevent_microblaze_timer); + clockevent_microblaze_timer.min_delta_ns = + clockevent_delta2ns(1, &clockevent_microblaze_timer); + clockevent_microblaze_timer.cpumask = cpumask_of(0); + clockevents_register_device(&clockevent_microblaze_timer); +} + +static cycle_t microblaze_read(struct clocksource *cs) +{ + /* reading actual value of timer 1 */ + return (cycle_t) (in_be32(TIMER_BASE + TCR1)); +} + +static struct clocksource clocksource_microblaze = { + .name = "microblaze_clocksource", + .rating = 300, + .read = microblaze_read, + .mask = CLOCKSOURCE_MASK(32), + .shift = 24, /* I can shift it */ + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +static int __init microblaze_clocksource_init(void) +{ + clocksource_microblaze.mult = + clocksource_hz2mult(cpuinfo.cpu_clock_freq, + clocksource_microblaze.shift); + if (clocksource_register(&clocksource_microblaze)) + panic("failed to register clocksource"); + + /* stop timer1 */ + out_be32(TIMER_BASE + TCSR1, in_be32(TIMER_BASE + TCSR1) & ~TCSR_ENT); + /* start timer1 - up counting without interrupt */ + out_be32(TIMER_BASE + TCSR1, TCSR_TINT|TCSR_ENT|TCSR_ARHT); + return 0; +} + +void __init time_init(void) +{ + u32 irq, i = 0; + u32 timer_num = 1; + struct device_node *timer = NULL; +#ifdef CONFIG_SELFMOD_TIMER + unsigned int timer_baseaddr = 0; + int arr_func[] = { + (int)µblaze_read, + (int)&timer_interrupt, + (int)µblaze_clocksource_init, + (int)µblaze_timer_set_mode, + (int)µblaze_timer_set_next_event, + 0 + }; +#endif + char *timer_list[] = { + "xlnx,xps-timer-1.00.a", + "xlnx,opb-timer-1.00.b", + "xlnx,opb-timer-1.00.a", + NULL + }; + + for (i = 0; timer_list[i] != NULL; i++) { + timer = of_find_compatible_node(NULL, NULL, timer_list[i]); + if (timer) + break; + } + + timer_baseaddr = *(int *) of_get_property(timer, "reg", NULL); + timer_baseaddr = (unsigned long) ioremap(timer_baseaddr, PAGE_SIZE); + irq = *(int *) of_get_property(timer, "interrupts", NULL); + timer_num = + *(int *) of_get_property(timer, "xlnx,one-timer-only", NULL); + if (timer_num) { + printk(KERN_EMERG "Please enable two timers in HW\n"); + BUG(); + } + +#ifdef CONFIG_SELFMOD_TIMER + selfmod_function((int *) arr_func, timer_baseaddr); +#endif + printk(KERN_INFO "%s #0 at 0x%08x, irq=%d\n", + timer_list[i], timer_baseaddr, irq); + + cpuinfo.freq_div_hz = cpuinfo.cpu_clock_freq / HZ; + + setup_irq(irq, &timer_irqaction); +#ifdef CONFIG_HEART_BEAT + setup_heartbeat(); +#endif + microblaze_clocksource_init(); + microblaze_clockevent_init(); +} |