diff options
Diffstat (limited to 'arch/arm/plat-versatile/timer-sp.c')
| -rw-r--r-- | arch/arm/plat-versatile/timer-sp.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/arch/arm/plat-versatile/timer-sp.c b/arch/arm/plat-versatile/timer-sp.c new file mode 100644 index 000000000000..fb0d1c299718 --- /dev/null +++ b/arch/arm/plat-versatile/timer-sp.c | |||
| @@ -0,0 +1,156 @@ | |||
| 1 | /* | ||
| 2 | * linux/arch/arm/plat-versatile/timer-sp.c | ||
| 3 | * | ||
| 4 | * Copyright (C) 1999 - 2003 ARM Limited | ||
| 5 | * Copyright (C) 2000 Deep Blue Solutions Ltd | ||
| 6 | * | ||
| 7 | * This program is free software; you can redistribute it and/or modify | ||
| 8 | * it under the terms of the GNU General Public License as published by | ||
| 9 | * the Free Software Foundation; either version 2 of the License, or | ||
| 10 | * (at your option) any later version. | ||
| 11 | * | ||
| 12 | * This program is distributed in the hope that it will be useful, | ||
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
| 15 | * GNU General Public License for more details. | ||
| 16 | * | ||
| 17 | * You should have received a copy of the GNU General Public License | ||
| 18 | * along with this program; if not, write to the Free Software | ||
| 19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||
| 20 | */ | ||
| 21 | #include <linux/clocksource.h> | ||
| 22 | #include <linux/clockchips.h> | ||
| 23 | #include <linux/interrupt.h> | ||
| 24 | #include <linux/irq.h> | ||
| 25 | #include <linux/io.h> | ||
| 26 | |||
| 27 | #include <asm/hardware/arm_timer.h> | ||
| 28 | |||
| 29 | #include <plat/timer-sp.h> | ||
| 30 | |||
| 31 | /* | ||
| 32 | * These timers are currently always setup to be clocked at 1MHz. | ||
| 33 | */ | ||
| 34 | #define TIMER_FREQ_KHZ (1000) | ||
| 35 | #define TIMER_RELOAD (TIMER_FREQ_KHZ * 1000 / HZ) | ||
| 36 | |||
| 37 | static void __iomem *clksrc_base; | ||
| 38 | |||
| 39 | static cycle_t sp804_read(struct clocksource *cs) | ||
| 40 | { | ||
| 41 | return ~readl(clksrc_base + TIMER_VALUE); | ||
| 42 | } | ||
| 43 | |||
| 44 | static struct clocksource clocksource_sp804 = { | ||
| 45 | .name = "timer3", | ||
| 46 | .rating = 200, | ||
| 47 | .read = sp804_read, | ||
| 48 | .mask = CLOCKSOURCE_MASK(32), | ||
| 49 | .shift = 20, | ||
| 50 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | ||
| 51 | }; | ||
| 52 | |||
| 53 | void __init sp804_clocksource_init(void __iomem *base) | ||
| 54 | { | ||
| 55 | struct clocksource *cs = &clocksource_sp804; | ||
| 56 | |||
| 57 | clksrc_base = base; | ||
| 58 | |||
| 59 | /* setup timer 0 as free-running clocksource */ | ||
| 60 | writel(0, clksrc_base + TIMER_CTRL); | ||
| 61 | writel(0xffffffff, clksrc_base + TIMER_LOAD); | ||
| 62 | writel(0xffffffff, clksrc_base + TIMER_VALUE); | ||
| 63 | writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC, | ||
| 64 | clksrc_base + TIMER_CTRL); | ||
| 65 | |||
| 66 | cs->mult = clocksource_khz2mult(TIMER_FREQ_KHZ, cs->shift); | ||
| 67 | clocksource_register(cs); | ||
| 68 | } | ||
| 69 | |||
| 70 | |||
| 71 | static void __iomem *clkevt_base; | ||
| 72 | |||
| 73 | /* | ||
| 74 | * IRQ handler for the timer | ||
| 75 | */ | ||
| 76 | static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id) | ||
| 77 | { | ||
| 78 | struct clock_event_device *evt = dev_id; | ||
| 79 | |||
| 80 | /* clear the interrupt */ | ||
| 81 | writel(1, clkevt_base + TIMER_INTCLR); | ||
| 82 | |||
| 83 | evt->event_handler(evt); | ||
| 84 | |||
| 85 | return IRQ_HANDLED; | ||
| 86 | } | ||
| 87 | |||
| 88 | static void sp804_set_mode(enum clock_event_mode mode, | ||
| 89 | struct clock_event_device *evt) | ||
| 90 | { | ||
| 91 | unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE; | ||
| 92 | |||
| 93 | writel(ctrl, clkevt_base + TIMER_CTRL); | ||
| 94 | |||
| 95 | switch (mode) { | ||
| 96 | case CLOCK_EVT_MODE_PERIODIC: | ||
| 97 | writel(TIMER_RELOAD, clkevt_base + TIMER_LOAD); | ||
| 98 | ctrl |= TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE; | ||
| 99 | break; | ||
| 100 | |||
| 101 | case CLOCK_EVT_MODE_ONESHOT: | ||
| 102 | /* period set, and timer enabled in 'next_event' hook */ | ||
| 103 | ctrl |= TIMER_CTRL_ONESHOT; | ||
| 104 | break; | ||
| 105 | |||
| 106 | case CLOCK_EVT_MODE_UNUSED: | ||
| 107 | case CLOCK_EVT_MODE_SHUTDOWN: | ||
| 108 | default: | ||
| 109 | break; | ||
| 110 | } | ||
| 111 | |||
| 112 | writel(ctrl, clkevt_base + TIMER_CTRL); | ||
| 113 | } | ||
| 114 | |||
| 115 | static int sp804_set_next_event(unsigned long next, | ||
| 116 | struct clock_event_device *evt) | ||
| 117 | { | ||
| 118 | unsigned long ctrl = readl(clkevt_base + TIMER_CTRL); | ||
| 119 | |||
| 120 | writel(next, clkevt_base + TIMER_LOAD); | ||
| 121 | writel(ctrl | TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL); | ||
| 122 | |||
| 123 | return 0; | ||
| 124 | } | ||
| 125 | |||
| 126 | static struct clock_event_device sp804_clockevent = { | ||
| 127 | .name = "timer0", | ||
| 128 | .shift = 32, | ||
| 129 | .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, | ||
| 130 | .set_mode = sp804_set_mode, | ||
| 131 | .set_next_event = sp804_set_next_event, | ||
| 132 | .rating = 300, | ||
| 133 | .cpumask = cpu_all_mask, | ||
| 134 | }; | ||
| 135 | |||
| 136 | static struct irqaction sp804_timer_irq = { | ||
| 137 | .name = "timer", | ||
| 138 | .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, | ||
| 139 | .handler = sp804_timer_interrupt, | ||
| 140 | .dev_id = &sp804_clockevent, | ||
| 141 | }; | ||
| 142 | |||
| 143 | void __init sp804_clockevents_init(void __iomem *base, unsigned int timer_irq) | ||
| 144 | { | ||
| 145 | struct clock_event_device *evt = &sp804_clockevent; | ||
| 146 | |||
| 147 | clkevt_base = base; | ||
| 148 | |||
| 149 | evt->irq = timer_irq; | ||
| 150 | evt->mult = div_sc(TIMER_FREQ_KHZ, NSEC_PER_MSEC, evt->shift); | ||
| 151 | evt->max_delta_ns = clockevent_delta2ns(0xffffffff, evt); | ||
| 152 | evt->min_delta_ns = clockevent_delta2ns(0xf, evt); | ||
| 153 | |||
| 154 | setup_irq(timer_irq, &sp804_timer_irq); | ||
| 155 | clockevents_register_device(evt); | ||
| 156 | } | ||
