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-rw-r--r--arch/microblaze/kernel/timer.c262
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
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+++ b/arch/microblaze/kernel/timer.c
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1/*
2 * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
3 * Copyright (C) 2007-2009 PetaLogix
4 * Copyright (C) 2006 Atmark Techno, Inc.
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10
11#include <linux/init.h>
12#include <linux/kernel.h>
13#include <linux/param.h>
14#include <linux/interrupt.h>
15#include <linux/profile.h>
16#include <linux/irq.h>
17#include <linux/delay.h>
18#include <linux/sched.h>
19#include <linux/spinlock.h>
20#include <linux/err.h>
21#include <linux/clk.h>
22#include <linux/clocksource.h>
23#include <linux/clockchips.h>
24#include <linux/io.h>
25#include <asm/cpuinfo.h>
26#include <asm/setup.h>
27#include <asm/prom.h>
28#include <asm/irq.h>
29#include <asm/system.h>
30
31#ifdef CONFIG_SELFMOD_TIMER
32#include <asm/selfmod.h>
33#define TIMER_BASE BARRIER_BASE_ADDR
34#else
35static unsigned int timer_baseaddr;
36#define TIMER_BASE timer_baseaddr
37#endif
38
39#define TCSR0 (0x00)
40#define TLR0 (0x04)
41#define TCR0 (0x08)
42#define TCSR1 (0x10)
43#define TLR1 (0x14)
44#define TCR1 (0x18)
45
46#define TCSR_MDT (1<<0)
47#define TCSR_UDT (1<<1)
48#define TCSR_GENT (1<<2)
49#define TCSR_CAPT (1<<3)
50#define TCSR_ARHT (1<<4)
51#define TCSR_LOAD (1<<5)
52#define TCSR_ENIT (1<<6)
53#define TCSR_ENT (1<<7)
54#define TCSR_TINT (1<<8)
55#define TCSR_PWMA (1<<9)
56#define TCSR_ENALL (1<<10)
57
58static inline void microblaze_timer0_stop(void)
59{
60 out_be32(TIMER_BASE + TCSR0, in_be32(TIMER_BASE + TCSR0) & ~TCSR_ENT);
61}
62
63static inline void microblaze_timer0_start_periodic(unsigned long load_val)
64{
65 if (!load_val)
66 load_val = 1;
67 out_be32(TIMER_BASE + TLR0, load_val); /* loading value to timer reg */
68
69 /* load the initial value */
70 out_be32(TIMER_BASE + TCSR0, TCSR_LOAD);
71
72 /* see timer data sheet for detail
73 * !ENALL - don't enable 'em all
74 * !PWMA - disable pwm
75 * TINT - clear interrupt status
76 * ENT- enable timer itself
77 * EINT - enable interrupt
78 * !LOAD - clear the bit to let go
79 * ARHT - auto reload
80 * !CAPT - no external trigger
81 * !GENT - no external signal
82 * UDT - set the timer as down counter
83 * !MDT0 - generate mode
84 */
85 out_be32(TIMER_BASE + TCSR0,
86 TCSR_TINT|TCSR_ENIT|TCSR_ENT|TCSR_ARHT|TCSR_UDT);
87}
88
89static inline void microblaze_timer0_start_oneshot(unsigned long load_val)
90{
91 if (!load_val)
92 load_val = 1;
93 out_be32(TIMER_BASE + TLR0, load_val); /* loading value to timer reg */
94
95 /* load the initial value */
96 out_be32(TIMER_BASE + TCSR0, TCSR_LOAD);
97
98 out_be32(TIMER_BASE + TCSR0,
99 TCSR_TINT|TCSR_ENIT|TCSR_ENT|TCSR_ARHT|TCSR_UDT);
100}
101
102static int microblaze_timer_set_next_event(unsigned long delta,
103 struct clock_event_device *dev)
104{
105 pr_debug("%s: next event, delta %x\n", __func__, (u32)delta);
106 microblaze_timer0_start_oneshot(delta);
107 return 0;
108}
109
110static void microblaze_timer_set_mode(enum clock_event_mode mode,
111 struct clock_event_device *evt)
112{
113 switch (mode) {
114 case CLOCK_EVT_MODE_PERIODIC:
115 printk(KERN_INFO "%s: periodic\n", __func__);
116 microblaze_timer0_start_periodic(cpuinfo.freq_div_hz);
117 break;
118 case CLOCK_EVT_MODE_ONESHOT:
119 printk(KERN_INFO "%s: oneshot\n", __func__);
120 break;
121 case CLOCK_EVT_MODE_UNUSED:
122 printk(KERN_INFO "%s: unused\n", __func__);
123 break;
124 case CLOCK_EVT_MODE_SHUTDOWN:
125 printk(KERN_INFO "%s: shutdown\n", __func__);
126 microblaze_timer0_stop();
127 break;
128 case CLOCK_EVT_MODE_RESUME:
129 printk(KERN_INFO "%s: resume\n", __func__);
130 break;
131 }
132}
133
134static struct clock_event_device clockevent_microblaze_timer = {
135 .name = "microblaze_clockevent",
136 .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
137 .shift = 24,
138 .rating = 300,
139 .set_next_event = microblaze_timer_set_next_event,
140 .set_mode = microblaze_timer_set_mode,
141};
142
143static inline void timer_ack(void)
144{
145 out_be32(TIMER_BASE + TCSR0, in_be32(TIMER_BASE + TCSR0));
146}
147
148static irqreturn_t timer_interrupt(int irq, void *dev_id)
149{
150 struct clock_event_device *evt = &clockevent_microblaze_timer;
151#ifdef CONFIG_HEART_BEAT
152 heartbeat();
153#endif
154 timer_ack();
155 evt->event_handler(evt);
156 return IRQ_HANDLED;
157}
158
159static struct irqaction timer_irqaction = {
160 .handler = timer_interrupt,
161 .flags = IRQF_DISABLED | IRQF_TIMER,
162 .name = "timer",
163 .dev_id = &clockevent_microblaze_timer,
164};
165
166static __init void microblaze_clockevent_init(void)
167{
168 clockevent_microblaze_timer.mult =
169 div_sc(cpuinfo.cpu_clock_freq, NSEC_PER_SEC,
170 clockevent_microblaze_timer.shift);
171 clockevent_microblaze_timer.max_delta_ns =
172 clockevent_delta2ns((u32)~0, &clockevent_microblaze_timer);
173 clockevent_microblaze_timer.min_delta_ns =
174 clockevent_delta2ns(1, &clockevent_microblaze_timer);
175 clockevent_microblaze_timer.cpumask = cpumask_of(0);
176 clockevents_register_device(&clockevent_microblaze_timer);
177}
178
179static cycle_t microblaze_read(void)
180{
181 /* reading actual value of timer 1 */
182 return (cycle_t) (in_be32(TIMER_BASE + TCR1));
183}
184
185static struct clocksource clocksource_microblaze = {
186 .name = "microblaze_clocksource",
187 .rating = 300,
188 .read = microblaze_read,
189 .mask = CLOCKSOURCE_MASK(32),
190 .shift = 24, /* I can shift it */
191 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
192};
193
194static int __init microblaze_clocksource_init(void)
195{
196 clocksource_microblaze.mult =
197 clocksource_hz2mult(cpuinfo.cpu_clock_freq,
198 clocksource_microblaze.shift);
199 if (clocksource_register(&clocksource_microblaze))
200 panic("failed to register clocksource");
201
202 /* stop timer1 */
203 out_be32(TIMER_BASE + TCSR1, in_be32(TIMER_BASE + TCSR1) & ~TCSR_ENT);
204 /* start timer1 - up counting without interrupt */
205 out_be32(TIMER_BASE + TCSR1, TCSR_TINT|TCSR_ENT|TCSR_ARHT);
206 return 0;
207}
208
209void __init time_init(void)
210{
211 u32 irq, i = 0;
212 u32 timer_num = 1;
213 struct device_node *timer = NULL;
214#ifdef CONFIG_SELFMOD_TIMER
215 unsigned int timer_baseaddr = 0;
216 int arr_func[] = {
217 (int)&microblaze_read,
218 (int)&timer_interrupt,
219 (int)&microblaze_clocksource_init,
220 (int)&microblaze_timer_set_mode,
221 (int)&microblaze_timer_set_next_event,
222 0
223 };
224#endif
225 char *timer_list[] = {
226 "xlnx,xps-timer-1.00.a",
227 "xlnx,opb-timer-1.00.b",
228 "xlnx,opb-timer-1.00.a",
229 NULL
230 };
231
232 for (i = 0; timer_list[i] != NULL; i++) {
233 timer = of_find_compatible_node(NULL, NULL, timer_list[i]);
234 if (timer)
235 break;
236 }
237
238 timer_baseaddr = *(int *) of_get_property(timer, "reg", NULL);
239 timer_baseaddr = (unsigned long) ioremap(timer_baseaddr, PAGE_SIZE);
240 irq = *(int *) of_get_property(timer, "interrupts", NULL);
241 timer_num =
242 *(int *) of_get_property(timer, "xlnx,one-timer-only", NULL);
243 if (timer_num) {
244 printk(KERN_EMERG "Please enable two timers in HW\n");
245 BUG();
246 }
247
248#ifdef CONFIG_SELFMOD_TIMER
249 selfmod_function((int *) arr_func, timer_baseaddr);
250#endif
251 printk(KERN_INFO "%s #0 at 0x%08x, irq=%d\n",
252 timer_list[i], timer_baseaddr, irq);
253
254 cpuinfo.freq_div_hz = cpuinfo.cpu_clock_freq / HZ;
255
256 setup_irq(irq, &timer_irqaction);
257#ifdef CONFIG_HEART_BEAT
258 setup_heartbeat();
259#endif
260 microblaze_clocksource_init();
261 microblaze_clockevent_init();
262}