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1/*
2 * linux/arch/arm/mach-mmp/time.c
3 *
4 * Support for clocksource and clockevents
5 *
6 * Copyright (C) 2008 Marvell International Ltd.
7 * All rights reserved.
8 *
9 * 2008-04-11: Jason Chagas <Jason.chagas@marvell.com>
10 * 2008-10-08: Bin Yang <bin.yang@marvell.com>
11 *
12 * The timers module actually includes three timers, each timer with up to
13 * three match comparators. Timer #0 is used here in free-running mode as
14 * the clock source, and match comparator #1 used as clock event device.
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License version 2 as
18 * published by the Free Software Foundation.
19 */
20
21#include <linux/init.h>
22#include <linux/kernel.h>
23#include <linux/interrupt.h>
24#include <linux/clockchips.h>
25
26#include <linux/io.h>
27#include <linux/irq.h>
28#include <linux/of.h>
29#include <linux/of_address.h>
30#include <linux/of_irq.h>
31
32#include <asm/sched_clock.h>
33#include <mach/addr-map.h>
34#include <mach/regs-timers.h>
35#include <mach/regs-apbc.h>
36#include <mach/irqs.h>
37#include <mach/cputype.h>
38#include <asm/mach/time.h>
39
40#include "clock.h"
41
42#define TIMERS_VIRT_BASE TIMERS1_VIRT_BASE
43
44#define MAX_DELTA (0xfffffffe)
45#define MIN_DELTA (16)
46
47static void __iomem *mmp_timer_base = TIMERS_VIRT_BASE;
48
49/*
50 * FIXME: the timer needs some delay to stablize the counter capture
51 */
52static inline uint32_t timer_read(void)
53{
54 int delay = 100;
55
56 __raw_writel(1, mmp_timer_base + TMR_CVWR(1));
57
58 while (delay--)
59 cpu_relax();
60
61 return __raw_readl(mmp_timer_base + TMR_CVWR(1));
62}
63
64static u32 notrace mmp_read_sched_clock(void)
65{
66 return timer_read();
67}
68
69static irqreturn_t timer_interrupt(int irq, void *dev_id)
70{
71 struct clock_event_device *c = dev_id;
72
73 /*
74 * Clear pending interrupt status.
75 */
76 __raw_writel(0x01, mmp_timer_base + TMR_ICR(0));
77
78 /*
79 * Disable timer 0.
80 */
81 __raw_writel(0x02, mmp_timer_base + TMR_CER);
82
83 c->event_handler(c);
84
85 return IRQ_HANDLED;
86}
87
88static int timer_set_next_event(unsigned long delta,
89 struct clock_event_device *dev)
90{
91 unsigned long flags;
92
93 local_irq_save(flags);
94
95 /*
96 * Disable timer 0.
97 */
98 __raw_writel(0x02, mmp_timer_base + TMR_CER);
99
100 /*
101 * Clear and enable timer match 0 interrupt.
102 */
103 __raw_writel(0x01, mmp_timer_base + TMR_ICR(0));
104 __raw_writel(0x01, mmp_timer_base + TMR_IER(0));
105
106 /*
107 * Setup new clockevent timer value.
108 */
109 __raw_writel(delta - 1, mmp_timer_base + TMR_TN_MM(0, 0));
110
111 /*
112 * Enable timer 0.
113 */
114 __raw_writel(0x03, mmp_timer_base + TMR_CER);
115
116 local_irq_restore(flags);
117
118 return 0;
119}
120
121static void timer_set_mode(enum clock_event_mode mode,
122 struct clock_event_device *dev)
123{
124 unsigned long flags;
125
126 local_irq_save(flags);
127 switch (mode) {
128 case CLOCK_EVT_MODE_ONESHOT:
129 case CLOCK_EVT_MODE_UNUSED:
130 case CLOCK_EVT_MODE_SHUTDOWN:
131 /* disable the matching interrupt */
132 __raw_writel(0x00, mmp_timer_base + TMR_IER(0));
133 break;
134 case CLOCK_EVT_MODE_RESUME:
135 case CLOCK_EVT_MODE_PERIODIC:
136 break;
137 }
138 local_irq_restore(flags);
139}
140
141static struct clock_event_device ckevt = {
142 .name = "clockevent",
143 .features = CLOCK_EVT_FEAT_ONESHOT,
144 .shift = 32,
145 .rating = 200,
146 .set_next_event = timer_set_next_event,
147 .set_mode = timer_set_mode,
148};
149
150static cycle_t clksrc_read(struct clocksource *cs)
151{
152 return timer_read();
153}
154
155static struct clocksource cksrc = {
156 .name = "clocksource",
157 .rating = 200,
158 .read = clksrc_read,
159 .mask = CLOCKSOURCE_MASK(32),
160 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
161};
162
163static void __init timer_config(void)
164{
165 uint32_t ccr = __raw_readl(mmp_timer_base + TMR_CCR);
166
167 __raw_writel(0x0, mmp_timer_base + TMR_CER); /* disable */
168
169 ccr &= (cpu_is_mmp2()) ? (TMR_CCR_CS_0(0) | TMR_CCR_CS_1(0)) :
170 (TMR_CCR_CS_0(3) | TMR_CCR_CS_1(3));
171 __raw_writel(ccr, mmp_timer_base + TMR_CCR);
172
173 /* set timer 0 to periodic mode, and timer 1 to free-running mode */
174 __raw_writel(0x2, mmp_timer_base + TMR_CMR);
175
176 __raw_writel(0x1, mmp_timer_base + TMR_PLCR(0)); /* periodic */
177 __raw_writel(0x7, mmp_timer_base + TMR_ICR(0)); /* clear status */
178 __raw_writel(0x0, mmp_timer_base + TMR_IER(0));
179
180 __raw_writel(0x0, mmp_timer_base + TMR_PLCR(1)); /* free-running */
181 __raw_writel(0x7, mmp_timer_base + TMR_ICR(1)); /* clear status */
182 __raw_writel(0x0, mmp_timer_base + TMR_IER(1));
183
184 /* enable timer 1 counter */
185 __raw_writel(0x2, mmp_timer_base + TMR_CER);
186}
187
188static struct irqaction timer_irq = {
189 .name = "timer",
190 .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
191 .handler = timer_interrupt,
192 .dev_id = &ckevt,
193};
194
195void __init timer_init(int irq)
196{
197 timer_config();
198
199 setup_sched_clock(mmp_read_sched_clock, 32, CLOCK_TICK_RATE);
200
201 ckevt.mult = div_sc(CLOCK_TICK_RATE, NSEC_PER_SEC, ckevt.shift);
202 ckevt.max_delta_ns = clockevent_delta2ns(MAX_DELTA, &ckevt);
203 ckevt.min_delta_ns = clockevent_delta2ns(MIN_DELTA, &ckevt);
204 ckevt.cpumask = cpumask_of(0);
205
206 setup_irq(irq, &timer_irq);
207
208 clocksource_register_hz(&cksrc, CLOCK_TICK_RATE);
209 clockevents_register_device(&ckevt);
210}
211
212#ifdef CONFIG_OF
213static struct of_device_id mmp_timer_dt_ids[] = {
214 { .compatible = "mrvl,mmp-timer", },
215 {}
216};
217
218void __init mmp_dt_init_timer(void)
219{
220 struct device_node *np;
221 int irq, ret;
222
223 np = of_find_matching_node(NULL, mmp_timer_dt_ids);
224 if (!np) {
225 ret = -ENODEV;
226 goto out;
227 }
228
229 irq = irq_of_parse_and_map(np, 0);
230 if (!irq) {
231 ret = -EINVAL;
232 goto out;
233 }
234 mmp_timer_base = of_iomap(np, 0);
235 if (!mmp_timer_base) {
236 ret = -ENOMEM;
237 goto out;
238 }
239 timer_init(irq);
240 return;
241out:
242 pr_err("Failed to get timer from device tree with error:%d\n", ret);
243}
244#endif
1/*
2 * linux/arch/arm/mach-mmp/time.c
3 *
4 * Support for clocksource and clockevents
5 *
6 * Copyright (C) 2008 Marvell International Ltd.
7 * All rights reserved.
8 *
9 * 2008-04-11: Jason Chagas <Jason.chagas@marvell.com>
10 * 2008-10-08: Bin Yang <bin.yang@marvell.com>
11 *
12 * The timers module actually includes three timers, each timer with up to
13 * three match comparators. Timer #0 is used here in free-running mode as
14 * the clock source, and match comparator #1 used as clock event device.
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License version 2 as
18 * published by the Free Software Foundation.
19 */
20
21#include <linux/init.h>
22#include <linux/kernel.h>
23#include <linux/interrupt.h>
24#include <linux/clockchips.h>
25
26#include <linux/io.h>
27#include <linux/irq.h>
28#include <linux/of.h>
29#include <linux/of_address.h>
30#include <linux/of_irq.h>
31#include <linux/sched_clock.h>
32#include <asm/mach/time.h>
33
34#include "addr-map.h"
35#include "regs-timers.h"
36#include "regs-apbc.h"
37#include "irqs.h"
38#include "cputype.h"
39#include "clock.h"
40
41#ifdef CONFIG_CPU_MMP2
42#define MMP_CLOCK_FREQ 6500000
43#else
44#define MMP_CLOCK_FREQ 3250000
45#endif
46
47#define TIMERS_VIRT_BASE TIMERS1_VIRT_BASE
48
49#define MAX_DELTA (0xfffffffe)
50#define MIN_DELTA (16)
51
52static void __iomem *mmp_timer_base = TIMERS_VIRT_BASE;
53
54/*
55 * FIXME: the timer needs some delay to stablize the counter capture
56 */
57static inline uint32_t timer_read(void)
58{
59 int delay = 100;
60
61 __raw_writel(1, mmp_timer_base + TMR_CVWR(1));
62
63 while (delay--)
64 cpu_relax();
65
66 return __raw_readl(mmp_timer_base + TMR_CVWR(1));
67}
68
69static u64 notrace mmp_read_sched_clock(void)
70{
71 return timer_read();
72}
73
74static irqreturn_t timer_interrupt(int irq, void *dev_id)
75{
76 struct clock_event_device *c = dev_id;
77
78 /*
79 * Clear pending interrupt status.
80 */
81 __raw_writel(0x01, mmp_timer_base + TMR_ICR(0));
82
83 /*
84 * Disable timer 0.
85 */
86 __raw_writel(0x02, mmp_timer_base + TMR_CER);
87
88 c->event_handler(c);
89
90 return IRQ_HANDLED;
91}
92
93static int timer_set_next_event(unsigned long delta,
94 struct clock_event_device *dev)
95{
96 unsigned long flags;
97
98 local_irq_save(flags);
99
100 /*
101 * Disable timer 0.
102 */
103 __raw_writel(0x02, mmp_timer_base + TMR_CER);
104
105 /*
106 * Clear and enable timer match 0 interrupt.
107 */
108 __raw_writel(0x01, mmp_timer_base + TMR_ICR(0));
109 __raw_writel(0x01, mmp_timer_base + TMR_IER(0));
110
111 /*
112 * Setup new clockevent timer value.
113 */
114 __raw_writel(delta - 1, mmp_timer_base + TMR_TN_MM(0, 0));
115
116 /*
117 * Enable timer 0.
118 */
119 __raw_writel(0x03, mmp_timer_base + TMR_CER);
120
121 local_irq_restore(flags);
122
123 return 0;
124}
125
126static int timer_set_shutdown(struct clock_event_device *evt)
127{
128 unsigned long flags;
129
130 local_irq_save(flags);
131 /* disable the matching interrupt */
132 __raw_writel(0x00, mmp_timer_base + TMR_IER(0));
133 local_irq_restore(flags);
134
135 return 0;
136}
137
138static struct clock_event_device ckevt = {
139 .name = "clockevent",
140 .features = CLOCK_EVT_FEAT_ONESHOT,
141 .rating = 200,
142 .set_next_event = timer_set_next_event,
143 .set_state_shutdown = timer_set_shutdown,
144 .set_state_oneshot = timer_set_shutdown,
145};
146
147static u64 clksrc_read(struct clocksource *cs)
148{
149 return timer_read();
150}
151
152static struct clocksource cksrc = {
153 .name = "clocksource",
154 .rating = 200,
155 .read = clksrc_read,
156 .mask = CLOCKSOURCE_MASK(32),
157 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
158};
159
160static void __init timer_config(void)
161{
162 uint32_t ccr = __raw_readl(mmp_timer_base + TMR_CCR);
163
164 __raw_writel(0x0, mmp_timer_base + TMR_CER); /* disable */
165
166 ccr &= (cpu_is_mmp2()) ? (TMR_CCR_CS_0(0) | TMR_CCR_CS_1(0)) :
167 (TMR_CCR_CS_0(3) | TMR_CCR_CS_1(3));
168 __raw_writel(ccr, mmp_timer_base + TMR_CCR);
169
170 /* set timer 0 to periodic mode, and timer 1 to free-running mode */
171 __raw_writel(0x2, mmp_timer_base + TMR_CMR);
172
173 __raw_writel(0x1, mmp_timer_base + TMR_PLCR(0)); /* periodic */
174 __raw_writel(0x7, mmp_timer_base + TMR_ICR(0)); /* clear status */
175 __raw_writel(0x0, mmp_timer_base + TMR_IER(0));
176
177 __raw_writel(0x0, mmp_timer_base + TMR_PLCR(1)); /* free-running */
178 __raw_writel(0x7, mmp_timer_base + TMR_ICR(1)); /* clear status */
179 __raw_writel(0x0, mmp_timer_base + TMR_IER(1));
180
181 /* enable timer 1 counter */
182 __raw_writel(0x2, mmp_timer_base + TMR_CER);
183}
184
185static struct irqaction timer_irq = {
186 .name = "timer",
187 .flags = IRQF_TIMER | IRQF_IRQPOLL,
188 .handler = timer_interrupt,
189 .dev_id = &ckevt,
190};
191
192void __init timer_init(int irq)
193{
194 timer_config();
195
196 sched_clock_register(mmp_read_sched_clock, 32, MMP_CLOCK_FREQ);
197
198 ckevt.cpumask = cpumask_of(0);
199
200 setup_irq(irq, &timer_irq);
201
202 clocksource_register_hz(&cksrc, MMP_CLOCK_FREQ);
203 clockevents_config_and_register(&ckevt, MMP_CLOCK_FREQ,
204 MIN_DELTA, MAX_DELTA);
205}
206
207#ifdef CONFIG_OF
208static const struct of_device_id mmp_timer_dt_ids[] = {
209 { .compatible = "mrvl,mmp-timer", },
210 {}
211};
212
213void __init mmp_dt_init_timer(void)
214{
215 struct device_node *np;
216 int irq, ret;
217
218 np = of_find_matching_node(NULL, mmp_timer_dt_ids);
219 if (!np) {
220 ret = -ENODEV;
221 goto out;
222 }
223
224 irq = irq_of_parse_and_map(np, 0);
225 if (!irq) {
226 ret = -EINVAL;
227 goto out;
228 }
229 mmp_timer_base = of_iomap(np, 0);
230 if (!mmp_timer_base) {
231 ret = -ENOMEM;
232 goto out;
233 }
234 timer_init(irq);
235 return;
236out:
237 pr_err("Failed to get timer from device tree with error:%d\n", ret);
238}
239#endif