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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/mach-mmp/time.c
4 *
5 * Support for clocksource and clockevents
6 *
7 * Copyright (C) 2008 Marvell International Ltd.
8 * All rights reserved.
9 *
10 * 2008-04-11: Jason Chagas <Jason.chagas@marvell.com>
11 * 2008-10-08: Bin Yang <bin.yang@marvell.com>
12 *
13 * The timers module actually includes three timers, each timer with up to
14 * three match comparators. Timer #0 is used here in free-running mode as
15 * the clock source, and match comparator #1 used as clock event device.
16 */
17
18#include <linux/init.h>
19#include <linux/kernel.h>
20#include <linux/interrupt.h>
21#include <linux/clockchips.h>
22#include <linux/clk.h>
23
24#include <linux/io.h>
25#include <linux/irq.h>
26#include <linux/of.h>
27#include <linux/of_address.h>
28#include <linux/of_irq.h>
29#include <linux/sched_clock.h>
30#include <asm/mach/time.h>
31
32#include "regs-timers.h"
33#include <linux/soc/mmp/cputype.h>
34
35#define MAX_DELTA (0xfffffffe)
36#define MIN_DELTA (16)
37
38static void __iomem *mmp_timer_base;
39
40/*
41 * Read the timer through the CVWR register. Delay is required after requesting
42 * a read. The CR register cannot be directly read due to metastability issues
43 * documented in the PXA168 software manual.
44 */
45static inline uint32_t timer_read(void)
46{
47 uint32_t val;
48 int delay = 3;
49
50 __raw_writel(1, mmp_timer_base + TMR_CVWR(1));
51
52 while (delay--)
53 val = __raw_readl(mmp_timer_base + TMR_CVWR(1));
54
55 return val;
56}
57
58static u64 notrace mmp_read_sched_clock(void)
59{
60 return timer_read();
61}
62
63static irqreturn_t timer_interrupt(int irq, void *dev_id)
64{
65 struct clock_event_device *c = dev_id;
66
67 /*
68 * Clear pending interrupt status.
69 */
70 __raw_writel(0x01, mmp_timer_base + TMR_ICR(0));
71
72 /*
73 * Disable timer 0.
74 */
75 __raw_writel(0x02, mmp_timer_base + TMR_CER);
76
77 c->event_handler(c);
78
79 return IRQ_HANDLED;
80}
81
82static int timer_set_next_event(unsigned long delta,
83 struct clock_event_device *dev)
84{
85 unsigned long flags;
86
87 local_irq_save(flags);
88
89 /*
90 * Disable timer 0.
91 */
92 __raw_writel(0x02, mmp_timer_base + TMR_CER);
93
94 /*
95 * Clear and enable timer match 0 interrupt.
96 */
97 __raw_writel(0x01, mmp_timer_base + TMR_ICR(0));
98 __raw_writel(0x01, mmp_timer_base + TMR_IER(0));
99
100 /*
101 * Setup new clockevent timer value.
102 */
103 __raw_writel(delta - 1, mmp_timer_base + TMR_TN_MM(0, 0));
104
105 /*
106 * Enable timer 0.
107 */
108 __raw_writel(0x03, mmp_timer_base + TMR_CER);
109
110 local_irq_restore(flags);
111
112 return 0;
113}
114
115static int timer_set_shutdown(struct clock_event_device *evt)
116{
117 unsigned long flags;
118
119 local_irq_save(flags);
120 /* disable the matching interrupt */
121 __raw_writel(0x00, mmp_timer_base + TMR_IER(0));
122 local_irq_restore(flags);
123
124 return 0;
125}
126
127static struct clock_event_device ckevt = {
128 .name = "clockevent",
129 .features = CLOCK_EVT_FEAT_ONESHOT,
130 .rating = 200,
131 .set_next_event = timer_set_next_event,
132 .set_state_shutdown = timer_set_shutdown,
133 .set_state_oneshot = timer_set_shutdown,
134};
135
136static u64 clksrc_read(struct clocksource *cs)
137{
138 return timer_read();
139}
140
141static struct clocksource cksrc = {
142 .name = "clocksource",
143 .rating = 200,
144 .read = clksrc_read,
145 .mask = CLOCKSOURCE_MASK(32),
146 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
147};
148
149static void __init timer_config(void)
150{
151 uint32_t ccr = __raw_readl(mmp_timer_base + TMR_CCR);
152
153 __raw_writel(0x0, mmp_timer_base + TMR_CER); /* disable */
154
155 ccr &= (cpu_is_mmp2() || cpu_is_mmp3()) ?
156 (TMR_CCR_CS_0(0) | TMR_CCR_CS_1(0)) :
157 (TMR_CCR_CS_0(3) | TMR_CCR_CS_1(3));
158 __raw_writel(ccr, mmp_timer_base + TMR_CCR);
159
160 /* set timer 0 to periodic mode, and timer 1 to free-running mode */
161 __raw_writel(0x2, mmp_timer_base + TMR_CMR);
162
163 __raw_writel(0x1, mmp_timer_base + TMR_PLCR(0)); /* periodic */
164 __raw_writel(0x7, mmp_timer_base + TMR_ICR(0)); /* clear status */
165 __raw_writel(0x0, mmp_timer_base + TMR_IER(0));
166
167 __raw_writel(0x0, mmp_timer_base + TMR_PLCR(1)); /* free-running */
168 __raw_writel(0x7, mmp_timer_base + TMR_ICR(1)); /* clear status */
169 __raw_writel(0x0, mmp_timer_base + TMR_IER(1));
170
171 /* enable timer 1 counter */
172 __raw_writel(0x2, mmp_timer_base + TMR_CER);
173}
174
175static void __init mmp_timer_init(int irq, unsigned long rate)
176{
177 timer_config();
178
179 sched_clock_register(mmp_read_sched_clock, 32, rate);
180
181 ckevt.cpumask = cpumask_of(0);
182
183 if (request_irq(irq, timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
184 "timer", &ckevt))
185 pr_err("Failed to request irq %d (timer)\n", irq);
186
187 clocksource_register_hz(&cksrc, rate);
188 clockevents_config_and_register(&ckevt, rate, MIN_DELTA, MAX_DELTA);
189}
190
191static int __init mmp_dt_init_timer(struct device_node *np)
192{
193 struct clk *clk;
194 int irq, ret;
195 unsigned long rate;
196
197 clk = of_clk_get(np, 0);
198 if (!IS_ERR(clk)) {
199 ret = clk_prepare_enable(clk);
200 if (ret)
201 return ret;
202 rate = clk_get_rate(clk);
203 } else if (cpu_is_pj4()) {
204 rate = 6500000;
205 } else {
206 rate = 3250000;
207 }
208
209 irq = irq_of_parse_and_map(np, 0);
210 if (!irq)
211 return -EINVAL;
212
213 mmp_timer_base = of_iomap(np, 0);
214 if (!mmp_timer_base)
215 return -ENOMEM;
216
217 mmp_timer_init(irq, rate);
218 return 0;
219}
220
221TIMER_OF_DECLARE(mmp_timer, "mrvl,mmp-timer", mmp_dt_init_timer);
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