1
2
3
4
5
6
7
8
9
10
11
12
13
14#include <linux/kernel.h>
15#include <linux/bitops.h>
16#include <linux/clk.h>
17#include <linux/clockchips.h>
18#include <linux/delay.h>
19#include <linux/interrupt.h>
20#include <linux/of_address.h>
21#include <linux/of_irq.h>
22#include <linux/spinlock.h>
23#include <linux/sched_clock.h>
24
25#define TIMER_CTRL 0x00
26#define TIMER0_EN BIT(0)
27#define TIMER0_RELOAD_EN BIT(1)
28#define TIMER1_EN BIT(2)
29#define TIMER1_RELOAD_EN BIT(3)
30#define TIMER0_RELOAD 0x10
31#define TIMER0_VAL 0x14
32#define TIMER1_RELOAD 0x18
33#define TIMER1_VAL 0x1c
34
35#define ORION_ONESHOT_MIN 1
36#define ORION_ONESHOT_MAX 0xfffffffe
37
38static void __iomem *timer_base;
39
40static unsigned long notrace orion_read_timer(void)
41{
42 return ~readl(timer_base + TIMER0_VAL);
43}
44
45static struct delay_timer orion_delay_timer = {
46 .read_current_timer = orion_read_timer,
47};
48
49static void orion_delay_timer_init(unsigned long rate)
50{
51 orion_delay_timer.freq = rate;
52 register_current_timer_delay(&orion_delay_timer);
53}
54
55
56
57
58static u64 notrace orion_read_sched_clock(void)
59{
60 return ~readl(timer_base + TIMER0_VAL);
61}
62
63
64
65
66static u32 ticks_per_jiffy;
67
68static int orion_clkevt_next_event(unsigned long delta,
69 struct clock_event_device *dev)
70{
71
72 writel(delta, timer_base + TIMER1_VAL);
73 atomic_io_modify(timer_base + TIMER_CTRL,
74 TIMER1_RELOAD_EN | TIMER1_EN, TIMER1_EN);
75
76 return 0;
77}
78
79static int orion_clkevt_shutdown(struct clock_event_device *dev)
80{
81
82 atomic_io_modify(timer_base + TIMER_CTRL,
83 TIMER1_RELOAD_EN | TIMER1_EN, 0);
84 return 0;
85}
86
87static int orion_clkevt_set_periodic(struct clock_event_device *dev)
88{
89
90 writel(ticks_per_jiffy - 1, timer_base + TIMER1_RELOAD);
91 writel(ticks_per_jiffy - 1, timer_base + TIMER1_VAL);
92 atomic_io_modify(timer_base + TIMER_CTRL,
93 TIMER1_RELOAD_EN | TIMER1_EN,
94 TIMER1_RELOAD_EN | TIMER1_EN);
95 return 0;
96}
97
98static struct clock_event_device orion_clkevt = {
99 .name = "orion_event",
100 .features = CLOCK_EVT_FEAT_ONESHOT |
101 CLOCK_EVT_FEAT_PERIODIC,
102 .shift = 32,
103 .rating = 300,
104 .set_next_event = orion_clkevt_next_event,
105 .set_state_shutdown = orion_clkevt_shutdown,
106 .set_state_periodic = orion_clkevt_set_periodic,
107 .set_state_oneshot = orion_clkevt_shutdown,
108 .tick_resume = orion_clkevt_shutdown,
109};
110
111static irqreturn_t orion_clkevt_irq_handler(int irq, void *dev_id)
112{
113 orion_clkevt.event_handler(&orion_clkevt);
114 return IRQ_HANDLED;
115}
116
117static int __init orion_timer_init(struct device_node *np)
118{
119 unsigned long rate;
120 struct clk *clk;
121 int irq, ret;
122
123
124 timer_base = of_iomap(np, 0);
125 if (!timer_base) {
126 pr_err("%pOFn: unable to map resource\n", np);
127 return -ENXIO;
128 }
129
130 clk = of_clk_get(np, 0);
131 if (IS_ERR(clk)) {
132 pr_err("%pOFn: unable to get clk\n", np);
133 return PTR_ERR(clk);
134 }
135
136 ret = clk_prepare_enable(clk);
137 if (ret) {
138 pr_err("Failed to prepare clock\n");
139 return ret;
140 }
141
142
143 irq = irq_of_parse_and_map(np, 1);
144 if (irq <= 0) {
145 pr_err("%pOFn: unable to parse timer1 irq\n", np);
146 ret = -EINVAL;
147 goto out_unprep_clk;
148 }
149
150 rate = clk_get_rate(clk);
151
152
153 writel(~0, timer_base + TIMER0_VAL);
154 writel(~0, timer_base + TIMER0_RELOAD);
155 atomic_io_modify(timer_base + TIMER_CTRL,
156 TIMER0_RELOAD_EN | TIMER0_EN,
157 TIMER0_RELOAD_EN | TIMER0_EN);
158
159 ret = clocksource_mmio_init(timer_base + TIMER0_VAL,
160 "orion_clocksource", rate, 300, 32,
161 clocksource_mmio_readl_down);
162 if (ret) {
163 pr_err("Failed to initialize mmio timer\n");
164 goto out_unprep_clk;
165 }
166
167 sched_clock_register(orion_read_sched_clock, 32, rate);
168
169
170 ret = request_irq(irq, orion_clkevt_irq_handler, IRQF_TIMER,
171 "orion_event", NULL);
172 if (ret) {
173 pr_err("%pOFn: unable to setup irq\n", np);
174 goto out_unprep_clk;
175 }
176
177 ticks_per_jiffy = (clk_get_rate(clk) + HZ/2) / HZ;
178 orion_clkevt.cpumask = cpumask_of(0);
179 orion_clkevt.irq = irq;
180 clockevents_config_and_register(&orion_clkevt, rate,
181 ORION_ONESHOT_MIN, ORION_ONESHOT_MAX);
182
183
184 orion_delay_timer_init(rate);
185
186 return 0;
187
188out_unprep_clk:
189 clk_disable_unprepare(clk);
190 return ret;
191}
192TIMER_OF_DECLARE(orion_timer, "marvell,orion-timer", orion_timer_init);
193
