Commit | Line | Data |
---|---|---|
ccd63ce4 MG |
1 | #include <linux/clocksource.h> |
2 | #include <linux/sched_clock.h> | |
3 | #include <linux/of_address.h> | |
4 | #include <linux/printk.h> | |
5 | #include <linux/delay.h> | |
6 | #include <linux/init.h> | |
7 | #include <linux/clk.h> | |
8 | ||
9 | static void __iomem *xtal_in_cnt; | |
10 | static struct delay_timer delay_timer; | |
11 | ||
12 | static unsigned long notrace read_xtal_counter(void) | |
13 | { | |
14 | return readl_relaxed(xtal_in_cnt); | |
15 | } | |
16 | ||
17 | static u64 notrace read_sched_clock(void) | |
18 | { | |
19 | return read_xtal_counter(); | |
20 | } | |
21 | ||
22 | static cycle_t read_clocksource(struct clocksource *cs) | |
23 | { | |
24 | return read_xtal_counter(); | |
25 | } | |
26 | ||
27 | static struct clocksource tango_xtal = { | |
28 | .name = "tango-xtal", | |
29 | .rating = 350, | |
30 | .read = read_clocksource, | |
31 | .mask = CLOCKSOURCE_MASK(32), | |
32 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
33 | }; | |
34 | ||
35 | static void __init tango_clocksource_init(struct device_node *np) | |
36 | { | |
37 | struct clk *clk; | |
38 | int xtal_freq, ret; | |
39 | ||
40 | xtal_in_cnt = of_iomap(np, 0); | |
41 | if (xtal_in_cnt == NULL) { | |
42 | pr_err("%s: invalid address\n", np->full_name); | |
43 | return; | |
44 | } | |
45 | ||
46 | clk = of_clk_get(np, 0); | |
47 | if (IS_ERR(clk)) { | |
48 | pr_err("%s: invalid clock\n", np->full_name); | |
49 | return; | |
50 | } | |
51 | ||
52 | xtal_freq = clk_get_rate(clk); | |
53 | delay_timer.freq = xtal_freq; | |
54 | delay_timer.read_current_timer = read_xtal_counter; | |
55 | ||
56 | ret = clocksource_register_hz(&tango_xtal, xtal_freq); | |
57 | if (ret != 0) { | |
58 | pr_err("%s: registration failed\n", np->full_name); | |
59 | return; | |
60 | } | |
61 | ||
62 | sched_clock_register(read_sched_clock, 32, xtal_freq); | |
63 | register_current_timer_delay(&delay_timer); | |
64 | } | |
65 | ||
66 | CLOCKSOURCE_OF_DECLARE(tango, "sigma,tick-counter", tango_clocksource_init); |