blob: 9facf04bd3e9ea22c658834791838870e540be71 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2011 Antony Pavlov <antonynpavlov@gmail.com>
*/
/**
* @file
* @brief Clocksource based on MIPS CP0 timer
*/
#include <init.h>
#include <of.h>
#include <linux/clk.h>
#include <clock.h>
#include <io.h>
#include <asm/mipsregs.h>
static uint64_t c0_hpt_read(void)
{
return read_c0_count();
}
static struct clocksource cs = {
.read = c0_hpt_read,
.mask = CLOCKSOURCE_MASK(32),
};
static int clocksource_init(void)
{
unsigned int mips_hpt_frequency;
struct device_node *np;
struct clk *clk;
/* default rate: 100 MHz */
mips_hpt_frequency = 100000000;
if (IS_ENABLED(CONFIG_OFTREE)) {
np = of_get_cpu_node(0, NULL);
if (np) {
clk = of_clk_get(np, 0);
if (!IS_ERR(clk)) {
mips_hpt_frequency = clk_get_rate(clk) / 2;
}
}
}
clocks_calc_mult_shift(&cs.mult, &cs.shift,
mips_hpt_frequency, NSEC_PER_SEC, 10);
return init_clock(&cs);
}
postcore_initcall(clocksource_init);
|