2
* This program is free software; you can redistribute it and/or modify it
3
* under the terms of the GNU General Public License version 2 as published
4
* by the Free Software Foundation.
6
* Copyright (C) 2010 Thomas Langer <thomas.langer@lantiq.com>
7
* Copyright (C) 2010 John Crispin <blogic@openwrt.org>
10
#include <linux/module.h>
11
#include <linux/init.h>
12
#include <linux/kernel.h>
13
#include <linux/types.h>
14
#include <linux/clk.h>
15
#include <linux/err.h>
16
#include <linux/list.h>
20
#include <asm/div64.h>
22
#include <lantiq_soc.h>
29
unsigned long (*get_rate) (void);
32
static struct clk *cpu_clk;
33
static int cpu_clk_cnt;
35
/* lantiq socs have 3 static clocks */
36
static struct clk cpu_clk_generic[] = {
39
.get_rate = ltq_get_cpu_hz,
42
.get_rate = ltq_get_fpi_hz,
45
.get_rate = ltq_get_io_region_clock,
49
static struct resource ltq_cgu_resource = {
51
.start = LTQ_CGU_BASE_ADDR,
52
.end = LTQ_CGU_BASE_ADDR + LTQ_CGU_SIZE - 1,
53
.flags = IORESOURCE_MEM,
56
/* remapped clock register range */
57
void __iomem *ltq_cgu_membase;
61
cpu_clk = cpu_clk_generic;
62
cpu_clk_cnt = ARRAY_SIZE(cpu_clk_generic);
65
static inline int clk_good(struct clk *clk)
67
return clk && !IS_ERR(clk);
70
unsigned long clk_get_rate(struct clk *clk)
72
if (unlikely(!clk_good(clk)))
78
if (clk->get_rate != NULL)
79
return clk->get_rate();
83
EXPORT_SYMBOL(clk_get_rate);
85
struct clk *clk_get(struct device *dev, const char *id)
89
for (i = 0; i < cpu_clk_cnt; i++)
90
if (!strcmp(id, cpu_clk[i].name))
93
return ERR_PTR(-ENOENT);
95
EXPORT_SYMBOL(clk_get);
97
void clk_put(struct clk *clk)
101
EXPORT_SYMBOL(clk_put);
103
static inline u32 ltq_get_counter_resolution(void)
107
__asm__ __volatile__(
119
void __init plat_time_init(void)
123
if (insert_resource(&iomem_resource, <q_cgu_resource) < 0)
124
panic("Failed to insert cgu memory\n");
126
if (request_mem_region(ltq_cgu_resource.start,
127
resource_size(<q_cgu_resource), "cgu") < 0)
128
panic("Failed to request cgu memory\n");
130
ltq_cgu_membase = ioremap_nocache(ltq_cgu_resource.start,
131
resource_size(<q_cgu_resource));
132
if (!ltq_cgu_membase) {
133
pr_err("Failed to remap cgu memory\n");
136
clk = clk_get(0, "cpu");
137
mips_hpt_frequency = clk_get_rate(clk) / ltq_get_counter_resolution();
138
write_c0_compare(read_c0_count());