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 int clk_enable(struct clk *clk)
108 EXPORT_SYMBOL(clk_enable);
110 void clk_disable(struct clk *clk)
114 EXPORT_SYMBOL(clk_disable);
116 static inline u32 ltq_get_counter_resolution(void)
120 __asm__ __volatile__(
132 void __init plat_time_init(void)
136 if (insert_resource(&iomem_resource, <q_cgu_resource) < 0)
137 panic("Failed to insert cgu memory\n");
139 if (request_mem_region(ltq_cgu_resource.start,
140 resource_size(<q_cgu_resource), "cgu") < 0)
141 panic("Failed to request cgu memory\n");
143 ltq_cgu_membase = ioremap_nocache(ltq_cgu_resource.start,
144 resource_size(<q_cgu_resource));
145 if (!ltq_cgu_membase) {
146 pr_err("Failed to remap cgu memory\n");
149 clk = clk_get(0, "cpu");
150 mips_hpt_frequency = clk_get_rate(clk) / ltq_get_counter_resolution();
151 write_c0_compare(read_c0_count());