diff options
Diffstat (limited to 'arch/mips/loongson1/common/clock.c')
-rw-r--r-- | arch/mips/loongson1/common/clock.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/arch/mips/loongson1/common/clock.c b/arch/mips/loongson1/common/clock.c new file mode 100644 index 000000000000..2d98fb030596 --- /dev/null +++ b/arch/mips/loongson1/common/clock.c | |||
@@ -0,0 +1,165 @@ | |||
1 | /* | ||
2 | * Copyright (c) 2011 Zhang, Keguang <keguang.zhang@gmail.com> | ||
3 | * | ||
4 | * This program is free software; you can redistribute it and/or modify it | ||
5 | * under the terms of the GNU General Public License as published by the | ||
6 | * Free Software Foundation; either version 2 of the License, or (at your | ||
7 | * option) any later version. | ||
8 | */ | ||
9 | |||
10 | #include <linux/module.h> | ||
11 | #include <linux/list.h> | ||
12 | #include <linux/mutex.h> | ||
13 | #include <linux/clk.h> | ||
14 | #include <linux/err.h> | ||
15 | #include <asm/clock.h> | ||
16 | #include <asm/time.h> | ||
17 | |||
18 | #include <loongson1.h> | ||
19 | |||
20 | static LIST_HEAD(clocks); | ||
21 | static DEFINE_MUTEX(clocks_mutex); | ||
22 | |||
23 | struct clk *clk_get(struct device *dev, const char *name) | ||
24 | { | ||
25 | struct clk *c; | ||
26 | struct clk *ret = NULL; | ||
27 | |||
28 | mutex_lock(&clocks_mutex); | ||
29 | list_for_each_entry(c, &clocks, node) { | ||
30 | if (!strcmp(c->name, name)) { | ||
31 | ret = c; | ||
32 | break; | ||
33 | } | ||
34 | } | ||
35 | mutex_unlock(&clocks_mutex); | ||
36 | |||
37 | return ret; | ||
38 | } | ||
39 | EXPORT_SYMBOL(clk_get); | ||
40 | |||
41 | unsigned long clk_get_rate(struct clk *clk) | ||
42 | { | ||
43 | return clk->rate; | ||
44 | } | ||
45 | EXPORT_SYMBOL(clk_get_rate); | ||
46 | |||
47 | static void pll_clk_init(struct clk *clk) | ||
48 | { | ||
49 | u32 pll; | ||
50 | |||
51 | pll = __raw_readl(LS1X_CLK_PLL_FREQ); | ||
52 | clk->rate = (12 + (pll & 0x3f)) * 33 / 2 | ||
53 | + ((pll >> 8) & 0x3ff) * 33 / 1024 / 2; | ||
54 | clk->rate *= 1000000; | ||
55 | } | ||
56 | |||
57 | static void cpu_clk_init(struct clk *clk) | ||
58 | { | ||
59 | u32 pll, ctrl; | ||
60 | |||
61 | pll = clk_get_rate(clk->parent); | ||
62 | ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_CPU; | ||
63 | clk->rate = pll / (ctrl >> DIV_CPU_SHIFT); | ||
64 | } | ||
65 | |||
66 | static void ddr_clk_init(struct clk *clk) | ||
67 | { | ||
68 | u32 pll, ctrl; | ||
69 | |||
70 | pll = clk_get_rate(clk->parent); | ||
71 | ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_DDR; | ||
72 | clk->rate = pll / (ctrl >> DIV_DDR_SHIFT); | ||
73 | } | ||
74 | |||
75 | static void dc_clk_init(struct clk *clk) | ||
76 | { | ||
77 | u32 pll, ctrl; | ||
78 | |||
79 | pll = clk_get_rate(clk->parent); | ||
80 | ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_DC; | ||
81 | clk->rate = pll / (ctrl >> DIV_DC_SHIFT); | ||
82 | } | ||
83 | |||
84 | static struct clk_ops pll_clk_ops = { | ||
85 | .init = pll_clk_init, | ||
86 | }; | ||
87 | |||
88 | static struct clk_ops cpu_clk_ops = { | ||
89 | .init = cpu_clk_init, | ||
90 | }; | ||
91 | |||
92 | static struct clk_ops ddr_clk_ops = { | ||
93 | .init = ddr_clk_init, | ||
94 | }; | ||
95 | |||
96 | static struct clk_ops dc_clk_ops = { | ||
97 | .init = dc_clk_init, | ||
98 | }; | ||
99 | |||
100 | static struct clk pll_clk = { | ||
101 | .name = "pll", | ||
102 | .ops = &pll_clk_ops, | ||
103 | }; | ||
104 | |||
105 | static struct clk cpu_clk = { | ||
106 | .name = "cpu", | ||
107 | .parent = &pll_clk, | ||
108 | .ops = &cpu_clk_ops, | ||
109 | }; | ||
110 | |||
111 | static struct clk ddr_clk = { | ||
112 | .name = "ddr", | ||
113 | .parent = &pll_clk, | ||
114 | .ops = &ddr_clk_ops, | ||
115 | }; | ||
116 | |||
117 | static struct clk dc_clk = { | ||
118 | .name = "dc", | ||
119 | .parent = &pll_clk, | ||
120 | .ops = &dc_clk_ops, | ||
121 | }; | ||
122 | |||
123 | int clk_register(struct clk *clk) | ||
124 | { | ||
125 | mutex_lock(&clocks_mutex); | ||
126 | list_add(&clk->node, &clocks); | ||
127 | if (clk->ops->init) | ||
128 | clk->ops->init(clk); | ||
129 | mutex_unlock(&clocks_mutex); | ||
130 | |||
131 | return 0; | ||
132 | } | ||
133 | EXPORT_SYMBOL(clk_register); | ||
134 | |||
135 | static struct clk *ls1x_clks[] = { | ||
136 | &pll_clk, | ||
137 | &cpu_clk, | ||
138 | &ddr_clk, | ||
139 | &dc_clk, | ||
140 | }; | ||
141 | |||
142 | int __init ls1x_clock_init(void) | ||
143 | { | ||
144 | int i; | ||
145 | |||
146 | for (i = 0; i < ARRAY_SIZE(ls1x_clks); i++) | ||
147 | clk_register(ls1x_clks[i]); | ||
148 | |||
149 | return 0; | ||
150 | } | ||
151 | |||
152 | void __init plat_time_init(void) | ||
153 | { | ||
154 | struct clk *clk; | ||
155 | |||
156 | /* Initialize LS1X clocks */ | ||
157 | ls1x_clock_init(); | ||
158 | |||
159 | /* setup mips r4k timer */ | ||
160 | clk = clk_get(NULL, "cpu"); | ||
161 | if (IS_ERR(clk)) | ||
162 | panic("unable to get dc clock, err=%ld", PTR_ERR(clk)); | ||
163 | |||
164 | mips_hpt_frequency = clk_get_rate(clk) / 2; | ||
165 | } | ||