diff options
author | David Woodhouse <David.Woodhouse@intel.com> | 2008-07-25 10:40:14 -0400 |
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committer | David Woodhouse <David.Woodhouse@intel.com> | 2008-07-25 10:40:14 -0400 |
commit | ff877ea80efa2015b6263766f78ee42c2a1b32f9 (patch) | |
tree | 85205005c611ab774702148558321c6fb92f1ccd /arch/arm/mach-imx/clock.c | |
parent | 30821fee4f0cb3e6d241d9f7ddc37742212e3eb7 (diff) | |
parent | d37e6bf68fc1eb34a4ad21d9ae8890ed37ea80e7 (diff) |
Merge branch 'linux-next' of git://git.infradead.org/~dedekind/ubi-2.6
Diffstat (limited to 'arch/arm/mach-imx/clock.c')
-rw-r--r-- | arch/arm/mach-imx/clock.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/clock.c b/arch/arm/mach-imx/clock.c new file mode 100644 index 000000000000..6a90fe5578df --- /dev/null +++ b/arch/arm/mach-imx/clock.c | |||
@@ -0,0 +1,205 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2008 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix | ||
3 | * | ||
4 | * This program is free software; you can redistribute it and/or modify | ||
5 | * it under the terms of the GNU General Public License as published by | ||
6 | * the Free Software Foundation; either version 2 of the License, or | ||
7 | * (at your option) any later version. | ||
8 | * | ||
9 | * This program is distributed in the hope that it will be useful, | ||
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
12 | * GNU General Public License for more details. | ||
13 | * | ||
14 | * You should have received a copy of the GNU General Public License | ||
15 | * along with this program; if not, write to the Free Software | ||
16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||
17 | */ | ||
18 | |||
19 | #include <linux/kernel.h> | ||
20 | #include <linux/device.h> | ||
21 | #include <linux/list.h> | ||
22 | #include <linux/math64.h> | ||
23 | #include <linux/err.h> | ||
24 | |||
25 | #include <asm/io.h> | ||
26 | #include <asm/arch/imx-regs.h> | ||
27 | |||
28 | /* | ||
29 | * Very simple approach: We can't disable clocks, so we do | ||
30 | * not need refcounting | ||
31 | */ | ||
32 | |||
33 | struct clk { | ||
34 | struct list_head node; | ||
35 | const char *name; | ||
36 | unsigned long (*get_rate)(void); | ||
37 | }; | ||
38 | |||
39 | /* | ||
40 | * get the system pll clock in Hz | ||
41 | * | ||
42 | * mfi + mfn / (mfd +1) | ||
43 | * f = 2 * f_ref * -------------------- | ||
44 | * pd + 1 | ||
45 | */ | ||
46 | static unsigned long imx_decode_pll(unsigned int pll, u32 f_ref) | ||
47 | { | ||
48 | unsigned long long ll; | ||
49 | unsigned long quot; | ||
50 | |||
51 | u32 mfi = (pll >> 10) & 0xf; | ||
52 | u32 mfn = pll & 0x3ff; | ||
53 | u32 mfd = (pll >> 16) & 0x3ff; | ||
54 | u32 pd = (pll >> 26) & 0xf; | ||
55 | |||
56 | mfi = mfi <= 5 ? 5 : mfi; | ||
57 | |||
58 | ll = 2 * (unsigned long long)f_ref * | ||
59 | ((mfi << 16) + (mfn << 16) / (mfd + 1)); | ||
60 | quot = (pd + 1) * (1 << 16); | ||
61 | ll += quot / 2; | ||
62 | do_div(ll, quot); | ||
63 | return (unsigned long)ll; | ||
64 | } | ||
65 | |||
66 | static unsigned long imx_get_system_clk(void) | ||
67 | { | ||
68 | u32 f_ref = (CSCR & CSCR_SYSTEM_SEL) ? 16000000 : (CLK32 * 512); | ||
69 | |||
70 | return imx_decode_pll(SPCTL0, f_ref); | ||
71 | } | ||
72 | |||
73 | static unsigned long imx_get_mcu_clk(void) | ||
74 | { | ||
75 | return imx_decode_pll(MPCTL0, CLK32 * 512); | ||
76 | } | ||
77 | |||
78 | /* | ||
79 | * get peripheral clock 1 ( UART[12], Timer[12], PWM ) | ||
80 | */ | ||
81 | static unsigned long imx_get_perclk1(void) | ||
82 | { | ||
83 | return imx_get_system_clk() / (((PCDR) & 0xf)+1); | ||
84 | } | ||
85 | |||
86 | /* | ||
87 | * get peripheral clock 2 ( LCD, SD, SPI[12] ) | ||
88 | */ | ||
89 | static unsigned long imx_get_perclk2(void) | ||
90 | { | ||
91 | return imx_get_system_clk() / (((PCDR>>4) & 0xf)+1); | ||
92 | } | ||
93 | |||
94 | /* | ||
95 | * get peripheral clock 3 ( SSI ) | ||
96 | */ | ||
97 | static unsigned long imx_get_perclk3(void) | ||
98 | { | ||
99 | return imx_get_system_clk() / (((PCDR>>16) & 0x7f)+1); | ||
100 | } | ||
101 | |||
102 | /* | ||
103 | * get hclk ( SDRAM, CSI, Memory Stick, I2C, DMA ) | ||
104 | */ | ||
105 | static unsigned long imx_get_hclk(void) | ||
106 | { | ||
107 | return imx_get_system_clk() / (((CSCR>>10) & 0xf)+1); | ||
108 | } | ||
109 | |||
110 | static struct clk clk_system_clk = { | ||
111 | .name = "system_clk", | ||
112 | .get_rate = imx_get_system_clk, | ||
113 | }; | ||
114 | |||
115 | static struct clk clk_hclk = { | ||
116 | .name = "hclk", | ||
117 | .get_rate = imx_get_hclk, | ||
118 | }; | ||
119 | |||
120 | static struct clk clk_mcu_clk = { | ||
121 | .name = "mcu_clk", | ||
122 | .get_rate = imx_get_mcu_clk, | ||
123 | }; | ||
124 | |||
125 | static struct clk clk_perclk1 = { | ||
126 | .name = "perclk1", | ||
127 | .get_rate = imx_get_perclk1, | ||
128 | }; | ||
129 | |||
130 | static struct clk clk_uart_clk = { | ||
131 | .name = "uart_clk", | ||
132 | .get_rate = imx_get_perclk1, | ||
133 | }; | ||
134 | |||
135 | static struct clk clk_perclk2 = { | ||
136 | .name = "perclk2", | ||
137 | .get_rate = imx_get_perclk2, | ||
138 | }; | ||
139 | |||
140 | static struct clk clk_perclk3 = { | ||
141 | .name = "perclk3", | ||
142 | .get_rate = imx_get_perclk3, | ||
143 | }; | ||
144 | |||
145 | static struct clk *clks[] = { | ||
146 | &clk_perclk1, | ||
147 | &clk_perclk2, | ||
148 | &clk_perclk3, | ||
149 | &clk_system_clk, | ||
150 | &clk_hclk, | ||
151 | &clk_mcu_clk, | ||
152 | &clk_uart_clk, | ||
153 | }; | ||
154 | |||
155 | static LIST_HEAD(clocks); | ||
156 | static DEFINE_MUTEX(clocks_mutex); | ||
157 | |||
158 | struct clk *clk_get(struct device *dev, const char *id) | ||
159 | { | ||
160 | struct clk *p, *clk = ERR_PTR(-ENOENT); | ||
161 | |||
162 | mutex_lock(&clocks_mutex); | ||
163 | list_for_each_entry(p, &clocks, node) { | ||
164 | if (!strcmp(p->name, id)) { | ||
165 | clk = p; | ||
166 | goto found; | ||
167 | } | ||
168 | } | ||
169 | |||
170 | found: | ||
171 | mutex_unlock(&clocks_mutex); | ||
172 | |||
173 | return clk; | ||
174 | } | ||
175 | |||
176 | void clk_put(struct clk *clk) | ||
177 | { | ||
178 | } | ||
179 | |||
180 | int clk_enable(struct clk *clk) | ||
181 | { | ||
182 | return 0; | ||
183 | } | ||
184 | |||
185 | void clk_disable(struct clk *clk) | ||
186 | { | ||
187 | } | ||
188 | |||
189 | unsigned long clk_get_rate(struct clk *clk) | ||
190 | { | ||
191 | return clk->get_rate(); | ||
192 | } | ||
193 | |||
194 | int imx_clocks_init(void) | ||
195 | { | ||
196 | int i; | ||
197 | |||
198 | mutex_lock(&clocks_mutex); | ||
199 | for (i = 0; i < ARRAY_SIZE(clks); i++) | ||
200 | list_add(&clks[i]->node, &clocks); | ||
201 | mutex_unlock(&clocks_mutex); | ||
202 | |||
203 | return 0; | ||
204 | } | ||
205 | |||