xref: /openbmc/linux/arch/sh/kernel/cpu/sh3/clock-sh7712.c (revision 4f3db074)
1 /*
2  * arch/sh/kernel/cpu/sh3/clock-sh7712.c
3  *
4  * SH7712 support for the clock framework
5  *
6  *  Copyright (C) 2007  Andrew Murray <amurray@mpc-data.co.uk>
7  *
8  * Based on arch/sh/kernel/cpu/sh3/clock-sh3.c
9  *  Copyright (C) 2005  Paul Mundt
10  *
11  * This file is subject to the terms and conditions of the GNU General Public
12  * License.  See the file "COPYING" in the main directory of this archive
13  * for more details.
14  */
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <asm/clock.h>
18 #include <asm/freq.h>
19 #include <asm/io.h>
20 
21 static int multipliers[] = { 1, 2, 3 };
22 static int divisors[]    = { 1, 2, 3, 4, 6 };
23 
24 static void master_clk_init(struct clk *clk)
25 {
26 	int frqcr = __raw_readw(FRQCR);
27 	int idx = (frqcr & 0x0300) >> 8;
28 
29 	clk->rate *= multipliers[idx];
30 }
31 
32 static struct sh_clk_ops sh7712_master_clk_ops = {
33 	.init		= master_clk_init,
34 };
35 
36 static unsigned long module_clk_recalc(struct clk *clk)
37 {
38 	int frqcr = __raw_readw(FRQCR);
39 	int idx = frqcr & 0x0007;
40 
41 	return clk->parent->rate / divisors[idx];
42 }
43 
44 static struct sh_clk_ops sh7712_module_clk_ops = {
45 	.recalc		= module_clk_recalc,
46 };
47 
48 static unsigned long cpu_clk_recalc(struct clk *clk)
49 {
50 	int frqcr = __raw_readw(FRQCR);
51 	int idx = (frqcr & 0x0030) >> 4;
52 
53 	return clk->parent->rate / divisors[idx];
54 }
55 
56 static struct sh_clk_ops sh7712_cpu_clk_ops = {
57 	.recalc		= cpu_clk_recalc,
58 };
59 
60 static struct sh_clk_ops *sh7712_clk_ops[] = {
61 	&sh7712_master_clk_ops,
62 	&sh7712_module_clk_ops,
63 	&sh7712_cpu_clk_ops,
64 };
65 
66 void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
67 {
68 	if (idx < ARRAY_SIZE(sh7712_clk_ops))
69 		*ops = sh7712_clk_ops[idx];
70 }
71 
72