1 /*
2  * arch/sh/kernel/cpu/sh4a/clock-sh7763.c
3  *
4  * SH7763 support for the clock framework
5  *
6  *  Copyright (C) 2005  Paul Mundt
7  *  Copyright (C) 2007  Yoshihiro Shimoda
8  *
9  * This file is subject to the terms and conditions of the GNU General Public
10  * License.  See the file "COPYING" in the main directory of this archive
11  * for more details.
12  */
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <asm/clock.h>
16 #include <asm/freq.h>
17 #include <asm/io.h>
18 
19 static int bfc_divisors[] = { 1, 1, 1, 8, 1, 1, 1, 1 };
20 static int p0fc_divisors[] = { 1, 1, 1, 8, 1, 1, 1, 1 };
21 static int cfc_divisors[] = { 1, 1, 4, 1, 1, 1, 1, 1 };
22 
23 static void master_clk_init(struct clk *clk)
24 {
25 	clk->rate *= p0fc_divisors[(ctrl_inl(FRQCR) >> 4) & 0x07];
26 }
27 
28 static struct clk_ops sh7763_master_clk_ops = {
29 	.init		= master_clk_init,
30 };
31 
32 static unsigned long module_clk_recalc(struct clk *clk)
33 {
34 	int idx = ((ctrl_inl(FRQCR) >> 4) & 0x07);
35 	return clk->parent->rate / p0fc_divisors[idx];
36 }
37 
38 static struct clk_ops sh7763_module_clk_ops = {
39 	.recalc		= module_clk_recalc,
40 };
41 
42 static unsigned long bus_clk_recalc(struct clk *clk)
43 {
44 	int idx = ((ctrl_inl(FRQCR) >> 16) & 0x07);
45 	return clk->parent->rate / bfc_divisors[idx];
46 }
47 
48 static struct clk_ops sh7763_bus_clk_ops = {
49 	.recalc		= bus_clk_recalc,
50 };
51 
52 static struct clk_ops sh7763_cpu_clk_ops = {
53 	.recalc		= followparent_recalc,
54 };
55 
56 static struct clk_ops *sh7763_clk_ops[] = {
57 	&sh7763_master_clk_ops,
58 	&sh7763_module_clk_ops,
59 	&sh7763_bus_clk_ops,
60 	&sh7763_cpu_clk_ops,
61 };
62 
63 void __init arch_init_clk_ops(struct clk_ops **ops, int idx)
64 {
65 	if (idx < ARRAY_SIZE(sh7763_clk_ops))
66 		*ops = sh7763_clk_ops[idx];
67 }
68 
69 static unsigned long shyway_clk_recalc(struct clk *clk)
70 {
71 	int idx = ((ctrl_inl(FRQCR) >> 20) & 0x07);
72 	return clk->parent->rate / cfc_divisors[idx];
73 }
74 
75 static struct clk_ops sh7763_shyway_clk_ops = {
76 	.recalc		= shyway_clk_recalc,
77 };
78 
79 static struct clk sh7763_shyway_clk = {
80 	.name		= "shyway_clk",
81 	.flags		= CLK_ENABLE_ON_INIT,
82 	.ops		= &sh7763_shyway_clk_ops,
83 };
84 
85 /*
86  * Additional SH7763-specific on-chip clocks that aren't already part of the
87  * clock framework
88  */
89 static struct clk *sh7763_onchip_clocks[] = {
90 	&sh7763_shyway_clk,
91 };
92 
93 int __init arch_clk_init(void)
94 {
95 	struct clk *clk;
96 	int i, ret = 0;
97 
98 	cpg_clk_init();
99 
100 	clk = clk_get(NULL, "master_clk");
101 	for (i = 0; i < ARRAY_SIZE(sh7763_onchip_clocks); i++) {
102 		struct clk *clkp = sh7763_onchip_clocks[i];
103 
104 		clkp->parent = clk;
105 		ret |= clk_register(clkp);
106 	}
107 
108 	clk_put(clk);
109 
110 	return ret;
111 }
112