xref: /linux/arch/sh/kernel/cpu/sh4a/clock-shx3.c (revision a234ca0faa65dcd5cc473915bd925130ebb7b74b)
1 /*
2  * arch/sh/kernel/cpu/sh4/clock-shx3.c
3  *
4  * SH-X3 support for the clock framework
5  *
6  *  Copyright (C) 2006-2007  Renesas Technology Corp.
7  *  Copyright (C) 2006-2007  Renesas Solutions Corp.
8  *  Copyright (C) 2006-2007  Paul Mundt
9  *
10  * This file is subject to the terms and conditions of the GNU General Public
11  * License.  See the file "COPYING" in the main directory of this archive
12  * for more details.
13  */
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/io.h>
17 #include <asm/clkdev.h>
18 #include <asm/clock.h>
19 #include <asm/freq.h>
20 
21 static int ifc_divisors[] = { 1, 2, 4 ,6 };
22 static int bfc_divisors[] = { 1, 1, 1, 1, 1, 12, 16, 18, 24, 32, 36, 48 };
23 static int pfc_divisors[] = { 1, 1, 1, 1, 1, 1, 1, 18, 24, 32, 36, 48 };
24 static int cfc_divisors[] = { 1, 1, 4, 6 };
25 
26 #define IFC_POS		28
27 #define IFC_MSK		0x0003
28 #define BFC_MSK		0x000f
29 #define PFC_MSK		0x000f
30 #define CFC_MSK		0x0003
31 #define BFC_POS		16
32 #define PFC_POS		0
33 #define CFC_POS		20
34 
35 static void master_clk_init(struct clk *clk)
36 {
37 	clk->rate *= pfc_divisors[(__raw_readl(FRQCR) >> PFC_POS) & PFC_MSK];
38 }
39 
40 static struct clk_ops shx3_master_clk_ops = {
41 	.init		= master_clk_init,
42 };
43 
44 static unsigned long module_clk_recalc(struct clk *clk)
45 {
46 	int idx = ((__raw_readl(FRQCR) >> PFC_POS) & PFC_MSK);
47 	return clk->parent->rate / pfc_divisors[idx];
48 }
49 
50 static struct clk_ops shx3_module_clk_ops = {
51 	.recalc		= module_clk_recalc,
52 };
53 
54 static unsigned long bus_clk_recalc(struct clk *clk)
55 {
56 	int idx = ((__raw_readl(FRQCR) >> BFC_POS) & BFC_MSK);
57 	return clk->parent->rate / bfc_divisors[idx];
58 }
59 
60 static struct clk_ops shx3_bus_clk_ops = {
61 	.recalc		= bus_clk_recalc,
62 };
63 
64 static unsigned long cpu_clk_recalc(struct clk *clk)
65 {
66 	int idx = ((__raw_readl(FRQCR) >> IFC_POS) & IFC_MSK);
67 	return clk->parent->rate / ifc_divisors[idx];
68 }
69 
70 static struct clk_ops shx3_cpu_clk_ops = {
71 	.recalc		= cpu_clk_recalc,
72 };
73 
74 static struct clk_ops *shx3_clk_ops[] = {
75 	&shx3_master_clk_ops,
76 	&shx3_module_clk_ops,
77 	&shx3_bus_clk_ops,
78 	&shx3_cpu_clk_ops,
79 };
80 
81 void __init arch_init_clk_ops(struct clk_ops **ops, int idx)
82 {
83 	if (idx < ARRAY_SIZE(shx3_clk_ops))
84 		*ops = shx3_clk_ops[idx];
85 }
86 
87 static unsigned long shyway_clk_recalc(struct clk *clk)
88 {
89 	int idx = ((__raw_readl(FRQCR) >> CFC_POS) & CFC_MSK);
90 	return clk->parent->rate / cfc_divisors[idx];
91 }
92 
93 static struct clk_ops shx3_shyway_clk_ops = {
94 	.recalc		= shyway_clk_recalc,
95 };
96 
97 static struct clk shx3_shyway_clk = {
98 	.flags		= CLK_ENABLE_ON_INIT,
99 	.ops		= &shx3_shyway_clk_ops,
100 };
101 
102 /*
103  * Additional SHx3-specific on-chip clocks that aren't already part of the
104  * clock framework
105  */
106 static struct clk *shx3_onchip_clocks[] = {
107 	&shx3_shyway_clk,
108 };
109 
110 #define CLKDEV_CON_ID(_id, _clk) { .con_id = _id, .clk = _clk }
111 
112 static struct clk_lookup lookups[] = {
113 	/* main clocks */
114 	CLKDEV_CON_ID("shyway_clk", &shx3_shyway_clk),
115 };
116 
117 int __init arch_clk_init(void)
118 {
119 	struct clk *clk;
120 	int i, ret = 0;
121 
122 	cpg_clk_init();
123 
124 	clk = clk_get(NULL, "master_clk");
125 	for (i = 0; i < ARRAY_SIZE(shx3_onchip_clocks); i++) {
126 		struct clk *clkp = shx3_onchip_clocks[i];
127 
128 		clkp->parent = clk;
129 		ret |= clk_register(clkp);
130 	}
131 
132 	clk_put(clk);
133 
134 	clkdev_add_table(lookups, ARRAY_SIZE(lookups));
135 
136 	return ret;
137 }
138