1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * arch/sh/kernel/cpu/sh4a/clock-sh7763.c
4  *
5  * SH7763 support for the clock framework
6  *
7  *  Copyright (C) 2005  Paul Mundt
8  *  Copyright (C) 2007  Yoshihiro Shimoda
9  */
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/io.h>
13 #include <linux/clkdev.h>
14 #include <asm/clock.h>
15 #include <asm/freq.h>
16 #include <asm/io.h>
17 
18 static int bfc_divisors[] = { 1, 1, 1, 8, 1, 1, 1, 1 };
19 static int p0fc_divisors[] = { 1, 1, 1, 8, 1, 1, 1, 1 };
20 static int cfc_divisors[] = { 1, 1, 4, 1, 1, 1, 1, 1 };
21 
22 static void master_clk_init(struct clk *clk)
23 {
24 	clk->rate *= p0fc_divisors[(__raw_readl(FRQCR) >> 4) & 0x07];
25 }
26 
27 static struct sh_clk_ops sh7763_master_clk_ops = {
28 	.init		= master_clk_init,
29 };
30 
31 static unsigned long module_clk_recalc(struct clk *clk)
32 {
33 	int idx = ((__raw_readl(FRQCR) >> 4) & 0x07);
34 	return clk->parent->rate / p0fc_divisors[idx];
35 }
36 
37 static struct sh_clk_ops sh7763_module_clk_ops = {
38 	.recalc		= module_clk_recalc,
39 };
40 
41 static unsigned long bus_clk_recalc(struct clk *clk)
42 {
43 	int idx = ((__raw_readl(FRQCR) >> 16) & 0x07);
44 	return clk->parent->rate / bfc_divisors[idx];
45 }
46 
47 static struct sh_clk_ops sh7763_bus_clk_ops = {
48 	.recalc		= bus_clk_recalc,
49 };
50 
51 static struct sh_clk_ops sh7763_cpu_clk_ops = {
52 	.recalc		= followparent_recalc,
53 };
54 
55 static struct sh_clk_ops *sh7763_clk_ops[] = {
56 	&sh7763_master_clk_ops,
57 	&sh7763_module_clk_ops,
58 	&sh7763_bus_clk_ops,
59 	&sh7763_cpu_clk_ops,
60 };
61 
62 void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
63 {
64 	if (idx < ARRAY_SIZE(sh7763_clk_ops))
65 		*ops = sh7763_clk_ops[idx];
66 }
67 
68 static unsigned long shyway_clk_recalc(struct clk *clk)
69 {
70 	int idx = ((__raw_readl(FRQCR) >> 20) & 0x07);
71 	return clk->parent->rate / cfc_divisors[idx];
72 }
73 
74 static struct sh_clk_ops sh7763_shyway_clk_ops = {
75 	.recalc		= shyway_clk_recalc,
76 };
77 
78 static struct clk sh7763_shyway_clk = {
79 	.flags		= CLK_ENABLE_ON_INIT,
80 	.ops		= &sh7763_shyway_clk_ops,
81 };
82 
83 /*
84  * Additional SH7763-specific on-chip clocks that aren't already part of the
85  * clock framework
86  */
87 static struct clk *sh7763_onchip_clocks[] = {
88 	&sh7763_shyway_clk,
89 };
90 
91 static struct clk_lookup lookups[] = {
92 	/* main clocks */
93 	CLKDEV_CON_ID("shyway_clk", &sh7763_shyway_clk),
94 };
95 
96 int __init arch_clk_init(void)
97 {
98 	struct clk *clk;
99 	int i, ret = 0;
100 
101 	cpg_clk_init();
102 
103 	clk = clk_get(NULL, "master_clk");
104 	for (i = 0; i < ARRAY_SIZE(sh7763_onchip_clocks); i++) {
105 		struct clk *clkp = sh7763_onchip_clocks[i];
106 
107 		clkp->parent = clk;
108 		ret |= clk_register(clkp);
109 	}
110 
111 	clk_put(clk);
112 
113 	clkdev_add_table(lookups, ARRAY_SIZE(lookups));
114 
115 	return ret;
116 }
117