xref: /openbmc/linux/arch/sh/kernel/cpu/sh3/clock-sh7706.c (revision feac8c8b)
1 /*
2  * arch/sh/kernel/cpu/sh3/clock-sh7706.c
3  *
4  * SH7706 support for the clock framework
5  *
6  *  Copyright (C) 2006  Takashi YOSHII
7  *
8  * Based on arch/sh/kernel/cpu/sh3/clock-sh7709.c
9  *  Copyright (C) 2005  Andriy Skulysh
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 stc_multipliers[] = { 1, 2, 4, 1, 3, 6, 1, 1 };
22 static int ifc_divisors[]    = { 1, 2, 4, 1, 3, 1, 1, 1 };
23 static int pfc_divisors[]    = { 1, 2, 4, 1, 3, 6, 1, 1 };
24 
25 static void master_clk_init(struct clk *clk)
26 {
27 	int frqcr = __raw_readw(FRQCR);
28 	int idx = ((frqcr & 0x2000) >> 11) | (frqcr & 0x0003);
29 
30 	clk->rate *= pfc_divisors[idx];
31 }
32 
33 static struct sh_clk_ops sh7706_master_clk_ops = {
34 	.init		= master_clk_init,
35 };
36 
37 static unsigned long module_clk_recalc(struct clk *clk)
38 {
39 	int frqcr = __raw_readw(FRQCR);
40 	int idx = ((frqcr & 0x2000) >> 11) | (frqcr & 0x0003);
41 
42 	return clk->parent->rate / pfc_divisors[idx];
43 }
44 
45 static struct sh_clk_ops sh7706_module_clk_ops = {
46 	.recalc		= module_clk_recalc,
47 };
48 
49 static unsigned long bus_clk_recalc(struct clk *clk)
50 {
51 	int frqcr = __raw_readw(FRQCR);
52 	int idx = ((frqcr & 0x8000) >> 13) | ((frqcr & 0x0030) >> 4);
53 
54 	return clk->parent->rate / stc_multipliers[idx];
55 }
56 
57 static struct sh_clk_ops sh7706_bus_clk_ops = {
58 	.recalc		= bus_clk_recalc,
59 };
60 
61 static unsigned long cpu_clk_recalc(struct clk *clk)
62 {
63 	int frqcr = __raw_readw(FRQCR);
64 	int idx = ((frqcr & 0x4000) >> 12) | ((frqcr & 0x000c) >> 2);
65 
66 	return clk->parent->rate / ifc_divisors[idx];
67 }
68 
69 static struct sh_clk_ops sh7706_cpu_clk_ops = {
70 	.recalc		= cpu_clk_recalc,
71 };
72 
73 static struct sh_clk_ops *sh7706_clk_ops[] = {
74 	&sh7706_master_clk_ops,
75 	&sh7706_module_clk_ops,
76 	&sh7706_bus_clk_ops,
77 	&sh7706_cpu_clk_ops,
78 };
79 
80 void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
81 {
82 	if (idx < ARRAY_SIZE(sh7706_clk_ops))
83 		*ops = sh7706_clk_ops[idx];
84 }
85