1/*
2 * arch/sh/kernel/cpu/sh3/clock-sh7705.c
3 *
4 * SH7705 support for the clock framework
5 *
6 *  Copyright (C) 2005  Paul Mundt
7 *
8 * FRQCR parsing hacked out of arch/sh/kernel/time.c
9 *
10 *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
11 *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
12 *  Copyright (C) 2002, 2003, 2004  Paul Mundt
13 *  Copyright (C) 2002  M. R. Brown  <mrbrown@linux-sh.org>
14 *
15 * This file is subject to the terms and conditions of the GNU General Public
16 * License.  See the file "COPYING" in the main directory of this archive
17 * for more details.
18 */
19#include <linux/init.h>
20#include <linux/kernel.h>
21#include <asm/clock.h>
22#include <asm/freq.h>
23#include <asm/io.h>
24
25/*
26 * SH7705 uses the same divisors as the generic SH-3 case, it's just the
27 * FRQCR layout that is a bit different..
28 */
29static int stc_multipliers[] = { 1, 2, 3, 4, 6, 1, 1, 1 };
30static int ifc_divisors[]    = { 1, 2, 3, 4, 1, 1, 1, 1 };
31static int pfc_divisors[]    = { 1, 2, 3, 4, 6, 1, 1, 1 };
32
33static void master_clk_init(struct clk *clk)
34{
35	clk->rate *= pfc_divisors[ctrl_inw(FRQCR) & 0x0003];
36}
37
38static struct clk_ops sh7705_master_clk_ops = {
39	.init		= master_clk_init,
40};
41
42static void module_clk_recalc(struct clk *clk)
43{
44	int idx = ctrl_inw(FRQCR) & 0x0003;
45	clk->rate = clk->parent->rate / pfc_divisors[idx];
46}
47
48static struct clk_ops sh7705_module_clk_ops = {
49	.recalc		= module_clk_recalc,
50};
51
52static void bus_clk_recalc(struct clk *clk)
53{
54	int idx = (ctrl_inw(FRQCR) & 0x0300) >> 8;
55	clk->rate = clk->parent->rate / stc_multipliers[idx];
56}
57
58static struct clk_ops sh7705_bus_clk_ops = {
59	.recalc		= bus_clk_recalc,
60};
61
62static void cpu_clk_recalc(struct clk *clk)
63{
64	int idx = (ctrl_inw(FRQCR) & 0x0030) >> 4;
65	clk->rate = clk->parent->rate / ifc_divisors[idx];
66}
67
68static struct clk_ops sh7705_cpu_clk_ops = {
69	.recalc		= cpu_clk_recalc,
70};
71
72static struct clk_ops *sh7705_clk_ops[] = {
73	&sh7705_master_clk_ops,
74	&sh7705_module_clk_ops,
75	&sh7705_bus_clk_ops,
76	&sh7705_cpu_clk_ops,
77};
78
79void __init arch_init_clk_ops(struct clk_ops **ops, int idx)
80{
81	if (idx < ARRAY_SIZE(sh7705_clk_ops))
82		*ops = sh7705_clk_ops[idx];
83}
84