1// SPDX-License-Identifier: GPL-2.0
2/*
3 * arch/sh/kernel/cpu/sh3/clock-sh3.c
4 *
5 * Generic SH-3 support for the clock framework
6 *
7 *  Copyright (C) 2005  Paul Mundt
8 *
9 * FRQCR parsing hacked out of arch/sh/kernel/time.c
10 *
11 *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
12 *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
13 *  Copyright (C) 2002, 2003, 2004  Paul Mundt
14 *  Copyright (C) 2002  M. R. Brown  <mrbrown@linux-sh.org>
15 */
16#include <linux/init.h>
17#include <linux/kernel.h>
18#include <asm/clock.h>
19#include <asm/freq.h>
20#include <asm/io.h>
21
22static int stc_multipliers[] = { 1, 2, 3, 4, 6, 1, 1, 1 };
23static int ifc_divisors[]    = { 1, 2, 3, 4, 1, 1, 1, 1 };
24static int pfc_divisors[]    = { 1, 2, 3, 4, 6, 1, 1, 1 };
25
26static void master_clk_init(struct clk *clk)
27{
28	int frqcr = __raw_readw(FRQCR);
29	int idx = ((frqcr & 0x2000) >> 11) | (frqcr & 0x0003);
30
31	clk->rate *= pfc_divisors[idx];
32}
33
34static struct sh_clk_ops sh3_master_clk_ops = {
35	.init		= master_clk_init,
36};
37
38static unsigned long module_clk_recalc(struct clk *clk)
39{
40	int frqcr = __raw_readw(FRQCR);
41	int idx = ((frqcr & 0x2000) >> 11) | (frqcr & 0x0003);
42
43	return clk->parent->rate / pfc_divisors[idx];
44}
45
46static struct sh_clk_ops sh3_module_clk_ops = {
47	.recalc		= module_clk_recalc,
48};
49
50static unsigned long bus_clk_recalc(struct clk *clk)
51{
52	int frqcr = __raw_readw(FRQCR);
53	int idx = ((frqcr & 0x8000) >> 13) | ((frqcr & 0x0030) >> 4);
54
55	return clk->parent->rate / stc_multipliers[idx];
56}
57
58static struct sh_clk_ops sh3_bus_clk_ops = {
59	.recalc		= bus_clk_recalc,
60};
61
62static unsigned long cpu_clk_recalc(struct clk *clk)
63{
64	int frqcr = __raw_readw(FRQCR);
65	int idx = ((frqcr & 0x4000) >> 12) | ((frqcr & 0x000c) >> 2);
66
67	return clk->parent->rate / ifc_divisors[idx];
68}
69
70static struct sh_clk_ops sh3_cpu_clk_ops = {
71	.recalc		= cpu_clk_recalc,
72};
73
74static struct sh_clk_ops *sh3_clk_ops[] = {
75	&sh3_master_clk_ops,
76	&sh3_module_clk_ops,
77	&sh3_bus_clk_ops,
78	&sh3_cpu_clk_ops,
79};
80
81void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
82{
83	if (idx < ARRAY_SIZE(sh3_clk_ops))
84		*ops = sh3_clk_ops[idx];
85}
86
87