1// SPDX-License-Identifier: GPL-2.0
2/*
3 * arch/sh/kernel/cpu/sh3/clock-sh7705.c
4 *
5 * SH7705 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
22/*
23 * SH7705 uses the same divisors as the generic SH-3 case, it's just the
24 * FRQCR layout that is a bit different..
25 */
26static int stc_multipliers[] = { 1, 2, 3, 4, 6, 1, 1, 1 };
27static int ifc_divisors[] = { 1, 2, 3, 4, 1, 1, 1, 1 };
28static int pfc_divisors[] = { 1, 2, 3, 4, 6, 1, 1, 1 };
29
30static void master_clk_init(struct clk *clk)
31{
32 clk->rate *= pfc_divisors[__raw_readw(FRQCR) & 0x0003];
33}
34
35static struct sh_clk_ops sh7705_master_clk_ops = {
36 .init = master_clk_init,
37};
38
39static unsigned long module_clk_recalc(struct clk *clk)
40{
41 int idx = __raw_readw(addr: FRQCR) & 0x0003;
42 return clk->parent->rate / pfc_divisors[idx];
43}
44
45static struct sh_clk_ops sh7705_module_clk_ops = {
46 .recalc = module_clk_recalc,
47};
48
49static unsigned long bus_clk_recalc(struct clk *clk)
50{
51 int idx = (__raw_readw(FRQCR) & 0x0300) >> 8;
52 return clk->parent->rate / stc_multipliers[idx];
53}
54
55static struct sh_clk_ops sh7705_bus_clk_ops = {
56 .recalc = bus_clk_recalc,
57};
58
59static unsigned long cpu_clk_recalc(struct clk *clk)
60{
61 int idx = (__raw_readw(FRQCR) & 0x0030) >> 4;
62 return clk->parent->rate / ifc_divisors[idx];
63}
64
65static struct sh_clk_ops sh7705_cpu_clk_ops = {
66 .recalc = cpu_clk_recalc,
67};
68
69static struct sh_clk_ops *sh7705_clk_ops[] = {
70 &sh7705_master_clk_ops,
71 &sh7705_module_clk_ops,
72 &sh7705_bus_clk_ops,
73 &sh7705_cpu_clk_ops,
74};
75
76void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
77{
78 if (idx < ARRAY_SIZE(sh7705_clk_ops))
79 *ops = sh7705_clk_ops[idx];
80}
81
82

source code of linux/arch/sh/kernel/cpu/sh3/clock-sh7705.c