1// SPDX-License-Identifier: GPL-2.0
2/***************************************************************************/
3
4/*
5 * clk.c -- general ColdFire CPU kernel clk handling
6 *
7 * Copyright (C) 2009, Greg Ungerer (gerg@snapgear.com)
8 */
9
10/***************************************************************************/
11
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/platform_device.h>
15#include <linux/mutex.h>
16#include <linux/clk.h>
17#include <linux/io.h>
18#include <linux/err.h>
19#include <asm/coldfire.h>
20#include <asm/mcfsim.h>
21#include <asm/mcfclk.h>
22
23static DEFINE_SPINLOCK(clk_lock);
24
25#ifdef MCFPM_PPMCR0
26/*
27 * For more advanced ColdFire parts that have clocks that can be enabled
28 * we supply enable/disable functions. These must properly define their
29 * clocks in their platform specific code.
30 */
31void __clk_init_enabled(struct clk *clk)
32{
33 clk->enabled = 1;
34 clk->clk_ops->enable(clk);
35}
36
37void __clk_init_disabled(struct clk *clk)
38{
39 clk->enabled = 0;
40 clk->clk_ops->disable(clk);
41}
42
43static void __clk_enable0(struct clk *clk)
44{
45 __raw_writeb(clk->slot, MCFPM_PPMCR0);
46}
47
48static void __clk_disable0(struct clk *clk)
49{
50 __raw_writeb(clk->slot, MCFPM_PPMSR0);
51}
52
53struct clk_ops clk_ops0 = {
54 .enable = __clk_enable0,
55 .disable = __clk_disable0,
56};
57
58#ifdef MCFPM_PPMCR1
59static void __clk_enable1(struct clk *clk)
60{
61 __raw_writeb(clk->slot, MCFPM_PPMCR1);
62}
63
64static void __clk_disable1(struct clk *clk)
65{
66 __raw_writeb(clk->slot, MCFPM_PPMSR1);
67}
68
69struct clk_ops clk_ops1 = {
70 .enable = __clk_enable1,
71 .disable = __clk_disable1,
72};
73#endif /* MCFPM_PPMCR1 */
74#endif /* MCFPM_PPMCR0 */
75
76int clk_enable(struct clk *clk)
77{
78 unsigned long flags;
79
80 if (!clk)
81 return 0;
82
83 spin_lock_irqsave(&clk_lock, flags);
84 if ((clk->enabled++ == 0) && clk->clk_ops)
85 clk->clk_ops->enable(clk);
86 spin_unlock_irqrestore(lock: &clk_lock, flags);
87
88 return 0;
89}
90EXPORT_SYMBOL(clk_enable);
91
92void clk_disable(struct clk *clk)
93{
94 unsigned long flags;
95
96 if (!clk)
97 return;
98
99 spin_lock_irqsave(&clk_lock, flags);
100 if ((--clk->enabled == 0) && clk->clk_ops)
101 clk->clk_ops->disable(clk);
102 spin_unlock_irqrestore(lock: &clk_lock, flags);
103}
104EXPORT_SYMBOL(clk_disable);
105
106unsigned long clk_get_rate(struct clk *clk)
107{
108 if (!clk)
109 return 0;
110
111 return clk->rate;
112}
113EXPORT_SYMBOL(clk_get_rate);
114
115/* dummy functions, should not be called */
116long clk_round_rate(struct clk *clk, unsigned long rate)
117{
118 WARN_ON(clk);
119 return 0;
120}
121EXPORT_SYMBOL(clk_round_rate);
122
123int clk_set_rate(struct clk *clk, unsigned long rate)
124{
125 WARN_ON(clk);
126 return 0;
127}
128EXPORT_SYMBOL(clk_set_rate);
129
130int clk_set_parent(struct clk *clk, struct clk *parent)
131{
132 WARN_ON(clk);
133 return 0;
134}
135EXPORT_SYMBOL(clk_set_parent);
136
137struct clk *clk_get_parent(struct clk *clk)
138{
139 WARN_ON(clk);
140 return NULL;
141}
142EXPORT_SYMBOL(clk_get_parent);
143
144/***************************************************************************/
145

source code of linux/arch/m68k/coldfire/clk.c