Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
4 */
5
6#include <linux/clk-provider.h>
7#include <linux/clkdev.h>
8#include <linux/clk/at91_pmc.h>
9#include <linux/of.h>
10#include <linux/mfd/syscon.h>
11#include <linux/regmap.h>
12
13#include "pmc.h"
14
15#define SYSTEM_MAX_ID 31
16
17#define SYSTEM_MAX_NAME_SZ 32
18
19#define to_clk_system(hw) container_of(hw, struct clk_system, hw)
20struct clk_system {
21 struct clk_hw hw;
22 struct regmap *regmap;
23 struct at91_clk_pms pms;
24 u8 id;
25};
26
27static inline int is_pck(int id)
28{
29 return (id >= 8) && (id <= 15);
30}
31
32static inline bool clk_system_ready(struct regmap *regmap, int id)
33{
34 unsigned int status;
35
36 regmap_read(regmap, AT91_PMC_SR, &status);
37
38 return !!(status & (1 << id));
39}
40
41static int clk_system_prepare(struct clk_hw *hw)
42{
43 struct clk_system *sys = to_clk_system(hw);
44
45 regmap_write(sys->regmap, AT91_PMC_SCER, 1 << sys->id);
46
47 if (!is_pck(sys->id))
48 return 0;
49
50 while (!clk_system_ready(sys->regmap, sys->id))
51 cpu_relax();
52
53 return 0;
54}
55
56static void clk_system_unprepare(struct clk_hw *hw)
57{
58 struct clk_system *sys = to_clk_system(hw);
59
60 regmap_write(sys->regmap, AT91_PMC_SCDR, 1 << sys->id);
61}
62
63static int clk_system_is_prepared(struct clk_hw *hw)
64{
65 struct clk_system *sys = to_clk_system(hw);
66 unsigned int status;
67
68 regmap_read(sys->regmap, AT91_PMC_SCSR, &status);
69
70 if (!(status & (1 << sys->id)))
71 return 0;
72
73 if (!is_pck(sys->id))
74 return 1;
75
76 regmap_read(sys->regmap, AT91_PMC_SR, &status);
77
78 return !!(status & (1 << sys->id));
79}
80
81static int clk_system_save_context(struct clk_hw *hw)
82{
83 struct clk_system *sys = to_clk_system(hw);
84
85 sys->pms.status = clk_system_is_prepared(hw);
86
87 return 0;
88}
89
90static void clk_system_restore_context(struct clk_hw *hw)
91{
92 struct clk_system *sys = to_clk_system(hw);
93
94 if (sys->pms.status)
95 clk_system_prepare(&sys->hw);
96}
97
98static const struct clk_ops system_ops = {
99 .prepare = clk_system_prepare,
100 .unprepare = clk_system_unprepare,
101 .is_prepared = clk_system_is_prepared,
102 .save_context = clk_system_save_context,
103 .restore_context = clk_system_restore_context,
104};
105
106struct clk_hw * __init
107at91_clk_register_system(struct regmap *regmap, const char *name,
108 const char *parent_name, u8 id)
109{
110 struct clk_system *sys;
111 struct clk_hw *hw;
112 struct clk_init_data init;
113 int ret;
114
115 if (!parent_name || id > SYSTEM_MAX_ID)
116 return ERR_PTR(-EINVAL);
117
118 sys = kzalloc(sizeof(*sys), GFP_KERNEL);
119 if (!sys)
120 return ERR_PTR(-ENOMEM);
121
122 init.name = name;
123 init.ops = &system_ops;
124 init.parent_names = &parent_name;
125 init.num_parents = 1;
126 init.flags = CLK_SET_RATE_PARENT;
127
128 sys->id = id;
129 sys->hw.init = &init;
130 sys->regmap = regmap;
131
132 hw = &sys->hw;
133 ret = clk_hw_register(NULL, &sys->hw);
134 if (ret) {
135 kfree(sys);
136 hw = ERR_PTR(ret);
137 }
138
139 return hw;
140}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
4 */
5
6#include <linux/clk-provider.h>
7#include <linux/clkdev.h>
8#include <linux/clk/at91_pmc.h>
9#include <linux/of.h>
10#include <linux/mfd/syscon.h>
11#include <linux/regmap.h>
12
13#include "pmc.h"
14
15#define SYSTEM_MAX_ID 31
16
17#define SYSTEM_MAX_NAME_SZ 32
18
19#define to_clk_system(hw) container_of(hw, struct clk_system, hw)
20struct clk_system {
21 struct clk_hw hw;
22 struct regmap *regmap;
23 u8 id;
24};
25
26static inline int is_pck(int id)
27{
28 return (id >= 8) && (id <= 15);
29}
30
31static inline bool clk_system_ready(struct regmap *regmap, int id)
32{
33 unsigned int status;
34
35 regmap_read(regmap, AT91_PMC_SR, &status);
36
37 return status & (1 << id) ? 1 : 0;
38}
39
40static int clk_system_prepare(struct clk_hw *hw)
41{
42 struct clk_system *sys = to_clk_system(hw);
43
44 regmap_write(sys->regmap, AT91_PMC_SCER, 1 << sys->id);
45
46 if (!is_pck(sys->id))
47 return 0;
48
49 while (!clk_system_ready(sys->regmap, sys->id))
50 cpu_relax();
51
52 return 0;
53}
54
55static void clk_system_unprepare(struct clk_hw *hw)
56{
57 struct clk_system *sys = to_clk_system(hw);
58
59 regmap_write(sys->regmap, AT91_PMC_SCDR, 1 << sys->id);
60}
61
62static int clk_system_is_prepared(struct clk_hw *hw)
63{
64 struct clk_system *sys = to_clk_system(hw);
65 unsigned int status;
66
67 regmap_read(sys->regmap, AT91_PMC_SCSR, &status);
68
69 if (!(status & (1 << sys->id)))
70 return 0;
71
72 if (!is_pck(sys->id))
73 return 1;
74
75 regmap_read(sys->regmap, AT91_PMC_SR, &status);
76
77 return status & (1 << sys->id) ? 1 : 0;
78}
79
80static const struct clk_ops system_ops = {
81 .prepare = clk_system_prepare,
82 .unprepare = clk_system_unprepare,
83 .is_prepared = clk_system_is_prepared,
84};
85
86struct clk_hw * __init
87at91_clk_register_system(struct regmap *regmap, const char *name,
88 const char *parent_name, u8 id)
89{
90 struct clk_system *sys;
91 struct clk_hw *hw;
92 struct clk_init_data init;
93 int ret;
94
95 if (!parent_name || id > SYSTEM_MAX_ID)
96 return ERR_PTR(-EINVAL);
97
98 sys = kzalloc(sizeof(*sys), GFP_KERNEL);
99 if (!sys)
100 return ERR_PTR(-ENOMEM);
101
102 init.name = name;
103 init.ops = &system_ops;
104 init.parent_names = &parent_name;
105 init.num_parents = 1;
106 init.flags = CLK_SET_RATE_PARENT;
107
108 sys->id = id;
109 sys->hw.init = &init;
110 sys->regmap = regmap;
111
112 hw = &sys->hw;
113 ret = clk_hw_register(NULL, &sys->hw);
114 if (ret) {
115 kfree(sys);
116 hw = ERR_PTR(ret);
117 }
118
119 return hw;
120}