1 /*
2 * Copyright 2012 Freescale Semiconductor, Inc.
3 * Copyright 2012 Linaro Ltd.
4 *
5 * The code contained herein is licensed under the GNU General Public
6 * License. You may obtain a copy of the GNU General Public License
7 * Version 2 or later at the following locations:
8 *
9 * http://www.opensource.org/licenses/gpl-license.html
10 * http://www.gnu.org/copyleft/gpl.html
11 */
12
13 #include <linux/clk.h>
14 #include <linux/clk-provider.h>
15 #include <linux/io.h>
16 #include <linux/slab.h>
17 #include <linux/jiffies.h>
18 #include <linux/err.h>
19 #include "clk.h"
20
clk_busy_wait(void __iomem * reg,u8 shift)21 static int clk_busy_wait(void __iomem *reg, u8 shift)
22 {
23 unsigned long timeout = jiffies + msecs_to_jiffies(10);
24
25 while (readl_relaxed(reg) & (1 << shift))
26 if (time_after(jiffies, timeout))
27 return -ETIMEDOUT;
28
29 return 0;
30 }
31
32 struct clk_busy_divider {
33 struct clk_divider div;
34 const struct clk_ops *div_ops;
35 void __iomem *reg;
36 u8 shift;
37 };
38
to_clk_busy_divider(struct clk_hw * hw)39 static inline struct clk_busy_divider *to_clk_busy_divider(struct clk_hw *hw)
40 {
41 struct clk_divider *div = to_clk_divider(hw);
42
43 return container_of(div, struct clk_busy_divider, div);
44 }
45
clk_busy_divider_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)46 static unsigned long clk_busy_divider_recalc_rate(struct clk_hw *hw,
47 unsigned long parent_rate)
48 {
49 struct clk_busy_divider *busy = to_clk_busy_divider(hw);
50
51 return busy->div_ops->recalc_rate(&busy->div.hw, parent_rate);
52 }
53
clk_busy_divider_round_rate(struct clk_hw * hw,unsigned long rate,unsigned long * prate)54 static long clk_busy_divider_round_rate(struct clk_hw *hw, unsigned long rate,
55 unsigned long *prate)
56 {
57 struct clk_busy_divider *busy = to_clk_busy_divider(hw);
58
59 return busy->div_ops->round_rate(&busy->div.hw, rate, prate);
60 }
61
clk_busy_divider_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)62 static int clk_busy_divider_set_rate(struct clk_hw *hw, unsigned long rate,
63 unsigned long parent_rate)
64 {
65 struct clk_busy_divider *busy = to_clk_busy_divider(hw);
66 int ret;
67
68 ret = busy->div_ops->set_rate(&busy->div.hw, rate, parent_rate);
69 if (!ret)
70 ret = clk_busy_wait(busy->reg, busy->shift);
71
72 return ret;
73 }
74
75 static const struct clk_ops clk_busy_divider_ops = {
76 .recalc_rate = clk_busy_divider_recalc_rate,
77 .round_rate = clk_busy_divider_round_rate,
78 .set_rate = clk_busy_divider_set_rate,
79 };
80
imx_clk_busy_divider(const char * name,const char * parent_name,void __iomem * reg,u8 shift,u8 width,void __iomem * busy_reg,u8 busy_shift)81 struct clk *imx_clk_busy_divider(const char *name, const char *parent_name,
82 void __iomem *reg, u8 shift, u8 width,
83 void __iomem *busy_reg, u8 busy_shift)
84 {
85 struct clk_busy_divider *busy;
86 struct clk *clk;
87 struct clk_init_data init;
88
89 busy = kzalloc(sizeof(*busy), GFP_KERNEL);
90 if (!busy)
91 return ERR_PTR(-ENOMEM);
92
93 busy->reg = busy_reg;
94 busy->shift = busy_shift;
95
96 busy->div.reg = reg;
97 busy->div.shift = shift;
98 busy->div.width = width;
99 busy->div.lock = &imx_ccm_lock;
100 busy->div_ops = &clk_divider_ops;
101
102 init.name = name;
103 init.ops = &clk_busy_divider_ops;
104 init.flags = CLK_SET_RATE_PARENT | CLK_IS_CRITICAL;
105 init.parent_names = &parent_name;
106 init.num_parents = 1;
107
108 busy->div.hw.init = &init;
109
110 clk = clk_register(NULL, &busy->div.hw);
111 if (IS_ERR(clk))
112 kfree(busy);
113
114 return clk;
115 }
116
117 struct clk_busy_mux {
118 struct clk_mux mux;
119 const struct clk_ops *mux_ops;
120 void __iomem *reg;
121 u8 shift;
122 };
123
to_clk_busy_mux(struct clk_hw * hw)124 static inline struct clk_busy_mux *to_clk_busy_mux(struct clk_hw *hw)
125 {
126 struct clk_mux *mux = to_clk_mux(hw);
127
128 return container_of(mux, struct clk_busy_mux, mux);
129 }
130
clk_busy_mux_get_parent(struct clk_hw * hw)131 static u8 clk_busy_mux_get_parent(struct clk_hw *hw)
132 {
133 struct clk_busy_mux *busy = to_clk_busy_mux(hw);
134
135 return busy->mux_ops->get_parent(&busy->mux.hw);
136 }
137
clk_busy_mux_set_parent(struct clk_hw * hw,u8 index)138 static int clk_busy_mux_set_parent(struct clk_hw *hw, u8 index)
139 {
140 struct clk_busy_mux *busy = to_clk_busy_mux(hw);
141 int ret;
142
143 ret = busy->mux_ops->set_parent(&busy->mux.hw, index);
144 if (!ret)
145 ret = clk_busy_wait(busy->reg, busy->shift);
146
147 return ret;
148 }
149
150 static const struct clk_ops clk_busy_mux_ops = {
151 .get_parent = clk_busy_mux_get_parent,
152 .set_parent = clk_busy_mux_set_parent,
153 };
154
imx_clk_busy_mux(const char * name,void __iomem * reg,u8 shift,u8 width,void __iomem * busy_reg,u8 busy_shift,const char * const * parent_names,int num_parents)155 struct clk *imx_clk_busy_mux(const char *name, void __iomem *reg, u8 shift,
156 u8 width, void __iomem *busy_reg, u8 busy_shift,
157 const char * const *parent_names, int num_parents)
158 {
159 struct clk_busy_mux *busy;
160 struct clk *clk;
161 struct clk_init_data init;
162
163 busy = kzalloc(sizeof(*busy), GFP_KERNEL);
164 if (!busy)
165 return ERR_PTR(-ENOMEM);
166
167 busy->reg = busy_reg;
168 busy->shift = busy_shift;
169
170 busy->mux.reg = reg;
171 busy->mux.shift = shift;
172 busy->mux.mask = BIT(width) - 1;
173 busy->mux.lock = &imx_ccm_lock;
174 busy->mux_ops = &clk_mux_ops;
175
176 init.name = name;
177 init.ops = &clk_busy_mux_ops;
178 init.flags = CLK_IS_CRITICAL;
179 init.parent_names = parent_names;
180 init.num_parents = num_parents;
181
182 busy->mux.hw.init = &init;
183
184 clk = clk_register(NULL, &busy->mux.hw);
185 if (IS_ERR(clk))
186 kfree(busy);
187
188 return clk;
189 }
190