1 /*
2 * Copyright (C) 2016 Maxime Ripard
3 * Maxime Ripard <maxime.ripard@free-electrons.com>
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation; either version 2 of
8 * the License, or (at your option) any later version.
9 */
10
11 #include <linux/clk-provider.h>
12
13 #include "ccu_gate.h"
14
ccu_gate_helper_disable(struct ccu_common * common,u32 gate)15 void ccu_gate_helper_disable(struct ccu_common *common, u32 gate)
16 {
17 unsigned long flags;
18 u32 reg;
19
20 if (!gate)
21 return;
22
23 spin_lock_irqsave(common->lock, flags);
24
25 reg = readl(common->base + common->reg);
26 writel(reg & ~gate, common->base + common->reg);
27
28 spin_unlock_irqrestore(common->lock, flags);
29 }
30
ccu_gate_disable(struct clk_hw * hw)31 static void ccu_gate_disable(struct clk_hw *hw)
32 {
33 struct ccu_gate *cg = hw_to_ccu_gate(hw);
34
35 return ccu_gate_helper_disable(&cg->common, cg->enable);
36 }
37
ccu_gate_helper_enable(struct ccu_common * common,u32 gate)38 int ccu_gate_helper_enable(struct ccu_common *common, u32 gate)
39 {
40 unsigned long flags;
41 u32 reg;
42
43 if (!gate)
44 return 0;
45
46 spin_lock_irqsave(common->lock, flags);
47
48 reg = readl(common->base + common->reg);
49 writel(reg | gate, common->base + common->reg);
50
51 spin_unlock_irqrestore(common->lock, flags);
52
53 return 0;
54 }
55
ccu_gate_enable(struct clk_hw * hw)56 static int ccu_gate_enable(struct clk_hw *hw)
57 {
58 struct ccu_gate *cg = hw_to_ccu_gate(hw);
59
60 return ccu_gate_helper_enable(&cg->common, cg->enable);
61 }
62
ccu_gate_helper_is_enabled(struct ccu_common * common,u32 gate)63 int ccu_gate_helper_is_enabled(struct ccu_common *common, u32 gate)
64 {
65 if (!gate)
66 return 1;
67
68 return readl(common->base + common->reg) & gate;
69 }
70
ccu_gate_is_enabled(struct clk_hw * hw)71 static int ccu_gate_is_enabled(struct clk_hw *hw)
72 {
73 struct ccu_gate *cg = hw_to_ccu_gate(hw);
74
75 return ccu_gate_helper_is_enabled(&cg->common, cg->enable);
76 }
77
ccu_gate_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)78 static unsigned long ccu_gate_recalc_rate(struct clk_hw *hw,
79 unsigned long parent_rate)
80 {
81 struct ccu_gate *cg = hw_to_ccu_gate(hw);
82 unsigned long rate = parent_rate;
83
84 if (cg->common.features & CCU_FEATURE_ALL_PREDIV)
85 rate /= cg->common.prediv;
86
87 return rate;
88 }
89
ccu_gate_round_rate(struct clk_hw * hw,unsigned long rate,unsigned long * prate)90 static long ccu_gate_round_rate(struct clk_hw *hw, unsigned long rate,
91 unsigned long *prate)
92 {
93 struct ccu_gate *cg = hw_to_ccu_gate(hw);
94 int div = 1;
95
96 if (cg->common.features & CCU_FEATURE_ALL_PREDIV)
97 div = cg->common.prediv;
98
99 if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) {
100 unsigned long best_parent = rate;
101
102 if (cg->common.features & CCU_FEATURE_ALL_PREDIV)
103 best_parent *= div;
104 *prate = clk_hw_round_rate(clk_hw_get_parent(hw), best_parent);
105 }
106
107 return *prate / div;
108 }
109
ccu_gate_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)110 static int ccu_gate_set_rate(struct clk_hw *hw, unsigned long rate,
111 unsigned long parent_rate)
112 {
113 /*
114 * We must report success but we can do so unconditionally because
115 * clk_factor_round_rate returns values that ensure this call is a
116 * nop.
117 */
118
119 return 0;
120 }
121
122 const struct clk_ops ccu_gate_ops = {
123 .disable = ccu_gate_disable,
124 .enable = ccu_gate_enable,
125 .is_enabled = ccu_gate_is_enabled,
126 .round_rate = ccu_gate_round_rate,
127 .set_rate = ccu_gate_set_rate,
128 .recalc_rate = ccu_gate_recalc_rate,
129 };
130