1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2016 Maxime Ripard
4  * Maxime Ripard <maxime.ripard@free-electrons.com>
5  */
6 
7 #include <linux/clk-provider.h>
8 #include <linux/io.h>
9 
10 #include "ccu_gate.h"
11 
ccu_gate_helper_disable(struct ccu_common * common,u32 gate)12 void ccu_gate_helper_disable(struct ccu_common *common, u32 gate)
13 {
14 	unsigned long flags;
15 	u32 reg;
16 
17 	if (!gate)
18 		return;
19 
20 	spin_lock_irqsave(common->lock, flags);
21 
22 	reg = readl(common->base + common->reg);
23 	writel(reg & ~gate, common->base + common->reg);
24 
25 	spin_unlock_irqrestore(common->lock, flags);
26 }
27 
ccu_gate_disable(struct clk_hw * hw)28 static void ccu_gate_disable(struct clk_hw *hw)
29 {
30 	struct ccu_gate *cg = hw_to_ccu_gate(hw);
31 
32 	return ccu_gate_helper_disable(&cg->common, cg->enable);
33 }
34 
ccu_gate_helper_enable(struct ccu_common * common,u32 gate)35 int ccu_gate_helper_enable(struct ccu_common *common, u32 gate)
36 {
37 	unsigned long flags;
38 	u32 reg;
39 
40 	if (!gate)
41 		return 0;
42 
43 	spin_lock_irqsave(common->lock, flags);
44 
45 	reg = readl(common->base + common->reg);
46 	writel(reg | gate, common->base + common->reg);
47 
48 	spin_unlock_irqrestore(common->lock, flags);
49 
50 	return 0;
51 }
52 
ccu_gate_enable(struct clk_hw * hw)53 static int ccu_gate_enable(struct clk_hw *hw)
54 {
55 	struct ccu_gate *cg = hw_to_ccu_gate(hw);
56 
57 	return ccu_gate_helper_enable(&cg->common, cg->enable);
58 }
59 
ccu_gate_helper_is_enabled(struct ccu_common * common,u32 gate)60 int ccu_gate_helper_is_enabled(struct ccu_common *common, u32 gate)
61 {
62 	if (!gate)
63 		return 1;
64 
65 	return readl(common->base + common->reg) & gate;
66 }
67 
ccu_gate_is_enabled(struct clk_hw * hw)68 static int ccu_gate_is_enabled(struct clk_hw *hw)
69 {
70 	struct ccu_gate *cg = hw_to_ccu_gate(hw);
71 
72 	return ccu_gate_helper_is_enabled(&cg->common, cg->enable);
73 }
74 
ccu_gate_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)75 static unsigned long ccu_gate_recalc_rate(struct clk_hw *hw,
76 					  unsigned long parent_rate)
77 {
78 	struct ccu_gate *cg = hw_to_ccu_gate(hw);
79 	unsigned long rate = parent_rate;
80 
81 	if (cg->common.features & CCU_FEATURE_ALL_PREDIV)
82 		rate /= cg->common.prediv;
83 
84 	return rate;
85 }
86 
ccu_gate_round_rate(struct clk_hw * hw,unsigned long rate,unsigned long * prate)87 static long ccu_gate_round_rate(struct clk_hw *hw, unsigned long rate,
88 				unsigned long *prate)
89 {
90 	struct ccu_gate *cg = hw_to_ccu_gate(hw);
91 	int div = 1;
92 
93 	if (cg->common.features & CCU_FEATURE_ALL_PREDIV)
94 		div = cg->common.prediv;
95 
96 	if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) {
97 		unsigned long best_parent = rate;
98 
99 		if (cg->common.features & CCU_FEATURE_ALL_PREDIV)
100 			best_parent *= div;
101 		*prate = clk_hw_round_rate(clk_hw_get_parent(hw), best_parent);
102 	}
103 
104 	return *prate / div;
105 }
106 
ccu_gate_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)107 static int ccu_gate_set_rate(struct clk_hw *hw, unsigned long rate,
108 			     unsigned long parent_rate)
109 {
110 	/*
111 	 * We must report success but we can do so unconditionally because
112 	 * clk_factor_round_rate returns values that ensure this call is a
113 	 * nop.
114 	 */
115 
116 	return 0;
117 }
118 
119 const struct clk_ops ccu_gate_ops = {
120 	.disable	= ccu_gate_disable,
121 	.enable		= ccu_gate_enable,
122 	.is_enabled	= ccu_gate_is_enabled,
123 	.round_rate	= ccu_gate_round_rate,
124 	.set_rate	= ccu_gate_set_rate,
125 	.recalc_rate	= ccu_gate_recalc_rate,
126 };
127