xref: /openbmc/linux/drivers/clk/sunxi-ng/ccu_div.c (revision c4e78957)
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 #include "ccu_div.h"
12 
13 static unsigned long ccu_div_round_rate(struct ccu_mux_internal *mux,
14 					struct clk_hw *parent,
15 					unsigned long *parent_rate,
16 					unsigned long rate,
17 					void *data)
18 {
19 	struct ccu_div *cd = data;
20 
21 	if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
22 		rate *= cd->fixed_post_div;
23 
24 	rate = divider_round_rate_parent(&cd->common.hw, parent,
25 					 rate, parent_rate,
26 					 cd->div.table, cd->div.width,
27 					 cd->div.flags);
28 
29 	if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
30 		rate /= cd->fixed_post_div;
31 
32 	return rate;
33 }
34 
35 static void ccu_div_disable(struct clk_hw *hw)
36 {
37 	struct ccu_div *cd = hw_to_ccu_div(hw);
38 
39 	return ccu_gate_helper_disable(&cd->common, cd->enable);
40 }
41 
42 static int ccu_div_enable(struct clk_hw *hw)
43 {
44 	struct ccu_div *cd = hw_to_ccu_div(hw);
45 
46 	return ccu_gate_helper_enable(&cd->common, cd->enable);
47 }
48 
49 static int ccu_div_is_enabled(struct clk_hw *hw)
50 {
51 	struct ccu_div *cd = hw_to_ccu_div(hw);
52 
53 	return ccu_gate_helper_is_enabled(&cd->common, cd->enable);
54 }
55 
56 static unsigned long ccu_div_recalc_rate(struct clk_hw *hw,
57 					unsigned long parent_rate)
58 {
59 	struct ccu_div *cd = hw_to_ccu_div(hw);
60 	unsigned long val;
61 	u32 reg;
62 
63 	reg = readl(cd->common.base + cd->common.reg);
64 	val = reg >> cd->div.shift;
65 	val &= (1 << cd->div.width) - 1;
66 
67 	parent_rate = ccu_mux_helper_apply_prediv(&cd->common, &cd->mux, -1,
68 						  parent_rate);
69 
70 	val = divider_recalc_rate(hw, parent_rate, val, cd->div.table,
71 				  cd->div.flags, cd->div.width);
72 
73 	if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
74 		val /= cd->fixed_post_div;
75 
76 	return val;
77 }
78 
79 static int ccu_div_determine_rate(struct clk_hw *hw,
80 				struct clk_rate_request *req)
81 {
82 	struct ccu_div *cd = hw_to_ccu_div(hw);
83 
84 	return ccu_mux_helper_determine_rate(&cd->common, &cd->mux,
85 					     req, ccu_div_round_rate, cd);
86 }
87 
88 static int ccu_div_set_rate(struct clk_hw *hw, unsigned long rate,
89 			   unsigned long parent_rate)
90 {
91 	struct ccu_div *cd = hw_to_ccu_div(hw);
92 	unsigned long flags;
93 	unsigned long val;
94 	u32 reg;
95 
96 	parent_rate = ccu_mux_helper_apply_prediv(&cd->common, &cd->mux, -1,
97 						  parent_rate);
98 
99 	if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
100 		rate *= cd->fixed_post_div;
101 
102 	val = divider_get_val(rate, parent_rate, cd->div.table, cd->div.width,
103 			      cd->div.flags);
104 
105 	spin_lock_irqsave(cd->common.lock, flags);
106 
107 	reg = readl(cd->common.base + cd->common.reg);
108 	reg &= ~GENMASK(cd->div.width + cd->div.shift - 1, cd->div.shift);
109 
110 	writel(reg | (val << cd->div.shift),
111 	       cd->common.base + cd->common.reg);
112 
113 	spin_unlock_irqrestore(cd->common.lock, flags);
114 
115 	return 0;
116 }
117 
118 static u8 ccu_div_get_parent(struct clk_hw *hw)
119 {
120 	struct ccu_div *cd = hw_to_ccu_div(hw);
121 
122 	return ccu_mux_helper_get_parent(&cd->common, &cd->mux);
123 }
124 
125 static int ccu_div_set_parent(struct clk_hw *hw, u8 index)
126 {
127 	struct ccu_div *cd = hw_to_ccu_div(hw);
128 
129 	return ccu_mux_helper_set_parent(&cd->common, &cd->mux, index);
130 }
131 
132 const struct clk_ops ccu_div_ops = {
133 	.disable	= ccu_div_disable,
134 	.enable		= ccu_div_enable,
135 	.is_enabled	= ccu_div_is_enabled,
136 
137 	.get_parent	= ccu_div_get_parent,
138 	.set_parent	= ccu_div_set_parent,
139 
140 	.determine_rate	= ccu_div_determine_rate,
141 	.recalc_rate	= ccu_div_recalc_rate,
142 	.set_rate	= ccu_div_set_rate,
143 };
144 EXPORT_SYMBOL_NS_GPL(ccu_div_ops, SUNXI_CCU);
145