xref: /openbmc/linux/drivers/clk/sunxi-ng/ccu_div.c (revision 07c7c6bf)
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 #include <linux/io.h>
13 
14 #include "ccu_gate.h"
15 #include "ccu_div.h"
16 
17 static unsigned long ccu_div_round_rate(struct ccu_mux_internal *mux,
18 					struct clk_hw *parent,
19 					unsigned long *parent_rate,
20 					unsigned long rate,
21 					void *data)
22 {
23 	struct ccu_div *cd = data;
24 
25 	if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
26 		rate *= cd->fixed_post_div;
27 
28 	rate = divider_round_rate_parent(&cd->common.hw, parent,
29 					 rate, parent_rate,
30 					 cd->div.table, cd->div.width,
31 					 cd->div.flags);
32 
33 	if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
34 		rate /= cd->fixed_post_div;
35 
36 	return rate;
37 }
38 
39 static void ccu_div_disable(struct clk_hw *hw)
40 {
41 	struct ccu_div *cd = hw_to_ccu_div(hw);
42 
43 	return ccu_gate_helper_disable(&cd->common, cd->enable);
44 }
45 
46 static int ccu_div_enable(struct clk_hw *hw)
47 {
48 	struct ccu_div *cd = hw_to_ccu_div(hw);
49 
50 	return ccu_gate_helper_enable(&cd->common, cd->enable);
51 }
52 
53 static int ccu_div_is_enabled(struct clk_hw *hw)
54 {
55 	struct ccu_div *cd = hw_to_ccu_div(hw);
56 
57 	return ccu_gate_helper_is_enabled(&cd->common, cd->enable);
58 }
59 
60 static unsigned long ccu_div_recalc_rate(struct clk_hw *hw,
61 					unsigned long parent_rate)
62 {
63 	struct ccu_div *cd = hw_to_ccu_div(hw);
64 	unsigned long val;
65 	u32 reg;
66 
67 	reg = readl(cd->common.base + cd->common.reg);
68 	val = reg >> cd->div.shift;
69 	val &= (1 << cd->div.width) - 1;
70 
71 	parent_rate = ccu_mux_helper_apply_prediv(&cd->common, &cd->mux, -1,
72 						  parent_rate);
73 
74 	val = divider_recalc_rate(hw, parent_rate, val, cd->div.table,
75 				  cd->div.flags, cd->div.width);
76 
77 	if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
78 		val /= cd->fixed_post_div;
79 
80 	return val;
81 }
82 
83 static int ccu_div_determine_rate(struct clk_hw *hw,
84 				struct clk_rate_request *req)
85 {
86 	struct ccu_div *cd = hw_to_ccu_div(hw);
87 
88 	return ccu_mux_helper_determine_rate(&cd->common, &cd->mux,
89 					     req, ccu_div_round_rate, cd);
90 }
91 
92 static int ccu_div_set_rate(struct clk_hw *hw, unsigned long rate,
93 			   unsigned long parent_rate)
94 {
95 	struct ccu_div *cd = hw_to_ccu_div(hw);
96 	unsigned long flags;
97 	unsigned long val;
98 	u32 reg;
99 
100 	parent_rate = ccu_mux_helper_apply_prediv(&cd->common, &cd->mux, -1,
101 						  parent_rate);
102 
103 	if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
104 		rate *= cd->fixed_post_div;
105 
106 	val = divider_get_val(rate, parent_rate, cd->div.table, cd->div.width,
107 			      cd->div.flags);
108 
109 	spin_lock_irqsave(cd->common.lock, flags);
110 
111 	reg = readl(cd->common.base + cd->common.reg);
112 	reg &= ~GENMASK(cd->div.width + cd->div.shift - 1, cd->div.shift);
113 
114 	writel(reg | (val << cd->div.shift),
115 	       cd->common.base + cd->common.reg);
116 
117 	spin_unlock_irqrestore(cd->common.lock, flags);
118 
119 	return 0;
120 }
121 
122 static u8 ccu_div_get_parent(struct clk_hw *hw)
123 {
124 	struct ccu_div *cd = hw_to_ccu_div(hw);
125 
126 	return ccu_mux_helper_get_parent(&cd->common, &cd->mux);
127 }
128 
129 static int ccu_div_set_parent(struct clk_hw *hw, u8 index)
130 {
131 	struct ccu_div *cd = hw_to_ccu_div(hw);
132 
133 	return ccu_mux_helper_set_parent(&cd->common, &cd->mux, index);
134 }
135 
136 const struct clk_ops ccu_div_ops = {
137 	.disable	= ccu_div_disable,
138 	.enable		= ccu_div_enable,
139 	.is_enabled	= ccu_div_is_enabled,
140 
141 	.get_parent	= ccu_div_get_parent,
142 	.set_parent	= ccu_div_set_parent,
143 
144 	.determine_rate	= ccu_div_determine_rate,
145 	.recalc_rate	= ccu_div_recalc_rate,
146 	.set_rate	= ccu_div_set_rate,
147 };
148