xref: /openbmc/linux/drivers/clk/tegra/clk-periph.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
4  */
5 
6 #include <linux/clk.h>
7 #include <linux/clk-provider.h>
8 #include <linux/export.h>
9 #include <linux/slab.h>
10 #include <linux/err.h>
11 
12 #include "clk.h"
13 
14 static u8 clk_periph_get_parent(struct clk_hw *hw)
15 {
16 	struct tegra_clk_periph *periph = to_clk_periph(hw);
17 	const struct clk_ops *mux_ops = periph->mux_ops;
18 	struct clk_hw *mux_hw = &periph->mux.hw;
19 
20 	__clk_hw_set_clk(mux_hw, hw);
21 
22 	return mux_ops->get_parent(mux_hw);
23 }
24 
25 static int clk_periph_set_parent(struct clk_hw *hw, u8 index)
26 {
27 	struct tegra_clk_periph *periph = to_clk_periph(hw);
28 	const struct clk_ops *mux_ops = periph->mux_ops;
29 	struct clk_hw *mux_hw = &periph->mux.hw;
30 
31 	__clk_hw_set_clk(mux_hw, hw);
32 
33 	return mux_ops->set_parent(mux_hw, index);
34 }
35 
36 static unsigned long clk_periph_recalc_rate(struct clk_hw *hw,
37 					    unsigned long parent_rate)
38 {
39 	struct tegra_clk_periph *periph = to_clk_periph(hw);
40 	const struct clk_ops *div_ops = periph->div_ops;
41 	struct clk_hw *div_hw = &periph->divider.hw;
42 
43 	__clk_hw_set_clk(div_hw, hw);
44 
45 	return div_ops->recalc_rate(div_hw, parent_rate);
46 }
47 
48 static long clk_periph_round_rate(struct clk_hw *hw, unsigned long rate,
49 				  unsigned long *prate)
50 {
51 	struct tegra_clk_periph *periph = to_clk_periph(hw);
52 	const struct clk_ops *div_ops = periph->div_ops;
53 	struct clk_hw *div_hw = &periph->divider.hw;
54 
55 	__clk_hw_set_clk(div_hw, hw);
56 
57 	return div_ops->round_rate(div_hw, rate, prate);
58 }
59 
60 static int clk_periph_set_rate(struct clk_hw *hw, unsigned long rate,
61 			       unsigned long parent_rate)
62 {
63 	struct tegra_clk_periph *periph = to_clk_periph(hw);
64 	const struct clk_ops *div_ops = periph->div_ops;
65 	struct clk_hw *div_hw = &periph->divider.hw;
66 
67 	__clk_hw_set_clk(div_hw, hw);
68 
69 	return div_ops->set_rate(div_hw, rate, parent_rate);
70 }
71 
72 static int clk_periph_is_enabled(struct clk_hw *hw)
73 {
74 	struct tegra_clk_periph *periph = to_clk_periph(hw);
75 	const struct clk_ops *gate_ops = periph->gate_ops;
76 	struct clk_hw *gate_hw = &periph->gate.hw;
77 
78 	__clk_hw_set_clk(gate_hw, hw);
79 
80 	return gate_ops->is_enabled(gate_hw);
81 }
82 
83 static int clk_periph_enable(struct clk_hw *hw)
84 {
85 	struct tegra_clk_periph *periph = to_clk_periph(hw);
86 	const struct clk_ops *gate_ops = periph->gate_ops;
87 	struct clk_hw *gate_hw = &periph->gate.hw;
88 
89 	__clk_hw_set_clk(gate_hw, hw);
90 
91 	return gate_ops->enable(gate_hw);
92 }
93 
94 static void clk_periph_disable(struct clk_hw *hw)
95 {
96 	struct tegra_clk_periph *periph = to_clk_periph(hw);
97 	const struct clk_ops *gate_ops = periph->gate_ops;
98 	struct clk_hw *gate_hw = &periph->gate.hw;
99 
100 	gate_ops->disable(gate_hw);
101 }
102 
103 static void clk_periph_disable_unused(struct clk_hw *hw)
104 {
105 	struct tegra_clk_periph *periph = to_clk_periph(hw);
106 	const struct clk_ops *gate_ops = periph->gate_ops;
107 	struct clk_hw *gate_hw = &periph->gate.hw;
108 
109 	gate_ops->disable_unused(gate_hw);
110 }
111 
112 static void clk_periph_restore_context(struct clk_hw *hw)
113 {
114 	struct tegra_clk_periph *periph = to_clk_periph(hw);
115 	const struct clk_ops *div_ops = periph->div_ops;
116 	struct clk_hw *div_hw = &periph->divider.hw;
117 	int parent_id;
118 
119 	parent_id = clk_hw_get_parent_index(hw);
120 	if (WARN_ON(parent_id < 0))
121 		return;
122 
123 	if (!(periph->gate.flags & TEGRA_PERIPH_NO_DIV))
124 		div_ops->restore_context(div_hw);
125 
126 	clk_periph_set_parent(hw, parent_id);
127 }
128 
129 const struct clk_ops tegra_clk_periph_ops = {
130 	.get_parent = clk_periph_get_parent,
131 	.set_parent = clk_periph_set_parent,
132 	.recalc_rate = clk_periph_recalc_rate,
133 	.round_rate = clk_periph_round_rate,
134 	.set_rate = clk_periph_set_rate,
135 	.is_enabled = clk_periph_is_enabled,
136 	.enable = clk_periph_enable,
137 	.disable = clk_periph_disable,
138 	.disable_unused = clk_periph_disable_unused,
139 	.restore_context = clk_periph_restore_context,
140 };
141 
142 static const struct clk_ops tegra_clk_periph_nodiv_ops = {
143 	.get_parent = clk_periph_get_parent,
144 	.set_parent = clk_periph_set_parent,
145 	.is_enabled = clk_periph_is_enabled,
146 	.enable = clk_periph_enable,
147 	.disable = clk_periph_disable,
148 	.disable_unused = clk_periph_disable_unused,
149 	.restore_context = clk_periph_restore_context,
150 };
151 
152 static const struct clk_ops tegra_clk_periph_no_gate_ops = {
153 	.get_parent = clk_periph_get_parent,
154 	.set_parent = clk_periph_set_parent,
155 	.recalc_rate = clk_periph_recalc_rate,
156 	.round_rate = clk_periph_round_rate,
157 	.set_rate = clk_periph_set_rate,
158 	.restore_context = clk_periph_restore_context,
159 };
160 
161 static struct clk *_tegra_clk_register_periph(const char *name,
162 			const char * const *parent_names, int num_parents,
163 			struct tegra_clk_periph *periph,
164 			void __iomem *clk_base, u32 offset,
165 			unsigned long flags)
166 {
167 	struct clk *clk;
168 	struct clk_init_data init;
169 	const struct tegra_clk_periph_regs *bank;
170 	bool div = !(periph->gate.flags & TEGRA_PERIPH_NO_DIV);
171 
172 	if (periph->gate.flags & TEGRA_PERIPH_NO_DIV) {
173 		flags |= CLK_SET_RATE_PARENT;
174 		init.ops = &tegra_clk_periph_nodiv_ops;
175 	} else if (periph->gate.flags & TEGRA_PERIPH_NO_GATE)
176 		init.ops = &tegra_clk_periph_no_gate_ops;
177 	else
178 		init.ops = &tegra_clk_periph_ops;
179 
180 	init.name = name;
181 	init.flags = flags;
182 	init.parent_names = parent_names;
183 	init.num_parents = num_parents;
184 
185 	bank = get_reg_bank(periph->gate.clk_num);
186 	if (!bank)
187 		return ERR_PTR(-EINVAL);
188 
189 	/* Data in .init is copied by clk_register(), so stack variable OK */
190 	periph->hw.init = &init;
191 	periph->magic = TEGRA_CLK_PERIPH_MAGIC;
192 	periph->mux.reg = clk_base + offset;
193 	periph->divider.reg = div ? (clk_base + offset) : NULL;
194 	periph->gate.clk_base = clk_base;
195 	periph->gate.regs = bank;
196 	periph->gate.enable_refcnt = periph_clk_enb_refcnt;
197 
198 	clk = clk_register(NULL, &periph->hw);
199 	if (IS_ERR(clk))
200 		return clk;
201 
202 	periph->mux.hw.clk = clk;
203 	periph->divider.hw.clk = div ? clk : NULL;
204 	periph->gate.hw.clk = clk;
205 
206 	return clk;
207 }
208 
209 struct clk *tegra_clk_register_periph(const char *name,
210 		const char * const *parent_names, int num_parents,
211 		struct tegra_clk_periph *periph, void __iomem *clk_base,
212 		u32 offset, unsigned long flags)
213 {
214 	return _tegra_clk_register_periph(name, parent_names, num_parents,
215 			periph, clk_base, offset, flags);
216 }
217 
218 struct clk *tegra_clk_register_periph_nodiv(const char *name,
219 		const char * const *parent_names, int num_parents,
220 		struct tegra_clk_periph *periph, void __iomem *clk_base,
221 		u32 offset)
222 {
223 	periph->gate.flags |= TEGRA_PERIPH_NO_DIV;
224 	return _tegra_clk_register_periph(name, parent_names, num_parents,
225 			periph, clk_base, offset, CLK_SET_RATE_PARENT);
226 }
227 
228 struct clk *tegra_clk_register_periph_data(void __iomem *clk_base,
229 					   struct tegra_periph_init_data *init)
230 {
231 	return _tegra_clk_register_periph(init->name, init->p.parent_names,
232 					  init->num_parents, &init->periph,
233 					  clk_base, init->offset, init->flags);
234 }
235