2 * Copyright (c) 2013 Samsung Electronics Co., Ltd.
3 * Copyright (c) 2013 Linaro Ltd.
4 * Author: Thomas Abraham <thomas.ab@samsung.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 * This file includes utility functions to register clocks to common
11 * clock framework for Samsung platforms.
14 #include <linux/syscore_ops.h>
17 static DEFINE_SPINLOCK(lock);
18 static struct clk **clk_table;
19 static void __iomem *reg_base;
21 static struct clk_onecell_data clk_data;
24 void samsung_clk_save(void __iomem *base,
25 struct samsung_clk_reg_dump *rd,
26 unsigned int num_regs)
28 for (; num_regs > 0; --num_regs, ++rd)
29 rd->value = readl(base + rd->offset);
32 void samsung_clk_restore(void __iomem *base,
33 const struct samsung_clk_reg_dump *rd,
34 unsigned int num_regs)
36 for (; num_regs > 0; --num_regs, ++rd)
37 writel(rd->value, base + rd->offset);
40 struct samsung_clk_reg_dump *samsung_clk_alloc_reg_dump(
41 const unsigned long *rdump,
42 unsigned long nr_rdump)
44 struct samsung_clk_reg_dump *rd;
47 rd = kcalloc(nr_rdump, sizeof(*rd), GFP_KERNEL);
51 for (i = 0; i < nr_rdump; ++i)
52 rd[i].offset = rdump[i];
57 /* setup the essentials required to support clock lookup using ccf */
58 void __init samsung_clk_init(struct device_node *np, void __iomem *base,
59 unsigned long nr_clks)
63 clk_table = kzalloc(sizeof(struct clk *) * nr_clks, GFP_KERNEL);
65 panic("could not allocate clock lookup table\n");
71 clk_data.clks = clk_table;
72 clk_data.clk_num = nr_clks;
73 of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
77 /* add a clock instance to the clock lookup table used for dt based lookup */
78 void samsung_clk_add_lookup(struct clk *clk, unsigned int id)
84 /* register a list of aliases */
85 void __init samsung_clk_register_alias(struct samsung_clock_alias *list,
89 unsigned int idx, ret;
92 pr_err("%s: clock table missing\n", __func__);
96 for (idx = 0; idx < nr_clk; idx++, list++) {
98 pr_err("%s: clock id missing for index %d\n", __func__,
103 clk = clk_table[list->id];
105 pr_err("%s: failed to find clock %d\n", __func__,
110 ret = clk_register_clkdev(clk, list->alias, list->dev_name);
112 pr_err("%s: failed to register lookup %s\n",
113 __func__, list->alias);
117 /* register a list of fixed clocks */
118 void __init samsung_clk_register_fixed_rate(
119 struct samsung_fixed_rate_clock *list, unsigned int nr_clk)
122 unsigned int idx, ret;
124 for (idx = 0; idx < nr_clk; idx++, list++) {
125 clk = clk_register_fixed_rate(NULL, list->name,
126 list->parent_name, list->flags, list->fixed_rate);
128 pr_err("%s: failed to register clock %s\n", __func__,
133 samsung_clk_add_lookup(clk, list->id);
136 * Unconditionally add a clock lookup for the fixed rate clocks.
137 * There are not many of these on any of Samsung platforms.
139 ret = clk_register_clkdev(clk, list->name, NULL);
141 pr_err("%s: failed to register clock lookup for %s",
142 __func__, list->name);
146 /* register a list of fixed factor clocks */
147 void __init samsung_clk_register_fixed_factor(
148 struct samsung_fixed_factor_clock *list, unsigned int nr_clk)
153 for (idx = 0; idx < nr_clk; idx++, list++) {
154 clk = clk_register_fixed_factor(NULL, list->name,
155 list->parent_name, list->flags, list->mult, list->div);
157 pr_err("%s: failed to register clock %s\n", __func__,
162 samsung_clk_add_lookup(clk, list->id);
166 /* register a list of mux clocks */
167 void __init samsung_clk_register_mux(struct samsung_mux_clock *list,
171 unsigned int idx, ret;
173 for (idx = 0; idx < nr_clk; idx++, list++) {
174 clk = clk_register_mux(NULL, list->name, list->parent_names,
175 list->num_parents, list->flags, reg_base + list->offset,
176 list->shift, list->width, list->mux_flags, &lock);
178 pr_err("%s: failed to register clock %s\n", __func__,
183 samsung_clk_add_lookup(clk, list->id);
185 /* register a clock lookup only if a clock alias is specified */
187 ret = clk_register_clkdev(clk, list->alias,
190 pr_err("%s: failed to register lookup %s\n",
191 __func__, list->alias);
196 /* register a list of div clocks */
197 void __init samsung_clk_register_div(struct samsung_div_clock *list,
201 unsigned int idx, ret;
203 for (idx = 0; idx < nr_clk; idx++, list++) {
205 clk = clk_register_divider_table(NULL, list->name,
206 list->parent_name, list->flags,
207 reg_base + list->offset, list->shift,
208 list->width, list->div_flags,
211 clk = clk_register_divider(NULL, list->name,
212 list->parent_name, list->flags,
213 reg_base + list->offset, list->shift,
214 list->width, list->div_flags, &lock);
216 pr_err("%s: failed to register clock %s\n", __func__,
221 samsung_clk_add_lookup(clk, list->id);
223 /* register a clock lookup only if a clock alias is specified */
225 ret = clk_register_clkdev(clk, list->alias,
228 pr_err("%s: failed to register lookup %s\n",
229 __func__, list->alias);
234 /* register a list of gate clocks */
235 void __init samsung_clk_register_gate(struct samsung_gate_clock *list,
239 unsigned int idx, ret;
241 for (idx = 0; idx < nr_clk; idx++, list++) {
242 clk = clk_register_gate(NULL, list->name, list->parent_name,
243 list->flags, reg_base + list->offset,
244 list->bit_idx, list->gate_flags, &lock);
246 pr_err("%s: failed to register clock %s\n", __func__,
251 /* register a clock lookup only if a clock alias is specified */
253 ret = clk_register_clkdev(clk, list->alias,
256 pr_err("%s: failed to register lookup %s\n",
257 __func__, list->alias);
260 samsung_clk_add_lookup(clk, list->id);
265 * obtain the clock speed of all external fixed clock sources from device
266 * tree and register it
269 void __init samsung_clk_of_register_fixed_ext(
270 struct samsung_fixed_rate_clock *fixed_rate_clk,
271 unsigned int nr_fixed_rate_clk,
272 struct of_device_id *clk_matches)
274 const struct of_device_id *match;
275 struct device_node *np;
278 for_each_matching_node_and_match(np, clk_matches, &match) {
279 if (of_property_read_u32(np, "clock-frequency", &freq))
281 fixed_rate_clk[(u32)match->data].fixed_rate = freq;
283 samsung_clk_register_fixed_rate(fixed_rate_clk, nr_fixed_rate_clk);
287 /* utility function to get the rate of a specified clock */
288 unsigned long _get_rate(const char *clk_name)
292 clk = __clk_lookup(clk_name);
294 pr_err("%s: could not find clock %s\n", __func__, clk_name);
298 return clk_get_rate(clk);