]>
Commit | Line | Data |
---|---|---|
b1a07b47 TK |
1 | /* |
2 | * TI clock autoidle support | |
3 | * | |
4 | * Copyright (C) 2013 Texas Instruments, Inc. | |
5 | * | |
6 | * Tero Kristo <t-kristo@ti.com> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | * | |
12 | * This program is distributed "as is" WITHOUT ANY WARRANTY of any | |
13 | * kind, whether express or implied; without even the implied warranty | |
14 | * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
16 | */ | |
17 | ||
18 | #include <linux/clk-provider.h> | |
19 | #include <linux/slab.h> | |
20 | #include <linux/io.h> | |
21 | #include <linux/of.h> | |
22 | #include <linux/of_address.h> | |
23 | #include <linux/clk/ti.h> | |
24 | ||
a3314e9c TK |
25 | #include "clock.h" |
26 | ||
b1a07b47 TK |
27 | struct clk_ti_autoidle { |
28 | void __iomem *reg; | |
29 | u8 shift; | |
30 | u8 flags; | |
31 | const char *name; | |
32 | struct list_head node; | |
33 | }; | |
34 | ||
35 | #define AUTOIDLE_LOW 0x1 | |
36 | ||
37 | static LIST_HEAD(autoidle_clks); | |
bf22bae7 | 38 | static LIST_HEAD(clk_hw_omap_clocks); |
b1a07b47 | 39 | |
bf22bae7 TK |
40 | /** |
41 | * omap2_clk_deny_idle - disable autoidle on an OMAP clock | |
42 | * @clk: struct clk * to disable autoidle for | |
43 | * | |
44 | * Disable autoidle on an OMAP clock. | |
45 | */ | |
46 | int omap2_clk_deny_idle(struct clk *clk) | |
47 | { | |
48 | struct clk_hw_omap *c; | |
49 | ||
bf22bae7 TK |
50 | c = to_clk_hw_omap(__clk_get_hw(clk)); |
51 | if (c->ops && c->ops->deny_idle) | |
52 | c->ops->deny_idle(c); | |
53 | return 0; | |
54 | } | |
55 | ||
56 | /** | |
57 | * omap2_clk_allow_idle - enable autoidle on an OMAP clock | |
58 | * @clk: struct clk * to enable autoidle for | |
59 | * | |
60 | * Enable autoidle on an OMAP clock. | |
61 | */ | |
62 | int omap2_clk_allow_idle(struct clk *clk) | |
63 | { | |
64 | struct clk_hw_omap *c; | |
65 | ||
bf22bae7 TK |
66 | c = to_clk_hw_omap(__clk_get_hw(clk)); |
67 | if (c->ops && c->ops->allow_idle) | |
68 | c->ops->allow_idle(c); | |
69 | return 0; | |
70 | } | |
71 | ||
72 | static void _allow_autoidle(struct clk_ti_autoidle *clk) | |
b1a07b47 TK |
73 | { |
74 | u32 val; | |
75 | ||
76 | val = ti_clk_ll_ops->clk_readl(clk->reg); | |
77 | ||
78 | if (clk->flags & AUTOIDLE_LOW) | |
79 | val &= ~(1 << clk->shift); | |
80 | else | |
81 | val |= (1 << clk->shift); | |
82 | ||
83 | ti_clk_ll_ops->clk_writel(val, clk->reg); | |
84 | } | |
85 | ||
bf22bae7 | 86 | static void _deny_autoidle(struct clk_ti_autoidle *clk) |
b1a07b47 TK |
87 | { |
88 | u32 val; | |
89 | ||
90 | val = ti_clk_ll_ops->clk_readl(clk->reg); | |
91 | ||
92 | if (clk->flags & AUTOIDLE_LOW) | |
93 | val |= (1 << clk->shift); | |
94 | else | |
95 | val &= ~(1 << clk->shift); | |
96 | ||
97 | ti_clk_ll_ops->clk_writel(val, clk->reg); | |
98 | } | |
99 | ||
100 | /** | |
bf22bae7 | 101 | * _clk_generic_allow_autoidle_all - enable autoidle for all clocks |
b1a07b47 TK |
102 | * |
103 | * Enables hardware autoidle for all registered DT clocks, which have | |
104 | * the feature. | |
105 | */ | |
bf22bae7 | 106 | static void _clk_generic_allow_autoidle_all(void) |
b1a07b47 TK |
107 | { |
108 | struct clk_ti_autoidle *c; | |
109 | ||
110 | list_for_each_entry(c, &autoidle_clks, node) | |
bf22bae7 | 111 | _allow_autoidle(c); |
b1a07b47 TK |
112 | } |
113 | ||
114 | /** | |
bf22bae7 | 115 | * _clk_generic_deny_autoidle_all - disable autoidle for all clocks |
b1a07b47 TK |
116 | * |
117 | * Disables hardware autoidle for all registered DT clocks, which have | |
118 | * the feature. | |
119 | */ | |
bf22bae7 | 120 | static void _clk_generic_deny_autoidle_all(void) |
b1a07b47 TK |
121 | { |
122 | struct clk_ti_autoidle *c; | |
123 | ||
124 | list_for_each_entry(c, &autoidle_clks, node) | |
bf22bae7 | 125 | _deny_autoidle(c); |
b1a07b47 TK |
126 | } |
127 | ||
128 | /** | |
129 | * of_ti_clk_autoidle_setup - sets up hardware autoidle for a clock | |
130 | * @node: pointer to the clock device node | |
131 | * | |
132 | * Checks if a clock has hardware autoidle support or not (check | |
133 | * for presence of 'ti,autoidle-shift' property in the device tree | |
134 | * node) and sets up the hardware autoidle feature for the clock | |
135 | * if available. If autoidle is available, the clock is also added | |
136 | * to the autoidle list for later processing. Returns 0 on success, | |
137 | * negative error value on failure. | |
138 | */ | |
139 | int __init of_ti_clk_autoidle_setup(struct device_node *node) | |
140 | { | |
141 | u32 shift; | |
142 | struct clk_ti_autoidle *clk; | |
143 | ||
144 | /* Check if this clock has autoidle support or not */ | |
145 | if (of_property_read_u32(node, "ti,autoidle-shift", &shift)) | |
146 | return 0; | |
147 | ||
148 | clk = kzalloc(sizeof(*clk), GFP_KERNEL); | |
149 | ||
150 | if (!clk) | |
151 | return -ENOMEM; | |
152 | ||
153 | clk->shift = shift; | |
154 | clk->name = node->name; | |
155 | clk->reg = ti_clk_get_reg_addr(node, 0); | |
156 | ||
c807dbed | 157 | if (IS_ERR(clk->reg)) { |
b1a07b47 TK |
158 | kfree(clk); |
159 | return -EINVAL; | |
160 | } | |
161 | ||
162 | if (of_property_read_bool(node, "ti,invert-autoidle-bit")) | |
163 | clk->flags |= AUTOIDLE_LOW; | |
164 | ||
165 | list_add(&clk->node, &autoidle_clks); | |
166 | ||
167 | return 0; | |
168 | } | |
bf22bae7 TK |
169 | |
170 | /** | |
171 | * omap2_init_clk_hw_omap_clocks - initialize an OMAP clock | |
a53ad8ef | 172 | * @hw: struct clk_hw * to initialize |
bf22bae7 TK |
173 | * |
174 | * Add an OMAP clock @clk to the internal list of OMAP clocks. Used | |
175 | * temporarily for autoidle handling, until this support can be | |
176 | * integrated into the common clock framework code in some way. No | |
177 | * return value. | |
178 | */ | |
a53ad8ef | 179 | void omap2_init_clk_hw_omap_clocks(struct clk_hw *hw) |
bf22bae7 TK |
180 | { |
181 | struct clk_hw_omap *c; | |
182 | ||
a53ad8ef | 183 | if (clk_hw_get_flags(hw) & CLK_IS_BASIC) |
bf22bae7 TK |
184 | return; |
185 | ||
a53ad8ef | 186 | c = to_clk_hw_omap(hw); |
bf22bae7 TK |
187 | list_add(&c->node, &clk_hw_omap_clocks); |
188 | } | |
189 | ||
190 | /** | |
191 | * omap2_clk_enable_autoidle_all - enable autoidle on all OMAP clocks that | |
192 | * support it | |
193 | * | |
194 | * Enable clock autoidle on all OMAP clocks that have allow_idle | |
195 | * function pointers associated with them. This function is intended | |
196 | * to be temporary until support for this is added to the common clock | |
197 | * code. Returns 0. | |
198 | */ | |
199 | int omap2_clk_enable_autoidle_all(void) | |
200 | { | |
201 | struct clk_hw_omap *c; | |
202 | ||
203 | list_for_each_entry(c, &clk_hw_omap_clocks, node) | |
204 | if (c->ops && c->ops->allow_idle) | |
205 | c->ops->allow_idle(c); | |
206 | ||
207 | _clk_generic_allow_autoidle_all(); | |
208 | ||
209 | return 0; | |
210 | } | |
211 | ||
212 | /** | |
213 | * omap2_clk_disable_autoidle_all - disable autoidle on all OMAP clocks that | |
214 | * support it | |
215 | * | |
216 | * Disable clock autoidle on all OMAP clocks that have allow_idle | |
217 | * function pointers associated with them. This function is intended | |
218 | * to be temporary until support for this is added to the common clock | |
219 | * code. Returns 0. | |
220 | */ | |
221 | int omap2_clk_disable_autoidle_all(void) | |
222 | { | |
223 | struct clk_hw_omap *c; | |
224 | ||
225 | list_for_each_entry(c, &clk_hw_omap_clocks, node) | |
226 | if (c->ops && c->ops->deny_idle) | |
227 | c->ops->deny_idle(c); | |
228 | ||
229 | _clk_generic_deny_autoidle_all(); | |
230 | ||
231 | return 0; | |
232 | } |