1 /*
2 * OMAP gate clock 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
25 #include "clock.h"
26
27 #define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw)
28
29 #undef pr_fmt
30 #define pr_fmt(fmt) "%s: " fmt, __func__
31
32 static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *clk);
33
34 static const struct clk_ops omap_gate_clkdm_clk_ops = {
35 .init = &omap2_init_clk_clkdm,
36 .enable = &omap2_clkops_enable_clkdm,
37 .disable = &omap2_clkops_disable_clkdm,
38 };
39
40 static const struct clk_ops omap_gate_clk_ops = {
41 .init = &omap2_init_clk_clkdm,
42 .enable = &omap2_dflt_clk_enable,
43 .disable = &omap2_dflt_clk_disable,
44 .is_enabled = &omap2_dflt_clk_is_enabled,
45 };
46
47 static const struct clk_ops omap_gate_clk_hsdiv_restore_ops = {
48 .init = &omap2_init_clk_clkdm,
49 .enable = &omap36xx_gate_clk_enable_with_hsdiv_restore,
50 .disable = &omap2_dflt_clk_disable,
51 .is_enabled = &omap2_dflt_clk_is_enabled,
52 };
53
54 /**
55 * omap36xx_gate_clk_enable_with_hsdiv_restore - enable clocks suffering
56 * from HSDivider PWRDN problem Implements Errata ID: i556.
57 * @clk: DPLL output struct clk
58 *
59 * 3630 only: dpll3_m3_ck, dpll4_m2_ck, dpll4_m3_ck, dpll4_m4_ck,
60 * dpll4_m5_ck & dpll4_m6_ck dividers gets loaded with reset
61 * valueafter their respective PWRDN bits are set. Any dummy write
62 * (Any other value different from the Read value) to the
63 * corresponding CM_CLKSEL register will refresh the dividers.
64 */
omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw * hw)65 static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *hw)
66 {
67 struct clk_divider *parent;
68 struct clk_hw *parent_hw;
69 u32 dummy_v, orig_v;
70 int ret;
71
72 /* Clear PWRDN bit of HSDIVIDER */
73 ret = omap2_dflt_clk_enable(hw);
74
75 /* Parent is the x2 node, get parent of parent for the m2 div */
76 parent_hw = clk_hw_get_parent(clk_hw_get_parent(hw));
77 parent = to_clk_divider(parent_hw);
78
79 /* Restore the dividers */
80 if (!ret) {
81 orig_v = ti_clk_ll_ops->clk_readl(parent->reg);
82 dummy_v = orig_v;
83
84 /* Write any other value different from the Read value */
85 dummy_v ^= (1 << parent->shift);
86 ti_clk_ll_ops->clk_writel(dummy_v, parent->reg);
87
88 /* Write the original divider */
89 ti_clk_ll_ops->clk_writel(orig_v, parent->reg);
90 }
91
92 return ret;
93 }
94
_register_gate(struct device * dev,const char * name,const char * parent_name,unsigned long flags,void __iomem * reg,u8 bit_idx,u8 clk_gate_flags,const struct clk_ops * ops,const struct clk_hw_omap_ops * hw_ops)95 static struct clk *_register_gate(struct device *dev, const char *name,
96 const char *parent_name, unsigned long flags,
97 void __iomem *reg, u8 bit_idx,
98 u8 clk_gate_flags, const struct clk_ops *ops,
99 const struct clk_hw_omap_ops *hw_ops)
100 {
101 struct clk_init_data init = { NULL };
102 struct clk_hw_omap *clk_hw;
103 struct clk *clk;
104
105 clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL);
106 if (!clk_hw)
107 return ERR_PTR(-ENOMEM);
108
109 clk_hw->hw.init = &init;
110
111 init.name = name;
112 init.ops = ops;
113
114 clk_hw->enable_reg = reg;
115 clk_hw->enable_bit = bit_idx;
116 clk_hw->ops = hw_ops;
117
118 clk_hw->flags = MEMMAP_ADDRESSING | clk_gate_flags;
119
120 init.parent_names = &parent_name;
121 init.num_parents = 1;
122
123 init.flags = flags;
124
125 clk = clk_register(NULL, &clk_hw->hw);
126
127 if (IS_ERR(clk))
128 kfree(clk_hw);
129
130 return clk;
131 }
132
133 #if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_ATAGS)
ti_clk_register_gate(struct ti_clk * setup)134 struct clk *ti_clk_register_gate(struct ti_clk *setup)
135 {
136 const struct clk_ops *ops = &omap_gate_clk_ops;
137 const struct clk_hw_omap_ops *hw_ops = NULL;
138 u32 reg;
139 struct clk_omap_reg *reg_setup;
140 u32 flags = 0;
141 u8 clk_gate_flags = 0;
142 struct ti_clk_gate *gate;
143
144 gate = setup->data;
145
146 if (gate->flags & CLKF_INTERFACE)
147 return ti_clk_register_interface(setup);
148
149 reg_setup = (struct clk_omap_reg *)®
150
151 if (gate->flags & CLKF_SET_RATE_PARENT)
152 flags |= CLK_SET_RATE_PARENT;
153
154 if (gate->flags & CLKF_SET_BIT_TO_DISABLE)
155 clk_gate_flags |= INVERT_ENABLE;
156
157 if (gate->flags & CLKF_HSDIV) {
158 ops = &omap_gate_clk_hsdiv_restore_ops;
159 hw_ops = &clkhwops_wait;
160 }
161
162 if (gate->flags & CLKF_DSS)
163 hw_ops = &clkhwops_omap3430es2_dss_usbhost_wait;
164
165 if (gate->flags & CLKF_WAIT)
166 hw_ops = &clkhwops_wait;
167
168 if (gate->flags & CLKF_CLKDM)
169 ops = &omap_gate_clkdm_clk_ops;
170
171 if (gate->flags & CLKF_AM35XX)
172 hw_ops = &clkhwops_am35xx_ipss_module_wait;
173
174 reg_setup->index = gate->module;
175 reg_setup->offset = gate->reg;
176
177 return _register_gate(NULL, setup->name, gate->parent, flags,
178 (void __iomem *)reg, gate->bit_shift,
179 clk_gate_flags, ops, hw_ops);
180 }
181
ti_clk_build_component_gate(struct ti_clk_gate * setup)182 struct clk_hw *ti_clk_build_component_gate(struct ti_clk_gate *setup)
183 {
184 struct clk_hw_omap *gate;
185 struct clk_omap_reg *reg;
186 const struct clk_hw_omap_ops *ops = &clkhwops_wait;
187
188 if (!setup)
189 return NULL;
190
191 gate = kzalloc(sizeof(*gate), GFP_KERNEL);
192 if (!gate)
193 return ERR_PTR(-ENOMEM);
194
195 reg = (struct clk_omap_reg *)&gate->enable_reg;
196 reg->index = setup->module;
197 reg->offset = setup->reg;
198
199 gate->enable_bit = setup->bit_shift;
200
201 if (setup->flags & CLKF_NO_WAIT)
202 ops = NULL;
203
204 if (setup->flags & CLKF_INTERFACE)
205 ops = &clkhwops_iclk_wait;
206
207 gate->ops = ops;
208 gate->flags = MEMMAP_ADDRESSING;
209
210 return &gate->hw;
211 }
212 #endif
213
_of_ti_gate_clk_setup(struct device_node * node,const struct clk_ops * ops,const struct clk_hw_omap_ops * hw_ops)214 static void __init _of_ti_gate_clk_setup(struct device_node *node,
215 const struct clk_ops *ops,
216 const struct clk_hw_omap_ops *hw_ops)
217 {
218 struct clk *clk;
219 const char *parent_name;
220 void __iomem *reg = NULL;
221 u8 enable_bit = 0;
222 u32 val;
223 u32 flags = 0;
224 u8 clk_gate_flags = 0;
225
226 if (ops != &omap_gate_clkdm_clk_ops) {
227 reg = ti_clk_get_reg_addr(node, 0);
228 if (IS_ERR(reg))
229 return;
230
231 if (!of_property_read_u32(node, "ti,bit-shift", &val))
232 enable_bit = val;
233 }
234
235 if (of_clk_get_parent_count(node) != 1) {
236 pr_err("%s must have 1 parent\n", node->name);
237 return;
238 }
239
240 parent_name = of_clk_get_parent_name(node, 0);
241
242 if (of_property_read_bool(node, "ti,set-rate-parent"))
243 flags |= CLK_SET_RATE_PARENT;
244
245 if (of_property_read_bool(node, "ti,set-bit-to-disable"))
246 clk_gate_flags |= INVERT_ENABLE;
247
248 clk = _register_gate(NULL, node->name, parent_name, flags, reg,
249 enable_bit, clk_gate_flags, ops, hw_ops);
250
251 if (!IS_ERR(clk))
252 of_clk_add_provider(node, of_clk_src_simple_get, clk);
253 }
254
255 static void __init
_of_ti_composite_gate_clk_setup(struct device_node * node,const struct clk_hw_omap_ops * hw_ops)256 _of_ti_composite_gate_clk_setup(struct device_node *node,
257 const struct clk_hw_omap_ops *hw_ops)
258 {
259 struct clk_hw_omap *gate;
260 u32 val = 0;
261
262 gate = kzalloc(sizeof(*gate), GFP_KERNEL);
263 if (!gate)
264 return;
265
266 gate->enable_reg = ti_clk_get_reg_addr(node, 0);
267 if (IS_ERR(gate->enable_reg))
268 goto cleanup;
269
270 of_property_read_u32(node, "ti,bit-shift", &val);
271
272 gate->enable_bit = val;
273 gate->ops = hw_ops;
274 gate->flags = MEMMAP_ADDRESSING;
275
276 if (!ti_clk_add_component(node, &gate->hw, CLK_COMPONENT_TYPE_GATE))
277 return;
278
279 cleanup:
280 kfree(gate);
281 }
282
283 static void __init
of_ti_composite_no_wait_gate_clk_setup(struct device_node * node)284 of_ti_composite_no_wait_gate_clk_setup(struct device_node *node)
285 {
286 _of_ti_composite_gate_clk_setup(node, NULL);
287 }
288 CLK_OF_DECLARE(ti_composite_no_wait_gate_clk, "ti,composite-no-wait-gate-clock",
289 of_ti_composite_no_wait_gate_clk_setup);
290
291 #if defined(CONFIG_ARCH_OMAP2) || defined(CONFIG_ARCH_OMAP3)
of_ti_composite_interface_clk_setup(struct device_node * node)292 static void __init of_ti_composite_interface_clk_setup(struct device_node *node)
293 {
294 _of_ti_composite_gate_clk_setup(node, &clkhwops_iclk_wait);
295 }
296 CLK_OF_DECLARE(ti_composite_interface_clk, "ti,composite-interface-clock",
297 of_ti_composite_interface_clk_setup);
298 #endif
299
of_ti_composite_gate_clk_setup(struct device_node * node)300 static void __init of_ti_composite_gate_clk_setup(struct device_node *node)
301 {
302 _of_ti_composite_gate_clk_setup(node, &clkhwops_wait);
303 }
304 CLK_OF_DECLARE(ti_composite_gate_clk, "ti,composite-gate-clock",
305 of_ti_composite_gate_clk_setup);
306
307
of_ti_clkdm_gate_clk_setup(struct device_node * node)308 static void __init of_ti_clkdm_gate_clk_setup(struct device_node *node)
309 {
310 _of_ti_gate_clk_setup(node, &omap_gate_clkdm_clk_ops, NULL);
311 }
312 CLK_OF_DECLARE(ti_clkdm_gate_clk, "ti,clkdm-gate-clock",
313 of_ti_clkdm_gate_clk_setup);
314
of_ti_hsdiv_gate_clk_setup(struct device_node * node)315 static void __init of_ti_hsdiv_gate_clk_setup(struct device_node *node)
316 {
317 _of_ti_gate_clk_setup(node, &omap_gate_clk_hsdiv_restore_ops,
318 &clkhwops_wait);
319 }
320 CLK_OF_DECLARE(ti_hsdiv_gate_clk, "ti,hsdiv-gate-clock",
321 of_ti_hsdiv_gate_clk_setup);
322
of_ti_gate_clk_setup(struct device_node * node)323 static void __init of_ti_gate_clk_setup(struct device_node *node)
324 {
325 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, NULL);
326 }
327 CLK_OF_DECLARE(ti_gate_clk, "ti,gate-clock", of_ti_gate_clk_setup);
328
of_ti_wait_gate_clk_setup(struct device_node * node)329 static void __init of_ti_wait_gate_clk_setup(struct device_node *node)
330 {
331 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, &clkhwops_wait);
332 }
333 CLK_OF_DECLARE(ti_wait_gate_clk, "ti,wait-gate-clock",
334 of_ti_wait_gate_clk_setup);
335
336 #ifdef CONFIG_ARCH_OMAP3
of_ti_am35xx_gate_clk_setup(struct device_node * node)337 static void __init of_ti_am35xx_gate_clk_setup(struct device_node *node)
338 {
339 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops,
340 &clkhwops_am35xx_ipss_module_wait);
341 }
342 CLK_OF_DECLARE(ti_am35xx_gate_clk, "ti,am35xx-gate-clock",
343 of_ti_am35xx_gate_clk_setup);
344
of_ti_dss_gate_clk_setup(struct device_node * node)345 static void __init of_ti_dss_gate_clk_setup(struct device_node *node)
346 {
347 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops,
348 &clkhwops_omap3430es2_dss_usbhost_wait);
349 }
350 CLK_OF_DECLARE(ti_dss_gate_clk, "ti,dss-gate-clock",
351 of_ti_dss_gate_clk_setup);
352 #endif
353