1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2013 Heiko Stuebner <heiko@sntech.de>
4 *
5 * Common Clock Framework support for s3c24xx external clock output.
6 */
7
8 #include <linux/clkdev.h>
9 #include <linux/slab.h>
10 #include <linux/clk.h>
11 #include <linux/clk-provider.h>
12 #include <linux/io.h>
13 #include <linux/platform_device.h>
14 #include <linux/platform_data/clk-s3c2410.h>
15 #include <linux/module.h>
16 #include "clk.h"
17
18 #define MUX_DCLK0 0
19 #define MUX_DCLK1 1
20 #define DIV_DCLK0 2
21 #define DIV_DCLK1 3
22 #define GATE_DCLK0 4
23 #define GATE_DCLK1 5
24 #define MUX_CLKOUT0 6
25 #define MUX_CLKOUT1 7
26 #define DCLK_MAX_CLKS (MUX_CLKOUT1 + 1)
27
28 enum supported_socs {
29 S3C2410,
30 S3C2412,
31 S3C2440,
32 S3C2443,
33 };
34
35 struct s3c24xx_dclk_drv_data {
36 const char **clkout0_parent_names;
37 int clkout0_num_parents;
38 const char **clkout1_parent_names;
39 int clkout1_num_parents;
40 const char **mux_parent_names;
41 int mux_num_parents;
42 };
43
44 /*
45 * Clock for output-parent selection in misccr
46 */
47
48 struct s3c24xx_clkout {
49 struct clk_hw hw;
50 u32 mask;
51 u8 shift;
52 unsigned int (*modify_misccr)(unsigned int clr, unsigned int chg);
53 };
54
55 #define to_s3c24xx_clkout(_hw) container_of(_hw, struct s3c24xx_clkout, hw)
56
s3c24xx_clkout_get_parent(struct clk_hw * hw)57 static u8 s3c24xx_clkout_get_parent(struct clk_hw *hw)
58 {
59 struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
60 int num_parents = clk_hw_get_num_parents(hw);
61 u32 val;
62
63 val = clkout->modify_misccr(0, 0) >> clkout->shift;
64 val >>= clkout->shift;
65 val &= clkout->mask;
66
67 if (val >= num_parents)
68 return -EINVAL;
69
70 return val;
71 }
72
s3c24xx_clkout_set_parent(struct clk_hw * hw,u8 index)73 static int s3c24xx_clkout_set_parent(struct clk_hw *hw, u8 index)
74 {
75 struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
76
77 clkout->modify_misccr((clkout->mask << clkout->shift),
78 (index << clkout->shift));
79
80 return 0;
81 }
82
83 static const struct clk_ops s3c24xx_clkout_ops = {
84 .get_parent = s3c24xx_clkout_get_parent,
85 .set_parent = s3c24xx_clkout_set_parent,
86 .determine_rate = __clk_mux_determine_rate,
87 };
88
s3c24xx_register_clkout(struct device * dev,const char * name,const char ** parent_names,u8 num_parents,u8 shift,u32 mask)89 static struct clk_hw *s3c24xx_register_clkout(struct device *dev,
90 const char *name, const char **parent_names, u8 num_parents,
91 u8 shift, u32 mask)
92 {
93 struct s3c2410_clk_platform_data *pdata = dev_get_platdata(dev);
94 struct s3c24xx_clkout *clkout;
95 struct clk_init_data init;
96 int ret;
97
98 if (!pdata)
99 return ERR_PTR(-EINVAL);
100
101 /* allocate the clkout */
102 clkout = kzalloc(sizeof(*clkout), GFP_KERNEL);
103 if (!clkout)
104 return ERR_PTR(-ENOMEM);
105
106 init.name = name;
107 init.ops = &s3c24xx_clkout_ops;
108 init.flags = 0;
109 init.parent_names = parent_names;
110 init.num_parents = num_parents;
111
112 clkout->shift = shift;
113 clkout->mask = mask;
114 clkout->hw.init = &init;
115 clkout->modify_misccr = pdata->modify_misccr;
116
117 ret = clk_hw_register(dev, &clkout->hw);
118 if (ret)
119 return ERR_PTR(ret);
120
121 return &clkout->hw;
122 }
123
124 /*
125 * dclk and clkout init
126 */
127
128 struct s3c24xx_dclk {
129 struct device *dev;
130 void __iomem *base;
131 struct notifier_block dclk0_div_change_nb;
132 struct notifier_block dclk1_div_change_nb;
133 spinlock_t dclk_lock;
134 unsigned long reg_save;
135 /* clk_data must be the last entry in the structure */
136 struct clk_hw_onecell_data clk_data;
137 };
138
139 #define to_s3c24xx_dclk0(x) \
140 container_of(x, struct s3c24xx_dclk, dclk0_div_change_nb)
141
142 #define to_s3c24xx_dclk1(x) \
143 container_of(x, struct s3c24xx_dclk, dclk1_div_change_nb)
144
145 static const char *dclk_s3c2410_p[] = { "pclk", "uclk" };
146 static const char *clkout0_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
147 "gate_dclk0" };
148 static const char *clkout1_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
149 "gate_dclk1" };
150
151 static const char *clkout0_s3c2412_p[] = { "mpll", "upll", "rtc_clkout",
152 "hclk", "pclk", "gate_dclk0" };
153 static const char *clkout1_s3c2412_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
154 "gate_dclk1" };
155
156 static const char *clkout0_s3c2440_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
157 "gate_dclk0" };
158 static const char *clkout1_s3c2440_p[] = { "mpll", "upll", "rtc_clkout",
159 "hclk", "pclk", "gate_dclk1" };
160
161 static const char *dclk_s3c2443_p[] = { "pclk", "epll" };
162 static const char *clkout0_s3c2443_p[] = { "xti", "epll", "armclk", "hclk", "pclk",
163 "gate_dclk0" };
164 static const char *clkout1_s3c2443_p[] = { "dummy", "epll", "rtc_clkout",
165 "hclk", "pclk", "gate_dclk1" };
166
167 #define DCLKCON_DCLK_DIV_MASK 0xf
168 #define DCLKCON_DCLK0_DIV_SHIFT 4
169 #define DCLKCON_DCLK0_CMP_SHIFT 8
170 #define DCLKCON_DCLK1_DIV_SHIFT 20
171 #define DCLKCON_DCLK1_CMP_SHIFT 24
172
s3c24xx_dclk_update_cmp(struct s3c24xx_dclk * s3c24xx_dclk,int div_shift,int cmp_shift)173 static void s3c24xx_dclk_update_cmp(struct s3c24xx_dclk *s3c24xx_dclk,
174 int div_shift, int cmp_shift)
175 {
176 unsigned long flags = 0;
177 u32 dclk_con, div, cmp;
178
179 spin_lock_irqsave(&s3c24xx_dclk->dclk_lock, flags);
180
181 dclk_con = readl_relaxed(s3c24xx_dclk->base);
182
183 div = ((dclk_con >> div_shift) & DCLKCON_DCLK_DIV_MASK) + 1;
184 cmp = ((div + 1) / 2) - 1;
185
186 dclk_con &= ~(DCLKCON_DCLK_DIV_MASK << cmp_shift);
187 dclk_con |= (cmp << cmp_shift);
188
189 writel_relaxed(dclk_con, s3c24xx_dclk->base);
190
191 spin_unlock_irqrestore(&s3c24xx_dclk->dclk_lock, flags);
192 }
193
s3c24xx_dclk0_div_notify(struct notifier_block * nb,unsigned long event,void * data)194 static int s3c24xx_dclk0_div_notify(struct notifier_block *nb,
195 unsigned long event, void *data)
196 {
197 struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk0(nb);
198
199 if (event == POST_RATE_CHANGE) {
200 s3c24xx_dclk_update_cmp(s3c24xx_dclk,
201 DCLKCON_DCLK0_DIV_SHIFT, DCLKCON_DCLK0_CMP_SHIFT);
202 }
203
204 return NOTIFY_DONE;
205 }
206
s3c24xx_dclk1_div_notify(struct notifier_block * nb,unsigned long event,void * data)207 static int s3c24xx_dclk1_div_notify(struct notifier_block *nb,
208 unsigned long event, void *data)
209 {
210 struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk1(nb);
211
212 if (event == POST_RATE_CHANGE) {
213 s3c24xx_dclk_update_cmp(s3c24xx_dclk,
214 DCLKCON_DCLK1_DIV_SHIFT, DCLKCON_DCLK1_CMP_SHIFT);
215 }
216
217 return NOTIFY_DONE;
218 }
219
220 #ifdef CONFIG_PM_SLEEP
s3c24xx_dclk_suspend(struct device * dev)221 static int s3c24xx_dclk_suspend(struct device *dev)
222 {
223 struct s3c24xx_dclk *s3c24xx_dclk = dev_get_drvdata(dev);
224
225 s3c24xx_dclk->reg_save = readl_relaxed(s3c24xx_dclk->base);
226 return 0;
227 }
228
s3c24xx_dclk_resume(struct device * dev)229 static int s3c24xx_dclk_resume(struct device *dev)
230 {
231 struct s3c24xx_dclk *s3c24xx_dclk = dev_get_drvdata(dev);
232
233 writel_relaxed(s3c24xx_dclk->reg_save, s3c24xx_dclk->base);
234 return 0;
235 }
236 #endif
237
238 static SIMPLE_DEV_PM_OPS(s3c24xx_dclk_pm_ops,
239 s3c24xx_dclk_suspend, s3c24xx_dclk_resume);
240
s3c24xx_dclk_probe(struct platform_device * pdev)241 static int s3c24xx_dclk_probe(struct platform_device *pdev)
242 {
243 struct s3c24xx_dclk *s3c24xx_dclk;
244 struct s3c24xx_dclk_drv_data *dclk_variant;
245 struct clk_hw **clk_table;
246 int ret, i;
247
248 s3c24xx_dclk = devm_kzalloc(&pdev->dev,
249 struct_size(s3c24xx_dclk, clk_data.hws,
250 DCLK_MAX_CLKS),
251 GFP_KERNEL);
252 if (!s3c24xx_dclk)
253 return -ENOMEM;
254
255 clk_table = s3c24xx_dclk->clk_data.hws;
256
257 s3c24xx_dclk->dev = &pdev->dev;
258 s3c24xx_dclk->clk_data.num = DCLK_MAX_CLKS;
259 platform_set_drvdata(pdev, s3c24xx_dclk);
260 spin_lock_init(&s3c24xx_dclk->dclk_lock);
261
262 s3c24xx_dclk->base = devm_platform_ioremap_resource(pdev, 0);
263 if (IS_ERR(s3c24xx_dclk->base))
264 return PTR_ERR(s3c24xx_dclk->base);
265
266 dclk_variant = (struct s3c24xx_dclk_drv_data *)
267 platform_get_device_id(pdev)->driver_data;
268
269
270 clk_table[MUX_DCLK0] = clk_hw_register_mux(&pdev->dev, "mux_dclk0",
271 dclk_variant->mux_parent_names,
272 dclk_variant->mux_num_parents, 0,
273 s3c24xx_dclk->base, 1, 1, 0,
274 &s3c24xx_dclk->dclk_lock);
275 clk_table[MUX_DCLK1] = clk_hw_register_mux(&pdev->dev, "mux_dclk1",
276 dclk_variant->mux_parent_names,
277 dclk_variant->mux_num_parents, 0,
278 s3c24xx_dclk->base, 17, 1, 0,
279 &s3c24xx_dclk->dclk_lock);
280
281 clk_table[DIV_DCLK0] = clk_hw_register_divider(&pdev->dev, "div_dclk0",
282 "mux_dclk0", 0, s3c24xx_dclk->base,
283 4, 4, 0, &s3c24xx_dclk->dclk_lock);
284 clk_table[DIV_DCLK1] = clk_hw_register_divider(&pdev->dev, "div_dclk1",
285 "mux_dclk1", 0, s3c24xx_dclk->base,
286 20, 4, 0, &s3c24xx_dclk->dclk_lock);
287
288 clk_table[GATE_DCLK0] = clk_hw_register_gate(&pdev->dev, "gate_dclk0",
289 "div_dclk0", CLK_SET_RATE_PARENT,
290 s3c24xx_dclk->base, 0, 0,
291 &s3c24xx_dclk->dclk_lock);
292 clk_table[GATE_DCLK1] = clk_hw_register_gate(&pdev->dev, "gate_dclk1",
293 "div_dclk1", CLK_SET_RATE_PARENT,
294 s3c24xx_dclk->base, 16, 0,
295 &s3c24xx_dclk->dclk_lock);
296
297 clk_table[MUX_CLKOUT0] = s3c24xx_register_clkout(&pdev->dev,
298 "clkout0", dclk_variant->clkout0_parent_names,
299 dclk_variant->clkout0_num_parents, 4, 7);
300 clk_table[MUX_CLKOUT1] = s3c24xx_register_clkout(&pdev->dev,
301 "clkout1", dclk_variant->clkout1_parent_names,
302 dclk_variant->clkout1_num_parents, 8, 7);
303
304 for (i = 0; i < DCLK_MAX_CLKS; i++)
305 if (IS_ERR(clk_table[i])) {
306 dev_err(&pdev->dev, "clock %d failed to register\n", i);
307 ret = PTR_ERR(clk_table[i]);
308 goto err_clk_register;
309 }
310
311 ret = clk_hw_register_clkdev(clk_table[MUX_DCLK0], "dclk0", NULL);
312 if (!ret)
313 ret = clk_hw_register_clkdev(clk_table[MUX_DCLK1], "dclk1",
314 NULL);
315 if (!ret)
316 ret = clk_hw_register_clkdev(clk_table[MUX_CLKOUT0],
317 "clkout0", NULL);
318 if (!ret)
319 ret = clk_hw_register_clkdev(clk_table[MUX_CLKOUT1],
320 "clkout1", NULL);
321 if (ret) {
322 dev_err(&pdev->dev, "failed to register aliases, %d\n", ret);
323 goto err_clk_register;
324 }
325
326 s3c24xx_dclk->dclk0_div_change_nb.notifier_call =
327 s3c24xx_dclk0_div_notify;
328
329 s3c24xx_dclk->dclk1_div_change_nb.notifier_call =
330 s3c24xx_dclk1_div_notify;
331
332 ret = clk_notifier_register(clk_table[DIV_DCLK0]->clk,
333 &s3c24xx_dclk->dclk0_div_change_nb);
334 if (ret)
335 goto err_clk_register;
336
337 ret = clk_notifier_register(clk_table[DIV_DCLK1]->clk,
338 &s3c24xx_dclk->dclk1_div_change_nb);
339 if (ret)
340 goto err_dclk_notify;
341
342 return 0;
343
344 err_dclk_notify:
345 clk_notifier_unregister(clk_table[DIV_DCLK0]->clk,
346 &s3c24xx_dclk->dclk0_div_change_nb);
347 err_clk_register:
348 for (i = 0; i < DCLK_MAX_CLKS; i++)
349 if (clk_table[i] && !IS_ERR(clk_table[i]))
350 clk_hw_unregister(clk_table[i]);
351
352 return ret;
353 }
354
s3c24xx_dclk_remove(struct platform_device * pdev)355 static int s3c24xx_dclk_remove(struct platform_device *pdev)
356 {
357 struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
358 struct clk_hw **clk_table = s3c24xx_dclk->clk_data.hws;
359 int i;
360
361 clk_notifier_unregister(clk_table[DIV_DCLK1]->clk,
362 &s3c24xx_dclk->dclk1_div_change_nb);
363 clk_notifier_unregister(clk_table[DIV_DCLK0]->clk,
364 &s3c24xx_dclk->dclk0_div_change_nb);
365
366 for (i = 0; i < DCLK_MAX_CLKS; i++)
367 clk_hw_unregister(clk_table[i]);
368
369 return 0;
370 }
371
372 static struct s3c24xx_dclk_drv_data dclk_variants[] = {
373 [S3C2410] = {
374 .clkout0_parent_names = clkout0_s3c2410_p,
375 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2410_p),
376 .clkout1_parent_names = clkout1_s3c2410_p,
377 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2410_p),
378 .mux_parent_names = dclk_s3c2410_p,
379 .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
380 },
381 [S3C2412] = {
382 .clkout0_parent_names = clkout0_s3c2412_p,
383 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2412_p),
384 .clkout1_parent_names = clkout1_s3c2412_p,
385 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2412_p),
386 .mux_parent_names = dclk_s3c2410_p,
387 .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
388 },
389 [S3C2440] = {
390 .clkout0_parent_names = clkout0_s3c2440_p,
391 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2440_p),
392 .clkout1_parent_names = clkout1_s3c2440_p,
393 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2440_p),
394 .mux_parent_names = dclk_s3c2410_p,
395 .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
396 },
397 [S3C2443] = {
398 .clkout0_parent_names = clkout0_s3c2443_p,
399 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2443_p),
400 .clkout1_parent_names = clkout1_s3c2443_p,
401 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2443_p),
402 .mux_parent_names = dclk_s3c2443_p,
403 .mux_num_parents = ARRAY_SIZE(dclk_s3c2443_p),
404 },
405 };
406
407 static const struct platform_device_id s3c24xx_dclk_driver_ids[] = {
408 {
409 .name = "s3c2410-dclk",
410 .driver_data = (kernel_ulong_t)&dclk_variants[S3C2410],
411 }, {
412 .name = "s3c2412-dclk",
413 .driver_data = (kernel_ulong_t)&dclk_variants[S3C2412],
414 }, {
415 .name = "s3c2440-dclk",
416 .driver_data = (kernel_ulong_t)&dclk_variants[S3C2440],
417 }, {
418 .name = "s3c2443-dclk",
419 .driver_data = (kernel_ulong_t)&dclk_variants[S3C2443],
420 },
421 { }
422 };
423
424 MODULE_DEVICE_TABLE(platform, s3c24xx_dclk_driver_ids);
425
426 static struct platform_driver s3c24xx_dclk_driver = {
427 .driver = {
428 .name = "s3c24xx-dclk",
429 .pm = &s3c24xx_dclk_pm_ops,
430 .suppress_bind_attrs = true,
431 },
432 .probe = s3c24xx_dclk_probe,
433 .remove = s3c24xx_dclk_remove,
434 .id_table = s3c24xx_dclk_driver_ids,
435 };
436 module_platform_driver(s3c24xx_dclk_driver);
437
438 MODULE_LICENSE("GPL v2");
439 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
440 MODULE_DESCRIPTION("Driver for the S3C24XX external clock outputs");
441