dma-mapping: consolidate dma_{alloc,free}_{attrs,coherent}
[linux-2.6-block.git] / drivers / clocksource / sh_mtu2.c
... / ...
CommitLineData
1/*
2 * SuperH Timer Support - MTU2
3 *
4 * Copyright (C) 2009 Magnus Damm
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16#include <linux/clk.h>
17#include <linux/clockchips.h>
18#include <linux/delay.h>
19#include <linux/err.h>
20#include <linux/init.h>
21#include <linux/interrupt.h>
22#include <linux/io.h>
23#include <linux/ioport.h>
24#include <linux/irq.h>
25#include <linux/module.h>
26#include <linux/of.h>
27#include <linux/platform_device.h>
28#include <linux/pm_domain.h>
29#include <linux/pm_runtime.h>
30#include <linux/sh_timer.h>
31#include <linux/slab.h>
32#include <linux/spinlock.h>
33
34struct sh_mtu2_device;
35
36struct sh_mtu2_channel {
37 struct sh_mtu2_device *mtu;
38 unsigned int index;
39
40 void __iomem *base;
41
42 struct clock_event_device ced;
43};
44
45struct sh_mtu2_device {
46 struct platform_device *pdev;
47
48 void __iomem *mapbase;
49 struct clk *clk;
50
51 raw_spinlock_t lock; /* Protect the shared registers */
52
53 struct sh_mtu2_channel *channels;
54 unsigned int num_channels;
55
56 bool has_clockevent;
57};
58
59#define TSTR -1 /* shared register */
60#define TCR 0 /* channel register */
61#define TMDR 1 /* channel register */
62#define TIOR 2 /* channel register */
63#define TIER 3 /* channel register */
64#define TSR 4 /* channel register */
65#define TCNT 5 /* channel register */
66#define TGR 6 /* channel register */
67
68#define TCR_CCLR_NONE (0 << 5)
69#define TCR_CCLR_TGRA (1 << 5)
70#define TCR_CCLR_TGRB (2 << 5)
71#define TCR_CCLR_SYNC (3 << 5)
72#define TCR_CCLR_TGRC (5 << 5)
73#define TCR_CCLR_TGRD (6 << 5)
74#define TCR_CCLR_MASK (7 << 5)
75#define TCR_CKEG_RISING (0 << 3)
76#define TCR_CKEG_FALLING (1 << 3)
77#define TCR_CKEG_BOTH (2 << 3)
78#define TCR_CKEG_MASK (3 << 3)
79/* Values 4 to 7 are channel-dependent */
80#define TCR_TPSC_P1 (0 << 0)
81#define TCR_TPSC_P4 (1 << 0)
82#define TCR_TPSC_P16 (2 << 0)
83#define TCR_TPSC_P64 (3 << 0)
84#define TCR_TPSC_CH0_TCLKA (4 << 0)
85#define TCR_TPSC_CH0_TCLKB (5 << 0)
86#define TCR_TPSC_CH0_TCLKC (6 << 0)
87#define TCR_TPSC_CH0_TCLKD (7 << 0)
88#define TCR_TPSC_CH1_TCLKA (4 << 0)
89#define TCR_TPSC_CH1_TCLKB (5 << 0)
90#define TCR_TPSC_CH1_P256 (6 << 0)
91#define TCR_TPSC_CH1_TCNT2 (7 << 0)
92#define TCR_TPSC_CH2_TCLKA (4 << 0)
93#define TCR_TPSC_CH2_TCLKB (5 << 0)
94#define TCR_TPSC_CH2_TCLKC (6 << 0)
95#define TCR_TPSC_CH2_P1024 (7 << 0)
96#define TCR_TPSC_CH34_P256 (4 << 0)
97#define TCR_TPSC_CH34_P1024 (5 << 0)
98#define TCR_TPSC_CH34_TCLKA (6 << 0)
99#define TCR_TPSC_CH34_TCLKB (7 << 0)
100#define TCR_TPSC_MASK (7 << 0)
101
102#define TMDR_BFE (1 << 6)
103#define TMDR_BFB (1 << 5)
104#define TMDR_BFA (1 << 4)
105#define TMDR_MD_NORMAL (0 << 0)
106#define TMDR_MD_PWM_1 (2 << 0)
107#define TMDR_MD_PWM_2 (3 << 0)
108#define TMDR_MD_PHASE_1 (4 << 0)
109#define TMDR_MD_PHASE_2 (5 << 0)
110#define TMDR_MD_PHASE_3 (6 << 0)
111#define TMDR_MD_PHASE_4 (7 << 0)
112#define TMDR_MD_PWM_SYNC (8 << 0)
113#define TMDR_MD_PWM_COMP_CREST (13 << 0)
114#define TMDR_MD_PWM_COMP_TROUGH (14 << 0)
115#define TMDR_MD_PWM_COMP_BOTH (15 << 0)
116#define TMDR_MD_MASK (15 << 0)
117
118#define TIOC_IOCH(n) ((n) << 4)
119#define TIOC_IOCL(n) ((n) << 0)
120#define TIOR_OC_RETAIN (0 << 0)
121#define TIOR_OC_0_CLEAR (1 << 0)
122#define TIOR_OC_0_SET (2 << 0)
123#define TIOR_OC_0_TOGGLE (3 << 0)
124#define TIOR_OC_1_CLEAR (5 << 0)
125#define TIOR_OC_1_SET (6 << 0)
126#define TIOR_OC_1_TOGGLE (7 << 0)
127#define TIOR_IC_RISING (8 << 0)
128#define TIOR_IC_FALLING (9 << 0)
129#define TIOR_IC_BOTH (10 << 0)
130#define TIOR_IC_TCNT (12 << 0)
131#define TIOR_MASK (15 << 0)
132
133#define TIER_TTGE (1 << 7)
134#define TIER_TTGE2 (1 << 6)
135#define TIER_TCIEU (1 << 5)
136#define TIER_TCIEV (1 << 4)
137#define TIER_TGIED (1 << 3)
138#define TIER_TGIEC (1 << 2)
139#define TIER_TGIEB (1 << 1)
140#define TIER_TGIEA (1 << 0)
141
142#define TSR_TCFD (1 << 7)
143#define TSR_TCFU (1 << 5)
144#define TSR_TCFV (1 << 4)
145#define TSR_TGFD (1 << 3)
146#define TSR_TGFC (1 << 2)
147#define TSR_TGFB (1 << 1)
148#define TSR_TGFA (1 << 0)
149
150static unsigned long mtu2_reg_offs[] = {
151 [TCR] = 0,
152 [TMDR] = 1,
153 [TIOR] = 2,
154 [TIER] = 4,
155 [TSR] = 5,
156 [TCNT] = 6,
157 [TGR] = 8,
158};
159
160static inline unsigned long sh_mtu2_read(struct sh_mtu2_channel *ch, int reg_nr)
161{
162 unsigned long offs;
163
164 if (reg_nr == TSTR)
165 return ioread8(ch->mtu->mapbase + 0x280);
166
167 offs = mtu2_reg_offs[reg_nr];
168
169 if ((reg_nr == TCNT) || (reg_nr == TGR))
170 return ioread16(ch->base + offs);
171 else
172 return ioread8(ch->base + offs);
173}
174
175static inline void sh_mtu2_write(struct sh_mtu2_channel *ch, int reg_nr,
176 unsigned long value)
177{
178 unsigned long offs;
179
180 if (reg_nr == TSTR)
181 return iowrite8(value, ch->mtu->mapbase + 0x280);
182
183 offs = mtu2_reg_offs[reg_nr];
184
185 if ((reg_nr == TCNT) || (reg_nr == TGR))
186 iowrite16(value, ch->base + offs);
187 else
188 iowrite8(value, ch->base + offs);
189}
190
191static void sh_mtu2_start_stop_ch(struct sh_mtu2_channel *ch, int start)
192{
193 unsigned long flags, value;
194
195 /* start stop register shared by multiple timer channels */
196 raw_spin_lock_irqsave(&ch->mtu->lock, flags);
197 value = sh_mtu2_read(ch, TSTR);
198
199 if (start)
200 value |= 1 << ch->index;
201 else
202 value &= ~(1 << ch->index);
203
204 sh_mtu2_write(ch, TSTR, value);
205 raw_spin_unlock_irqrestore(&ch->mtu->lock, flags);
206}
207
208static int sh_mtu2_enable(struct sh_mtu2_channel *ch)
209{
210 unsigned long periodic;
211 unsigned long rate;
212 int ret;
213
214 pm_runtime_get_sync(&ch->mtu->pdev->dev);
215 dev_pm_syscore_device(&ch->mtu->pdev->dev, true);
216
217 /* enable clock */
218 ret = clk_enable(ch->mtu->clk);
219 if (ret) {
220 dev_err(&ch->mtu->pdev->dev, "ch%u: cannot enable clock\n",
221 ch->index);
222 return ret;
223 }
224
225 /* make sure channel is disabled */
226 sh_mtu2_start_stop_ch(ch, 0);
227
228 rate = clk_get_rate(ch->mtu->clk) / 64;
229 periodic = (rate + HZ/2) / HZ;
230
231 /*
232 * "Periodic Counter Operation"
233 * Clear on TGRA compare match, divide clock by 64.
234 */
235 sh_mtu2_write(ch, TCR, TCR_CCLR_TGRA | TCR_TPSC_P64);
236 sh_mtu2_write(ch, TIOR, TIOC_IOCH(TIOR_OC_0_CLEAR) |
237 TIOC_IOCL(TIOR_OC_0_CLEAR));
238 sh_mtu2_write(ch, TGR, periodic);
239 sh_mtu2_write(ch, TCNT, 0);
240 sh_mtu2_write(ch, TMDR, TMDR_MD_NORMAL);
241 sh_mtu2_write(ch, TIER, TIER_TGIEA);
242
243 /* enable channel */
244 sh_mtu2_start_stop_ch(ch, 1);
245
246 return 0;
247}
248
249static void sh_mtu2_disable(struct sh_mtu2_channel *ch)
250{
251 /* disable channel */
252 sh_mtu2_start_stop_ch(ch, 0);
253
254 /* stop clock */
255 clk_disable(ch->mtu->clk);
256
257 dev_pm_syscore_device(&ch->mtu->pdev->dev, false);
258 pm_runtime_put(&ch->mtu->pdev->dev);
259}
260
261static irqreturn_t sh_mtu2_interrupt(int irq, void *dev_id)
262{
263 struct sh_mtu2_channel *ch = dev_id;
264
265 /* acknowledge interrupt */
266 sh_mtu2_read(ch, TSR);
267 sh_mtu2_write(ch, TSR, ~TSR_TGFA);
268
269 /* notify clockevent layer */
270 ch->ced.event_handler(&ch->ced);
271 return IRQ_HANDLED;
272}
273
274static struct sh_mtu2_channel *ced_to_sh_mtu2(struct clock_event_device *ced)
275{
276 return container_of(ced, struct sh_mtu2_channel, ced);
277}
278
279static int sh_mtu2_clock_event_shutdown(struct clock_event_device *ced)
280{
281 struct sh_mtu2_channel *ch = ced_to_sh_mtu2(ced);
282
283 sh_mtu2_disable(ch);
284 return 0;
285}
286
287static int sh_mtu2_clock_event_set_periodic(struct clock_event_device *ced)
288{
289 struct sh_mtu2_channel *ch = ced_to_sh_mtu2(ced);
290
291 if (clockevent_state_periodic(ced))
292 sh_mtu2_disable(ch);
293
294 dev_info(&ch->mtu->pdev->dev, "ch%u: used for periodic clock events\n",
295 ch->index);
296 sh_mtu2_enable(ch);
297 return 0;
298}
299
300static void sh_mtu2_clock_event_suspend(struct clock_event_device *ced)
301{
302 pm_genpd_syscore_poweroff(&ced_to_sh_mtu2(ced)->mtu->pdev->dev);
303}
304
305static void sh_mtu2_clock_event_resume(struct clock_event_device *ced)
306{
307 pm_genpd_syscore_poweron(&ced_to_sh_mtu2(ced)->mtu->pdev->dev);
308}
309
310static void sh_mtu2_register_clockevent(struct sh_mtu2_channel *ch,
311 const char *name)
312{
313 struct clock_event_device *ced = &ch->ced;
314
315 ced->name = name;
316 ced->features = CLOCK_EVT_FEAT_PERIODIC;
317 ced->rating = 200;
318 ced->cpumask = cpu_possible_mask;
319 ced->set_state_shutdown = sh_mtu2_clock_event_shutdown;
320 ced->set_state_periodic = sh_mtu2_clock_event_set_periodic;
321 ced->suspend = sh_mtu2_clock_event_suspend;
322 ced->resume = sh_mtu2_clock_event_resume;
323
324 dev_info(&ch->mtu->pdev->dev, "ch%u: used for clock events\n",
325 ch->index);
326 clockevents_register_device(ced);
327}
328
329static int sh_mtu2_register(struct sh_mtu2_channel *ch, const char *name)
330{
331 ch->mtu->has_clockevent = true;
332 sh_mtu2_register_clockevent(ch, name);
333
334 return 0;
335}
336
337static int sh_mtu2_setup_channel(struct sh_mtu2_channel *ch, unsigned int index,
338 struct sh_mtu2_device *mtu)
339{
340 static const unsigned int channel_offsets[] = {
341 0x300, 0x380, 0x000,
342 };
343 char name[6];
344 int irq;
345 int ret;
346
347 ch->mtu = mtu;
348
349 sprintf(name, "tgi%ua", index);
350 irq = platform_get_irq_byname(mtu->pdev, name);
351 if (irq < 0) {
352 /* Skip channels with no declared interrupt. */
353 return 0;
354 }
355
356 ret = request_irq(irq, sh_mtu2_interrupt,
357 IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
358 dev_name(&ch->mtu->pdev->dev), ch);
359 if (ret) {
360 dev_err(&ch->mtu->pdev->dev, "ch%u: failed to request irq %d\n",
361 index, irq);
362 return ret;
363 }
364
365 ch->base = mtu->mapbase + channel_offsets[index];
366 ch->index = index;
367
368 return sh_mtu2_register(ch, dev_name(&mtu->pdev->dev));
369}
370
371static int sh_mtu2_map_memory(struct sh_mtu2_device *mtu)
372{
373 struct resource *res;
374
375 res = platform_get_resource(mtu->pdev, IORESOURCE_MEM, 0);
376 if (!res) {
377 dev_err(&mtu->pdev->dev, "failed to get I/O memory\n");
378 return -ENXIO;
379 }
380
381 mtu->mapbase = ioremap_nocache(res->start, resource_size(res));
382 if (mtu->mapbase == NULL)
383 return -ENXIO;
384
385 return 0;
386}
387
388static int sh_mtu2_setup(struct sh_mtu2_device *mtu,
389 struct platform_device *pdev)
390{
391 unsigned int i;
392 int ret;
393
394 mtu->pdev = pdev;
395
396 raw_spin_lock_init(&mtu->lock);
397
398 /* Get hold of clock. */
399 mtu->clk = clk_get(&mtu->pdev->dev, "fck");
400 if (IS_ERR(mtu->clk)) {
401 dev_err(&mtu->pdev->dev, "cannot get clock\n");
402 return PTR_ERR(mtu->clk);
403 }
404
405 ret = clk_prepare(mtu->clk);
406 if (ret < 0)
407 goto err_clk_put;
408
409 /* Map the memory resource. */
410 ret = sh_mtu2_map_memory(mtu);
411 if (ret < 0) {
412 dev_err(&mtu->pdev->dev, "failed to remap I/O memory\n");
413 goto err_clk_unprepare;
414 }
415
416 /* Allocate and setup the channels. */
417 mtu->num_channels = 3;
418
419 mtu->channels = kzalloc(sizeof(*mtu->channels) * mtu->num_channels,
420 GFP_KERNEL);
421 if (mtu->channels == NULL) {
422 ret = -ENOMEM;
423 goto err_unmap;
424 }
425
426 for (i = 0; i < mtu->num_channels; ++i) {
427 ret = sh_mtu2_setup_channel(&mtu->channels[i], i, mtu);
428 if (ret < 0)
429 goto err_unmap;
430 }
431
432 platform_set_drvdata(pdev, mtu);
433
434 return 0;
435
436err_unmap:
437 kfree(mtu->channels);
438 iounmap(mtu->mapbase);
439err_clk_unprepare:
440 clk_unprepare(mtu->clk);
441err_clk_put:
442 clk_put(mtu->clk);
443 return ret;
444}
445
446static int sh_mtu2_probe(struct platform_device *pdev)
447{
448 struct sh_mtu2_device *mtu = platform_get_drvdata(pdev);
449 int ret;
450
451 if (!is_early_platform_device(pdev)) {
452 pm_runtime_set_active(&pdev->dev);
453 pm_runtime_enable(&pdev->dev);
454 }
455
456 if (mtu) {
457 dev_info(&pdev->dev, "kept as earlytimer\n");
458 goto out;
459 }
460
461 mtu = kzalloc(sizeof(*mtu), GFP_KERNEL);
462 if (mtu == NULL)
463 return -ENOMEM;
464
465 ret = sh_mtu2_setup(mtu, pdev);
466 if (ret) {
467 kfree(mtu);
468 pm_runtime_idle(&pdev->dev);
469 return ret;
470 }
471 if (is_early_platform_device(pdev))
472 return 0;
473
474 out:
475 if (mtu->has_clockevent)
476 pm_runtime_irq_safe(&pdev->dev);
477 else
478 pm_runtime_idle(&pdev->dev);
479
480 return 0;
481}
482
483static int sh_mtu2_remove(struct platform_device *pdev)
484{
485 return -EBUSY; /* cannot unregister clockevent */
486}
487
488static const struct platform_device_id sh_mtu2_id_table[] = {
489 { "sh-mtu2", 0 },
490 { },
491};
492MODULE_DEVICE_TABLE(platform, sh_mtu2_id_table);
493
494static const struct of_device_id sh_mtu2_of_table[] __maybe_unused = {
495 { .compatible = "renesas,mtu2" },
496 { }
497};
498MODULE_DEVICE_TABLE(of, sh_mtu2_of_table);
499
500static struct platform_driver sh_mtu2_device_driver = {
501 .probe = sh_mtu2_probe,
502 .remove = sh_mtu2_remove,
503 .driver = {
504 .name = "sh_mtu2",
505 .of_match_table = of_match_ptr(sh_mtu2_of_table),
506 },
507 .id_table = sh_mtu2_id_table,
508};
509
510static int __init sh_mtu2_init(void)
511{
512 return platform_driver_register(&sh_mtu2_device_driver);
513}
514
515static void __exit sh_mtu2_exit(void)
516{
517 platform_driver_unregister(&sh_mtu2_device_driver);
518}
519
520early_platform_init("earlytimer", &sh_mtu2_device_driver);
521subsys_initcall(sh_mtu2_init);
522module_exit(sh_mtu2_exit);
523
524MODULE_AUTHOR("Magnus Damm");
525MODULE_DESCRIPTION("SuperH MTU2 Timer Driver");
526MODULE_LICENSE("GPL v2");