aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/devfreq/tegra-devfreq.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/devfreq/tegra-devfreq.c')
-rw-r--r--drivers/devfreq/tegra-devfreq.c718
1 files changed, 718 insertions, 0 deletions
diff --git a/drivers/devfreq/tegra-devfreq.c b/drivers/devfreq/tegra-devfreq.c
new file mode 100644
index 000000000000..34790961af5a
--- /dev/null
+++ b/drivers/devfreq/tegra-devfreq.c
@@ -0,0 +1,718 @@
1/*
2 * A devfreq driver for NVIDIA Tegra SoCs
3 *
4 * Copyright (c) 2014 NVIDIA CORPORATION. All rights reserved.
5 * Copyright (C) 2014 Google, Inc
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms and conditions of the GNU General Public License,
9 * version 2, as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 *
19 */
20
21#include <linux/clk.h>
22#include <linux/cpufreq.h>
23#include <linux/devfreq.h>
24#include <linux/interrupt.h>
25#include <linux/io.h>
26#include <linux/module.h>
27#include <linux/platform_device.h>
28#include <linux/pm_opp.h>
29#include <linux/reset.h>
30
31#include "governor.h"
32
33#define ACTMON_GLB_STATUS 0x0
34#define ACTMON_GLB_PERIOD_CTRL 0x4
35
36#define ACTMON_DEV_CTRL 0x0
37#define ACTMON_DEV_CTRL_K_VAL_SHIFT 10
38#define ACTMON_DEV_CTRL_ENB_PERIODIC BIT(18)
39#define ACTMON_DEV_CTRL_AVG_BELOW_WMARK_EN BIT(20)
40#define ACTMON_DEV_CTRL_AVG_ABOVE_WMARK_EN BIT(21)
41#define ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_NUM_SHIFT 23
42#define ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_NUM_SHIFT 26
43#define ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN BIT(29)
44#define ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN BIT(30)
45#define ACTMON_DEV_CTRL_ENB BIT(31)
46
47#define ACTMON_DEV_UPPER_WMARK 0x4
48#define ACTMON_DEV_LOWER_WMARK 0x8
49#define ACTMON_DEV_INIT_AVG 0xc
50#define ACTMON_DEV_AVG_UPPER_WMARK 0x10
51#define ACTMON_DEV_AVG_LOWER_WMARK 0x14
52#define ACTMON_DEV_COUNT_WEIGHT 0x18
53#define ACTMON_DEV_AVG_COUNT 0x20
54#define ACTMON_DEV_INTR_STATUS 0x24
55
56#define ACTMON_INTR_STATUS_CLEAR 0xffffffff
57
58#define ACTMON_DEV_INTR_CONSECUTIVE_UPPER BIT(31)
59#define ACTMON_DEV_INTR_CONSECUTIVE_LOWER BIT(30)
60
61#define ACTMON_ABOVE_WMARK_WINDOW 1
62#define ACTMON_BELOW_WMARK_WINDOW 3
63#define ACTMON_BOOST_FREQ_STEP 16000
64
65/* activity counter is incremented every 256 memory transactions, and each
66 * transaction takes 4 EMC clocks for Tegra124; So the COUNT_WEIGHT is
67 * 4 * 256 = 1024.
68 */
69#define ACTMON_COUNT_WEIGHT 0x400
70
71/*
72 * ACTMON_AVERAGE_WINDOW_LOG2: default value for @DEV_CTRL_K_VAL, which
73 * translates to 2 ^ (K_VAL + 1). ex: 2 ^ (6 + 1) = 128
74 */
75#define ACTMON_AVERAGE_WINDOW_LOG2 6
76#define ACTMON_SAMPLING_PERIOD 12 /* ms */
77#define ACTMON_DEFAULT_AVG_BAND 6 /* 1/10 of % */
78
79#define KHZ 1000
80
81/* Assume that the bus is saturated if the utilization is 25% */
82#define BUS_SATURATION_RATIO 25
83
84/**
85 * struct tegra_devfreq_device_config - configuration specific to an ACTMON
86 * device
87 *
88 * Coefficients and thresholds are in %
89 */
90struct tegra_devfreq_device_config {
91 u32 offset;
92 u32 irq_mask;
93
94 unsigned int boost_up_coeff;
95 unsigned int boost_down_coeff;
96 unsigned int boost_up_threshold;
97 unsigned int boost_down_threshold;
98 u32 avg_dependency_threshold;
99};
100
101enum tegra_actmon_device {
102 MCALL = 0,
103 MCCPU,
104};
105
106static struct tegra_devfreq_device_config actmon_device_configs[] = {
107 {
108 /* MCALL */
109 .offset = 0x1c0,
110 .irq_mask = 1 << 26,
111 .boost_up_coeff = 200,
112 .boost_down_coeff = 50,
113 .boost_up_threshold = 60,
114 .boost_down_threshold = 40,
115 },
116 {
117 /* MCCPU */
118 .offset = 0x200,
119 .irq_mask = 1 << 25,
120 .boost_up_coeff = 800,
121 .boost_down_coeff = 90,
122 .boost_up_threshold = 27,
123 .boost_down_threshold = 10,
124 .avg_dependency_threshold = 50000,
125 },
126};
127
128/**
129 * struct tegra_devfreq_device - state specific to an ACTMON device
130 *
131 * Frequencies are in kHz.
132 */
133struct tegra_devfreq_device {
134 const struct tegra_devfreq_device_config *config;
135
136 void __iomem *regs;
137 u32 avg_band_freq;
138 u32 avg_count;
139
140 unsigned long target_freq;
141 unsigned long boost_freq;
142};
143
144struct tegra_devfreq {
145 struct devfreq *devfreq;
146
147 struct platform_device *pdev;
148 struct reset_control *reset;
149 struct clk *clock;
150 void __iomem *regs;
151
152 spinlock_t lock;
153
154 struct clk *emc_clock;
155 unsigned long max_freq;
156 unsigned long cur_freq;
157 struct notifier_block rate_change_nb;
158
159 struct tegra_devfreq_device devices[ARRAY_SIZE(actmon_device_configs)];
160};
161
162struct tegra_actmon_emc_ratio {
163 unsigned long cpu_freq;
164 unsigned long emc_freq;
165};
166
167static struct tegra_actmon_emc_ratio actmon_emc_ratios[] = {
168 { 1400000, ULONG_MAX },
169 { 1200000, 750000 },
170 { 1100000, 600000 },
171 { 1000000, 500000 },
172 { 800000, 375000 },
173 { 500000, 200000 },
174 { 250000, 100000 },
175};
176
177static unsigned long do_percent(unsigned long val, unsigned int pct)
178{
179 return val * pct / 100;
180}
181
182static void tegra_devfreq_update_avg_wmark(struct tegra_devfreq_device *dev)
183{
184 u32 avg = dev->avg_count;
185 u32 band = dev->avg_band_freq * ACTMON_SAMPLING_PERIOD;
186
187 writel(avg + band, dev->regs + ACTMON_DEV_AVG_UPPER_WMARK);
188 avg = max(avg, band);
189 writel(avg - band, dev->regs + ACTMON_DEV_AVG_LOWER_WMARK);
190}
191
192static void tegra_devfreq_update_wmark(struct tegra_devfreq *tegra,
193 struct tegra_devfreq_device *dev)
194{
195 u32 val = tegra->cur_freq * ACTMON_SAMPLING_PERIOD;
196
197 writel(do_percent(val, dev->config->boost_up_threshold),
198 dev->regs + ACTMON_DEV_UPPER_WMARK);
199
200 writel(do_percent(val, dev->config->boost_down_threshold),
201 dev->regs + ACTMON_DEV_LOWER_WMARK);
202}
203
204static void actmon_write_barrier(struct tegra_devfreq *tegra)
205{
206 /* ensure the update has reached the ACTMON */
207 wmb();
208 readl(tegra->regs + ACTMON_GLB_STATUS);
209}
210
211static irqreturn_t actmon_isr(int irq, void *data)
212{
213 struct tegra_devfreq *tegra = data;
214 struct tegra_devfreq_device *dev = NULL;
215 unsigned long flags;
216 u32 val;
217 unsigned int i;
218
219 val = readl(tegra->regs + ACTMON_GLB_STATUS);
220
221 for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
222 if (val & tegra->devices[i].config->irq_mask) {
223 dev = tegra->devices + i;
224 break;
225 }
226 }
227
228 if (!dev)
229 return IRQ_NONE;
230
231 spin_lock_irqsave(&tegra->lock, flags);
232
233 dev->avg_count = readl(dev->regs + ACTMON_DEV_AVG_COUNT);
234 tegra_devfreq_update_avg_wmark(dev);
235
236 val = readl(dev->regs + ACTMON_DEV_INTR_STATUS);
237 if (val & ACTMON_DEV_INTR_CONSECUTIVE_UPPER) {
238 val = readl(dev->regs + ACTMON_DEV_CTRL) |
239 ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN |
240 ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
241
242 /*
243 * new_boost = min(old_boost * up_coef + step, max_freq)
244 */
245 dev->boost_freq = do_percent(dev->boost_freq,
246 dev->config->boost_up_coeff);
247 dev->boost_freq += ACTMON_BOOST_FREQ_STEP;
248 if (dev->boost_freq >= tegra->max_freq) {
249 dev->boost_freq = tegra->max_freq;
250 val &= ~ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN;
251 }
252 writel(val, dev->regs + ACTMON_DEV_CTRL);
253 } else if (val & ACTMON_DEV_INTR_CONSECUTIVE_LOWER) {
254 val = readl(dev->regs + ACTMON_DEV_CTRL) |
255 ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN |
256 ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
257
258 /*
259 * new_boost = old_boost * down_coef
260 * or 0 if (old_boost * down_coef < step / 2)
261 */
262 dev->boost_freq = do_percent(dev->boost_freq,
263 dev->config->boost_down_coeff);
264 if (dev->boost_freq < (ACTMON_BOOST_FREQ_STEP >> 1)) {
265 dev->boost_freq = 0;
266 val &= ~ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
267 }
268 writel(val, dev->regs + ACTMON_DEV_CTRL);
269 }
270
271 if (dev->config->avg_dependency_threshold) {
272 val = readl(dev->regs + ACTMON_DEV_CTRL);
273 if (dev->avg_count >= dev->config->avg_dependency_threshold)
274 val |= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
275 else if (dev->boost_freq == 0)
276 val &= ~ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
277 writel(val, dev->regs + ACTMON_DEV_CTRL);
278 }
279
280 writel(ACTMON_INTR_STATUS_CLEAR, dev->regs + ACTMON_DEV_INTR_STATUS);
281
282 actmon_write_barrier(tegra);
283
284 spin_unlock_irqrestore(&tegra->lock, flags);
285
286 return IRQ_WAKE_THREAD;
287}
288
289static unsigned long actmon_cpu_to_emc_rate(struct tegra_devfreq *tegra,
290 unsigned long cpu_freq)
291{
292 unsigned int i;
293 struct tegra_actmon_emc_ratio *ratio = actmon_emc_ratios;
294
295 for (i = 0; i < ARRAY_SIZE(actmon_emc_ratios); i++, ratio++) {
296 if (cpu_freq >= ratio->cpu_freq) {
297 if (ratio->emc_freq >= tegra->max_freq)
298 return tegra->max_freq;
299 else
300 return ratio->emc_freq;
301 }
302 }
303
304 return 0;
305}
306
307static void actmon_update_target(struct tegra_devfreq *tegra,
308 struct tegra_devfreq_device *dev)
309{
310 unsigned long cpu_freq = 0;
311 unsigned long static_cpu_emc_freq = 0;
312 unsigned int avg_sustain_coef;
313 unsigned long flags;
314
315 if (dev->config->avg_dependency_threshold) {
316 cpu_freq = cpufreq_get(0);
317 static_cpu_emc_freq = actmon_cpu_to_emc_rate(tegra, cpu_freq);
318 }
319
320 spin_lock_irqsave(&tegra->lock, flags);
321
322 dev->target_freq = dev->avg_count / ACTMON_SAMPLING_PERIOD;
323 avg_sustain_coef = 100 * 100 / dev->config->boost_up_threshold;
324 dev->target_freq = do_percent(dev->target_freq, avg_sustain_coef);
325 dev->target_freq += dev->boost_freq;
326
327 if (dev->avg_count >= dev->config->avg_dependency_threshold)
328 dev->target_freq = max(dev->target_freq, static_cpu_emc_freq);
329
330 spin_unlock_irqrestore(&tegra->lock, flags);
331}
332
333static irqreturn_t actmon_thread_isr(int irq, void *data)
334{
335 struct tegra_devfreq *tegra = data;
336
337 mutex_lock(&tegra->devfreq->lock);
338 update_devfreq(tegra->devfreq);
339 mutex_unlock(&tegra->devfreq->lock);
340
341 return IRQ_HANDLED;
342}
343
344static int tegra_actmon_rate_notify_cb(struct notifier_block *nb,
345 unsigned long action, void *ptr)
346{
347 struct clk_notifier_data *data = ptr;
348 struct tegra_devfreq *tegra = container_of(nb, struct tegra_devfreq,
349 rate_change_nb);
350 unsigned int i;
351 unsigned long flags;
352
353 spin_lock_irqsave(&tegra->lock, flags);
354
355 switch (action) {
356 case POST_RATE_CHANGE:
357 tegra->cur_freq = data->new_rate / KHZ;
358
359 for (i = 0; i < ARRAY_SIZE(tegra->devices); i++)
360 tegra_devfreq_update_wmark(tegra, tegra->devices + i);
361
362 actmon_write_barrier(tegra);
363 break;
364 case PRE_RATE_CHANGE:
365 /* fall through */
366 case ABORT_RATE_CHANGE:
367 break;
368 };
369
370 spin_unlock_irqrestore(&tegra->lock, flags);
371
372 return NOTIFY_OK;
373}
374
375static void tegra_actmon_configure_device(struct tegra_devfreq *tegra,
376 struct tegra_devfreq_device *dev)
377{
378 u32 val;
379
380 dev->avg_band_freq = tegra->max_freq * ACTMON_DEFAULT_AVG_BAND / KHZ;
381 dev->target_freq = tegra->cur_freq;
382
383 dev->avg_count = tegra->cur_freq * ACTMON_SAMPLING_PERIOD;
384 writel(dev->avg_count, dev->regs + ACTMON_DEV_INIT_AVG);
385
386 tegra_devfreq_update_avg_wmark(dev);
387 tegra_devfreq_update_wmark(tegra, dev);
388
389 writel(ACTMON_COUNT_WEIGHT, dev->regs + ACTMON_DEV_COUNT_WEIGHT);
390 writel(ACTMON_INTR_STATUS_CLEAR, dev->regs + ACTMON_DEV_INTR_STATUS);
391
392 val = 0;
393 val |= ACTMON_DEV_CTRL_ENB_PERIODIC |
394 ACTMON_DEV_CTRL_AVG_ABOVE_WMARK_EN |
395 ACTMON_DEV_CTRL_AVG_BELOW_WMARK_EN;
396 val |= (ACTMON_AVERAGE_WINDOW_LOG2 - 1)
397 << ACTMON_DEV_CTRL_K_VAL_SHIFT;
398 val |= (ACTMON_BELOW_WMARK_WINDOW - 1)
399 << ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_NUM_SHIFT;
400 val |= (ACTMON_ABOVE_WMARK_WINDOW - 1)
401 << ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_NUM_SHIFT;
402 val |= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN |
403 ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN;
404
405 writel(val, dev->regs + ACTMON_DEV_CTRL);
406
407 actmon_write_barrier(tegra);
408
409 val = readl(dev->regs + ACTMON_DEV_CTRL);
410 val |= ACTMON_DEV_CTRL_ENB;
411 writel(val, dev->regs + ACTMON_DEV_CTRL);
412
413 actmon_write_barrier(tegra);
414}
415
416static int tegra_devfreq_suspend(struct device *dev)
417{
418 struct platform_device *pdev;
419 struct tegra_devfreq *tegra;
420 struct tegra_devfreq_device *actmon_dev;
421 unsigned int i;
422 u32 val;
423
424 pdev = container_of(dev, struct platform_device, dev);
425 tegra = platform_get_drvdata(pdev);
426
427 for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
428 actmon_dev = &tegra->devices[i];
429
430 val = readl(actmon_dev->regs + ACTMON_DEV_CTRL);
431 val &= ~ACTMON_DEV_CTRL_ENB;
432 writel(val, actmon_dev->regs + ACTMON_DEV_CTRL);
433
434 writel(ACTMON_INTR_STATUS_CLEAR,
435 actmon_dev->regs + ACTMON_DEV_INTR_STATUS);
436
437 actmon_write_barrier(tegra);
438 }
439
440 return 0;
441}
442
443static int tegra_devfreq_resume(struct device *dev)
444{
445 struct platform_device *pdev;
446 struct tegra_devfreq *tegra;
447 struct tegra_devfreq_device *actmon_dev;
448 unsigned int i;
449
450 pdev = container_of(dev, struct platform_device, dev);
451 tegra = platform_get_drvdata(pdev);
452
453 for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
454 actmon_dev = &tegra->devices[i];
455
456 tegra_actmon_configure_device(tegra, actmon_dev);
457 }
458
459 return 0;
460}
461
462static int tegra_devfreq_target(struct device *dev, unsigned long *freq,
463 u32 flags)
464{
465 struct platform_device *pdev;
466 struct tegra_devfreq *tegra;
467 struct dev_pm_opp *opp;
468 unsigned long rate = *freq * KHZ;
469
470 pdev = container_of(dev, struct platform_device, dev);
471 tegra = platform_get_drvdata(pdev);
472
473 rcu_read_lock();
474 opp = devfreq_recommended_opp(dev, &rate, flags);
475 if (IS_ERR(opp)) {
476 rcu_read_unlock();
477 dev_err(dev, "Failed to find opp for %lu KHz\n", *freq);
478 return PTR_ERR(opp);
479 }
480 rate = dev_pm_opp_get_freq(opp);
481 rcu_read_unlock();
482
483 /* TODO: Once we have per-user clk constraints, set a floor */
484 clk_set_rate(tegra->emc_clock, rate);
485
486 /* TODO: Set voltage as well */
487
488 return 0;
489}
490
491static int tegra_devfreq_get_dev_status(struct device *dev,
492 struct devfreq_dev_status *stat)
493{
494 struct platform_device *pdev;
495 struct tegra_devfreq *tegra;
496 struct tegra_devfreq_device *actmon_dev;
497
498 pdev = container_of(dev, struct platform_device, dev);
499 tegra = platform_get_drvdata(pdev);
500
501 stat->current_frequency = tegra->cur_freq;
502
503 /* To be used by the tegra governor */
504 stat->private_data = tegra;
505
506 /* The below are to be used by the other governors */
507
508 actmon_dev = &tegra->devices[MCALL];
509
510 /* Number of cycles spent on memory access */
511 stat->busy_time = actmon_dev->avg_count;
512
513 /* The bus can be considered to be saturated way before 100% */
514 stat->busy_time *= 100 / BUS_SATURATION_RATIO;
515
516 /* Number of cycles in a sampling period */
517 stat->total_time = ACTMON_SAMPLING_PERIOD * tegra->cur_freq;
518
519 return 0;
520}
521
522static int tegra_devfreq_get_target(struct devfreq *devfreq,
523 unsigned long *freq)
524{
525 struct devfreq_dev_status stat;
526 struct tegra_devfreq *tegra;
527 struct tegra_devfreq_device *dev;
528 unsigned long target_freq = 0;
529 unsigned int i;
530 int err;
531
532 err = devfreq->profile->get_dev_status(devfreq->dev.parent, &stat);
533 if (err)
534 return err;
535
536 tegra = stat.private_data;
537
538 for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
539 dev = &tegra->devices[i];
540
541 actmon_update_target(tegra, dev);
542
543 target_freq = max(target_freq, dev->target_freq);
544 }
545
546 *freq = target_freq;
547
548 return 0;
549}
550
551static int tegra_devfreq_event_handler(struct devfreq *devfreq,
552 unsigned int event, void *data)
553{
554 return 0;
555}
556
557static struct devfreq_governor tegra_devfreq_governor = {
558 .name = "tegra",
559 .get_target_freq = tegra_devfreq_get_target,
560 .event_handler = tegra_devfreq_event_handler,
561};
562
563static struct devfreq_dev_profile tegra_devfreq_profile = {
564 .polling_ms = 0,
565 .target = tegra_devfreq_target,
566 .get_dev_status = tegra_devfreq_get_dev_status,
567};
568
569static int tegra_devfreq_probe(struct platform_device *pdev)
570{
571 struct tegra_devfreq *tegra;
572 struct tegra_devfreq_device *dev;
573 struct resource *res;
574 unsigned long max_freq;
575 unsigned int i;
576 int irq;
577 int err;
578
579 tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL);
580 if (!tegra)
581 return -ENOMEM;
582
583 spin_lock_init(&tegra->lock);
584
585 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
586 if (!res) {
587 dev_err(&pdev->dev, "Failed to get regs resource\n");
588 return -ENODEV;
589 }
590
591 tegra->regs = devm_ioremap_resource(&pdev->dev, res);
592 if (IS_ERR(tegra->regs)) {
593 dev_err(&pdev->dev, "Failed to get IO memory\n");
594 return PTR_ERR(tegra->regs);
595 }
596
597 tegra->reset = devm_reset_control_get(&pdev->dev, "actmon");
598 if (IS_ERR(tegra->reset)) {
599 dev_err(&pdev->dev, "Failed to get reset\n");
600 return PTR_ERR(tegra->reset);
601 }
602
603 tegra->clock = devm_clk_get(&pdev->dev, "actmon");
604 if (IS_ERR(tegra->clock)) {
605 dev_err(&pdev->dev, "Failed to get actmon clock\n");
606 return PTR_ERR(tegra->clock);
607 }
608
609 tegra->emc_clock = devm_clk_get(&pdev->dev, "emc");
610 if (IS_ERR(tegra->emc_clock)) {
611 dev_err(&pdev->dev, "Failed to get emc clock\n");
612 return PTR_ERR(tegra->emc_clock);
613 }
614
615 err = of_init_opp_table(&pdev->dev);
616 if (err) {
617 dev_err(&pdev->dev, "Failed to init operating point table\n");
618 return err;
619 }
620
621 tegra->rate_change_nb.notifier_call = tegra_actmon_rate_notify_cb;
622 err = clk_notifier_register(tegra->emc_clock, &tegra->rate_change_nb);
623 if (err) {
624 dev_err(&pdev->dev,
625 "Failed to register rate change notifier\n");
626 return err;
627 }
628
629 reset_control_assert(tegra->reset);
630
631 err = clk_prepare_enable(tegra->clock);
632 if (err) {
633 reset_control_deassert(tegra->reset);
634 return err;
635 }
636
637 reset_control_deassert(tegra->reset);
638
639 max_freq = clk_round_rate(tegra->emc_clock, ULONG_MAX);
640 tegra->max_freq = max_freq / KHZ;
641
642 clk_set_rate(tegra->emc_clock, max_freq);
643
644 tegra->cur_freq = clk_get_rate(tegra->emc_clock) / KHZ;
645
646 writel(ACTMON_SAMPLING_PERIOD - 1,
647 tegra->regs + ACTMON_GLB_PERIOD_CTRL);
648
649 for (i = 0; i < ARRAY_SIZE(actmon_device_configs); i++) {
650 dev = tegra->devices + i;
651 dev->config = actmon_device_configs + i;
652 dev->regs = tegra->regs + dev->config->offset;
653
654 tegra_actmon_configure_device(tegra, tegra->devices + i);
655 }
656
657 err = devfreq_add_governor(&tegra_devfreq_governor);
658 if (err) {
659 dev_err(&pdev->dev, "Failed to add governor\n");
660 return err;
661 }
662
663 tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock);
664 tegra->devfreq = devm_devfreq_add_device(&pdev->dev,
665 &tegra_devfreq_profile,
666 "tegra",
667 NULL);
668
669 irq = platform_get_irq(pdev, 0);
670 err = devm_request_threaded_irq(&pdev->dev, irq, actmon_isr,
671 actmon_thread_isr, IRQF_SHARED,
672 "tegra-devfreq", tegra);
673 if (err) {
674 dev_err(&pdev->dev, "Interrupt request failed\n");
675 return err;
676 }
677
678 platform_set_drvdata(pdev, tegra);
679
680 return 0;
681}
682
683static int tegra_devfreq_remove(struct platform_device *pdev)
684{
685 struct tegra_devfreq *tegra = platform_get_drvdata(pdev);
686
687 clk_notifier_unregister(tegra->emc_clock, &tegra->rate_change_nb);
688
689 clk_disable_unprepare(tegra->clock);
690
691 return 0;
692}
693
694static SIMPLE_DEV_PM_OPS(tegra_devfreq_pm_ops,
695 tegra_devfreq_suspend,
696 tegra_devfreq_resume);
697
698static struct of_device_id tegra_devfreq_of_match[] = {
699 { .compatible = "nvidia,tegra124-actmon" },
700 { },
701};
702
703static struct platform_driver tegra_devfreq_driver = {
704 .probe = tegra_devfreq_probe,
705 .remove = tegra_devfreq_remove,
706 .driver = {
707 .name = "tegra-devfreq",
708 .owner = THIS_MODULE,
709 .of_match_table = tegra_devfreq_of_match,
710 .pm = &tegra_devfreq_pm_ops,
711 },
712};
713module_platform_driver(tegra_devfreq_driver);
714
715MODULE_LICENSE("GPL");
716MODULE_DESCRIPTION("Tegra devfreq driver");
717MODULE_AUTHOR("Tomeu Vizoso <tomeu.vizoso@collabora.com>");
718MODULE_DEVICE_TABLE(of, tegra_devfreq_of_match);
generated by cgit v1.2.2 (git 2.25.0) at 2025-09-02 02:53:44 -0400