2 * A devfreq driver for NVIDIA Tegra SoCs
4 * Copyright (c) 2014 NVIDIA CORPORATION. All rights reserved.
5 * Copyright (C) 2014 Google, Inc
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.
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
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/>.
21 #include <linux/clk.h>
22 #include <linux/cpufreq.h>
23 #include <linux/devfreq.h>
24 #include <linux/interrupt.h>
26 #include <linux/module.h>
27 #include <linux/platform_device.h>
28 #include <linux/pm_opp.h>
29 #include <linux/reset.h>
33 #define ACTMON_GLB_STATUS 0x0
34 #define ACTMON_GLB_PERIOD_CTRL 0x4
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)
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
56 #define ACTMON_INTR_STATUS_CLEAR 0xffffffff
58 #define ACTMON_DEV_INTR_CONSECUTIVE_UPPER BIT(31)
59 #define ACTMON_DEV_INTR_CONSECUTIVE_LOWER BIT(30)
61 #define ACTMON_ABOVE_WMARK_WINDOW 1
62 #define ACTMON_BELOW_WMARK_WINDOW 3
63 #define ACTMON_BOOST_FREQ_STEP 16000
66 * Activity counter is incremented every 256 memory transactions, and each
67 * transaction takes 4 EMC clocks for Tegra124; So the COUNT_WEIGHT is
70 #define ACTMON_COUNT_WEIGHT 0x400
73 * ACTMON_AVERAGE_WINDOW_LOG2: default value for @DEV_CTRL_K_VAL, which
74 * translates to 2 ^ (K_VAL + 1). ex: 2 ^ (6 + 1) = 128
76 #define ACTMON_AVERAGE_WINDOW_LOG2 6
77 #define ACTMON_SAMPLING_PERIOD 12 /* ms */
78 #define ACTMON_DEFAULT_AVG_BAND 6 /* 1/10 of % */
82 /* Assume that the bus is saturated if the utilization is 25% */
83 #define BUS_SATURATION_RATIO 25
86 * struct tegra_devfreq_device_config - configuration specific to an ACTMON
89 * Coefficients and thresholds are percentages unless otherwise noted
91 struct tegra_devfreq_device_config
{
95 /* Factors applied to boost_freq every consecutive watermark breach */
96 unsigned int boost_up_coeff
;
97 unsigned int boost_down_coeff
;
99 /* Define the watermark bounds when applied to the current avg */
100 unsigned int boost_up_threshold
;
101 unsigned int boost_down_threshold
;
104 * Threshold of activity (cycles) below which the CPU frequency isn't
105 * to be taken into account. This is to avoid increasing the EMC
106 * frequency when the CPU is very busy but not accessing the bus often.
108 u32 avg_dependency_threshold
;
111 enum tegra_actmon_device
{
116 static struct tegra_devfreq_device_config actmon_device_configs
[] = {
118 /* MCALL: All memory accesses (including from the CPUs) */
121 .boost_up_coeff
= 200,
122 .boost_down_coeff
= 50,
123 .boost_up_threshold
= 60,
124 .boost_down_threshold
= 40,
127 /* MCCPU: memory accesses from the CPUs */
130 .boost_up_coeff
= 800,
131 .boost_down_coeff
= 90,
132 .boost_up_threshold
= 27,
133 .boost_down_threshold
= 10,
134 .avg_dependency_threshold
= 50000,
139 * struct tegra_devfreq_device - state specific to an ACTMON device
141 * Frequencies are in kHz.
143 struct tegra_devfreq_device
{
144 const struct tegra_devfreq_device_config
*config
;
148 /* Average event count sampled in the last interrupt */
152 * Extra frequency to increase the target by due to consecutive
153 * watermark breaches.
155 unsigned long boost_freq
;
157 /* Optimal frequency calculated from the stats for this device */
158 unsigned long target_freq
;
161 struct tegra_devfreq
{
162 struct devfreq
*devfreq
;
164 struct reset_control
*reset
;
168 struct clk
*emc_clock
;
169 unsigned long max_freq
;
170 unsigned long cur_freq
;
171 struct notifier_block rate_change_nb
;
173 struct tegra_devfreq_device devices
[ARRAY_SIZE(actmon_device_configs
)];
176 struct tegra_actmon_emc_ratio
{
177 unsigned long cpu_freq
;
178 unsigned long emc_freq
;
181 static struct tegra_actmon_emc_ratio actmon_emc_ratios
[] = {
182 { 1400000, ULONG_MAX
},
191 static u32
actmon_readl(struct tegra_devfreq
*tegra
, u32 offset
)
193 return readl(tegra
->regs
+ offset
);
196 static void actmon_writel(struct tegra_devfreq
*tegra
, u32 val
, u32 offset
)
198 writel(val
, tegra
->regs
+ offset
);
201 static u32
device_readl(struct tegra_devfreq_device
*dev
, u32 offset
)
203 return readl(dev
->regs
+ offset
);
206 static void device_writel(struct tegra_devfreq_device
*dev
, u32 val
,
209 writel(val
, dev
->regs
+ offset
);
212 static unsigned long do_percent(unsigned long val
, unsigned int pct
)
214 return val
* pct
/ 100;
217 static void tegra_devfreq_update_avg_wmark(struct tegra_devfreq
*tegra
,
218 struct tegra_devfreq_device
*dev
)
220 u32 avg
= dev
->avg_count
;
221 u32 avg_band_freq
= tegra
->max_freq
* ACTMON_DEFAULT_AVG_BAND
/ KHZ
;
222 u32 band
= avg_band_freq
* ACTMON_SAMPLING_PERIOD
;
224 device_writel(dev
, avg
+ band
, ACTMON_DEV_AVG_UPPER_WMARK
);
226 avg
= max(dev
->avg_count
, band
);
227 device_writel(dev
, avg
- band
, ACTMON_DEV_AVG_LOWER_WMARK
);
230 static void tegra_devfreq_update_wmark(struct tegra_devfreq
*tegra
,
231 struct tegra_devfreq_device
*dev
)
233 u32 val
= tegra
->cur_freq
* ACTMON_SAMPLING_PERIOD
;
235 device_writel(dev
, do_percent(val
, dev
->config
->boost_up_threshold
),
236 ACTMON_DEV_UPPER_WMARK
);
238 device_writel(dev
, do_percent(val
, dev
->config
->boost_down_threshold
),
239 ACTMON_DEV_LOWER_WMARK
);
242 static void actmon_write_barrier(struct tegra_devfreq
*tegra
)
244 /* ensure the update has reached the ACTMON */
246 actmon_readl(tegra
, ACTMON_GLB_STATUS
);
249 static void actmon_isr_device(struct tegra_devfreq
*tegra
,
250 struct tegra_devfreq_device
*dev
)
253 u32 intr_status
, dev_ctrl
;
255 spin_lock_irqsave(&dev
->lock
, flags
);
257 dev
->avg_count
= device_readl(dev
, ACTMON_DEV_AVG_COUNT
);
258 tegra_devfreq_update_avg_wmark(tegra
, dev
);
260 intr_status
= device_readl(dev
, ACTMON_DEV_INTR_STATUS
);
261 dev_ctrl
= device_readl(dev
, ACTMON_DEV_CTRL
);
263 if (intr_status
& ACTMON_DEV_INTR_CONSECUTIVE_UPPER
) {
265 * new_boost = min(old_boost * up_coef + step, max_freq)
267 dev
->boost_freq
= do_percent(dev
->boost_freq
,
268 dev
->config
->boost_up_coeff
);
269 dev
->boost_freq
+= ACTMON_BOOST_FREQ_STEP
;
271 dev_ctrl
|= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN
;
273 if (dev
->boost_freq
>= tegra
->max_freq
)
274 dev
->boost_freq
= tegra
->max_freq
;
276 dev_ctrl
|= ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN
;
277 } else if (intr_status
& ACTMON_DEV_INTR_CONSECUTIVE_LOWER
) {
279 * new_boost = old_boost * down_coef
280 * or 0 if (old_boost * down_coef < step / 2)
282 dev
->boost_freq
= do_percent(dev
->boost_freq
,
283 dev
->config
->boost_down_coeff
);
285 dev_ctrl
|= ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN
;
287 if (dev
->boost_freq
< (ACTMON_BOOST_FREQ_STEP
>> 1))
290 dev_ctrl
|= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN
;
293 if (dev
->config
->avg_dependency_threshold
) {
294 if (dev
->avg_count
>= dev
->config
->avg_dependency_threshold
)
295 dev_ctrl
|= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN
;
296 else if (dev
->boost_freq
== 0)
297 dev_ctrl
&= ~ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN
;
300 device_writel(dev
, dev_ctrl
, ACTMON_DEV_CTRL
);
302 device_writel(dev
, ACTMON_INTR_STATUS_CLEAR
, ACTMON_DEV_INTR_STATUS
);
304 actmon_write_barrier(tegra
);
306 spin_unlock_irqrestore(&dev
->lock
, flags
);
309 static irqreturn_t
actmon_isr(int irq
, void *data
)
311 struct tegra_devfreq
*tegra
= data
;
312 bool handled
= false;
316 val
= actmon_readl(tegra
, ACTMON_GLB_STATUS
);
317 for (i
= 0; i
< ARRAY_SIZE(tegra
->devices
); i
++) {
318 if (val
& tegra
->devices
[i
].config
->irq_mask
) {
319 actmon_isr_device(tegra
, tegra
->devices
+ i
);
324 return handled
? IRQ_WAKE_THREAD
: IRQ_NONE
;
327 static unsigned long actmon_cpu_to_emc_rate(struct tegra_devfreq
*tegra
,
328 unsigned long cpu_freq
)
331 struct tegra_actmon_emc_ratio
*ratio
= actmon_emc_ratios
;
333 for (i
= 0; i
< ARRAY_SIZE(actmon_emc_ratios
); i
++, ratio
++) {
334 if (cpu_freq
>= ratio
->cpu_freq
) {
335 if (ratio
->emc_freq
>= tegra
->max_freq
)
336 return tegra
->max_freq
;
338 return ratio
->emc_freq
;
345 static void actmon_update_target(struct tegra_devfreq
*tegra
,
346 struct tegra_devfreq_device
*dev
)
348 unsigned long cpu_freq
= 0;
349 unsigned long static_cpu_emc_freq
= 0;
350 unsigned int avg_sustain_coef
;
353 if (dev
->config
->avg_dependency_threshold
) {
354 cpu_freq
= cpufreq_get(0);
355 static_cpu_emc_freq
= actmon_cpu_to_emc_rate(tegra
, cpu_freq
);
358 spin_lock_irqsave(&dev
->lock
, flags
);
360 dev
->target_freq
= dev
->avg_count
/ ACTMON_SAMPLING_PERIOD
;
361 avg_sustain_coef
= 100 * 100 / dev
->config
->boost_up_threshold
;
362 dev
->target_freq
= do_percent(dev
->target_freq
, avg_sustain_coef
);
363 dev
->target_freq
+= dev
->boost_freq
;
365 if (dev
->avg_count
>= dev
->config
->avg_dependency_threshold
)
366 dev
->target_freq
= max(dev
->target_freq
, static_cpu_emc_freq
);
368 spin_unlock_irqrestore(&dev
->lock
, flags
);
371 static irqreturn_t
actmon_thread_isr(int irq
, void *data
)
373 struct tegra_devfreq
*tegra
= data
;
375 mutex_lock(&tegra
->devfreq
->lock
);
376 update_devfreq(tegra
->devfreq
);
377 mutex_unlock(&tegra
->devfreq
->lock
);
382 static int tegra_actmon_rate_notify_cb(struct notifier_block
*nb
,
383 unsigned long action
, void *ptr
)
385 struct clk_notifier_data
*data
= ptr
;
386 struct tegra_devfreq
*tegra
;
387 struct tegra_devfreq_device
*dev
;
391 if (action
!= POST_RATE_CHANGE
)
394 tegra
= container_of(nb
, struct tegra_devfreq
, rate_change_nb
);
396 tegra
->cur_freq
= data
->new_rate
/ KHZ
;
398 for (i
= 0; i
< ARRAY_SIZE(tegra
->devices
); i
++) {
399 dev
= &tegra
->devices
[i
];
401 spin_lock_irqsave(&dev
->lock
, flags
);
402 tegra_devfreq_update_wmark(tegra
, dev
);
403 spin_unlock_irqrestore(&dev
->lock
, flags
);
406 actmon_write_barrier(tegra
);
411 static void tegra_actmon_enable_interrupts(struct tegra_devfreq
*tegra
)
413 struct tegra_devfreq_device
*dev
;
417 for (i
= 0; i
< ARRAY_SIZE(tegra
->devices
); i
++) {
418 dev
= &tegra
->devices
[i
];
420 val
= device_readl(dev
, ACTMON_DEV_CTRL
);
421 val
|= ACTMON_DEV_CTRL_AVG_ABOVE_WMARK_EN
;
422 val
|= ACTMON_DEV_CTRL_AVG_BELOW_WMARK_EN
;
423 val
|= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN
;
424 val
|= ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN
;
426 device_writel(dev
, val
, ACTMON_DEV_CTRL
);
429 actmon_write_barrier(tegra
);
432 static void tegra_actmon_disable_interrupts(struct tegra_devfreq
*tegra
)
434 struct tegra_devfreq_device
*dev
;
438 for (i
= 0; i
< ARRAY_SIZE(tegra
->devices
); i
++) {
439 dev
= &tegra
->devices
[i
];
441 val
= device_readl(dev
, ACTMON_DEV_CTRL
);
442 val
&= ~ACTMON_DEV_CTRL_AVG_ABOVE_WMARK_EN
;
443 val
&= ~ACTMON_DEV_CTRL_AVG_BELOW_WMARK_EN
;
444 val
&= ~ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN
;
445 val
&= ~ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN
;
447 device_writel(dev
, val
, ACTMON_DEV_CTRL
);
450 actmon_write_barrier(tegra
);
453 static void tegra_actmon_configure_device(struct tegra_devfreq
*tegra
,
454 struct tegra_devfreq_device
*dev
)
458 dev
->target_freq
= tegra
->cur_freq
;
460 dev
->avg_count
= tegra
->cur_freq
* ACTMON_SAMPLING_PERIOD
;
461 device_writel(dev
, dev
->avg_count
, ACTMON_DEV_INIT_AVG
);
463 tegra_devfreq_update_avg_wmark(tegra
, dev
);
464 tegra_devfreq_update_wmark(tegra
, dev
);
466 device_writel(dev
, ACTMON_COUNT_WEIGHT
, ACTMON_DEV_COUNT_WEIGHT
);
467 device_writel(dev
, ACTMON_INTR_STATUS_CLEAR
, ACTMON_DEV_INTR_STATUS
);
469 val
|= ACTMON_DEV_CTRL_ENB_PERIODIC
;
470 val
|= (ACTMON_AVERAGE_WINDOW_LOG2
- 1)
471 << ACTMON_DEV_CTRL_K_VAL_SHIFT
;
472 val
|= (ACTMON_BELOW_WMARK_WINDOW
- 1)
473 << ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_NUM_SHIFT
;
474 val
|= (ACTMON_ABOVE_WMARK_WINDOW
- 1)
475 << ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_NUM_SHIFT
;
476 val
|= ACTMON_DEV_CTRL_ENB
;
478 device_writel(dev
, val
, ACTMON_DEV_CTRL
);
480 actmon_write_barrier(tegra
);
483 static int tegra_devfreq_target(struct device
*dev
, unsigned long *freq
,
486 struct tegra_devfreq
*tegra
= dev_get_drvdata(dev
);
487 struct dev_pm_opp
*opp
;
488 unsigned long rate
= *freq
* KHZ
;
491 opp
= devfreq_recommended_opp(dev
, &rate
, flags
);
494 dev_err(dev
, "Failed to find opp for %lu KHz\n", *freq
);
497 rate
= dev_pm_opp_get_freq(opp
);
500 clk_set_min_rate(tegra
->emc_clock
, rate
);
501 clk_set_rate(tegra
->emc_clock
, 0);
508 static int tegra_devfreq_get_dev_status(struct device
*dev
,
509 struct devfreq_dev_status
*stat
)
511 struct tegra_devfreq
*tegra
= dev_get_drvdata(dev
);
512 struct tegra_devfreq_device
*actmon_dev
;
514 stat
->current_frequency
= tegra
->cur_freq
;
516 /* To be used by the tegra governor */
517 stat
->private_data
= tegra
;
519 /* The below are to be used by the other governors */
521 actmon_dev
= &tegra
->devices
[MCALL
];
523 /* Number of cycles spent on memory access */
524 stat
->busy_time
= device_readl(actmon_dev
, ACTMON_DEV_AVG_COUNT
);
526 /* The bus can be considered to be saturated way before 100% */
527 stat
->busy_time
*= 100 / BUS_SATURATION_RATIO
;
529 /* Number of cycles in a sampling period */
530 stat
->total_time
= ACTMON_SAMPLING_PERIOD
* tegra
->cur_freq
;
532 stat
->busy_time
= min(stat
->busy_time
, stat
->total_time
);
537 static struct devfreq_dev_profile tegra_devfreq_profile
= {
539 .target
= tegra_devfreq_target
,
540 .get_dev_status
= tegra_devfreq_get_dev_status
,
543 static int tegra_governor_get_target(struct devfreq
*devfreq
,
546 struct devfreq_dev_status
*stat
;
547 struct tegra_devfreq
*tegra
;
548 struct tegra_devfreq_device
*dev
;
549 unsigned long target_freq
= 0;
553 err
= devfreq_update_stats(devfreq
);
557 stat
= &devfreq
->last_status
;
559 tegra
= stat
->private_data
;
561 for (i
= 0; i
< ARRAY_SIZE(tegra
->devices
); i
++) {
562 dev
= &tegra
->devices
[i
];
564 actmon_update_target(tegra
, dev
);
566 target_freq
= max(target_freq
, dev
->target_freq
);
574 static int tegra_governor_event_handler(struct devfreq
*devfreq
,
575 unsigned int event
, void *data
)
577 struct tegra_devfreq
*tegra
;
580 tegra
= dev_get_drvdata(devfreq
->dev
.parent
);
583 case DEVFREQ_GOV_START
:
584 devfreq_monitor_start(devfreq
);
585 tegra_actmon_enable_interrupts(tegra
);
588 case DEVFREQ_GOV_STOP
:
589 tegra_actmon_disable_interrupts(tegra
);
590 devfreq_monitor_stop(devfreq
);
593 case DEVFREQ_GOV_SUSPEND
:
594 tegra_actmon_disable_interrupts(tegra
);
595 devfreq_monitor_suspend(devfreq
);
598 case DEVFREQ_GOV_RESUME
:
599 devfreq_monitor_resume(devfreq
);
600 tegra_actmon_enable_interrupts(tegra
);
607 static struct devfreq_governor tegra_devfreq_governor
= {
608 .name
= "tegra_actmon",
609 .get_target_freq
= tegra_governor_get_target
,
610 .event_handler
= tegra_governor_event_handler
,
613 static int tegra_devfreq_probe(struct platform_device
*pdev
)
615 struct tegra_devfreq
*tegra
;
616 struct tegra_devfreq_device
*dev
;
617 struct resource
*res
;
623 tegra
= devm_kzalloc(&pdev
->dev
, sizeof(*tegra
), GFP_KERNEL
);
627 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
629 tegra
->regs
= devm_ioremap_resource(&pdev
->dev
, res
);
630 if (IS_ERR(tegra
->regs
))
631 return PTR_ERR(tegra
->regs
);
633 tegra
->reset
= devm_reset_control_get(&pdev
->dev
, "actmon");
634 if (IS_ERR(tegra
->reset
)) {
635 dev_err(&pdev
->dev
, "Failed to get reset\n");
636 return PTR_ERR(tegra
->reset
);
639 tegra
->clock
= devm_clk_get(&pdev
->dev
, "actmon");
640 if (IS_ERR(tegra
->clock
)) {
641 dev_err(&pdev
->dev
, "Failed to get actmon clock\n");
642 return PTR_ERR(tegra
->clock
);
645 tegra
->emc_clock
= devm_clk_get(&pdev
->dev
, "emc");
646 if (IS_ERR(tegra
->emc_clock
)) {
647 dev_err(&pdev
->dev
, "Failed to get emc clock\n");
648 return PTR_ERR(tegra
->emc_clock
);
651 clk_set_rate(tegra
->emc_clock
, ULONG_MAX
);
653 tegra
->rate_change_nb
.notifier_call
= tegra_actmon_rate_notify_cb
;
654 err
= clk_notifier_register(tegra
->emc_clock
, &tegra
->rate_change_nb
);
657 "Failed to register rate change notifier\n");
661 reset_control_assert(tegra
->reset
);
663 err
= clk_prepare_enable(tegra
->clock
);
666 "Failed to prepare and enable ACTMON clock\n");
670 reset_control_deassert(tegra
->reset
);
672 tegra
->max_freq
= clk_round_rate(tegra
->emc_clock
, ULONG_MAX
) / KHZ
;
673 tegra
->cur_freq
= clk_get_rate(tegra
->emc_clock
) / KHZ
;
675 actmon_writel(tegra
, ACTMON_SAMPLING_PERIOD
- 1,
676 ACTMON_GLB_PERIOD_CTRL
);
678 for (i
= 0; i
< ARRAY_SIZE(actmon_device_configs
); i
++) {
679 dev
= tegra
->devices
+ i
;
680 dev
->config
= actmon_device_configs
+ i
;
681 dev
->regs
= tegra
->regs
+ dev
->config
->offset
;
682 spin_lock_init(&dev
->lock
);
684 tegra_actmon_configure_device(tegra
, dev
);
687 for (rate
= 0; rate
<= tegra
->max_freq
* KHZ
; rate
++) {
688 rate
= clk_round_rate(tegra
->emc_clock
, rate
);
689 dev_pm_opp_add(&pdev
->dev
, rate
, 0);
692 irq
= platform_get_irq(pdev
, 0);
694 dev_err(&pdev
->dev
, "Failed to get IRQ\n");
698 platform_set_drvdata(pdev
, tegra
);
700 err
= devm_request_threaded_irq(&pdev
->dev
, irq
, actmon_isr
,
701 actmon_thread_isr
, IRQF_SHARED
,
702 "tegra-devfreq", tegra
);
704 dev_err(&pdev
->dev
, "Interrupt request failed\n");
708 tegra_devfreq_profile
.initial_freq
= clk_get_rate(tegra
->emc_clock
);
709 tegra
->devfreq
= devm_devfreq_add_device(&pdev
->dev
,
710 &tegra_devfreq_profile
,
717 static int tegra_devfreq_remove(struct platform_device
*pdev
)
719 struct tegra_devfreq
*tegra
= platform_get_drvdata(pdev
);
720 int irq
= platform_get_irq(pdev
, 0);
724 for (i
= 0; i
< ARRAY_SIZE(actmon_device_configs
); i
++) {
725 val
= device_readl(&tegra
->devices
[i
], ACTMON_DEV_CTRL
);
726 val
&= ~ACTMON_DEV_CTRL_ENB
;
727 device_writel(&tegra
->devices
[i
], val
, ACTMON_DEV_CTRL
);
730 actmon_write_barrier(tegra
);
732 devm_free_irq(&pdev
->dev
, irq
, tegra
);
734 clk_notifier_unregister(tegra
->emc_clock
, &tegra
->rate_change_nb
);
736 clk_disable_unprepare(tegra
->clock
);
741 static const struct of_device_id tegra_devfreq_of_match
[] = {
742 { .compatible
= "nvidia,tegra124-actmon" },
746 MODULE_DEVICE_TABLE(of
, tegra_devfreq_of_match
);
748 static struct platform_driver tegra_devfreq_driver
= {
749 .probe
= tegra_devfreq_probe
,
750 .remove
= tegra_devfreq_remove
,
752 .name
= "tegra-devfreq",
753 .of_match_table
= tegra_devfreq_of_match
,
757 static int __init
tegra_devfreq_init(void)
761 ret
= devfreq_add_governor(&tegra_devfreq_governor
);
763 pr_err("%s: failed to add governor: %d\n", __func__
, ret
);
767 ret
= platform_driver_register(&tegra_devfreq_driver
);
769 devfreq_remove_governor(&tegra_devfreq_governor
);
773 module_init(tegra_devfreq_init
)
775 static void __exit
tegra_devfreq_exit(void)
779 platform_driver_unregister(&tegra_devfreq_driver
);
781 ret
= devfreq_remove_governor(&tegra_devfreq_governor
);
783 pr_err("%s: failed to remove governor: %d\n", __func__
, ret
);
785 module_exit(tegra_devfreq_exit
)
787 MODULE_LICENSE("GPL v2");
788 MODULE_DESCRIPTION("Tegra devfreq driver");
789 MODULE_AUTHOR("Tomeu Vizoso <tomeu.vizoso@collabora.com>");