1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Marvell EBU Armada SoCs thermal sensor driver
4 *
5 * Copyright (C) 2013 Marvell
6 */
7#include <linux/device.h>
8#include <linux/err.h>
9#include <linux/io.h>
10#include <linux/kernel.h>
11#include <linux/of.h>
12#include <linux/module.h>
13#include <linux/delay.h>
14#include <linux/platform_device.h>
15#include <linux/of_device.h>
16#include <linux/thermal.h>
17#include <linux/iopoll.h>
18#include <linux/mfd/syscon.h>
19#include <linux/regmap.h>
20#include <linux/interrupt.h>
21
22#include "thermal_core.h"
23
24/* Thermal Manager Control and Status Register */
25#define PMU_TDC0_SW_RST_MASK		(0x1 << 1)
26#define PMU_TM_DISABLE_OFFS		0
27#define PMU_TM_DISABLE_MASK		(0x1 << PMU_TM_DISABLE_OFFS)
28#define PMU_TDC0_REF_CAL_CNT_OFFS	11
29#define PMU_TDC0_REF_CAL_CNT_MASK	(0x1ff << PMU_TDC0_REF_CAL_CNT_OFFS)
30#define PMU_TDC0_OTF_CAL_MASK		(0x1 << 30)
31#define PMU_TDC0_START_CAL_MASK		(0x1 << 25)
32
33#define A375_UNIT_CONTROL_SHIFT		27
34#define A375_UNIT_CONTROL_MASK		0x7
35#define A375_READOUT_INVERT		BIT(15)
36#define A375_HW_RESETn			BIT(8)
37
38/* Errata fields */
39#define CONTROL0_TSEN_TC_TRIM_MASK	0x7
40#define CONTROL0_TSEN_TC_TRIM_VAL	0x3
41
42#define CONTROL0_TSEN_START		BIT(0)
43#define CONTROL0_TSEN_RESET		BIT(1)
44#define CONTROL0_TSEN_ENABLE		BIT(2)
45#define CONTROL0_TSEN_AVG_BYPASS	BIT(6)
46#define CONTROL0_TSEN_CHAN_SHIFT	13
47#define CONTROL0_TSEN_CHAN_MASK		0xF
48#define CONTROL0_TSEN_OSR_SHIFT		24
49#define CONTROL0_TSEN_OSR_MAX		0x3
50#define CONTROL0_TSEN_MODE_SHIFT	30
51#define CONTROL0_TSEN_MODE_EXTERNAL	0x2
52#define CONTROL0_TSEN_MODE_MASK		0x3
53
54#define CONTROL1_TSEN_AVG_MASK		0x7
55#define CONTROL1_EXT_TSEN_SW_RESET	BIT(7)
56#define CONTROL1_EXT_TSEN_HW_RESETn	BIT(8)
57#define CONTROL1_TSEN_INT_EN		BIT(25)
58#define CONTROL1_TSEN_SELECT_OFF	21
59#define CONTROL1_TSEN_SELECT_MASK	0x3
60
61#define STATUS_POLL_PERIOD_US		1000
62#define STATUS_POLL_TIMEOUT_US		100000
63#define OVERHEAT_INT_POLL_DELAY_MS	1000
64
65struct armada_thermal_data;
66
67/* Marvell EBU Thermal Sensor Dev Structure */
68struct armada_thermal_priv {
69	struct device *dev;
70	struct regmap *syscon;
71	char zone_name[THERMAL_NAME_LENGTH];
72	/* serialize temperature reads/updates */
73	struct mutex update_lock;
74	struct armada_thermal_data *data;
75	struct thermal_zone_device *overheat_sensor;
76	int interrupt_source;
77	int current_channel;
78	long current_threshold;
79	long current_hysteresis;
80};
81
82struct armada_thermal_data {
83	/* Initialize the thermal IC */
84	void (*init)(struct platform_device *pdev,
85		     struct armada_thermal_priv *priv);
86
87	/* Formula coeficients: temp = (b - m * reg) / div */
88	s64 coef_b;
89	s64 coef_m;
90	u32 coef_div;
91	bool inverted;
92	bool signed_sample;
93
94	/* Register shift and mask to access the sensor temperature */
95	unsigned int temp_shift;
96	unsigned int temp_mask;
97	unsigned int thresh_shift;
98	unsigned int hyst_shift;
99	unsigned int hyst_mask;
100	u32 is_valid_bit;
101
102	/* Syscon access */
103	unsigned int syscon_control0_off;
104	unsigned int syscon_control1_off;
105	unsigned int syscon_status_off;
106	unsigned int dfx_irq_cause_off;
107	unsigned int dfx_irq_mask_off;
108	unsigned int dfx_overheat_irq;
109	unsigned int dfx_server_irq_mask_off;
110	unsigned int dfx_server_irq_en;
111
112	/* One sensor is in the thermal IC, the others are in the CPUs if any */
113	unsigned int cpu_nr;
114};
115
116struct armada_drvdata {
117	enum drvtype {
118		LEGACY,
119		SYSCON
120	} type;
121	union {
122		struct armada_thermal_priv *priv;
123		struct thermal_zone_device *tz;
124	} data;
125};
126
127/*
128 * struct armada_thermal_sensor - hold the information of one thermal sensor
129 * @thermal: pointer to the local private structure
130 * @tzd: pointer to the thermal zone device
131 * @id: identifier of the thermal sensor
132 */
133struct armada_thermal_sensor {
134	struct armada_thermal_priv *priv;
135	int id;
136};
137
138static void armadaxp_init(struct platform_device *pdev,
139			  struct armada_thermal_priv *priv)
140{
141	struct armada_thermal_data *data = priv->data;
142	u32 reg;
143
144	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
145	reg |= PMU_TDC0_OTF_CAL_MASK;
146
147	/* Reference calibration value */
148	reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
149	reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
150
151	/* Reset the sensor */
152	reg |= PMU_TDC0_SW_RST_MASK;
153
154	regmap_write(priv->syscon, data->syscon_control1_off, reg);
155
156	reg &= ~PMU_TDC0_SW_RST_MASK;
157	regmap_write(priv->syscon, data->syscon_control1_off, reg);
158
159	/* Enable the sensor */
160	regmap_read(priv->syscon, data->syscon_status_off, &reg);
161	reg &= ~PMU_TM_DISABLE_MASK;
162	regmap_write(priv->syscon, data->syscon_status_off, reg);
163}
164
165static void armada370_init(struct platform_device *pdev,
166			   struct armada_thermal_priv *priv)
167{
168	struct armada_thermal_data *data = priv->data;
169	u32 reg;
170
171	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
172	reg |= PMU_TDC0_OTF_CAL_MASK;
173
174	/* Reference calibration value */
175	reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
176	reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
177
178	/* Reset the sensor */
179	reg &= ~PMU_TDC0_START_CAL_MASK;
180
181	regmap_write(priv->syscon, data->syscon_control1_off, reg);
182
183	msleep(10);
184}
185
186static void armada375_init(struct platform_device *pdev,
187			   struct armada_thermal_priv *priv)
188{
189	struct armada_thermal_data *data = priv->data;
190	u32 reg;
191
192	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
193	reg &= ~(A375_UNIT_CONTROL_MASK << A375_UNIT_CONTROL_SHIFT);
194	reg &= ~A375_READOUT_INVERT;
195	reg &= ~A375_HW_RESETn;
196	regmap_write(priv->syscon, data->syscon_control1_off, reg);
197
198	msleep(20);
199
200	reg |= A375_HW_RESETn;
201	regmap_write(priv->syscon, data->syscon_control1_off, reg);
202
203	msleep(50);
204}
205
206static int armada_wait_sensor_validity(struct armada_thermal_priv *priv)
207{
208	u32 reg;
209
210	return regmap_read_poll_timeout(priv->syscon,
211					priv->data->syscon_status_off, reg,
212					reg & priv->data->is_valid_bit,
213					STATUS_POLL_PERIOD_US,
214					STATUS_POLL_TIMEOUT_US);
215}
216
217static void armada380_init(struct platform_device *pdev,
218			   struct armada_thermal_priv *priv)
219{
220	struct armada_thermal_data *data = priv->data;
221	u32 reg;
222
223	/* Disable the HW/SW reset */
224	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
225	reg |= CONTROL1_EXT_TSEN_HW_RESETn;
226	reg &= ~CONTROL1_EXT_TSEN_SW_RESET;
227	regmap_write(priv->syscon, data->syscon_control1_off, reg);
228
229	/* Set Tsen Tc Trim to correct default value (errata #132698) */
230	regmap_read(priv->syscon, data->syscon_control0_off, &reg);
231	reg &= ~CONTROL0_TSEN_TC_TRIM_MASK;
232	reg |= CONTROL0_TSEN_TC_TRIM_VAL;
233	regmap_write(priv->syscon, data->syscon_control0_off, reg);
234}
235
236static void armada_ap806_init(struct platform_device *pdev,
237			      struct armada_thermal_priv *priv)
238{
239	struct armada_thermal_data *data = priv->data;
240	u32 reg;
241
242	regmap_read(priv->syscon, data->syscon_control0_off, &reg);
243	reg &= ~CONTROL0_TSEN_RESET;
244	reg |= CONTROL0_TSEN_START | CONTROL0_TSEN_ENABLE;
245
246	/* Sample every ~2ms */
247	reg |= CONTROL0_TSEN_OSR_MAX << CONTROL0_TSEN_OSR_SHIFT;
248
249	/* Enable average (2 samples by default) */
250	reg &= ~CONTROL0_TSEN_AVG_BYPASS;
251
252	regmap_write(priv->syscon, data->syscon_control0_off, reg);
253}
254
255static void armada_cp110_init(struct platform_device *pdev,
256			      struct armada_thermal_priv *priv)
257{
258	struct armada_thermal_data *data = priv->data;
259	u32 reg;
260
261	armada380_init(pdev, priv);
262
263	/* Sample every ~2ms */
264	regmap_read(priv->syscon, data->syscon_control0_off, &reg);
265	reg |= CONTROL0_TSEN_OSR_MAX << CONTROL0_TSEN_OSR_SHIFT;
266	regmap_write(priv->syscon, data->syscon_control0_off, reg);
267
268	/* Average the output value over 2^1 = 2 samples */
269	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
270	reg &= ~CONTROL1_TSEN_AVG_MASK;
271	reg |= 1;
272	regmap_write(priv->syscon, data->syscon_control1_off, reg);
273}
274
275static bool armada_is_valid(struct armada_thermal_priv *priv)
276{
277	u32 reg;
278
279	if (!priv->data->is_valid_bit)
280		return true;
281
282	regmap_read(priv->syscon, priv->data->syscon_status_off, &reg);
283
284	return reg & priv->data->is_valid_bit;
285}
286
287static void armada_enable_overheat_interrupt(struct armada_thermal_priv *priv)
288{
289	struct armada_thermal_data *data = priv->data;
290	u32 reg;
291
292	/* Clear DFX temperature IRQ cause */
293	regmap_read(priv->syscon, data->dfx_irq_cause_off, &reg);
294
295	/* Enable DFX Temperature IRQ */
296	regmap_read(priv->syscon, data->dfx_irq_mask_off, &reg);
297	reg |= data->dfx_overheat_irq;
298	regmap_write(priv->syscon, data->dfx_irq_mask_off, reg);
299
300	/* Enable DFX server IRQ */
301	regmap_read(priv->syscon, data->dfx_server_irq_mask_off, &reg);
302	reg |= data->dfx_server_irq_en;
303	regmap_write(priv->syscon, data->dfx_server_irq_mask_off, reg);
304
305	/* Enable overheat interrupt */
306	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
307	reg |= CONTROL1_TSEN_INT_EN;
308	regmap_write(priv->syscon, data->syscon_control1_off, reg);
309}
310
311static void __maybe_unused
312armada_disable_overheat_interrupt(struct armada_thermal_priv *priv)
313{
314	struct armada_thermal_data *data = priv->data;
315	u32 reg;
316
317	regmap_read(priv->syscon, data->syscon_control1_off, &reg);
318	reg &= ~CONTROL1_TSEN_INT_EN;
319	regmap_write(priv->syscon, data->syscon_control1_off, reg);
320}
321
322/* There is currently no board with more than one sensor per channel */
323static int armada_select_channel(struct armada_thermal_priv *priv, int channel)
324{
325	struct armada_thermal_data *data = priv->data;
326	u32 ctrl0;
327
328	if (channel < 0 || channel > priv->data->cpu_nr)
329		return -EINVAL;
330
331	if (priv->current_channel == channel)
332		return 0;
333
334	/* Stop the measurements */
335	regmap_read(priv->syscon, data->syscon_control0_off, &ctrl0);
336	ctrl0 &= ~CONTROL0_TSEN_START;
337	regmap_write(priv->syscon, data->syscon_control0_off, ctrl0);
338
339	/* Reset the mode, internal sensor will be automatically selected */
340	ctrl0 &= ~(CONTROL0_TSEN_MODE_MASK << CONTROL0_TSEN_MODE_SHIFT);
341
342	/* Other channels are external and should be selected accordingly */
343	if (channel) {
344		/* Change the mode to external */
345		ctrl0 |= CONTROL0_TSEN_MODE_EXTERNAL <<
346			 CONTROL0_TSEN_MODE_SHIFT;
347		/* Select the sensor */
348		ctrl0 &= ~(CONTROL0_TSEN_CHAN_MASK << CONTROL0_TSEN_CHAN_SHIFT);
349		ctrl0 |= (channel - 1) << CONTROL0_TSEN_CHAN_SHIFT;
350	}
351
352	/* Actually set the mode/channel */
353	regmap_write(priv->syscon, data->syscon_control0_off, ctrl0);
354	priv->current_channel = channel;
355
356	/* Re-start the measurements */
357	ctrl0 |= CONTROL0_TSEN_START;
358	regmap_write(priv->syscon, data->syscon_control0_off, ctrl0);
359
360	/*
361	 * The IP has a latency of ~15ms, so after updating the selected source,
362	 * we must absolutely wait for the sensor validity bit to ensure we read
363	 * actual data.
364	 */
365	if (armada_wait_sensor_validity(priv)) {
366		dev_err(priv->dev,
367			"Temperature sensor reading not valid\n");
368		return -EIO;
369	}
370
371	return 0;
372}
373
374static int armada_read_sensor(struct armada_thermal_priv *priv, int *temp)
375{
376	u32 reg, div;
377	s64 sample, b, m;
378
379	regmap_read(priv->syscon, priv->data->syscon_status_off, &reg);
380	reg = (reg >> priv->data->temp_shift) & priv->data->temp_mask;
381	if (priv->data->signed_sample)
382		/* The most significant bit is the sign bit */
383		sample = sign_extend32(reg, fls(priv->data->temp_mask) - 1);
384	else
385		sample = reg;
386
387	/* Get formula coeficients */
388	b = priv->data->coef_b;
389	m = priv->data->coef_m;
390	div = priv->data->coef_div;
391
392	if (priv->data->inverted)
393		*temp = div_s64((m * sample) - b, div);
394	else
395		*temp = div_s64(b - (m * sample), div);
396
397	return 0;
398}
399
400static int armada_get_temp_legacy(struct thermal_zone_device *thermal,
401				  int *temp)
402{
403	struct armada_thermal_priv *priv = thermal->devdata;
404	int ret;
405
406	/* Valid check */
407	if (!armada_is_valid(priv)) {
408		dev_err(priv->dev,
409			"Temperature sensor reading not valid\n");
410		return -EIO;
411	}
412
413	/* Do the actual reading */
414	ret = armada_read_sensor(priv, temp);
415
416	return ret;
417}
418
419static struct thermal_zone_device_ops legacy_ops = {
420	.get_temp = armada_get_temp_legacy,
421};
422
423static int armada_get_temp(void *_sensor, int *temp)
424{
425	struct armada_thermal_sensor *sensor = _sensor;
426	struct armada_thermal_priv *priv = sensor->priv;
427	int ret;
428
429	mutex_lock(&priv->update_lock);
430
431	/* Select the desired channel */
432	ret = armada_select_channel(priv, sensor->id);
433	if (ret)
434		goto unlock_mutex;
435
436	/* Do the actual reading */
437	ret = armada_read_sensor(priv, temp);
438	if (ret)
439		goto unlock_mutex;
440
441	/*
442	 * Select back the interrupt source channel from which a potential
443	 * critical trip point has been set.
444	 */
445	ret = armada_select_channel(priv, priv->interrupt_source);
446
447unlock_mutex:
448	mutex_unlock(&priv->update_lock);
449
450	return ret;
451}
452
453static const struct thermal_zone_of_device_ops of_ops = {
454	.get_temp = armada_get_temp,
455};
456
457static unsigned int armada_mc_to_reg_temp(struct armada_thermal_data *data,
458					  unsigned int temp_mc)
459{
460	s64 b = data->coef_b;
461	s64 m = data->coef_m;
462	s64 div = data->coef_div;
463	unsigned int sample;
464
465	if (data->inverted)
466		sample = div_s64(((temp_mc * div) + b), m);
467	else
468		sample = div_s64((b - (temp_mc * div)), m);
469
470	return sample & data->temp_mask;
471}
472
473/*
474 * The documentation states:
475 * high/low watermark = threshold +/- 0.4761 * 2^(hysteresis + 2)
476 * which is the mathematical derivation for:
477 * 0x0 <=> 1.9°C, 0x1 <=> 3.8°C, 0x2 <=> 7.6°C, 0x3 <=> 15.2°C
478 */
479static unsigned int hyst_levels_mc[] = {1900, 3800, 7600, 15200};
480
481static unsigned int armada_mc_to_reg_hyst(struct armada_thermal_data *data,
482					  unsigned int hyst_mc)
483{
484	int i;
485
486	/*
487	 * We will always take the smallest possible hysteresis to avoid risking
488	 * the hardware integrity by enlarging the threshold by +8°C in the
489	 * worst case.
490	 */
491	for (i = ARRAY_SIZE(hyst_levels_mc) - 1; i > 0; i--)
492		if (hyst_mc >= hyst_levels_mc[i])
493			break;
494
495	return i & data->hyst_mask;
496}
497
498static void armada_set_overheat_thresholds(struct armada_thermal_priv *priv,
499					   int thresh_mc, int hyst_mc)
500{
501	struct armada_thermal_data *data = priv->data;
502	unsigned int threshold = armada_mc_to_reg_temp(data, thresh_mc);
503	unsigned int hysteresis = armada_mc_to_reg_hyst(data, hyst_mc);
504	u32 ctrl1;
505
506	regmap_read(priv->syscon, data->syscon_control1_off, &ctrl1);
507
508	/* Set Threshold */
509	if (thresh_mc >= 0) {
510		ctrl1 &= ~(data->temp_mask << data->thresh_shift);
511		ctrl1 |= threshold << data->thresh_shift;
512		priv->current_threshold = thresh_mc;
513	}
514
515	/* Set Hysteresis */
516	if (hyst_mc >= 0) {
517		ctrl1 &= ~(data->hyst_mask << data->hyst_shift);
518		ctrl1 |= hysteresis << data->hyst_shift;
519		priv->current_hysteresis = hyst_mc;
520	}
521
522	regmap_write(priv->syscon, data->syscon_control1_off, ctrl1);
523}
524
525static irqreturn_t armada_overheat_isr(int irq, void *blob)
526{
527	/*
528	 * Disable the IRQ and continue in thread context (thermal core
529	 * notification and temperature monitoring).
530	 */
531	disable_irq_nosync(irq);
532
533	return IRQ_WAKE_THREAD;
534}
535
536static irqreturn_t armada_overheat_isr_thread(int irq, void *blob)
537{
538	struct armada_thermal_priv *priv = blob;
539	int low_threshold = priv->current_threshold - priv->current_hysteresis;
540	int temperature;
541	u32 dummy;
542	int ret;
543
544	/* Notify the core in thread context */
545	thermal_zone_device_update(priv->overheat_sensor,
546				   THERMAL_EVENT_UNSPECIFIED);
547
548	/*
549	 * The overheat interrupt must be cleared by reading the DFX interrupt
550	 * cause _after_ the temperature has fallen down to the low threshold.
551	 * Otherwise future interrupts might not be served.
552	 */
553	do {
554		msleep(OVERHEAT_INT_POLL_DELAY_MS);
555		mutex_lock(&priv->update_lock);
556		ret = armada_read_sensor(priv, &temperature);
557		mutex_unlock(&priv->update_lock);
558		if (ret)
559			goto enable_irq;
560	} while (temperature >= low_threshold);
561
562	regmap_read(priv->syscon, priv->data->dfx_irq_cause_off, &dummy);
563
564	/* Notify the thermal core that the temperature is acceptable again */
565	thermal_zone_device_update(priv->overheat_sensor,
566				   THERMAL_EVENT_UNSPECIFIED);
567
568enable_irq:
569	enable_irq(irq);
570
571	return IRQ_HANDLED;
572}
573
574static const struct armada_thermal_data armadaxp_data = {
575	.init = armadaxp_init,
576	.temp_shift = 10,
577	.temp_mask = 0x1ff,
578	.coef_b = 3153000000ULL,
579	.coef_m = 10000000ULL,
580	.coef_div = 13825,
581	.syscon_status_off = 0xb0,
582	.syscon_control1_off = 0x2d0,
583};
584
585static const struct armada_thermal_data armada370_data = {
586	.init = armada370_init,
587	.is_valid_bit = BIT(9),
588	.temp_shift = 10,
589	.temp_mask = 0x1ff,
590	.coef_b = 3153000000ULL,
591	.coef_m = 10000000ULL,
592	.coef_div = 13825,
593	.syscon_status_off = 0x0,
594	.syscon_control1_off = 0x4,
595};
596
597static const struct armada_thermal_data armada375_data = {
598	.init = armada375_init,
599	.is_valid_bit = BIT(10),
600	.temp_shift = 0,
601	.temp_mask = 0x1ff,
602	.coef_b = 3171900000ULL,
603	.coef_m = 10000000ULL,
604	.coef_div = 13616,
605	.syscon_status_off = 0x78,
606	.syscon_control0_off = 0x7c,
607	.syscon_control1_off = 0x80,
608};
609
610static const struct armada_thermal_data armada380_data = {
611	.init = armada380_init,
612	.is_valid_bit = BIT(10),
613	.temp_shift = 0,
614	.temp_mask = 0x3ff,
615	.coef_b = 1172499100ULL,
616	.coef_m = 2000096ULL,
617	.coef_div = 4201,
618	.inverted = true,
619	.syscon_control0_off = 0x70,
620	.syscon_control1_off = 0x74,
621	.syscon_status_off = 0x78,
622};
623
624static const struct armada_thermal_data armada_ap806_data = {
625	.init = armada_ap806_init,
626	.is_valid_bit = BIT(16),
627	.temp_shift = 0,
628	.temp_mask = 0x3ff,
629	.thresh_shift = 3,
630	.hyst_shift = 19,
631	.hyst_mask = 0x3,
632	.coef_b = -150000LL,
633	.coef_m = 423ULL,
634	.coef_div = 1,
635	.inverted = true,
636	.signed_sample = true,
637	.syscon_control0_off = 0x84,
638	.syscon_control1_off = 0x88,
639	.syscon_status_off = 0x8C,
640	.dfx_irq_cause_off = 0x108,
641	.dfx_irq_mask_off = 0x10C,
642	.dfx_overheat_irq = BIT(22),
643	.dfx_server_irq_mask_off = 0x104,
644	.dfx_server_irq_en = BIT(1),
645	.cpu_nr = 4,
646};
647
648static const struct armada_thermal_data armada_cp110_data = {
649	.init = armada_cp110_init,
650	.is_valid_bit = BIT(10),
651	.temp_shift = 0,
652	.temp_mask = 0x3ff,
653	.thresh_shift = 16,
654	.hyst_shift = 26,
655	.hyst_mask = 0x3,
656	.coef_b = 1172499100ULL,
657	.coef_m = 2000096ULL,
658	.coef_div = 4201,
659	.inverted = true,
660	.syscon_control0_off = 0x70,
661	.syscon_control1_off = 0x74,
662	.syscon_status_off = 0x78,
663	.dfx_irq_cause_off = 0x108,
664	.dfx_irq_mask_off = 0x10C,
665	.dfx_overheat_irq = BIT(20),
666	.dfx_server_irq_mask_off = 0x104,
667	.dfx_server_irq_en = BIT(1),
668};
669
670static const struct of_device_id armada_thermal_id_table[] = {
671	{
672		.compatible = "marvell,armadaxp-thermal",
673		.data       = &armadaxp_data,
674	},
675	{
676		.compatible = "marvell,armada370-thermal",
677		.data       = &armada370_data,
678	},
679	{
680		.compatible = "marvell,armada375-thermal",
681		.data       = &armada375_data,
682	},
683	{
684		.compatible = "marvell,armada380-thermal",
685		.data       = &armada380_data,
686	},
687	{
688		.compatible = "marvell,armada-ap806-thermal",
689		.data       = &armada_ap806_data,
690	},
691	{
692		.compatible = "marvell,armada-cp110-thermal",
693		.data       = &armada_cp110_data,
694	},
695	{
696		/* sentinel */
697	},
698};
699MODULE_DEVICE_TABLE(of, armada_thermal_id_table);
700
701static const struct regmap_config armada_thermal_regmap_config = {
702	.reg_bits = 32,
703	.reg_stride = 4,
704	.val_bits = 32,
705	.fast_io = true,
706};
707
708static int armada_thermal_probe_legacy(struct platform_device *pdev,
709				       struct armada_thermal_priv *priv)
710{
711	struct armada_thermal_data *data = priv->data;
712	struct resource *res;
713	void __iomem *base;
714
715	/* First memory region points towards the status register */
716	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
717	base = devm_ioremap_resource(&pdev->dev, res);
718	if (IS_ERR(base))
719		return PTR_ERR(base);
720
721	/*
722	 * Fix up from the old individual DT register specification to
723	 * cover all the registers.  We do this by adjusting the ioremap()
724	 * result, which should be fine as ioremap() deals with pages.
725	 * However, validate that we do not cross a page boundary while
726	 * making this adjustment.
727	 */
728	if (((unsigned long)base & ~PAGE_MASK) < data->syscon_status_off)
729		return -EINVAL;
730	base -= data->syscon_status_off;
731
732	priv->syscon = devm_regmap_init_mmio(&pdev->dev, base,
733					     &armada_thermal_regmap_config);
734	return PTR_ERR_OR_ZERO(priv->syscon);
735}
736
737static int armada_thermal_probe_syscon(struct platform_device *pdev,
738				       struct armada_thermal_priv *priv)
739{
740	priv->syscon = syscon_node_to_regmap(pdev->dev.parent->of_node);
741	return PTR_ERR_OR_ZERO(priv->syscon);
742}
743
744static void armada_set_sane_name(struct platform_device *pdev,
745				 struct armada_thermal_priv *priv)
746{
747	const char *name = dev_name(&pdev->dev);
748	char *insane_char;
749
750	if (strlen(name) > THERMAL_NAME_LENGTH) {
751		/*
752		 * When inside a system controller, the device name has the
753		 * form: f06f8000.system-controller:ap-thermal so stripping
754		 * after the ':' should give us a shorter but meaningful name.
755		 */
756		name = strrchr(name, ':');
757		if (!name)
758			name = "armada_thermal";
759		else
760			name++;
761	}
762
763	/* Save the name locally */
764	strncpy(priv->zone_name, name, THERMAL_NAME_LENGTH - 1);
765	priv->zone_name[THERMAL_NAME_LENGTH - 1] = '\0';
766
767	/* Then check there are no '-' or hwmon core will complain */
768	do {
769		insane_char = strpbrk(priv->zone_name, "-");
770		if (insane_char)
771			*insane_char = '_';
772	} while (insane_char);
773}
774
775/*
776 * The IP can manage to trigger interrupts on overheat situation from all the
777 * sensors. However, the interrupt source changes along with the last selected
778 * source (ie. the last read sensor), which is an inconsistent behavior. Avoid
779 * possible glitches by always selecting back only one channel (arbitrarily: the
780 * first in the DT which has a critical trip point). We also disable sensor
781 * switch during overheat situations.
782 */
783static int armada_configure_overheat_int(struct armada_thermal_priv *priv,
784					 struct thermal_zone_device *tz,
785					 int sensor_id)
786{
787	/* Retrieve the critical trip point to enable the overheat interrupt */
788	const struct thermal_trip *trips = of_thermal_get_trip_points(tz);
789	int ret;
790	int i;
791
792	if (!trips)
793		return -EINVAL;
794
795	for (i = 0; i < of_thermal_get_ntrips(tz); i++)
796		if (trips[i].type == THERMAL_TRIP_CRITICAL)
797			break;
798
799	if (i == of_thermal_get_ntrips(tz))
800		return -EINVAL;
801
802	ret = armada_select_channel(priv, sensor_id);
803	if (ret)
804		return ret;
805
806	armada_set_overheat_thresholds(priv,
807				       trips[i].temperature,
808				       trips[i].hysteresis);
809	priv->overheat_sensor = tz;
810	priv->interrupt_source = sensor_id;
811
812	armada_enable_overheat_interrupt(priv);
813
814	return 0;
815}
816
817static int armada_thermal_probe(struct platform_device *pdev)
818{
819	struct thermal_zone_device *tz;
820	struct armada_thermal_sensor *sensor;
821	struct armada_drvdata *drvdata;
822	const struct of_device_id *match;
823	struct armada_thermal_priv *priv;
824	int sensor_id, irq;
825	int ret;
826
827	match = of_match_device(armada_thermal_id_table, &pdev->dev);
828	if (!match)
829		return -ENODEV;
830
831	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
832	if (!priv)
833		return -ENOMEM;
834
835	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
836	if (!drvdata)
837		return -ENOMEM;
838
839	priv->dev = &pdev->dev;
840	priv->data = (struct armada_thermal_data *)match->data;
841
842	mutex_init(&priv->update_lock);
843
844	/*
845	 * Legacy DT bindings only described "control1" register (also referred
846	 * as "control MSB" on old documentation). Then, bindings moved to cover
847	 * "control0/control LSB" and "control1/control MSB" registers within
848	 * the same resource, which was then of size 8 instead of 4.
849	 *
850	 * The logic of defining sporadic registers is broken. For instance, it
851	 * blocked the addition of the overheat interrupt feature that needed
852	 * another resource somewhere else in the same memory area. One solution
853	 * is to define an overall system controller and put the thermal node
854	 * into it, which requires the use of regmaps across all the driver.
855	 */
856	if (IS_ERR(syscon_node_to_regmap(pdev->dev.parent->of_node))) {
857		/* Ensure device name is correct for the thermal core */
858		armada_set_sane_name(pdev, priv);
859
860		ret = armada_thermal_probe_legacy(pdev, priv);
861		if (ret)
862			return ret;
863
864		priv->data->init(pdev, priv);
865
866		/* Wait the sensors to be valid */
867		armada_wait_sensor_validity(priv);
868
869		tz = thermal_zone_device_register(priv->zone_name, 0, 0, priv,
870						  &legacy_ops, NULL, 0, 0);
871		if (IS_ERR(tz)) {
872			dev_err(&pdev->dev,
873				"Failed to register thermal zone device\n");
874			return PTR_ERR(tz);
875		}
876
877		ret = thermal_zone_device_enable(tz);
878		if (ret) {
879			thermal_zone_device_unregister(tz);
880			return ret;
881		}
882
883		drvdata->type = LEGACY;
884		drvdata->data.tz = tz;
885		platform_set_drvdata(pdev, drvdata);
886
887		return 0;
888	}
889
890	ret = armada_thermal_probe_syscon(pdev, priv);
891	if (ret)
892		return ret;
893
894	priv->current_channel = -1;
895	priv->data->init(pdev, priv);
896	drvdata->type = SYSCON;
897	drvdata->data.priv = priv;
898	platform_set_drvdata(pdev, drvdata);
899
900	irq = platform_get_irq(pdev, 0);
901	if (irq == -EPROBE_DEFER)
902		return irq;
903
904	/* The overheat interrupt feature is not mandatory */
905	if (irq > 0) {
906		ret = devm_request_threaded_irq(&pdev->dev, irq,
907						armada_overheat_isr,
908						armada_overheat_isr_thread,
909						0, NULL, priv);
910		if (ret) {
911			dev_err(&pdev->dev, "Cannot request threaded IRQ %d\n",
912				irq);
913			return ret;
914		}
915	}
916
917	/*
918	 * There is one channel for the IC and one per CPU (if any), each
919	 * channel has one sensor.
920	 */
921	for (sensor_id = 0; sensor_id <= priv->data->cpu_nr; sensor_id++) {
922		sensor = devm_kzalloc(&pdev->dev,
923				      sizeof(struct armada_thermal_sensor),
924				      GFP_KERNEL);
925		if (!sensor)
926			return -ENOMEM;
927
928		/* Register the sensor */
929		sensor->priv = priv;
930		sensor->id = sensor_id;
931		tz = devm_thermal_zone_of_sensor_register(&pdev->dev,
932							  sensor->id, sensor,
933							  &of_ops);
934		if (IS_ERR(tz)) {
935			dev_info(&pdev->dev, "Thermal sensor %d unavailable\n",
936				 sensor_id);
937			devm_kfree(&pdev->dev, sensor);
938			continue;
939		}
940
941		/*
942		 * The first channel that has a critical trip point registered
943		 * in the DT will serve as interrupt source. Others possible
944		 * critical trip points will simply be ignored by the driver.
945		 */
946		if (irq > 0 && !priv->overheat_sensor)
947			armada_configure_overheat_int(priv, tz, sensor->id);
948	}
949
950	/* Just complain if no overheat interrupt was set up */
951	if (!priv->overheat_sensor)
952		dev_warn(&pdev->dev, "Overheat interrupt not available\n");
953
954	return 0;
955}
956
957static int armada_thermal_exit(struct platform_device *pdev)
958{
959	struct armada_drvdata *drvdata = platform_get_drvdata(pdev);
960
961	if (drvdata->type == LEGACY)
962		thermal_zone_device_unregister(drvdata->data.tz);
963
964	return 0;
965}
966
967static struct platform_driver armada_thermal_driver = {
968	.probe = armada_thermal_probe,
969	.remove = armada_thermal_exit,
970	.driver = {
971		.name = "armada_thermal",
972		.of_match_table = armada_thermal_id_table,
973	},
974};
975
976module_platform_driver(armada_thermal_driver);
977
978MODULE_AUTHOR("Ezequiel Garcia <ezequiel.garcia@free-electrons.com>");
979MODULE_DESCRIPTION("Marvell EBU Armada SoCs thermal driver");
980MODULE_LICENSE("GPL v2");
981