xref: /openbmc/linux/drivers/soc/qcom/icc-bwmon.c (revision 2f164822)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2014-2018, The Linux Foundation. All rights reserved.
4  * Copyright (C) 2021-2022 Linaro Ltd
5  * Author: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>, based on
6  *         previous work of Thara Gopinath and msm-4.9 downstream sources.
7  */
8 
9 #include <linux/err.h>
10 #include <linux/interconnect.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/of_device.h>
16 #include <linux/platform_device.h>
17 #include <linux/pm_opp.h>
18 #include <linux/regmap.h>
19 #include <linux/sizes.h>
20 
21 /*
22  * The BWMON samples data throughput within 'sample_ms' time. With three
23  * configurable thresholds (Low, Medium and High) gives four windows (called
24  * zones) of current bandwidth:
25  *
26  * Zone 0: byte count < THRES_LO
27  * Zone 1: THRES_LO < byte count < THRES_MED
28  * Zone 2: THRES_MED < byte count < THRES_HIGH
29  * Zone 3: THRES_HIGH < byte count
30  *
31  * Zones 0 and 2 are not used by this driver.
32  */
33 
34 /* Internal sampling clock frequency */
35 #define HW_TIMER_HZ				19200000
36 
37 #define BWMON_V4_GLOBAL_IRQ_CLEAR		0x008
38 #define BWMON_V4_GLOBAL_IRQ_ENABLE		0x00c
39 /*
40  * All values here and further are matching regmap fields, so without absolute
41  * register offsets.
42  */
43 #define BWMON_V4_GLOBAL_IRQ_ENABLE_ENABLE	BIT(0)
44 
45 #define BWMON_V4_IRQ_STATUS			0x100
46 #define BWMON_V4_IRQ_CLEAR			0x108
47 
48 #define BWMON_V4_IRQ_ENABLE			0x10c
49 #define BWMON_IRQ_ENABLE_MASK			(BIT(1) | BIT(3))
50 #define BWMON_V5_IRQ_STATUS			0x000
51 #define BWMON_V5_IRQ_CLEAR			0x008
52 #define BWMON_V5_IRQ_ENABLE			0x00c
53 
54 #define BWMON_V4_ENABLE				0x2a0
55 #define BWMON_V5_ENABLE				0x010
56 #define BWMON_ENABLE_ENABLE			BIT(0)
57 
58 #define BWMON_V4_CLEAR				0x2a4
59 #define BWMON_V5_CLEAR				0x014
60 #define BWMON_CLEAR_CLEAR			BIT(0)
61 #define BWMON_CLEAR_CLEAR_ALL			BIT(1)
62 
63 #define BWMON_V4_SAMPLE_WINDOW			0x2a8
64 #define BWMON_V5_SAMPLE_WINDOW			0x020
65 
66 #define BWMON_V4_THRESHOLD_HIGH			0x2ac
67 #define BWMON_V4_THRESHOLD_MED			0x2b0
68 #define BWMON_V4_THRESHOLD_LOW			0x2b4
69 #define BWMON_V5_THRESHOLD_HIGH			0x024
70 #define BWMON_V5_THRESHOLD_MED			0x028
71 #define BWMON_V5_THRESHOLD_LOW			0x02c
72 
73 #define BWMON_V4_ZONE_ACTIONS			0x2b8
74 #define BWMON_V5_ZONE_ACTIONS			0x030
75 /*
76  * Actions to perform on some zone 'z' when current zone hits the threshold:
77  * Increment counter of zone 'z'
78  */
79 #define BWMON_ZONE_ACTIONS_INCREMENT(z)		(0x2 << ((z) * 2))
80 /* Clear counter of zone 'z' */
81 #define BWMON_ZONE_ACTIONS_CLEAR(z)		(0x1 << ((z) * 2))
82 
83 /* Zone 0 threshold hit: Clear zone count */
84 #define BWMON_ZONE_ACTIONS_ZONE0		(BWMON_ZONE_ACTIONS_CLEAR(0))
85 
86 /* Zone 1 threshold hit: Increment zone count & clear lower zones */
87 #define BWMON_ZONE_ACTIONS_ZONE1		(BWMON_ZONE_ACTIONS_INCREMENT(1) | \
88 						 BWMON_ZONE_ACTIONS_CLEAR(0))
89 
90 /* Zone 2 threshold hit: Increment zone count & clear lower zones */
91 #define BWMON_ZONE_ACTIONS_ZONE2		(BWMON_ZONE_ACTIONS_INCREMENT(2) | \
92 						 BWMON_ZONE_ACTIONS_CLEAR(1) | \
93 						 BWMON_ZONE_ACTIONS_CLEAR(0))
94 
95 /* Zone 3 threshold hit: Increment zone count & clear lower zones */
96 #define BWMON_ZONE_ACTIONS_ZONE3		(BWMON_ZONE_ACTIONS_INCREMENT(3) | \
97 						 BWMON_ZONE_ACTIONS_CLEAR(2) | \
98 						 BWMON_ZONE_ACTIONS_CLEAR(1) | \
99 						 BWMON_ZONE_ACTIONS_CLEAR(0))
100 
101 /*
102  * There is no clear documentation/explanation of BWMON_V4_THRESHOLD_COUNT
103  * register. Based on observations, this is number of times one threshold has to
104  * be reached, to trigger interrupt in given zone.
105  *
106  * 0xff are maximum values meant to ignore the zones 0 and 2.
107  */
108 #define BWMON_V4_THRESHOLD_COUNT		0x2bc
109 #define BWMON_V5_THRESHOLD_COUNT		0x034
110 #define BWMON_THRESHOLD_COUNT_ZONE0_DEFAULT	0xff
111 #define BWMON_THRESHOLD_COUNT_ZONE2_DEFAULT	0xff
112 
113 #define BWMON_V4_ZONE_MAX(zone)			(0x2e0 + 4 * (zone))
114 #define BWMON_V5_ZONE_MAX(zone)			(0x044 + 4 * (zone))
115 
116 /* Quirks for specific BWMON types */
117 #define BWMON_HAS_GLOBAL_IRQ			BIT(0)
118 #define BWMON_NEEDS_FORCE_CLEAR			BIT(1)
119 
120 enum bwmon_fields {
121 	F_GLOBAL_IRQ_CLEAR,
122 	F_GLOBAL_IRQ_ENABLE,
123 	F_IRQ_STATUS,
124 	F_IRQ_CLEAR,
125 	F_IRQ_ENABLE,
126 	F_ENABLE,
127 	F_CLEAR,
128 	F_SAMPLE_WINDOW,
129 	F_THRESHOLD_HIGH,
130 	F_THRESHOLD_MED,
131 	F_THRESHOLD_LOW,
132 	F_ZONE_ACTIONS_ZONE0,
133 	F_ZONE_ACTIONS_ZONE1,
134 	F_ZONE_ACTIONS_ZONE2,
135 	F_ZONE_ACTIONS_ZONE3,
136 	F_THRESHOLD_COUNT_ZONE0,
137 	F_THRESHOLD_COUNT_ZONE1,
138 	F_THRESHOLD_COUNT_ZONE2,
139 	F_THRESHOLD_COUNT_ZONE3,
140 	F_ZONE0_MAX,
141 	F_ZONE1_MAX,
142 	F_ZONE2_MAX,
143 	F_ZONE3_MAX,
144 
145 	F_NUM_FIELDS
146 };
147 
148 struct icc_bwmon_data {
149 	unsigned int sample_ms;
150 	unsigned int count_unit_kb; /* kbytes */
151 	unsigned int default_highbw_kbps;
152 	unsigned int default_medbw_kbps;
153 	unsigned int default_lowbw_kbps;
154 	u8 zone1_thres_count;
155 	u8 zone3_thres_count;
156 	unsigned int quirks;
157 
158 	const struct regmap_config *regmap_cfg;
159 	const struct reg_field *regmap_fields;
160 };
161 
162 struct icc_bwmon {
163 	struct device *dev;
164 	const struct icc_bwmon_data *data;
165 	int irq;
166 
167 	struct regmap *regmap;
168 	struct regmap_field *regs[F_NUM_FIELDS];
169 
170 	unsigned int max_bw_kbps;
171 	unsigned int min_bw_kbps;
172 	unsigned int target_kbps;
173 	unsigned int current_kbps;
174 };
175 
176 /* BWMON v4 */
177 static const struct reg_field msm8998_bwmon_reg_fields[] = {
178 	[F_GLOBAL_IRQ_CLEAR]	= REG_FIELD(BWMON_V4_GLOBAL_IRQ_CLEAR, 0, 0),
179 	[F_GLOBAL_IRQ_ENABLE]	= REG_FIELD(BWMON_V4_GLOBAL_IRQ_ENABLE, 0, 0),
180 	[F_IRQ_STATUS]		= REG_FIELD(BWMON_V4_IRQ_STATUS, 4, 7),
181 	[F_IRQ_CLEAR]		= REG_FIELD(BWMON_V4_IRQ_CLEAR, 4, 7),
182 	[F_IRQ_ENABLE]		= REG_FIELD(BWMON_V4_IRQ_ENABLE, 4, 7),
183 	/* F_ENABLE covers entire register to disable other features */
184 	[F_ENABLE]		= REG_FIELD(BWMON_V4_ENABLE, 0, 31),
185 	[F_CLEAR]		= REG_FIELD(BWMON_V4_CLEAR, 0, 1),
186 	[F_SAMPLE_WINDOW]	= REG_FIELD(BWMON_V4_SAMPLE_WINDOW, 0, 23),
187 	[F_THRESHOLD_HIGH]	= REG_FIELD(BWMON_V4_THRESHOLD_HIGH, 0, 11),
188 	[F_THRESHOLD_MED]	= REG_FIELD(BWMON_V4_THRESHOLD_MED, 0, 11),
189 	[F_THRESHOLD_LOW]	= REG_FIELD(BWMON_V4_THRESHOLD_LOW, 0, 11),
190 	[F_ZONE_ACTIONS_ZONE0]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 0, 7),
191 	[F_ZONE_ACTIONS_ZONE1]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 8, 15),
192 	[F_ZONE_ACTIONS_ZONE2]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 16, 23),
193 	[F_ZONE_ACTIONS_ZONE3]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 24, 31),
194 	[F_THRESHOLD_COUNT_ZONE0]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 0, 7),
195 	[F_THRESHOLD_COUNT_ZONE1]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 8, 15),
196 	[F_THRESHOLD_COUNT_ZONE2]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 16, 23),
197 	[F_THRESHOLD_COUNT_ZONE3]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 24, 31),
198 	[F_ZONE0_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(0), 0, 11),
199 	[F_ZONE1_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(1), 0, 11),
200 	[F_ZONE2_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(2), 0, 11),
201 	[F_ZONE3_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(3), 0, 11),
202 };
203 
204 static const struct regmap_range msm8998_bwmon_reg_noread_ranges[] = {
205 	regmap_reg_range(BWMON_V4_GLOBAL_IRQ_CLEAR, BWMON_V4_GLOBAL_IRQ_CLEAR),
206 	regmap_reg_range(BWMON_V4_IRQ_CLEAR, BWMON_V4_IRQ_CLEAR),
207 	regmap_reg_range(BWMON_V4_CLEAR, BWMON_V4_CLEAR),
208 };
209 
210 static const struct regmap_access_table msm8998_bwmon_reg_read_table = {
211 	.no_ranges	= msm8998_bwmon_reg_noread_ranges,
212 	.n_no_ranges	= ARRAY_SIZE(msm8998_bwmon_reg_noread_ranges),
213 };
214 
215 static const struct regmap_range msm8998_bwmon_reg_volatile_ranges[] = {
216 	regmap_reg_range(BWMON_V4_IRQ_STATUS, BWMON_V4_IRQ_STATUS),
217 	regmap_reg_range(BWMON_V4_ZONE_MAX(0), BWMON_V4_ZONE_MAX(3)),
218 };
219 
220 static const struct regmap_access_table msm8998_bwmon_reg_volatile_table = {
221 	.yes_ranges	= msm8998_bwmon_reg_volatile_ranges,
222 	.n_yes_ranges	= ARRAY_SIZE(msm8998_bwmon_reg_volatile_ranges),
223 };
224 
225 /*
226  * Fill the cache for non-readable registers only as rest does not really
227  * matter and can be read from the device.
228  */
229 static const struct reg_default msm8998_bwmon_reg_defaults[] = {
230 	{ BWMON_V4_GLOBAL_IRQ_CLEAR, 0x0 },
231 	{ BWMON_V4_IRQ_CLEAR, 0x0 },
232 	{ BWMON_V4_CLEAR, 0x0 },
233 };
234 
235 static const struct regmap_config msm8998_bwmon_regmap_cfg = {
236 	.reg_bits		= 32,
237 	.reg_stride		= 4,
238 	.val_bits		= 32,
239 	/*
240 	 * No concurrent access expected - driver has one interrupt handler,
241 	 * regmap is not shared, no driver or user-space API.
242 	 */
243 	.disable_locking	= true,
244 	.rd_table		= &msm8998_bwmon_reg_read_table,
245 	.volatile_table		= &msm8998_bwmon_reg_volatile_table,
246 	.reg_defaults		= msm8998_bwmon_reg_defaults,
247 	.num_reg_defaults	= ARRAY_SIZE(msm8998_bwmon_reg_defaults),
248 	/*
249 	 * Cache is necessary for using regmap fields with non-readable
250 	 * registers.
251 	 */
252 	.cache_type		= REGCACHE_RBTREE,
253 };
254 
255 /* BWMON v5 */
256 static const struct reg_field sdm845_llcc_bwmon_reg_fields[] = {
257 	[F_GLOBAL_IRQ_CLEAR]	= {},
258 	[F_GLOBAL_IRQ_ENABLE]	= {},
259 	[F_IRQ_STATUS]		= REG_FIELD(BWMON_V5_IRQ_STATUS, 0, 3),
260 	[F_IRQ_CLEAR]		= REG_FIELD(BWMON_V5_IRQ_CLEAR, 0, 3),
261 	[F_IRQ_ENABLE]		= REG_FIELD(BWMON_V5_IRQ_ENABLE, 0, 3),
262 	/* F_ENABLE covers entire register to disable other features */
263 	[F_ENABLE]		= REG_FIELD(BWMON_V5_ENABLE, 0, 31),
264 	[F_CLEAR]		= REG_FIELD(BWMON_V5_CLEAR, 0, 1),
265 	[F_SAMPLE_WINDOW]	= REG_FIELD(BWMON_V5_SAMPLE_WINDOW, 0, 19),
266 	[F_THRESHOLD_HIGH]	= REG_FIELD(BWMON_V5_THRESHOLD_HIGH, 0, 11),
267 	[F_THRESHOLD_MED]	= REG_FIELD(BWMON_V5_THRESHOLD_MED, 0, 11),
268 	[F_THRESHOLD_LOW]	= REG_FIELD(BWMON_V5_THRESHOLD_LOW, 0, 11),
269 	[F_ZONE_ACTIONS_ZONE0]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 0, 7),
270 	[F_ZONE_ACTIONS_ZONE1]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 8, 15),
271 	[F_ZONE_ACTIONS_ZONE2]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 16, 23),
272 	[F_ZONE_ACTIONS_ZONE3]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 24, 31),
273 	[F_THRESHOLD_COUNT_ZONE0]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 0, 7),
274 	[F_THRESHOLD_COUNT_ZONE1]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 8, 15),
275 	[F_THRESHOLD_COUNT_ZONE2]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 16, 23),
276 	[F_THRESHOLD_COUNT_ZONE3]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 24, 31),
277 	[F_ZONE0_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(0), 0, 11),
278 	[F_ZONE1_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(1), 0, 11),
279 	[F_ZONE2_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(2), 0, 11),
280 	[F_ZONE3_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(3), 0, 11),
281 };
282 
283 static const struct regmap_range sdm845_llcc_bwmon_reg_noread_ranges[] = {
284 	regmap_reg_range(BWMON_V5_IRQ_CLEAR, BWMON_V5_IRQ_CLEAR),
285 	regmap_reg_range(BWMON_V5_CLEAR, BWMON_V5_CLEAR),
286 };
287 
288 static const struct regmap_access_table sdm845_llcc_bwmon_reg_read_table = {
289 	.no_ranges	= sdm845_llcc_bwmon_reg_noread_ranges,
290 	.n_no_ranges	= ARRAY_SIZE(sdm845_llcc_bwmon_reg_noread_ranges),
291 };
292 
293 static const struct regmap_range sdm845_llcc_bwmon_reg_volatile_ranges[] = {
294 	regmap_reg_range(BWMON_V5_IRQ_STATUS, BWMON_V5_IRQ_STATUS),
295 	regmap_reg_range(BWMON_V5_ZONE_MAX(0), BWMON_V5_ZONE_MAX(3)),
296 };
297 
298 static const struct regmap_access_table sdm845_llcc_bwmon_reg_volatile_table = {
299 	.yes_ranges	= sdm845_llcc_bwmon_reg_volatile_ranges,
300 	.n_yes_ranges	= ARRAY_SIZE(sdm845_llcc_bwmon_reg_volatile_ranges),
301 };
302 
303 /*
304  * Fill the cache for non-readable registers only as rest does not really
305  * matter and can be read from the device.
306  */
307 static const struct reg_default sdm845_llcc_bwmon_reg_defaults[] = {
308 	{ BWMON_V5_IRQ_CLEAR, 0x0 },
309 	{ BWMON_V5_CLEAR, 0x0 },
310 };
311 
312 static const struct regmap_config sdm845_llcc_bwmon_regmap_cfg = {
313 	.reg_bits		= 32,
314 	.reg_stride		= 4,
315 	.val_bits		= 32,
316 	/*
317 	 * No concurrent access expected - driver has one interrupt handler,
318 	 * regmap is not shared, no driver or user-space API.
319 	 */
320 	.disable_locking	= true,
321 	.rd_table		= &sdm845_llcc_bwmon_reg_read_table,
322 	.volatile_table		= &sdm845_llcc_bwmon_reg_volatile_table,
323 	.reg_defaults		= sdm845_llcc_bwmon_reg_defaults,
324 	.num_reg_defaults	= ARRAY_SIZE(sdm845_llcc_bwmon_reg_defaults),
325 	/*
326 	 * Cache is necessary for using regmap fields with non-readable
327 	 * registers.
328 	 */
329 	.cache_type		= REGCACHE_RBTREE,
330 };
331 
332 static void bwmon_clear_counters(struct icc_bwmon *bwmon, bool clear_all)
333 {
334 	unsigned int val = BWMON_CLEAR_CLEAR;
335 
336 	if (clear_all)
337 		val |= BWMON_CLEAR_CLEAR_ALL;
338 	/*
339 	 * Clear counters. The order and barriers are
340 	 * important. Quoting downstream Qualcomm msm-4.9 tree:
341 	 *
342 	 * The counter clear and IRQ clear bits are not in the same 4KB
343 	 * region. So, we need to make sure the counter clear is completed
344 	 * before we try to clear the IRQ or do any other counter operations.
345 	 */
346 	regmap_field_force_write(bwmon->regs[F_CLEAR], val);
347 	if (bwmon->data->quirks & BWMON_NEEDS_FORCE_CLEAR)
348 		regmap_field_force_write(bwmon->regs[F_CLEAR], 0);
349 }
350 
351 static void bwmon_clear_irq(struct icc_bwmon *bwmon)
352 {
353 	/*
354 	 * Clear zone and global interrupts. The order and barriers are
355 	 * important. Quoting downstream Qualcomm msm-4.9 tree:
356 	 *
357 	 * Synchronize the local interrupt clear in mon_irq_clear()
358 	 * with the global interrupt clear here. Otherwise, the CPU
359 	 * may reorder the two writes and clear the global interrupt
360 	 * before the local interrupt, causing the global interrupt
361 	 * to be retriggered by the local interrupt still being high.
362 	 *
363 	 * Similarly, because the global registers are in a different
364 	 * region than the local registers, we need to ensure any register
365 	 * writes to enable the monitor after this call are ordered with the
366 	 * clearing here so that local writes don't happen before the
367 	 * interrupt is cleared.
368 	 */
369 	regmap_field_force_write(bwmon->regs[F_IRQ_CLEAR], BWMON_IRQ_ENABLE_MASK);
370 	if (bwmon->data->quirks & BWMON_NEEDS_FORCE_CLEAR)
371 		regmap_field_force_write(bwmon->regs[F_IRQ_CLEAR], 0);
372 	if (bwmon->data->quirks & BWMON_HAS_GLOBAL_IRQ)
373 		regmap_field_force_write(bwmon->regs[F_GLOBAL_IRQ_CLEAR],
374 					 BWMON_V4_GLOBAL_IRQ_ENABLE_ENABLE);
375 }
376 
377 static void bwmon_disable(struct icc_bwmon *bwmon)
378 {
379 	/* Disable interrupts. Strict ordering, see bwmon_clear_irq(). */
380 	if (bwmon->data->quirks & BWMON_HAS_GLOBAL_IRQ)
381 		regmap_field_write(bwmon->regs[F_GLOBAL_IRQ_ENABLE], 0x0);
382 	regmap_field_write(bwmon->regs[F_IRQ_ENABLE], 0x0);
383 
384 	/*
385 	 * Disable bwmon. Must happen before bwmon_clear_irq() to avoid spurious
386 	 * IRQ.
387 	 */
388 	regmap_field_write(bwmon->regs[F_ENABLE], 0x0);
389 }
390 
391 static void bwmon_enable(struct icc_bwmon *bwmon, unsigned int irq_enable)
392 {
393 	/* Enable interrupts */
394 	if (bwmon->data->quirks & BWMON_HAS_GLOBAL_IRQ)
395 		regmap_field_write(bwmon->regs[F_GLOBAL_IRQ_ENABLE],
396 				   BWMON_V4_GLOBAL_IRQ_ENABLE_ENABLE);
397 	regmap_field_write(bwmon->regs[F_IRQ_ENABLE], irq_enable);
398 
399 	/* Enable bwmon */
400 	regmap_field_write(bwmon->regs[F_ENABLE], BWMON_ENABLE_ENABLE);
401 }
402 
403 static unsigned int bwmon_kbps_to_count(struct icc_bwmon *bwmon,
404 					unsigned int kbps)
405 {
406 	return kbps / bwmon->data->count_unit_kb;
407 }
408 
409 static void bwmon_set_threshold(struct icc_bwmon *bwmon,
410 				struct regmap_field *reg, unsigned int kbps)
411 {
412 	unsigned int thres;
413 
414 	thres = mult_frac(bwmon_kbps_to_count(bwmon, kbps),
415 			  bwmon->data->sample_ms, MSEC_PER_SEC);
416 	regmap_field_write(reg, thres);
417 }
418 
419 static void bwmon_start(struct icc_bwmon *bwmon)
420 {
421 	const struct icc_bwmon_data *data = bwmon->data;
422 	int window;
423 
424 	bwmon_clear_counters(bwmon, true);
425 
426 	window = mult_frac(bwmon->data->sample_ms, HW_TIMER_HZ, MSEC_PER_SEC);
427 	/* Maximum sampling window: 0xffffff for v4 and 0xfffff for v5 */
428 	regmap_field_write(bwmon->regs[F_SAMPLE_WINDOW], window);
429 
430 	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_HIGH],
431 			    data->default_highbw_kbps);
432 	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_MED],
433 			    data->default_medbw_kbps);
434 	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_LOW],
435 			    data->default_lowbw_kbps);
436 
437 	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE0],
438 			   BWMON_THRESHOLD_COUNT_ZONE0_DEFAULT);
439 	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE1],
440 			   data->zone1_thres_count);
441 	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE2],
442 			   BWMON_THRESHOLD_COUNT_ZONE2_DEFAULT);
443 	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE3],
444 			   data->zone3_thres_count);
445 
446 	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE0],
447 			   BWMON_ZONE_ACTIONS_ZONE0);
448 	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE1],
449 			   BWMON_ZONE_ACTIONS_ZONE1);
450 	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE2],
451 			   BWMON_ZONE_ACTIONS_ZONE2);
452 	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE3],
453 			   BWMON_ZONE_ACTIONS_ZONE3);
454 
455 	bwmon_clear_irq(bwmon);
456 	bwmon_enable(bwmon, BWMON_IRQ_ENABLE_MASK);
457 }
458 
459 static irqreturn_t bwmon_intr(int irq, void *dev_id)
460 {
461 	struct icc_bwmon *bwmon = dev_id;
462 	unsigned int status, max;
463 	int zone;
464 
465 	if (regmap_field_read(bwmon->regs[F_IRQ_STATUS], &status))
466 		return IRQ_NONE;
467 
468 	status &= BWMON_IRQ_ENABLE_MASK;
469 	if (!status) {
470 		/*
471 		 * Only zone 1 and zone 3 interrupts are enabled but zone 2
472 		 * threshold could be hit and trigger interrupt even if not
473 		 * enabled.
474 		 * Such spurious interrupt might come with valuable max count or
475 		 * not, so solution would be to always check all
476 		 * BWMON_ZONE_MAX() registers to find the highest value.
477 		 * Such case is currently ignored.
478 		 */
479 		return IRQ_NONE;
480 	}
481 
482 	bwmon_disable(bwmon);
483 
484 	zone = get_bitmask_order(status) - 1;
485 	/*
486 	 * Zone max bytes count register returns count units within sampling
487 	 * window.  Downstream kernel for BWMONv4 (called BWMON type 2 in
488 	 * downstream) always increments the max bytes count by one.
489 	 */
490 	if (regmap_field_read(bwmon->regs[F_ZONE0_MAX + zone], &max))
491 		return IRQ_NONE;
492 
493 	max += 1;
494 	max *= bwmon->data->count_unit_kb;
495 	bwmon->target_kbps = mult_frac(max, MSEC_PER_SEC, bwmon->data->sample_ms);
496 
497 	return IRQ_WAKE_THREAD;
498 }
499 
500 static irqreturn_t bwmon_intr_thread(int irq, void *dev_id)
501 {
502 	struct icc_bwmon *bwmon = dev_id;
503 	unsigned int irq_enable = 0;
504 	struct dev_pm_opp *opp, *target_opp;
505 	unsigned int bw_kbps, up_kbps, down_kbps;
506 
507 	bw_kbps = bwmon->target_kbps;
508 
509 	target_opp = dev_pm_opp_find_bw_ceil(bwmon->dev, &bw_kbps, 0);
510 	if (IS_ERR(target_opp) && PTR_ERR(target_opp) == -ERANGE)
511 		target_opp = dev_pm_opp_find_bw_floor(bwmon->dev, &bw_kbps, 0);
512 
513 	bwmon->target_kbps = bw_kbps;
514 
515 	bw_kbps--;
516 	opp = dev_pm_opp_find_bw_floor(bwmon->dev, &bw_kbps, 0);
517 	if (IS_ERR(opp) && PTR_ERR(opp) == -ERANGE)
518 		down_kbps = bwmon->target_kbps;
519 	else
520 		down_kbps = bw_kbps;
521 
522 	up_kbps = bwmon->target_kbps + 1;
523 
524 	if (bwmon->target_kbps >= bwmon->max_bw_kbps)
525 		irq_enable = BIT(1);
526 	else if (bwmon->target_kbps <= bwmon->min_bw_kbps)
527 		irq_enable = BIT(3);
528 	else
529 		irq_enable = BWMON_IRQ_ENABLE_MASK;
530 
531 	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_HIGH],
532 			    up_kbps);
533 	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_MED],
534 			    down_kbps);
535 	bwmon_clear_counters(bwmon, false);
536 	bwmon_clear_irq(bwmon);
537 	bwmon_enable(bwmon, irq_enable);
538 
539 	if (bwmon->target_kbps == bwmon->current_kbps)
540 		goto out;
541 
542 	dev_pm_opp_set_opp(bwmon->dev, target_opp);
543 	bwmon->current_kbps = bwmon->target_kbps;
544 
545 out:
546 	dev_pm_opp_put(target_opp);
547 	if (!IS_ERR(opp))
548 		dev_pm_opp_put(opp);
549 
550 	return IRQ_HANDLED;
551 }
552 
553 static int bwmon_init_regmap(struct platform_device *pdev,
554 			     struct icc_bwmon *bwmon)
555 {
556 	struct device *dev = &pdev->dev;
557 	void __iomem *base;
558 	struct regmap *map;
559 
560 	base = devm_platform_ioremap_resource(pdev, 0);
561 	if (IS_ERR(base))
562 		return dev_err_probe(dev, PTR_ERR(base),
563 				     "failed to map bwmon registers\n");
564 
565 	map = devm_regmap_init_mmio(dev, base, bwmon->data->regmap_cfg);
566 	if (IS_ERR(map))
567 		return dev_err_probe(dev, PTR_ERR(map),
568 				     "failed to initialize regmap\n");
569 
570 	BUILD_BUG_ON(ARRAY_SIZE(msm8998_bwmon_reg_fields) != F_NUM_FIELDS);
571 	BUILD_BUG_ON(ARRAY_SIZE(sdm845_llcc_bwmon_reg_fields) != F_NUM_FIELDS);
572 
573 	return devm_regmap_field_bulk_alloc(dev, map, bwmon->regs,
574 					   bwmon->data->regmap_fields,
575 					   F_NUM_FIELDS);
576 }
577 
578 static int bwmon_probe(struct platform_device *pdev)
579 {
580 	struct device *dev = &pdev->dev;
581 	struct dev_pm_opp *opp;
582 	struct icc_bwmon *bwmon;
583 	int ret;
584 
585 	bwmon = devm_kzalloc(dev, sizeof(*bwmon), GFP_KERNEL);
586 	if (!bwmon)
587 		return -ENOMEM;
588 
589 	bwmon->data = of_device_get_match_data(dev);
590 
591 	ret = bwmon_init_regmap(pdev, bwmon);
592 	if (ret)
593 		return ret;
594 
595 	bwmon->irq = platform_get_irq(pdev, 0);
596 	if (bwmon->irq < 0)
597 		return bwmon->irq;
598 
599 	ret = devm_pm_opp_of_add_table(dev);
600 	if (ret)
601 		return dev_err_probe(dev, ret, "failed to add OPP table\n");
602 
603 	bwmon->max_bw_kbps = UINT_MAX;
604 	opp = dev_pm_opp_find_bw_floor(dev, &bwmon->max_bw_kbps, 0);
605 	if (IS_ERR(opp))
606 		return dev_err_probe(dev, ret, "failed to find max peak bandwidth\n");
607 
608 	bwmon->min_bw_kbps = 0;
609 	opp = dev_pm_opp_find_bw_ceil(dev, &bwmon->min_bw_kbps, 0);
610 	if (IS_ERR(opp))
611 		return dev_err_probe(dev, ret, "failed to find min peak bandwidth\n");
612 
613 	bwmon->dev = dev;
614 
615 	bwmon_disable(bwmon);
616 	ret = devm_request_threaded_irq(dev, bwmon->irq, bwmon_intr,
617 					bwmon_intr_thread,
618 					IRQF_ONESHOT, dev_name(dev), bwmon);
619 	if (ret)
620 		return dev_err_probe(dev, ret, "failed to request IRQ\n");
621 
622 	platform_set_drvdata(pdev, bwmon);
623 	bwmon_start(bwmon);
624 
625 	return 0;
626 }
627 
628 static int bwmon_remove(struct platform_device *pdev)
629 {
630 	struct icc_bwmon *bwmon = platform_get_drvdata(pdev);
631 
632 	bwmon_disable(bwmon);
633 
634 	return 0;
635 }
636 
637 static const struct icc_bwmon_data msm8998_bwmon_data = {
638 	.sample_ms = 4,
639 	.count_unit_kb = 64,
640 	.default_highbw_kbps = 4800 * 1024, /* 4.8 GBps */
641 	.default_medbw_kbps = 512 * 1024, /* 512 MBps */
642 	.default_lowbw_kbps = 0,
643 	.zone1_thres_count = 16,
644 	.zone3_thres_count = 1,
645 	.quirks = BWMON_HAS_GLOBAL_IRQ,
646 	.regmap_fields = msm8998_bwmon_reg_fields,
647 	.regmap_cfg = &msm8998_bwmon_regmap_cfg,
648 };
649 
650 static const struct icc_bwmon_data sdm845_llcc_bwmon_data = {
651 	.sample_ms = 4,
652 	.count_unit_kb = 1024,
653 	.default_highbw_kbps = 800 * 1024, /* 800 MBps */
654 	.default_medbw_kbps = 256 * 1024, /* 256 MBps */
655 	.default_lowbw_kbps = 0,
656 	.zone1_thres_count = 16,
657 	.zone3_thres_count = 1,
658 	.regmap_fields = sdm845_llcc_bwmon_reg_fields,
659 	.regmap_cfg = &sdm845_llcc_bwmon_regmap_cfg,
660 };
661 
662 static const struct icc_bwmon_data sc7280_llcc_bwmon_data = {
663 	.sample_ms = 4,
664 	.count_unit_kb = 64,
665 	.default_highbw_kbps = 800 * 1024, /* 800 MBps */
666 	.default_medbw_kbps = 256 * 1024, /* 256 MBps */
667 	.default_lowbw_kbps = 0,
668 	.zone1_thres_count = 16,
669 	.zone3_thres_count = 1,
670 	.quirks = BWMON_NEEDS_FORCE_CLEAR,
671 	.regmap_fields = sdm845_llcc_bwmon_reg_fields,
672 	.regmap_cfg = &sdm845_llcc_bwmon_regmap_cfg,
673 };
674 
675 static const struct of_device_id bwmon_of_match[] = {
676 	{
677 		.compatible = "qcom,msm8998-bwmon",
678 		.data = &msm8998_bwmon_data
679 	}, {
680 		.compatible = "qcom,sdm845-llcc-bwmon",
681 		.data = &sdm845_llcc_bwmon_data
682 	}, {
683 		.compatible = "qcom,sc7280-llcc-bwmon",
684 		.data = &sc7280_llcc_bwmon_data
685 	},
686 	{}
687 };
688 MODULE_DEVICE_TABLE(of, bwmon_of_match);
689 
690 static struct platform_driver bwmon_driver = {
691 	.probe = bwmon_probe,
692 	.remove = bwmon_remove,
693 	.driver = {
694 		.name = "qcom-bwmon",
695 		.of_match_table = bwmon_of_match,
696 	},
697 };
698 module_platform_driver(bwmon_driver);
699 
700 MODULE_AUTHOR("Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>");
701 MODULE_DESCRIPTION("QCOM BWMON driver");
702 MODULE_LICENSE("GPL");
703