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.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		0x108
38 #define BWMON_V4_GLOBAL_IRQ_ENABLE		0x10c
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 /*
46  * Starting with SDM845, the BWMON4 register space has changed a bit:
47  * the global registers were jammed into the beginning of the monitor region.
48  * To keep the proper offsets, one would have to map <GLOBAL_BASE 0x200> and
49  * <GLOBAL_BASE+0x100 0x300>, which is straight up wrong.
50  * To facilitate for that, while allowing the older, arguably more proper
51  * implementations to work, offset the global registers by -0x100 to avoid
52  * having to map half of the global registers twice.
53  */
54 #define BWMON_V4_845_OFFSET			0x100
55 #define BWMON_V4_GLOBAL_IRQ_CLEAR_845		(BWMON_V4_GLOBAL_IRQ_CLEAR - BWMON_V4_845_OFFSET)
56 #define BWMON_V4_GLOBAL_IRQ_ENABLE_845		(BWMON_V4_GLOBAL_IRQ_ENABLE - BWMON_V4_845_OFFSET)
57 
58 #define BWMON_V4_IRQ_STATUS			0x100
59 #define BWMON_V4_IRQ_CLEAR			0x108
60 
61 #define BWMON_V4_IRQ_ENABLE			0x10c
62 #define BWMON_IRQ_ENABLE_MASK			(BIT(1) | BIT(3))
63 #define BWMON_V5_IRQ_STATUS			0x000
64 #define BWMON_V5_IRQ_CLEAR			0x008
65 #define BWMON_V5_IRQ_ENABLE			0x00c
66 
67 #define BWMON_V4_ENABLE				0x2a0
68 #define BWMON_V5_ENABLE				0x010
69 #define BWMON_ENABLE_ENABLE			BIT(0)
70 
71 #define BWMON_V4_CLEAR				0x2a4
72 #define BWMON_V5_CLEAR				0x014
73 #define BWMON_CLEAR_CLEAR			BIT(0)
74 #define BWMON_CLEAR_CLEAR_ALL			BIT(1)
75 
76 #define BWMON_V4_SAMPLE_WINDOW			0x2a8
77 #define BWMON_V5_SAMPLE_WINDOW			0x020
78 
79 #define BWMON_V4_THRESHOLD_HIGH			0x2ac
80 #define BWMON_V4_THRESHOLD_MED			0x2b0
81 #define BWMON_V4_THRESHOLD_LOW			0x2b4
82 #define BWMON_V5_THRESHOLD_HIGH			0x024
83 #define BWMON_V5_THRESHOLD_MED			0x028
84 #define BWMON_V5_THRESHOLD_LOW			0x02c
85 
86 #define BWMON_V4_ZONE_ACTIONS			0x2b8
87 #define BWMON_V5_ZONE_ACTIONS			0x030
88 /*
89  * Actions to perform on some zone 'z' when current zone hits the threshold:
90  * Increment counter of zone 'z'
91  */
92 #define BWMON_ZONE_ACTIONS_INCREMENT(z)		(0x2 << ((z) * 2))
93 /* Clear counter of zone 'z' */
94 #define BWMON_ZONE_ACTIONS_CLEAR(z)		(0x1 << ((z) * 2))
95 
96 /* Zone 0 threshold hit: Clear zone count */
97 #define BWMON_ZONE_ACTIONS_ZONE0		(BWMON_ZONE_ACTIONS_CLEAR(0))
98 
99 /* Zone 1 threshold hit: Increment zone count & clear lower zones */
100 #define BWMON_ZONE_ACTIONS_ZONE1		(BWMON_ZONE_ACTIONS_INCREMENT(1) | \
101 						 BWMON_ZONE_ACTIONS_CLEAR(0))
102 
103 /* Zone 2 threshold hit: Increment zone count & clear lower zones */
104 #define BWMON_ZONE_ACTIONS_ZONE2		(BWMON_ZONE_ACTIONS_INCREMENT(2) | \
105 						 BWMON_ZONE_ACTIONS_CLEAR(1) | \
106 						 BWMON_ZONE_ACTIONS_CLEAR(0))
107 
108 /* Zone 3 threshold hit: Increment zone count & clear lower zones */
109 #define BWMON_ZONE_ACTIONS_ZONE3		(BWMON_ZONE_ACTIONS_INCREMENT(3) | \
110 						 BWMON_ZONE_ACTIONS_CLEAR(2) | \
111 						 BWMON_ZONE_ACTIONS_CLEAR(1) | \
112 						 BWMON_ZONE_ACTIONS_CLEAR(0))
113 
114 /*
115  * There is no clear documentation/explanation of BWMON_V4_THRESHOLD_COUNT
116  * register. Based on observations, this is number of times one threshold has to
117  * be reached, to trigger interrupt in given zone.
118  *
119  * 0xff are maximum values meant to ignore the zones 0 and 2.
120  */
121 #define BWMON_V4_THRESHOLD_COUNT		0x2bc
122 #define BWMON_V5_THRESHOLD_COUNT		0x034
123 #define BWMON_THRESHOLD_COUNT_ZONE0_DEFAULT	0xff
124 #define BWMON_THRESHOLD_COUNT_ZONE2_DEFAULT	0xff
125 
126 #define BWMON_V4_ZONE_MAX(zone)			(0x2e0 + 4 * (zone))
127 #define BWMON_V5_ZONE_MAX(zone)			(0x044 + 4 * (zone))
128 
129 /* Quirks for specific BWMON types */
130 #define BWMON_HAS_GLOBAL_IRQ			BIT(0)
131 #define BWMON_NEEDS_FORCE_CLEAR			BIT(1)
132 
133 enum bwmon_fields {
134 	/* Global region fields, keep them at the top */
135 	F_GLOBAL_IRQ_CLEAR,
136 	F_GLOBAL_IRQ_ENABLE,
137 	F_NUM_GLOBAL_FIELDS,
138 
139 	/* Monitor region fields */
140 	F_IRQ_STATUS = F_NUM_GLOBAL_FIELDS,
141 	F_IRQ_CLEAR,
142 	F_IRQ_ENABLE,
143 	F_ENABLE,
144 	F_CLEAR,
145 	F_SAMPLE_WINDOW,
146 	F_THRESHOLD_HIGH,
147 	F_THRESHOLD_MED,
148 	F_THRESHOLD_LOW,
149 	F_ZONE_ACTIONS_ZONE0,
150 	F_ZONE_ACTIONS_ZONE1,
151 	F_ZONE_ACTIONS_ZONE2,
152 	F_ZONE_ACTIONS_ZONE3,
153 	F_THRESHOLD_COUNT_ZONE0,
154 	F_THRESHOLD_COUNT_ZONE1,
155 	F_THRESHOLD_COUNT_ZONE2,
156 	F_THRESHOLD_COUNT_ZONE3,
157 	F_ZONE0_MAX,
158 	F_ZONE1_MAX,
159 	F_ZONE2_MAX,
160 	F_ZONE3_MAX,
161 
162 	F_NUM_FIELDS
163 };
164 
165 struct icc_bwmon_data {
166 	unsigned int sample_ms;
167 	unsigned int count_unit_kb; /* kbytes */
168 	u8 zone1_thres_count;
169 	u8 zone3_thres_count;
170 	unsigned int quirks;
171 
172 	const struct regmap_config *regmap_cfg;
173 	const struct reg_field *regmap_fields;
174 
175 	const struct regmap_config *global_regmap_cfg;
176 	const struct reg_field *global_regmap_fields;
177 };
178 
179 struct icc_bwmon {
180 	struct device *dev;
181 	const struct icc_bwmon_data *data;
182 	int irq;
183 
184 	struct regmap_field *regs[F_NUM_FIELDS];
185 	struct regmap_field *global_regs[F_NUM_GLOBAL_FIELDS];
186 
187 	unsigned int max_bw_kbps;
188 	unsigned int min_bw_kbps;
189 	unsigned int target_kbps;
190 	unsigned int current_kbps;
191 };
192 
193 /* BWMON v4 */
194 static const struct reg_field msm8998_bwmon_reg_fields[] = {
195 	[F_GLOBAL_IRQ_CLEAR]	= {},
196 	[F_GLOBAL_IRQ_ENABLE]	= {},
197 	[F_IRQ_STATUS]		= REG_FIELD(BWMON_V4_IRQ_STATUS, 4, 7),
198 	[F_IRQ_CLEAR]		= REG_FIELD(BWMON_V4_IRQ_CLEAR, 4, 7),
199 	[F_IRQ_ENABLE]		= REG_FIELD(BWMON_V4_IRQ_ENABLE, 4, 7),
200 	/* F_ENABLE covers entire register to disable other features */
201 	[F_ENABLE]		= REG_FIELD(BWMON_V4_ENABLE, 0, 31),
202 	[F_CLEAR]		= REG_FIELD(BWMON_V4_CLEAR, 0, 1),
203 	[F_SAMPLE_WINDOW]	= REG_FIELD(BWMON_V4_SAMPLE_WINDOW, 0, 23),
204 	[F_THRESHOLD_HIGH]	= REG_FIELD(BWMON_V4_THRESHOLD_HIGH, 0, 11),
205 	[F_THRESHOLD_MED]	= REG_FIELD(BWMON_V4_THRESHOLD_MED, 0, 11),
206 	[F_THRESHOLD_LOW]	= REG_FIELD(BWMON_V4_THRESHOLD_LOW, 0, 11),
207 	[F_ZONE_ACTIONS_ZONE0]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 0, 7),
208 	[F_ZONE_ACTIONS_ZONE1]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 8, 15),
209 	[F_ZONE_ACTIONS_ZONE2]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 16, 23),
210 	[F_ZONE_ACTIONS_ZONE3]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 24, 31),
211 	[F_THRESHOLD_COUNT_ZONE0]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 0, 7),
212 	[F_THRESHOLD_COUNT_ZONE1]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 8, 15),
213 	[F_THRESHOLD_COUNT_ZONE2]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 16, 23),
214 	[F_THRESHOLD_COUNT_ZONE3]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 24, 31),
215 	[F_ZONE0_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(0), 0, 11),
216 	[F_ZONE1_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(1), 0, 11),
217 	[F_ZONE2_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(2), 0, 11),
218 	[F_ZONE3_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(3), 0, 11),
219 };
220 
221 static const struct regmap_range msm8998_bwmon_reg_noread_ranges[] = {
222 	regmap_reg_range(BWMON_V4_IRQ_CLEAR, BWMON_V4_IRQ_CLEAR),
223 	regmap_reg_range(BWMON_V4_CLEAR, BWMON_V4_CLEAR),
224 };
225 
226 static const struct regmap_access_table msm8998_bwmon_reg_read_table = {
227 	.no_ranges	= msm8998_bwmon_reg_noread_ranges,
228 	.n_no_ranges	= ARRAY_SIZE(msm8998_bwmon_reg_noread_ranges),
229 };
230 
231 static const struct regmap_range msm8998_bwmon_reg_volatile_ranges[] = {
232 	regmap_reg_range(BWMON_V4_IRQ_STATUS, BWMON_V4_IRQ_STATUS),
233 	regmap_reg_range(BWMON_V4_ZONE_MAX(0), BWMON_V4_ZONE_MAX(3)),
234 };
235 
236 static const struct regmap_access_table msm8998_bwmon_reg_volatile_table = {
237 	.yes_ranges	= msm8998_bwmon_reg_volatile_ranges,
238 	.n_yes_ranges	= ARRAY_SIZE(msm8998_bwmon_reg_volatile_ranges),
239 };
240 
241 static const struct reg_field msm8998_bwmon_global_reg_fields[] = {
242 	[F_GLOBAL_IRQ_CLEAR]	= REG_FIELD(BWMON_V4_GLOBAL_IRQ_CLEAR, 0, 0),
243 	[F_GLOBAL_IRQ_ENABLE]	= REG_FIELD(BWMON_V4_GLOBAL_IRQ_ENABLE, 0, 0),
244 };
245 
246 static const struct regmap_range msm8998_bwmon_global_reg_noread_ranges[] = {
247 	regmap_reg_range(BWMON_V4_GLOBAL_IRQ_CLEAR, BWMON_V4_GLOBAL_IRQ_CLEAR),
248 };
249 
250 static const struct regmap_access_table msm8998_bwmon_global_reg_read_table = {
251 	.no_ranges	= msm8998_bwmon_global_reg_noread_ranges,
252 	.n_no_ranges	= ARRAY_SIZE(msm8998_bwmon_global_reg_noread_ranges),
253 };
254 
255 /*
256  * Fill the cache for non-readable registers only as rest does not really
257  * matter and can be read from the device.
258  */
259 static const struct reg_default msm8998_bwmon_reg_defaults[] = {
260 	{ BWMON_V4_IRQ_CLEAR, 0x0 },
261 	{ BWMON_V4_CLEAR, 0x0 },
262 };
263 
264 static const struct reg_default msm8998_bwmon_global_reg_defaults[] = {
265 	{ BWMON_V4_GLOBAL_IRQ_CLEAR, 0x0 },
266 };
267 
268 static const struct regmap_config msm8998_bwmon_regmap_cfg = {
269 	.reg_bits		= 32,
270 	.reg_stride		= 4,
271 	.val_bits		= 32,
272 	/*
273 	 * No concurrent access expected - driver has one interrupt handler,
274 	 * regmap is not shared, no driver or user-space API.
275 	 */
276 	.disable_locking	= true,
277 	.rd_table		= &msm8998_bwmon_reg_read_table,
278 	.volatile_table		= &msm8998_bwmon_reg_volatile_table,
279 	.reg_defaults		= msm8998_bwmon_reg_defaults,
280 	.num_reg_defaults	= ARRAY_SIZE(msm8998_bwmon_reg_defaults),
281 	/*
282 	 * Cache is necessary for using regmap fields with non-readable
283 	 * registers.
284 	 */
285 	.cache_type		= REGCACHE_RBTREE,
286 };
287 
288 static const struct regmap_config msm8998_bwmon_global_regmap_cfg = {
289 	.reg_bits		= 32,
290 	.reg_stride		= 4,
291 	.val_bits		= 32,
292 	/*
293 	 * No concurrent access expected - driver has one interrupt handler,
294 	 * regmap is not shared, no driver or user-space API.
295 	 */
296 	.disable_locking	= true,
297 	.rd_table		= &msm8998_bwmon_global_reg_read_table,
298 	.reg_defaults		= msm8998_bwmon_global_reg_defaults,
299 	.num_reg_defaults	= ARRAY_SIZE(msm8998_bwmon_global_reg_defaults),
300 	/*
301 	 * Cache is necessary for using regmap fields with non-readable
302 	 * registers.
303 	 */
304 	.cache_type		= REGCACHE_RBTREE,
305 };
306 
307 static const struct reg_field sdm845_cpu_bwmon_reg_fields[] = {
308 	[F_GLOBAL_IRQ_CLEAR]	= REG_FIELD(BWMON_V4_GLOBAL_IRQ_CLEAR_845, 0, 0),
309 	[F_GLOBAL_IRQ_ENABLE]	= REG_FIELD(BWMON_V4_GLOBAL_IRQ_ENABLE_845, 0, 0),
310 	[F_IRQ_STATUS]		= REG_FIELD(BWMON_V4_IRQ_STATUS, 4, 7),
311 	[F_IRQ_CLEAR]		= REG_FIELD(BWMON_V4_IRQ_CLEAR, 4, 7),
312 	[F_IRQ_ENABLE]		= REG_FIELD(BWMON_V4_IRQ_ENABLE, 4, 7),
313 	/* F_ENABLE covers entire register to disable other features */
314 	[F_ENABLE]		= REG_FIELD(BWMON_V4_ENABLE, 0, 31),
315 	[F_CLEAR]		= REG_FIELD(BWMON_V4_CLEAR, 0, 1),
316 	[F_SAMPLE_WINDOW]	= REG_FIELD(BWMON_V4_SAMPLE_WINDOW, 0, 23),
317 	[F_THRESHOLD_HIGH]	= REG_FIELD(BWMON_V4_THRESHOLD_HIGH, 0, 11),
318 	[F_THRESHOLD_MED]	= REG_FIELD(BWMON_V4_THRESHOLD_MED, 0, 11),
319 	[F_THRESHOLD_LOW]	= REG_FIELD(BWMON_V4_THRESHOLD_LOW, 0, 11),
320 	[F_ZONE_ACTIONS_ZONE0]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 0, 7),
321 	[F_ZONE_ACTIONS_ZONE1]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 8, 15),
322 	[F_ZONE_ACTIONS_ZONE2]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 16, 23),
323 	[F_ZONE_ACTIONS_ZONE3]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 24, 31),
324 	[F_THRESHOLD_COUNT_ZONE0]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 0, 7),
325 	[F_THRESHOLD_COUNT_ZONE1]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 8, 15),
326 	[F_THRESHOLD_COUNT_ZONE2]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 16, 23),
327 	[F_THRESHOLD_COUNT_ZONE3]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 24, 31),
328 	[F_ZONE0_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(0), 0, 11),
329 	[F_ZONE1_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(1), 0, 11),
330 	[F_ZONE2_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(2), 0, 11),
331 	[F_ZONE3_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(3), 0, 11),
332 };
333 
334 static const struct regmap_range sdm845_cpu_bwmon_reg_noread_ranges[] = {
335 	regmap_reg_range(BWMON_V4_GLOBAL_IRQ_CLEAR_845, BWMON_V4_GLOBAL_IRQ_CLEAR_845),
336 	regmap_reg_range(BWMON_V4_IRQ_CLEAR, BWMON_V4_IRQ_CLEAR),
337 	regmap_reg_range(BWMON_V4_CLEAR, BWMON_V4_CLEAR),
338 };
339 
340 static const struct regmap_access_table sdm845_cpu_bwmon_reg_read_table = {
341 	.no_ranges	= sdm845_cpu_bwmon_reg_noread_ranges,
342 	.n_no_ranges	= ARRAY_SIZE(sdm845_cpu_bwmon_reg_noread_ranges),
343 };
344 
345 /*
346  * Fill the cache for non-readable registers only as rest does not really
347  * matter and can be read from the device.
348  */
349 static const struct reg_default sdm845_cpu_bwmon_reg_defaults[] = {
350 	{ BWMON_V4_GLOBAL_IRQ_CLEAR_845, 0x0 },
351 	{ BWMON_V4_IRQ_CLEAR, 0x0 },
352 	{ BWMON_V4_CLEAR, 0x0 },
353 };
354 
355 static const struct regmap_config sdm845_cpu_bwmon_regmap_cfg = {
356 	.reg_bits		= 32,
357 	.reg_stride		= 4,
358 	.val_bits		= 32,
359 	/*
360 	 * No concurrent access expected - driver has one interrupt handler,
361 	 * regmap is not shared, no driver or user-space API.
362 	 */
363 	.disable_locking	= true,
364 	.rd_table		= &sdm845_cpu_bwmon_reg_read_table,
365 	.volatile_table		= &msm8998_bwmon_reg_volatile_table,
366 	.reg_defaults		= sdm845_cpu_bwmon_reg_defaults,
367 	.num_reg_defaults	= ARRAY_SIZE(sdm845_cpu_bwmon_reg_defaults),
368 	/*
369 	 * Cache is necessary for using regmap fields with non-readable
370 	 * registers.
371 	 */
372 	.cache_type		= REGCACHE_RBTREE,
373 };
374 
375 /* BWMON v5 */
376 static const struct reg_field sdm845_llcc_bwmon_reg_fields[] = {
377 	[F_GLOBAL_IRQ_CLEAR]	= {},
378 	[F_GLOBAL_IRQ_ENABLE]	= {},
379 	[F_IRQ_STATUS]		= REG_FIELD(BWMON_V5_IRQ_STATUS, 0, 3),
380 	[F_IRQ_CLEAR]		= REG_FIELD(BWMON_V5_IRQ_CLEAR, 0, 3),
381 	[F_IRQ_ENABLE]		= REG_FIELD(BWMON_V5_IRQ_ENABLE, 0, 3),
382 	/* F_ENABLE covers entire register to disable other features */
383 	[F_ENABLE]		= REG_FIELD(BWMON_V5_ENABLE, 0, 31),
384 	[F_CLEAR]		= REG_FIELD(BWMON_V5_CLEAR, 0, 1),
385 	[F_SAMPLE_WINDOW]	= REG_FIELD(BWMON_V5_SAMPLE_WINDOW, 0, 19),
386 	[F_THRESHOLD_HIGH]	= REG_FIELD(BWMON_V5_THRESHOLD_HIGH, 0, 11),
387 	[F_THRESHOLD_MED]	= REG_FIELD(BWMON_V5_THRESHOLD_MED, 0, 11),
388 	[F_THRESHOLD_LOW]	= REG_FIELD(BWMON_V5_THRESHOLD_LOW, 0, 11),
389 	[F_ZONE_ACTIONS_ZONE0]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 0, 7),
390 	[F_ZONE_ACTIONS_ZONE1]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 8, 15),
391 	[F_ZONE_ACTIONS_ZONE2]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 16, 23),
392 	[F_ZONE_ACTIONS_ZONE3]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 24, 31),
393 	[F_THRESHOLD_COUNT_ZONE0]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 0, 7),
394 	[F_THRESHOLD_COUNT_ZONE1]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 8, 15),
395 	[F_THRESHOLD_COUNT_ZONE2]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 16, 23),
396 	[F_THRESHOLD_COUNT_ZONE3]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 24, 31),
397 	[F_ZONE0_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(0), 0, 11),
398 	[F_ZONE1_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(1), 0, 11),
399 	[F_ZONE2_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(2), 0, 11),
400 	[F_ZONE3_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(3), 0, 11),
401 };
402 
403 static const struct regmap_range sdm845_llcc_bwmon_reg_noread_ranges[] = {
404 	regmap_reg_range(BWMON_V5_IRQ_CLEAR, BWMON_V5_IRQ_CLEAR),
405 	regmap_reg_range(BWMON_V5_CLEAR, BWMON_V5_CLEAR),
406 };
407 
408 static const struct regmap_access_table sdm845_llcc_bwmon_reg_read_table = {
409 	.no_ranges	= sdm845_llcc_bwmon_reg_noread_ranges,
410 	.n_no_ranges	= ARRAY_SIZE(sdm845_llcc_bwmon_reg_noread_ranges),
411 };
412 
413 static const struct regmap_range sdm845_llcc_bwmon_reg_volatile_ranges[] = {
414 	regmap_reg_range(BWMON_V5_IRQ_STATUS, BWMON_V5_IRQ_STATUS),
415 	regmap_reg_range(BWMON_V5_ZONE_MAX(0), BWMON_V5_ZONE_MAX(3)),
416 };
417 
418 static const struct regmap_access_table sdm845_llcc_bwmon_reg_volatile_table = {
419 	.yes_ranges	= sdm845_llcc_bwmon_reg_volatile_ranges,
420 	.n_yes_ranges	= ARRAY_SIZE(sdm845_llcc_bwmon_reg_volatile_ranges),
421 };
422 
423 /*
424  * Fill the cache for non-readable registers only as rest does not really
425  * matter and can be read from the device.
426  */
427 static const struct reg_default sdm845_llcc_bwmon_reg_defaults[] = {
428 	{ BWMON_V5_IRQ_CLEAR, 0x0 },
429 	{ BWMON_V5_CLEAR, 0x0 },
430 };
431 
432 static const struct regmap_config sdm845_llcc_bwmon_regmap_cfg = {
433 	.reg_bits		= 32,
434 	.reg_stride		= 4,
435 	.val_bits		= 32,
436 	/*
437 	 * No concurrent access expected - driver has one interrupt handler,
438 	 * regmap is not shared, no driver or user-space API.
439 	 */
440 	.disable_locking	= true,
441 	.rd_table		= &sdm845_llcc_bwmon_reg_read_table,
442 	.volatile_table		= &sdm845_llcc_bwmon_reg_volatile_table,
443 	.reg_defaults		= sdm845_llcc_bwmon_reg_defaults,
444 	.num_reg_defaults	= ARRAY_SIZE(sdm845_llcc_bwmon_reg_defaults),
445 	/*
446 	 * Cache is necessary for using regmap fields with non-readable
447 	 * registers.
448 	 */
449 	.cache_type		= REGCACHE_RBTREE,
450 };
451 
bwmon_clear_counters(struct icc_bwmon * bwmon,bool clear_all)452 static void bwmon_clear_counters(struct icc_bwmon *bwmon, bool clear_all)
453 {
454 	unsigned int val = BWMON_CLEAR_CLEAR;
455 
456 	if (clear_all)
457 		val |= BWMON_CLEAR_CLEAR_ALL;
458 	/*
459 	 * Clear counters. The order and barriers are
460 	 * important. Quoting downstream Qualcomm msm-4.9 tree:
461 	 *
462 	 * The counter clear and IRQ clear bits are not in the same 4KB
463 	 * region. So, we need to make sure the counter clear is completed
464 	 * before we try to clear the IRQ or do any other counter operations.
465 	 */
466 	regmap_field_force_write(bwmon->regs[F_CLEAR], val);
467 	if (bwmon->data->quirks & BWMON_NEEDS_FORCE_CLEAR)
468 		regmap_field_force_write(bwmon->regs[F_CLEAR], 0);
469 }
470 
bwmon_clear_irq(struct icc_bwmon * bwmon)471 static void bwmon_clear_irq(struct icc_bwmon *bwmon)
472 {
473 	struct regmap_field *global_irq_clr;
474 
475 	if (bwmon->data->global_regmap_fields)
476 		global_irq_clr = bwmon->global_regs[F_GLOBAL_IRQ_CLEAR];
477 	else
478 		global_irq_clr = bwmon->regs[F_GLOBAL_IRQ_CLEAR];
479 
480 	/*
481 	 * Clear zone and global interrupts. The order and barriers are
482 	 * important. Quoting downstream Qualcomm msm-4.9 tree:
483 	 *
484 	 * Synchronize the local interrupt clear in mon_irq_clear()
485 	 * with the global interrupt clear here. Otherwise, the CPU
486 	 * may reorder the two writes and clear the global interrupt
487 	 * before the local interrupt, causing the global interrupt
488 	 * to be retriggered by the local interrupt still being high.
489 	 *
490 	 * Similarly, because the global registers are in a different
491 	 * region than the local registers, we need to ensure any register
492 	 * writes to enable the monitor after this call are ordered with the
493 	 * clearing here so that local writes don't happen before the
494 	 * interrupt is cleared.
495 	 */
496 	regmap_field_force_write(bwmon->regs[F_IRQ_CLEAR], BWMON_IRQ_ENABLE_MASK);
497 	if (bwmon->data->quirks & BWMON_NEEDS_FORCE_CLEAR)
498 		regmap_field_force_write(bwmon->regs[F_IRQ_CLEAR], 0);
499 	if (bwmon->data->quirks & BWMON_HAS_GLOBAL_IRQ)
500 		regmap_field_force_write(global_irq_clr,
501 					 BWMON_V4_GLOBAL_IRQ_ENABLE_ENABLE);
502 }
503 
bwmon_disable(struct icc_bwmon * bwmon)504 static void bwmon_disable(struct icc_bwmon *bwmon)
505 {
506 	struct regmap_field *global_irq_en;
507 
508 	if (bwmon->data->global_regmap_fields)
509 		global_irq_en = bwmon->global_regs[F_GLOBAL_IRQ_ENABLE];
510 	else
511 		global_irq_en = bwmon->regs[F_GLOBAL_IRQ_ENABLE];
512 
513 	/* Disable interrupts. Strict ordering, see bwmon_clear_irq(). */
514 	if (bwmon->data->quirks & BWMON_HAS_GLOBAL_IRQ)
515 		regmap_field_write(global_irq_en, 0x0);
516 	regmap_field_write(bwmon->regs[F_IRQ_ENABLE], 0x0);
517 
518 	/*
519 	 * Disable bwmon. Must happen before bwmon_clear_irq() to avoid spurious
520 	 * IRQ.
521 	 */
522 	regmap_field_write(bwmon->regs[F_ENABLE], 0x0);
523 }
524 
bwmon_enable(struct icc_bwmon * bwmon,unsigned int irq_enable)525 static void bwmon_enable(struct icc_bwmon *bwmon, unsigned int irq_enable)
526 {
527 	struct regmap_field *global_irq_en;
528 
529 	if (bwmon->data->global_regmap_fields)
530 		global_irq_en = bwmon->global_regs[F_GLOBAL_IRQ_ENABLE];
531 	else
532 		global_irq_en = bwmon->regs[F_GLOBAL_IRQ_ENABLE];
533 
534 	/* Enable interrupts */
535 	if (bwmon->data->quirks & BWMON_HAS_GLOBAL_IRQ)
536 		regmap_field_write(global_irq_en,
537 				   BWMON_V4_GLOBAL_IRQ_ENABLE_ENABLE);
538 
539 	regmap_field_write(bwmon->regs[F_IRQ_ENABLE], irq_enable);
540 
541 	/* Enable bwmon */
542 	regmap_field_write(bwmon->regs[F_ENABLE], BWMON_ENABLE_ENABLE);
543 }
544 
bwmon_kbps_to_count(struct icc_bwmon * bwmon,unsigned int kbps)545 static unsigned int bwmon_kbps_to_count(struct icc_bwmon *bwmon,
546 					unsigned int kbps)
547 {
548 	return kbps / bwmon->data->count_unit_kb;
549 }
550 
bwmon_set_threshold(struct icc_bwmon * bwmon,struct regmap_field * reg,unsigned int kbps)551 static void bwmon_set_threshold(struct icc_bwmon *bwmon,
552 				struct regmap_field *reg, unsigned int kbps)
553 {
554 	unsigned int thres;
555 
556 	thres = mult_frac(bwmon_kbps_to_count(bwmon, kbps),
557 			  bwmon->data->sample_ms, MSEC_PER_SEC);
558 	regmap_field_write(reg, thres);
559 }
560 
bwmon_start(struct icc_bwmon * bwmon)561 static void bwmon_start(struct icc_bwmon *bwmon)
562 {
563 	const struct icc_bwmon_data *data = bwmon->data;
564 	u32 bw_low = 0;
565 	int window;
566 
567 	/* No need to check for errors, as this must have succeeded before. */
568 	dev_pm_opp_find_bw_ceil(bwmon->dev, &bw_low, 0);
569 
570 	bwmon_clear_counters(bwmon, true);
571 
572 	window = mult_frac(bwmon->data->sample_ms, HW_TIMER_HZ, MSEC_PER_SEC);
573 	/* Maximum sampling window: 0xffffff for v4 and 0xfffff for v5 */
574 	regmap_field_write(bwmon->regs[F_SAMPLE_WINDOW], window);
575 
576 	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_HIGH], bw_low);
577 	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_MED], bw_low);
578 	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_LOW], 0);
579 
580 	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE0],
581 			   BWMON_THRESHOLD_COUNT_ZONE0_DEFAULT);
582 	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE1],
583 			   data->zone1_thres_count);
584 	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE2],
585 			   BWMON_THRESHOLD_COUNT_ZONE2_DEFAULT);
586 	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE3],
587 			   data->zone3_thres_count);
588 
589 	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE0],
590 			   BWMON_ZONE_ACTIONS_ZONE0);
591 	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE1],
592 			   BWMON_ZONE_ACTIONS_ZONE1);
593 	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE2],
594 			   BWMON_ZONE_ACTIONS_ZONE2);
595 	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE3],
596 			   BWMON_ZONE_ACTIONS_ZONE3);
597 
598 	bwmon_clear_irq(bwmon);
599 	bwmon_enable(bwmon, BWMON_IRQ_ENABLE_MASK);
600 }
601 
bwmon_intr(int irq,void * dev_id)602 static irqreturn_t bwmon_intr(int irq, void *dev_id)
603 {
604 	struct icc_bwmon *bwmon = dev_id;
605 	unsigned int status, max;
606 	int zone;
607 
608 	if (regmap_field_read(bwmon->regs[F_IRQ_STATUS], &status))
609 		return IRQ_NONE;
610 
611 	status &= BWMON_IRQ_ENABLE_MASK;
612 	if (!status) {
613 		/*
614 		 * Only zone 1 and zone 3 interrupts are enabled but zone 2
615 		 * threshold could be hit and trigger interrupt even if not
616 		 * enabled.
617 		 * Such spurious interrupt might come with valuable max count or
618 		 * not, so solution would be to always check all
619 		 * BWMON_ZONE_MAX() registers to find the highest value.
620 		 * Such case is currently ignored.
621 		 */
622 		return IRQ_NONE;
623 	}
624 
625 	bwmon_disable(bwmon);
626 
627 	zone = get_bitmask_order(status) - 1;
628 	/*
629 	 * Zone max bytes count register returns count units within sampling
630 	 * window.  Downstream kernel for BWMONv4 (called BWMON type 2 in
631 	 * downstream) always increments the max bytes count by one.
632 	 */
633 	if (regmap_field_read(bwmon->regs[F_ZONE0_MAX + zone], &max))
634 		return IRQ_NONE;
635 
636 	max += 1;
637 	max *= bwmon->data->count_unit_kb;
638 	bwmon->target_kbps = mult_frac(max, MSEC_PER_SEC, bwmon->data->sample_ms);
639 
640 	return IRQ_WAKE_THREAD;
641 }
642 
bwmon_intr_thread(int irq,void * dev_id)643 static irqreturn_t bwmon_intr_thread(int irq, void *dev_id)
644 {
645 	struct icc_bwmon *bwmon = dev_id;
646 	unsigned int irq_enable = 0;
647 	struct dev_pm_opp *opp, *target_opp;
648 	unsigned int bw_kbps, up_kbps, down_kbps;
649 
650 	bw_kbps = bwmon->target_kbps;
651 
652 	target_opp = dev_pm_opp_find_bw_ceil(bwmon->dev, &bw_kbps, 0);
653 	if (IS_ERR(target_opp) && PTR_ERR(target_opp) == -ERANGE)
654 		target_opp = dev_pm_opp_find_bw_floor(bwmon->dev, &bw_kbps, 0);
655 
656 	bwmon->target_kbps = bw_kbps;
657 
658 	bw_kbps--;
659 	opp = dev_pm_opp_find_bw_floor(bwmon->dev, &bw_kbps, 0);
660 	if (IS_ERR(opp) && PTR_ERR(opp) == -ERANGE)
661 		down_kbps = bwmon->target_kbps;
662 	else
663 		down_kbps = bw_kbps;
664 
665 	up_kbps = bwmon->target_kbps + 1;
666 
667 	if (bwmon->target_kbps >= bwmon->max_bw_kbps)
668 		irq_enable = BIT(1);
669 	else if (bwmon->target_kbps <= bwmon->min_bw_kbps)
670 		irq_enable = BIT(3);
671 	else
672 		irq_enable = BWMON_IRQ_ENABLE_MASK;
673 
674 	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_HIGH],
675 			    up_kbps);
676 	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_MED],
677 			    down_kbps);
678 	bwmon_clear_counters(bwmon, false);
679 	bwmon_clear_irq(bwmon);
680 	bwmon_enable(bwmon, irq_enable);
681 
682 	if (bwmon->target_kbps == bwmon->current_kbps)
683 		goto out;
684 
685 	dev_pm_opp_set_opp(bwmon->dev, target_opp);
686 	bwmon->current_kbps = bwmon->target_kbps;
687 
688 out:
689 	dev_pm_opp_put(target_opp);
690 	if (!IS_ERR(opp))
691 		dev_pm_opp_put(opp);
692 
693 	return IRQ_HANDLED;
694 }
695 
bwmon_init_regmap(struct platform_device * pdev,struct icc_bwmon * bwmon)696 static int bwmon_init_regmap(struct platform_device *pdev,
697 			     struct icc_bwmon *bwmon)
698 {
699 	struct device *dev = &pdev->dev;
700 	void __iomem *base;
701 	struct regmap *map;
702 	int ret;
703 
704 	/* Map the monitor base */
705 	base = devm_platform_ioremap_resource(pdev, 0);
706 	if (IS_ERR(base))
707 		return dev_err_probe(dev, PTR_ERR(base),
708 				     "failed to map bwmon registers\n");
709 
710 	map = devm_regmap_init_mmio(dev, base, bwmon->data->regmap_cfg);
711 	if (IS_ERR(map))
712 		return dev_err_probe(dev, PTR_ERR(map),
713 				     "failed to initialize regmap\n");
714 
715 	BUILD_BUG_ON(ARRAY_SIZE(msm8998_bwmon_global_reg_fields) != F_NUM_GLOBAL_FIELDS);
716 	BUILD_BUG_ON(ARRAY_SIZE(msm8998_bwmon_reg_fields) != F_NUM_FIELDS);
717 	BUILD_BUG_ON(ARRAY_SIZE(sdm845_cpu_bwmon_reg_fields) != F_NUM_FIELDS);
718 	BUILD_BUG_ON(ARRAY_SIZE(sdm845_llcc_bwmon_reg_fields) != F_NUM_FIELDS);
719 
720 	ret = devm_regmap_field_bulk_alloc(dev, map, bwmon->regs,
721 					   bwmon->data->regmap_fields,
722 					   F_NUM_FIELDS);
723 	if (ret)
724 		return ret;
725 
726 	if (bwmon->data->global_regmap_cfg) {
727 		/* Map the global base, if separate */
728 		base = devm_platform_ioremap_resource(pdev, 1);
729 		if (IS_ERR(base))
730 			return dev_err_probe(dev, PTR_ERR(base),
731 					     "failed to map bwmon global registers\n");
732 
733 		map = devm_regmap_init_mmio(dev, base, bwmon->data->global_regmap_cfg);
734 		if (IS_ERR(map))
735 			return dev_err_probe(dev, PTR_ERR(map),
736 					     "failed to initialize global regmap\n");
737 
738 		ret = devm_regmap_field_bulk_alloc(dev, map, bwmon->global_regs,
739 						   bwmon->data->global_regmap_fields,
740 						   F_NUM_GLOBAL_FIELDS);
741 	}
742 
743 	return ret;
744 }
745 
bwmon_probe(struct platform_device * pdev)746 static int bwmon_probe(struct platform_device *pdev)
747 {
748 	struct device *dev = &pdev->dev;
749 	struct dev_pm_opp *opp;
750 	struct icc_bwmon *bwmon;
751 	int ret;
752 
753 	bwmon = devm_kzalloc(dev, sizeof(*bwmon), GFP_KERNEL);
754 	if (!bwmon)
755 		return -ENOMEM;
756 
757 	bwmon->data = of_device_get_match_data(dev);
758 
759 	ret = bwmon_init_regmap(pdev, bwmon);
760 	if (ret)
761 		return ret;
762 
763 	bwmon->irq = platform_get_irq(pdev, 0);
764 	if (bwmon->irq < 0)
765 		return bwmon->irq;
766 
767 	ret = devm_pm_opp_of_add_table(dev);
768 	if (ret)
769 		return dev_err_probe(dev, ret, "failed to add OPP table\n");
770 
771 	bwmon->max_bw_kbps = UINT_MAX;
772 	opp = dev_pm_opp_find_bw_floor(dev, &bwmon->max_bw_kbps, 0);
773 	if (IS_ERR(opp))
774 		return dev_err_probe(dev, PTR_ERR(opp), "failed to find max peak bandwidth\n");
775 
776 	bwmon->min_bw_kbps = 0;
777 	opp = dev_pm_opp_find_bw_ceil(dev, &bwmon->min_bw_kbps, 0);
778 	if (IS_ERR(opp))
779 		return dev_err_probe(dev, PTR_ERR(opp), "failed to find min peak bandwidth\n");
780 
781 	bwmon->dev = dev;
782 
783 	bwmon_disable(bwmon);
784 	ret = devm_request_threaded_irq(dev, bwmon->irq, bwmon_intr,
785 					bwmon_intr_thread,
786 					IRQF_ONESHOT, dev_name(dev), bwmon);
787 	if (ret)
788 		return dev_err_probe(dev, ret, "failed to request IRQ\n");
789 
790 	platform_set_drvdata(pdev, bwmon);
791 	bwmon_start(bwmon);
792 
793 	return 0;
794 }
795 
bwmon_remove(struct platform_device * pdev)796 static int bwmon_remove(struct platform_device *pdev)
797 {
798 	struct icc_bwmon *bwmon = platform_get_drvdata(pdev);
799 
800 	bwmon_disable(bwmon);
801 
802 	return 0;
803 }
804 
805 static const struct icc_bwmon_data msm8998_bwmon_data = {
806 	.sample_ms = 4,
807 	.count_unit_kb = 1024,
808 	.zone1_thres_count = 16,
809 	.zone3_thres_count = 1,
810 	.quirks = BWMON_HAS_GLOBAL_IRQ,
811 	.regmap_fields = msm8998_bwmon_reg_fields,
812 	.regmap_cfg = &msm8998_bwmon_regmap_cfg,
813 	.global_regmap_fields = msm8998_bwmon_global_reg_fields,
814 	.global_regmap_cfg = &msm8998_bwmon_global_regmap_cfg,
815 };
816 
817 static const struct icc_bwmon_data sdm845_cpu_bwmon_data = {
818 	.sample_ms = 4,
819 	.count_unit_kb = 64,
820 	.zone1_thres_count = 16,
821 	.zone3_thres_count = 1,
822 	.quirks = BWMON_HAS_GLOBAL_IRQ,
823 	.regmap_fields = sdm845_cpu_bwmon_reg_fields,
824 	.regmap_cfg = &sdm845_cpu_bwmon_regmap_cfg,
825 };
826 
827 static const struct icc_bwmon_data sdm845_llcc_bwmon_data = {
828 	.sample_ms = 4,
829 	.count_unit_kb = 1024,
830 	.zone1_thres_count = 16,
831 	.zone3_thres_count = 1,
832 	.regmap_fields = sdm845_llcc_bwmon_reg_fields,
833 	.regmap_cfg = &sdm845_llcc_bwmon_regmap_cfg,
834 };
835 
836 static const struct icc_bwmon_data sc7280_llcc_bwmon_data = {
837 	.sample_ms = 4,
838 	.count_unit_kb = 64,
839 	.zone1_thres_count = 16,
840 	.zone3_thres_count = 1,
841 	.quirks = BWMON_NEEDS_FORCE_CLEAR,
842 	.regmap_fields = sdm845_llcc_bwmon_reg_fields,
843 	.regmap_cfg = &sdm845_llcc_bwmon_regmap_cfg,
844 };
845 
846 static const struct of_device_id bwmon_of_match[] = {
847 	/* BWMONv4, separate monitor and global register spaces */
848 	{ .compatible = "qcom,msm8998-bwmon", .data = &msm8998_bwmon_data },
849 	/* BWMONv4, unified register space */
850 	{ .compatible = "qcom,sdm845-bwmon", .data = &sdm845_cpu_bwmon_data },
851 	/* BWMONv5 */
852 	{ .compatible = "qcom,sdm845-llcc-bwmon", .data = &sdm845_llcc_bwmon_data },
853 	{ .compatible = "qcom,sc7280-llcc-bwmon", .data = &sc7280_llcc_bwmon_data },
854 
855 	/* Compatibles kept for legacy reasons */
856 	{ .compatible = "qcom,sc7280-cpu-bwmon", .data = &sdm845_cpu_bwmon_data },
857 	{ .compatible = "qcom,sc8280xp-cpu-bwmon", .data = &sdm845_cpu_bwmon_data },
858 	{ .compatible = "qcom,sm8550-cpu-bwmon", .data = &sdm845_cpu_bwmon_data },
859 	{}
860 };
861 MODULE_DEVICE_TABLE(of, bwmon_of_match);
862 
863 static struct platform_driver bwmon_driver = {
864 	.probe = bwmon_probe,
865 	.remove = bwmon_remove,
866 	.driver = {
867 		.name = "qcom-bwmon",
868 		.of_match_table = bwmon_of_match,
869 	},
870 };
871 module_platform_driver(bwmon_driver);
872 
873 MODULE_AUTHOR("Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>");
874 MODULE_DESCRIPTION("QCOM BWMON driver");
875 MODULE_LICENSE("GPL");
876