1 /* drivers/devfreq/exynos4210_memorybus.c
2  *
3  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
4  *		http://www.samsung.com/
5  *	MyungJoo Ham <myungjoo.ham@samsung.com>
6  *
7  * EXYNOS4 - Memory/Bus clock frequency scaling support in DEVFREQ framework
8  *	This version supports EXYNOS4210 only. This changes bus frequencies
9  *	and vddint voltages. Exynos4412/4212 should be able to be supported
10  *	with minor modifications.
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License version 2 as
14  * published by the Free Software Foundation.
15  *
16  */
17 
18 #include <linux/io.h>
19 #include <linux/slab.h>
20 #include <linux/mutex.h>
21 #include <linux/suspend.h>
22 #include <linux/pm_opp.h>
23 #include <linux/devfreq.h>
24 #include <linux/platform_device.h>
25 #include <linux/regulator/consumer.h>
26 #include <linux/module.h>
27 
28 #include <mach/map.h>
29 
30 #include "exynos_ppmu.h"
31 #include "exynos4_bus.h"
32 
33 #define MAX_SAFEVOLT	1200000 /* 1.2V */
34 
35 enum exynos4_busf_type {
36 	TYPE_BUSF_EXYNOS4210,
37 	TYPE_BUSF_EXYNOS4x12,
38 };
39 
40 /* Assume that the bus is saturated if the utilization is 40% */
41 #define BUS_SATURATION_RATIO	40
42 
43 enum busclk_level_idx {
44 	LV_0 = 0,
45 	LV_1,
46 	LV_2,
47 	LV_3,
48 	LV_4,
49 	_LV_END
50 };
51 
52 enum exynos_ppmu_idx {
53 	PPMU_DMC0,
54 	PPMU_DMC1,
55 	PPMU_END,
56 };
57 
58 #define EX4210_LV_MAX	LV_2
59 #define EX4x12_LV_MAX	LV_4
60 #define EX4210_LV_NUM	(LV_2 + 1)
61 #define EX4x12_LV_NUM	(LV_4 + 1)
62 
63 /**
64  * struct busfreq_opp_info - opp information for bus
65  * @rate:	Frequency in hertz
66  * @volt:	Voltage in microvolts corresponding to this OPP
67  */
68 struct busfreq_opp_info {
69 	unsigned long rate;
70 	unsigned long volt;
71 };
72 
73 struct busfreq_data {
74 	enum exynos4_busf_type type;
75 	struct device *dev;
76 	struct devfreq *devfreq;
77 	bool disabled;
78 	struct regulator *vdd_int;
79 	struct regulator *vdd_mif; /* Exynos4412/4212 only */
80 	struct busfreq_opp_info curr_oppinfo;
81 	struct busfreq_ppmu_data ppmu_data;
82 
83 	struct notifier_block pm_notifier;
84 	struct mutex lock;
85 
86 	/* Dividers calculated at boot/probe-time */
87 	unsigned int dmc_divtable[_LV_END]; /* DMC0 */
88 	unsigned int top_divtable[_LV_END];
89 };
90 
91 /* 4210 controls clock of mif and voltage of int */
92 static struct bus_opp_table exynos4210_busclk_table[] = {
93 	{LV_0, 400000, 1150000},
94 	{LV_1, 267000, 1050000},
95 	{LV_2, 133000, 1025000},
96 	{0, 0, 0},
97 };
98 
99 /*
100  * MIF is the main control knob clock for Exynos4x12 MIF/INT
101  * clock and voltage of both mif/int are controlled.
102  */
103 static struct bus_opp_table exynos4x12_mifclk_table[] = {
104 	{LV_0, 400000, 1100000},
105 	{LV_1, 267000, 1000000},
106 	{LV_2, 160000, 950000},
107 	{LV_3, 133000, 950000},
108 	{LV_4, 100000, 950000},
109 	{0, 0, 0},
110 };
111 
112 /*
113  * INT is not the control knob of 4x12. LV_x is not meant to represent
114  * the current performance. (MIF does)
115  */
116 static struct bus_opp_table exynos4x12_intclk_table[] = {
117 	{LV_0, 200000, 1000000},
118 	{LV_1, 160000, 950000},
119 	{LV_2, 133000, 925000},
120 	{LV_3, 100000, 900000},
121 	{0, 0, 0},
122 };
123 
124 /* TODO: asv volt definitions are "__initdata"? */
125 /* Some chips have different operating voltages */
126 static unsigned int exynos4210_asv_volt[][EX4210_LV_NUM] = {
127 	{1150000, 1050000, 1050000},
128 	{1125000, 1025000, 1025000},
129 	{1100000, 1000000, 1000000},
130 	{1075000, 975000, 975000},
131 	{1050000, 950000, 950000},
132 };
133 
134 static unsigned int exynos4x12_mif_step_50[][EX4x12_LV_NUM] = {
135 	/* 400      267     160     133     100 */
136 	{1050000, 950000, 900000, 900000, 900000}, /* ASV0 */
137 	{1050000, 950000, 900000, 900000, 900000}, /* ASV1 */
138 	{1050000, 950000, 900000, 900000, 900000}, /* ASV2 */
139 	{1050000, 900000, 900000, 900000, 900000}, /* ASV3 */
140 	{1050000, 900000, 900000, 900000, 850000}, /* ASV4 */
141 	{1050000, 900000, 900000, 850000, 850000}, /* ASV5 */
142 	{1050000, 900000, 850000, 850000, 850000}, /* ASV6 */
143 	{1050000, 900000, 850000, 850000, 850000}, /* ASV7 */
144 	{1050000, 900000, 850000, 850000, 850000}, /* ASV8 */
145 };
146 
147 static unsigned int exynos4x12_int_volt[][EX4x12_LV_NUM] = {
148 	/* 200    160      133     100 */
149 	{1000000, 950000, 925000, 900000}, /* ASV0 */
150 	{975000,  925000, 925000, 900000}, /* ASV1 */
151 	{950000,  925000, 900000, 875000}, /* ASV2 */
152 	{950000,  900000, 900000, 875000}, /* ASV3 */
153 	{925000,  875000, 875000, 875000}, /* ASV4 */
154 	{900000,  850000, 850000, 850000}, /* ASV5 */
155 	{900000,  850000, 850000, 850000}, /* ASV6 */
156 	{900000,  850000, 850000, 850000}, /* ASV7 */
157 	{900000,  850000, 850000, 850000}, /* ASV8 */
158 };
159 
160 /*** Clock Divider Data for Exynos4210 ***/
161 static unsigned int exynos4210_clkdiv_dmc0[][8] = {
162 	/*
163 	 * Clock divider value for following
164 	 * { DIVACP, DIVACP_PCLK, DIVDPHY, DIVDMC, DIVDMCD
165 	 *		DIVDMCP, DIVCOPY2, DIVCORE_TIMERS }
166 	 */
167 
168 	/* DMC L0: 400MHz */
169 	{ 3, 1, 1, 1, 1, 1, 3, 1 },
170 	/* DMC L1: 266.7MHz */
171 	{ 4, 1, 1, 2, 1, 1, 3, 1 },
172 	/* DMC L2: 133MHz */
173 	{ 5, 1, 1, 5, 1, 1, 3, 1 },
174 };
175 static unsigned int exynos4210_clkdiv_top[][5] = {
176 	/*
177 	 * Clock divider value for following
178 	 * { DIVACLK200, DIVACLK100, DIVACLK160, DIVACLK133, DIVONENAND }
179 	 */
180 	/* ACLK200 L0: 200MHz */
181 	{ 3, 7, 4, 5, 1 },
182 	/* ACLK200 L1: 160MHz */
183 	{ 4, 7, 5, 6, 1 },
184 	/* ACLK200 L2: 133MHz */
185 	{ 5, 7, 7, 7, 1 },
186 };
187 static unsigned int exynos4210_clkdiv_lr_bus[][2] = {
188 	/*
189 	 * Clock divider value for following
190 	 * { DIVGDL/R, DIVGPL/R }
191 	 */
192 	/* ACLK_GDL/R L1: 200MHz */
193 	{ 3, 1 },
194 	/* ACLK_GDL/R L2: 160MHz */
195 	{ 4, 1 },
196 	/* ACLK_GDL/R L3: 133MHz */
197 	{ 5, 1 },
198 };
199 
200 /*** Clock Divider Data for Exynos4212/4412 ***/
201 static unsigned int exynos4x12_clkdiv_dmc0[][6] = {
202 	/*
203 	 * Clock divider value for following
204 	 * { DIVACP, DIVACP_PCLK, DIVDPHY, DIVDMC, DIVDMCD
205 	 *              DIVDMCP}
206 	 */
207 
208 	/* DMC L0: 400MHz */
209 	{3, 1, 1, 1, 1, 1},
210 	/* DMC L1: 266.7MHz */
211 	{4, 1, 1, 2, 1, 1},
212 	/* DMC L2: 160MHz */
213 	{5, 1, 1, 4, 1, 1},
214 	/* DMC L3: 133MHz */
215 	{5, 1, 1, 5, 1, 1},
216 	/* DMC L4: 100MHz */
217 	{7, 1, 1, 7, 1, 1},
218 };
219 static unsigned int exynos4x12_clkdiv_dmc1[][6] = {
220 	/*
221 	 * Clock divider value for following
222 	 * { G2DACP, DIVC2C, DIVC2C_ACLK }
223 	 */
224 
225 	/* DMC L0: 400MHz */
226 	{3, 1, 1},
227 	/* DMC L1: 266.7MHz */
228 	{4, 2, 1},
229 	/* DMC L2: 160MHz */
230 	{5, 4, 1},
231 	/* DMC L3: 133MHz */
232 	{5, 5, 1},
233 	/* DMC L4: 100MHz */
234 	{7, 7, 1},
235 };
236 static unsigned int exynos4x12_clkdiv_top[][5] = {
237 	/*
238 	 * Clock divider value for following
239 	 * { DIVACLK266_GPS, DIVACLK100, DIVACLK160,
240 		DIVACLK133, DIVONENAND }
241 	 */
242 
243 	/* ACLK_GDL/R L0: 200MHz */
244 	{2, 7, 4, 5, 1},
245 	/* ACLK_GDL/R L1: 200MHz */
246 	{2, 7, 4, 5, 1},
247 	/* ACLK_GDL/R L2: 160MHz */
248 	{4, 7, 5, 7, 1},
249 	/* ACLK_GDL/R L3: 133MHz */
250 	{4, 7, 5, 7, 1},
251 	/* ACLK_GDL/R L4: 100MHz */
252 	{7, 7, 7, 7, 1},
253 };
254 static unsigned int exynos4x12_clkdiv_lr_bus[][2] = {
255 	/*
256 	 * Clock divider value for following
257 	 * { DIVGDL/R, DIVGPL/R }
258 	 */
259 
260 	/* ACLK_GDL/R L0: 200MHz */
261 	{3, 1},
262 	/* ACLK_GDL/R L1: 200MHz */
263 	{3, 1},
264 	/* ACLK_GDL/R L2: 160MHz */
265 	{4, 1},
266 	/* ACLK_GDL/R L3: 133MHz */
267 	{5, 1},
268 	/* ACLK_GDL/R L4: 100MHz */
269 	{7, 1},
270 };
271 static unsigned int exynos4x12_clkdiv_sclkip[][3] = {
272 	/*
273 	 * Clock divider value for following
274 	 * { DIVMFC, DIVJPEG, DIVFIMC0~3}
275 	 */
276 
277 	/* SCLK_MFC: 200MHz */
278 	{3, 3, 4},
279 	/* SCLK_MFC: 200MHz */
280 	{3, 3, 4},
281 	/* SCLK_MFC: 160MHz */
282 	{4, 4, 5},
283 	/* SCLK_MFC: 133MHz */
284 	{5, 5, 5},
285 	/* SCLK_MFC: 100MHz */
286 	{7, 7, 7},
287 };
288 
289 
exynos4210_set_busclk(struct busfreq_data * data,struct busfreq_opp_info * oppi)290 static int exynos4210_set_busclk(struct busfreq_data *data,
291 				 struct busfreq_opp_info *oppi)
292 {
293 	unsigned int index;
294 	unsigned int tmp;
295 
296 	for (index = LV_0; index < EX4210_LV_NUM; index++)
297 		if (oppi->rate == exynos4210_busclk_table[index].clk)
298 			break;
299 
300 	if (index == EX4210_LV_NUM)
301 		return -EINVAL;
302 
303 	/* Change Divider - DMC0 */
304 	tmp = data->dmc_divtable[index];
305 
306 	__raw_writel(tmp, EXYNOS4_CLKDIV_DMC0);
307 
308 	do {
309 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_DMC0);
310 	} while (tmp & 0x11111111);
311 
312 	/* Change Divider - TOP */
313 	tmp = data->top_divtable[index];
314 
315 	__raw_writel(tmp, EXYNOS4_CLKDIV_TOP);
316 
317 	do {
318 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_TOP);
319 	} while (tmp & 0x11111);
320 
321 	/* Change Divider - LEFTBUS */
322 	tmp = __raw_readl(EXYNOS4_CLKDIV_LEFTBUS);
323 
324 	tmp &= ~(EXYNOS4_CLKDIV_BUS_GDLR_MASK | EXYNOS4_CLKDIV_BUS_GPLR_MASK);
325 
326 	tmp |= ((exynos4210_clkdiv_lr_bus[index][0] <<
327 				EXYNOS4_CLKDIV_BUS_GDLR_SHIFT) |
328 		(exynos4210_clkdiv_lr_bus[index][1] <<
329 				EXYNOS4_CLKDIV_BUS_GPLR_SHIFT));
330 
331 	__raw_writel(tmp, EXYNOS4_CLKDIV_LEFTBUS);
332 
333 	do {
334 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_LEFTBUS);
335 	} while (tmp & 0x11);
336 
337 	/* Change Divider - RIGHTBUS */
338 	tmp = __raw_readl(EXYNOS4_CLKDIV_RIGHTBUS);
339 
340 	tmp &= ~(EXYNOS4_CLKDIV_BUS_GDLR_MASK | EXYNOS4_CLKDIV_BUS_GPLR_MASK);
341 
342 	tmp |= ((exynos4210_clkdiv_lr_bus[index][0] <<
343 				EXYNOS4_CLKDIV_BUS_GDLR_SHIFT) |
344 		(exynos4210_clkdiv_lr_bus[index][1] <<
345 				EXYNOS4_CLKDIV_BUS_GPLR_SHIFT));
346 
347 	__raw_writel(tmp, EXYNOS4_CLKDIV_RIGHTBUS);
348 
349 	do {
350 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_RIGHTBUS);
351 	} while (tmp & 0x11);
352 
353 	return 0;
354 }
355 
exynos4x12_set_busclk(struct busfreq_data * data,struct busfreq_opp_info * oppi)356 static int exynos4x12_set_busclk(struct busfreq_data *data,
357 				 struct busfreq_opp_info *oppi)
358 {
359 	unsigned int index;
360 	unsigned int tmp;
361 
362 	for (index = LV_0; index < EX4x12_LV_NUM; index++)
363 		if (oppi->rate == exynos4x12_mifclk_table[index].clk)
364 			break;
365 
366 	if (index == EX4x12_LV_NUM)
367 		return -EINVAL;
368 
369 	/* Change Divider - DMC0 */
370 	tmp = data->dmc_divtable[index];
371 
372 	__raw_writel(tmp, EXYNOS4_CLKDIV_DMC0);
373 
374 	do {
375 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_DMC0);
376 	} while (tmp & 0x11111111);
377 
378 	/* Change Divider - DMC1 */
379 	tmp = __raw_readl(EXYNOS4_CLKDIV_DMC1);
380 
381 	tmp &= ~(EXYNOS4_CLKDIV_DMC1_G2D_ACP_MASK |
382 		EXYNOS4_CLKDIV_DMC1_C2C_MASK |
383 		EXYNOS4_CLKDIV_DMC1_C2CACLK_MASK);
384 
385 	tmp |= ((exynos4x12_clkdiv_dmc1[index][0] <<
386 				EXYNOS4_CLKDIV_DMC1_G2D_ACP_SHIFT) |
387 		(exynos4x12_clkdiv_dmc1[index][1] <<
388 				EXYNOS4_CLKDIV_DMC1_C2C_SHIFT) |
389 		(exynos4x12_clkdiv_dmc1[index][2] <<
390 				EXYNOS4_CLKDIV_DMC1_C2CACLK_SHIFT));
391 
392 	__raw_writel(tmp, EXYNOS4_CLKDIV_DMC1);
393 
394 	do {
395 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_DMC1);
396 	} while (tmp & 0x111111);
397 
398 	/* Change Divider - TOP */
399 	tmp = __raw_readl(EXYNOS4_CLKDIV_TOP);
400 
401 	tmp &= ~(EXYNOS4_CLKDIV_TOP_ACLK266_GPS_MASK |
402 		EXYNOS4_CLKDIV_TOP_ACLK100_MASK |
403 		EXYNOS4_CLKDIV_TOP_ACLK160_MASK |
404 		EXYNOS4_CLKDIV_TOP_ACLK133_MASK |
405 		EXYNOS4_CLKDIV_TOP_ONENAND_MASK);
406 
407 	tmp |= ((exynos4x12_clkdiv_top[index][0] <<
408 				EXYNOS4_CLKDIV_TOP_ACLK266_GPS_SHIFT) |
409 		(exynos4x12_clkdiv_top[index][1] <<
410 				EXYNOS4_CLKDIV_TOP_ACLK100_SHIFT) |
411 		(exynos4x12_clkdiv_top[index][2] <<
412 				EXYNOS4_CLKDIV_TOP_ACLK160_SHIFT) |
413 		(exynos4x12_clkdiv_top[index][3] <<
414 				EXYNOS4_CLKDIV_TOP_ACLK133_SHIFT) |
415 		(exynos4x12_clkdiv_top[index][4] <<
416 				EXYNOS4_CLKDIV_TOP_ONENAND_SHIFT));
417 
418 	__raw_writel(tmp, EXYNOS4_CLKDIV_TOP);
419 
420 	do {
421 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_TOP);
422 	} while (tmp & 0x11111);
423 
424 	/* Change Divider - LEFTBUS */
425 	tmp = __raw_readl(EXYNOS4_CLKDIV_LEFTBUS);
426 
427 	tmp &= ~(EXYNOS4_CLKDIV_BUS_GDLR_MASK | EXYNOS4_CLKDIV_BUS_GPLR_MASK);
428 
429 	tmp |= ((exynos4x12_clkdiv_lr_bus[index][0] <<
430 				EXYNOS4_CLKDIV_BUS_GDLR_SHIFT) |
431 		(exynos4x12_clkdiv_lr_bus[index][1] <<
432 				EXYNOS4_CLKDIV_BUS_GPLR_SHIFT));
433 
434 	__raw_writel(tmp, EXYNOS4_CLKDIV_LEFTBUS);
435 
436 	do {
437 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_LEFTBUS);
438 	} while (tmp & 0x11);
439 
440 	/* Change Divider - RIGHTBUS */
441 	tmp = __raw_readl(EXYNOS4_CLKDIV_RIGHTBUS);
442 
443 	tmp &= ~(EXYNOS4_CLKDIV_BUS_GDLR_MASK | EXYNOS4_CLKDIV_BUS_GPLR_MASK);
444 
445 	tmp |= ((exynos4x12_clkdiv_lr_bus[index][0] <<
446 				EXYNOS4_CLKDIV_BUS_GDLR_SHIFT) |
447 		(exynos4x12_clkdiv_lr_bus[index][1] <<
448 				EXYNOS4_CLKDIV_BUS_GPLR_SHIFT));
449 
450 	__raw_writel(tmp, EXYNOS4_CLKDIV_RIGHTBUS);
451 
452 	do {
453 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_RIGHTBUS);
454 	} while (tmp & 0x11);
455 
456 	/* Change Divider - MFC */
457 	tmp = __raw_readl(EXYNOS4_CLKDIV_MFC);
458 
459 	tmp &= ~(EXYNOS4_CLKDIV_MFC_MASK);
460 
461 	tmp |= ((exynos4x12_clkdiv_sclkip[index][0] <<
462 				EXYNOS4_CLKDIV_MFC_SHIFT));
463 
464 	__raw_writel(tmp, EXYNOS4_CLKDIV_MFC);
465 
466 	do {
467 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_MFC);
468 	} while (tmp & 0x1);
469 
470 	/* Change Divider - JPEG */
471 	tmp = __raw_readl(EXYNOS4_CLKDIV_CAM1);
472 
473 	tmp &= ~(EXYNOS4_CLKDIV_CAM1_JPEG_MASK);
474 
475 	tmp |= ((exynos4x12_clkdiv_sclkip[index][1] <<
476 				EXYNOS4_CLKDIV_CAM1_JPEG_SHIFT));
477 
478 	__raw_writel(tmp, EXYNOS4_CLKDIV_CAM1);
479 
480 	do {
481 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_CAM1);
482 	} while (tmp & 0x1);
483 
484 	/* Change Divider - FIMC0~3 */
485 	tmp = __raw_readl(EXYNOS4_CLKDIV_CAM);
486 
487 	tmp &= ~(EXYNOS4_CLKDIV_CAM_FIMC0_MASK | EXYNOS4_CLKDIV_CAM_FIMC1_MASK |
488 		EXYNOS4_CLKDIV_CAM_FIMC2_MASK | EXYNOS4_CLKDIV_CAM_FIMC3_MASK);
489 
490 	tmp |= ((exynos4x12_clkdiv_sclkip[index][2] <<
491 				EXYNOS4_CLKDIV_CAM_FIMC0_SHIFT) |
492 		(exynos4x12_clkdiv_sclkip[index][2] <<
493 				EXYNOS4_CLKDIV_CAM_FIMC1_SHIFT) |
494 		(exynos4x12_clkdiv_sclkip[index][2] <<
495 				EXYNOS4_CLKDIV_CAM_FIMC2_SHIFT) |
496 		(exynos4x12_clkdiv_sclkip[index][2] <<
497 				EXYNOS4_CLKDIV_CAM_FIMC3_SHIFT));
498 
499 	__raw_writel(tmp, EXYNOS4_CLKDIV_CAM);
500 
501 	do {
502 		tmp = __raw_readl(EXYNOS4_CLKDIV_STAT_CAM1);
503 	} while (tmp & 0x1111);
504 
505 	return 0;
506 }
507 
exynos4x12_get_intspec(unsigned long mifclk)508 static int exynos4x12_get_intspec(unsigned long mifclk)
509 {
510 	int i = 0;
511 
512 	while (exynos4x12_intclk_table[i].clk) {
513 		if (exynos4x12_intclk_table[i].clk <= mifclk)
514 			return i;
515 		i++;
516 	}
517 
518 	return -EINVAL;
519 }
520 
exynos4_bus_setvolt(struct busfreq_data * data,struct busfreq_opp_info * oppi,struct busfreq_opp_info * oldoppi)521 static int exynos4_bus_setvolt(struct busfreq_data *data,
522 			       struct busfreq_opp_info *oppi,
523 			       struct busfreq_opp_info *oldoppi)
524 {
525 	int err = 0, tmp;
526 	unsigned long volt = oppi->volt;
527 
528 	switch (data->type) {
529 	case TYPE_BUSF_EXYNOS4210:
530 		/* OPP represents DMC clock + INT voltage */
531 		err = regulator_set_voltage(data->vdd_int, volt,
532 					    MAX_SAFEVOLT);
533 		break;
534 	case TYPE_BUSF_EXYNOS4x12:
535 		/* OPP represents MIF clock + MIF voltage */
536 		err = regulator_set_voltage(data->vdd_mif, volt,
537 					    MAX_SAFEVOLT);
538 		if (err)
539 			break;
540 
541 		tmp = exynos4x12_get_intspec(oppi->rate);
542 		if (tmp < 0) {
543 			err = tmp;
544 			regulator_set_voltage(data->vdd_mif,
545 					      oldoppi->volt,
546 					      MAX_SAFEVOLT);
547 			break;
548 		}
549 		err = regulator_set_voltage(data->vdd_int,
550 					    exynos4x12_intclk_table[tmp].volt,
551 					    MAX_SAFEVOLT);
552 		/*  Try to recover */
553 		if (err)
554 			regulator_set_voltage(data->vdd_mif,
555 					      oldoppi->volt,
556 					      MAX_SAFEVOLT);
557 		break;
558 	default:
559 		err = -EINVAL;
560 	}
561 
562 	return err;
563 }
564 
exynos4_bus_target(struct device * dev,unsigned long * _freq,u32 flags)565 static int exynos4_bus_target(struct device *dev, unsigned long *_freq,
566 			      u32 flags)
567 {
568 	int err = 0;
569 	struct platform_device *pdev = container_of(dev, struct platform_device,
570 						    dev);
571 	struct busfreq_data *data = platform_get_drvdata(pdev);
572 	struct dev_pm_opp *opp;
573 	unsigned long freq;
574 	unsigned long old_freq = data->curr_oppinfo.rate;
575 	struct busfreq_opp_info	new_oppinfo;
576 
577 	rcu_read_lock();
578 	opp = devfreq_recommended_opp(dev, _freq, flags);
579 	if (IS_ERR(opp)) {
580 		rcu_read_unlock();
581 		return PTR_ERR(opp);
582 	}
583 	new_oppinfo.rate = dev_pm_opp_get_freq(opp);
584 	new_oppinfo.volt = dev_pm_opp_get_voltage(opp);
585 	rcu_read_unlock();
586 	freq = new_oppinfo.rate;
587 
588 	if (old_freq == freq)
589 		return 0;
590 
591 	dev_dbg(dev, "targeting %lukHz %luuV\n", freq, new_oppinfo.volt);
592 
593 	mutex_lock(&data->lock);
594 
595 	if (data->disabled)
596 		goto out;
597 
598 	if (old_freq < freq)
599 		err = exynos4_bus_setvolt(data, &new_oppinfo,
600 					  &data->curr_oppinfo);
601 	if (err)
602 		goto out;
603 
604 	if (old_freq != freq) {
605 		switch (data->type) {
606 		case TYPE_BUSF_EXYNOS4210:
607 			err = exynos4210_set_busclk(data, &new_oppinfo);
608 			break;
609 		case TYPE_BUSF_EXYNOS4x12:
610 			err = exynos4x12_set_busclk(data, &new_oppinfo);
611 			break;
612 		default:
613 			err = -EINVAL;
614 		}
615 	}
616 	if (err)
617 		goto out;
618 
619 	if (old_freq > freq)
620 		err = exynos4_bus_setvolt(data, &new_oppinfo,
621 					  &data->curr_oppinfo);
622 	if (err)
623 		goto out;
624 
625 	data->curr_oppinfo = new_oppinfo;
626 out:
627 	mutex_unlock(&data->lock);
628 	return err;
629 }
630 
exynos4_bus_get_dev_status(struct device * dev,struct devfreq_dev_status * stat)631 static int exynos4_bus_get_dev_status(struct device *dev,
632 				      struct devfreq_dev_status *stat)
633 {
634 	struct busfreq_data *data = dev_get_drvdata(dev);
635 	struct busfreq_ppmu_data *ppmu_data = &data->ppmu_data;
636 	int busier;
637 
638 	exynos_read_ppmu(ppmu_data);
639 	busier = exynos_get_busier_ppmu(ppmu_data);
640 	stat->current_frequency = data->curr_oppinfo.rate;
641 
642 	/* Number of cycles spent on memory access */
643 	stat->busy_time = ppmu_data->ppmu[busier].count[PPMU_PMNCNT3];
644 	stat->busy_time *= 100 / BUS_SATURATION_RATIO;
645 	stat->total_time = ppmu_data->ppmu[busier].ccnt;
646 
647 	/* If the counters have overflown, retry */
648 	if (ppmu_data->ppmu[busier].ccnt_overflow ||
649 	    ppmu_data->ppmu[busier].count_overflow[0])
650 		return -EAGAIN;
651 
652 	return 0;
653 }
654 
655 static struct devfreq_dev_profile exynos4_devfreq_profile = {
656 	.initial_freq	= 400000,
657 	.polling_ms	= 50,
658 	.target		= exynos4_bus_target,
659 	.get_dev_status	= exynos4_bus_get_dev_status,
660 };
661 
exynos4210_init_tables(struct busfreq_data * data)662 static int exynos4210_init_tables(struct busfreq_data *data)
663 {
664 	u32 tmp;
665 	int mgrp;
666 	int i, err = 0;
667 
668 	tmp = __raw_readl(EXYNOS4_CLKDIV_DMC0);
669 	for (i = LV_0; i < EX4210_LV_NUM; i++) {
670 		tmp &= ~(EXYNOS4_CLKDIV_DMC0_ACP_MASK |
671 			EXYNOS4_CLKDIV_DMC0_ACPPCLK_MASK |
672 			EXYNOS4_CLKDIV_DMC0_DPHY_MASK |
673 			EXYNOS4_CLKDIV_DMC0_DMC_MASK |
674 			EXYNOS4_CLKDIV_DMC0_DMCD_MASK |
675 			EXYNOS4_CLKDIV_DMC0_DMCP_MASK |
676 			EXYNOS4_CLKDIV_DMC0_COPY2_MASK |
677 			EXYNOS4_CLKDIV_DMC0_CORETI_MASK);
678 
679 		tmp |= ((exynos4210_clkdiv_dmc0[i][0] <<
680 					EXYNOS4_CLKDIV_DMC0_ACP_SHIFT) |
681 			(exynos4210_clkdiv_dmc0[i][1] <<
682 					EXYNOS4_CLKDIV_DMC0_ACPPCLK_SHIFT) |
683 			(exynos4210_clkdiv_dmc0[i][2] <<
684 					EXYNOS4_CLKDIV_DMC0_DPHY_SHIFT) |
685 			(exynos4210_clkdiv_dmc0[i][3] <<
686 					EXYNOS4_CLKDIV_DMC0_DMC_SHIFT) |
687 			(exynos4210_clkdiv_dmc0[i][4] <<
688 					EXYNOS4_CLKDIV_DMC0_DMCD_SHIFT) |
689 			(exynos4210_clkdiv_dmc0[i][5] <<
690 					EXYNOS4_CLKDIV_DMC0_DMCP_SHIFT) |
691 			(exynos4210_clkdiv_dmc0[i][6] <<
692 					EXYNOS4_CLKDIV_DMC0_COPY2_SHIFT) |
693 			(exynos4210_clkdiv_dmc0[i][7] <<
694 					EXYNOS4_CLKDIV_DMC0_CORETI_SHIFT));
695 
696 		data->dmc_divtable[i] = tmp;
697 	}
698 
699 	tmp = __raw_readl(EXYNOS4_CLKDIV_TOP);
700 	for (i = LV_0; i <  EX4210_LV_NUM; i++) {
701 		tmp &= ~(EXYNOS4_CLKDIV_TOP_ACLK200_MASK |
702 			EXYNOS4_CLKDIV_TOP_ACLK100_MASK |
703 			EXYNOS4_CLKDIV_TOP_ACLK160_MASK |
704 			EXYNOS4_CLKDIV_TOP_ACLK133_MASK |
705 			EXYNOS4_CLKDIV_TOP_ONENAND_MASK);
706 
707 		tmp |= ((exynos4210_clkdiv_top[i][0] <<
708 					EXYNOS4_CLKDIV_TOP_ACLK200_SHIFT) |
709 			(exynos4210_clkdiv_top[i][1] <<
710 					EXYNOS4_CLKDIV_TOP_ACLK100_SHIFT) |
711 			(exynos4210_clkdiv_top[i][2] <<
712 					EXYNOS4_CLKDIV_TOP_ACLK160_SHIFT) |
713 			(exynos4210_clkdiv_top[i][3] <<
714 					EXYNOS4_CLKDIV_TOP_ACLK133_SHIFT) |
715 			(exynos4210_clkdiv_top[i][4] <<
716 					EXYNOS4_CLKDIV_TOP_ONENAND_SHIFT));
717 
718 		data->top_divtable[i] = tmp;
719 	}
720 
721 	/*
722 	 * TODO: init tmp based on busfreq_data
723 	 * (device-tree or platform-data)
724 	 */
725 	tmp = 0; /* Max voltages for the reliability of the unknown */
726 
727 	pr_debug("ASV Group of Exynos4 is %d\n", tmp);
728 	/* Use merged grouping for voltage */
729 	switch (tmp) {
730 	case 0:
731 		mgrp = 0;
732 		break;
733 	case 1:
734 	case 2:
735 		mgrp = 1;
736 		break;
737 	case 3:
738 	case 4:
739 		mgrp = 2;
740 		break;
741 	case 5:
742 	case 6:
743 		mgrp = 3;
744 		break;
745 	case 7:
746 		mgrp = 4;
747 		break;
748 	default:
749 		pr_warn("Unknown ASV Group. Use max voltage.\n");
750 		mgrp = 0;
751 	}
752 
753 	for (i = LV_0; i < EX4210_LV_NUM; i++)
754 		exynos4210_busclk_table[i].volt = exynos4210_asv_volt[mgrp][i];
755 
756 	for (i = LV_0; i < EX4210_LV_NUM; i++) {
757 		err = dev_pm_opp_add(data->dev, exynos4210_busclk_table[i].clk,
758 			      exynos4210_busclk_table[i].volt);
759 		if (err) {
760 			dev_err(data->dev, "Cannot add opp entries.\n");
761 			return err;
762 		}
763 	}
764 
765 
766 	return 0;
767 }
768 
exynos4x12_init_tables(struct busfreq_data * data)769 static int exynos4x12_init_tables(struct busfreq_data *data)
770 {
771 	unsigned int i;
772 	unsigned int tmp;
773 	int ret;
774 
775 	/* Enable pause function for DREX2 DVFS */
776 	tmp = __raw_readl(EXYNOS4_DMC_PAUSE_CTRL);
777 	tmp |= EXYNOS4_DMC_PAUSE_ENABLE;
778 	__raw_writel(tmp, EXYNOS4_DMC_PAUSE_CTRL);
779 
780 	tmp = __raw_readl(EXYNOS4_CLKDIV_DMC0);
781 
782 	for (i = 0; i <  EX4x12_LV_NUM; i++) {
783 		tmp &= ~(EXYNOS4_CLKDIV_DMC0_ACP_MASK |
784 			EXYNOS4_CLKDIV_DMC0_ACPPCLK_MASK |
785 			EXYNOS4_CLKDIV_DMC0_DPHY_MASK |
786 			EXYNOS4_CLKDIV_DMC0_DMC_MASK |
787 			EXYNOS4_CLKDIV_DMC0_DMCD_MASK |
788 			EXYNOS4_CLKDIV_DMC0_DMCP_MASK);
789 
790 		tmp |= ((exynos4x12_clkdiv_dmc0[i][0] <<
791 					EXYNOS4_CLKDIV_DMC0_ACP_SHIFT) |
792 			(exynos4x12_clkdiv_dmc0[i][1] <<
793 					EXYNOS4_CLKDIV_DMC0_ACPPCLK_SHIFT) |
794 			(exynos4x12_clkdiv_dmc0[i][2] <<
795 					EXYNOS4_CLKDIV_DMC0_DPHY_SHIFT) |
796 			(exynos4x12_clkdiv_dmc0[i][3] <<
797 					EXYNOS4_CLKDIV_DMC0_DMC_SHIFT) |
798 			(exynos4x12_clkdiv_dmc0[i][4] <<
799 					EXYNOS4_CLKDIV_DMC0_DMCD_SHIFT) |
800 			(exynos4x12_clkdiv_dmc0[i][5] <<
801 					EXYNOS4_CLKDIV_DMC0_DMCP_SHIFT));
802 
803 		data->dmc_divtable[i] = tmp;
804 	}
805 
806 	tmp = 0; /* Max voltages for the reliability of the unknown */
807 
808 	if (tmp > 8)
809 		tmp = 0;
810 	pr_debug("ASV Group of Exynos4x12 is %d\n", tmp);
811 
812 	for (i = 0; i < EX4x12_LV_NUM; i++) {
813 		exynos4x12_mifclk_table[i].volt =
814 			exynos4x12_mif_step_50[tmp][i];
815 		exynos4x12_intclk_table[i].volt =
816 			exynos4x12_int_volt[tmp][i];
817 	}
818 
819 	for (i = 0; i < EX4x12_LV_NUM; i++) {
820 		ret = dev_pm_opp_add(data->dev, exynos4x12_mifclk_table[i].clk,
821 			      exynos4x12_mifclk_table[i].volt);
822 		if (ret) {
823 			dev_err(data->dev, "Fail to add opp entries.\n");
824 			return ret;
825 		}
826 	}
827 
828 	return 0;
829 }
830 
exynos4_busfreq_pm_notifier_event(struct notifier_block * this,unsigned long event,void * ptr)831 static int exynos4_busfreq_pm_notifier_event(struct notifier_block *this,
832 		unsigned long event, void *ptr)
833 {
834 	struct busfreq_data *data = container_of(this, struct busfreq_data,
835 						 pm_notifier);
836 	struct dev_pm_opp *opp;
837 	struct busfreq_opp_info	new_oppinfo;
838 	unsigned long maxfreq = ULONG_MAX;
839 	int err = 0;
840 
841 	switch (event) {
842 	case PM_SUSPEND_PREPARE:
843 		/* Set Fastest and Deactivate DVFS */
844 		mutex_lock(&data->lock);
845 
846 		data->disabled = true;
847 
848 		rcu_read_lock();
849 		opp = dev_pm_opp_find_freq_floor(data->dev, &maxfreq);
850 		if (IS_ERR(opp)) {
851 			rcu_read_unlock();
852 			dev_err(data->dev, "%s: unable to find a min freq\n",
853 				__func__);
854 			mutex_unlock(&data->lock);
855 			return PTR_ERR(opp);
856 		}
857 		new_oppinfo.rate = dev_pm_opp_get_freq(opp);
858 		new_oppinfo.volt = dev_pm_opp_get_voltage(opp);
859 		rcu_read_unlock();
860 
861 		err = exynos4_bus_setvolt(data, &new_oppinfo,
862 					  &data->curr_oppinfo);
863 		if (err)
864 			goto unlock;
865 
866 		switch (data->type) {
867 		case TYPE_BUSF_EXYNOS4210:
868 			err = exynos4210_set_busclk(data, &new_oppinfo);
869 			break;
870 		case TYPE_BUSF_EXYNOS4x12:
871 			err = exynos4x12_set_busclk(data, &new_oppinfo);
872 			break;
873 		default:
874 			err = -EINVAL;
875 		}
876 		if (err)
877 			goto unlock;
878 
879 		data->curr_oppinfo = new_oppinfo;
880 unlock:
881 		mutex_unlock(&data->lock);
882 		if (err)
883 			return err;
884 		return NOTIFY_OK;
885 	case PM_POST_RESTORE:
886 	case PM_POST_SUSPEND:
887 		/* Reactivate */
888 		mutex_lock(&data->lock);
889 		data->disabled = false;
890 		mutex_unlock(&data->lock);
891 		return NOTIFY_OK;
892 	}
893 
894 	return NOTIFY_DONE;
895 }
896 
exynos4_busfreq_probe(struct platform_device * pdev)897 static int exynos4_busfreq_probe(struct platform_device *pdev)
898 {
899 	struct busfreq_data *data;
900 	struct busfreq_ppmu_data *ppmu_data;
901 	struct dev_pm_opp *opp;
902 	struct device *dev = &pdev->dev;
903 	int err = 0;
904 
905 	data = devm_kzalloc(&pdev->dev, sizeof(struct busfreq_data), GFP_KERNEL);
906 	if (data == NULL) {
907 		dev_err(dev, "Cannot allocate memory.\n");
908 		return -ENOMEM;
909 	}
910 
911 	ppmu_data = &data->ppmu_data;
912 	ppmu_data->ppmu_end = PPMU_END;
913 	ppmu_data->ppmu = devm_kzalloc(dev,
914 				       sizeof(struct exynos_ppmu) * PPMU_END,
915 				       GFP_KERNEL);
916 	if (!ppmu_data->ppmu) {
917 		dev_err(dev, "Failed to allocate memory for exynos_ppmu\n");
918 		return -ENOMEM;
919 	}
920 
921 	data->type = pdev->id_entry->driver_data;
922 	ppmu_data->ppmu[PPMU_DMC0].hw_base = S5P_VA_DMC0;
923 	ppmu_data->ppmu[PPMU_DMC1].hw_base = S5P_VA_DMC1;
924 	data->pm_notifier.notifier_call = exynos4_busfreq_pm_notifier_event;
925 	data->dev = dev;
926 	mutex_init(&data->lock);
927 
928 	switch (data->type) {
929 	case TYPE_BUSF_EXYNOS4210:
930 		err = exynos4210_init_tables(data);
931 		break;
932 	case TYPE_BUSF_EXYNOS4x12:
933 		err = exynos4x12_init_tables(data);
934 		break;
935 	default:
936 		dev_err(dev, "Cannot determine the device id %d\n", data->type);
937 		err = -EINVAL;
938 	}
939 	if (err) {
940 		dev_err(dev, "Cannot initialize busfreq table %d\n",
941 			     data->type);
942 		return err;
943 	}
944 
945 	data->vdd_int = devm_regulator_get(dev, "vdd_int");
946 	if (IS_ERR(data->vdd_int)) {
947 		dev_err(dev, "Cannot get the regulator \"vdd_int\"\n");
948 		return PTR_ERR(data->vdd_int);
949 	}
950 	if (data->type == TYPE_BUSF_EXYNOS4x12) {
951 		data->vdd_mif = devm_regulator_get(dev, "vdd_mif");
952 		if (IS_ERR(data->vdd_mif)) {
953 			dev_err(dev, "Cannot get the regulator \"vdd_mif\"\n");
954 			return PTR_ERR(data->vdd_mif);
955 		}
956 	}
957 
958 	rcu_read_lock();
959 	opp = dev_pm_opp_find_freq_floor(dev,
960 					 &exynos4_devfreq_profile.initial_freq);
961 	if (IS_ERR(opp)) {
962 		rcu_read_unlock();
963 		dev_err(dev, "Invalid initial frequency %lu kHz.\n",
964 			exynos4_devfreq_profile.initial_freq);
965 		return PTR_ERR(opp);
966 	}
967 	data->curr_oppinfo.rate = dev_pm_opp_get_freq(opp);
968 	data->curr_oppinfo.volt = dev_pm_opp_get_voltage(opp);
969 	rcu_read_unlock();
970 
971 	platform_set_drvdata(pdev, data);
972 
973 	data->devfreq = devm_devfreq_add_device(dev, &exynos4_devfreq_profile,
974 					   "simple_ondemand", NULL);
975 	if (IS_ERR(data->devfreq))
976 		return PTR_ERR(data->devfreq);
977 
978 	/*
979 	 * Start PPMU (Performance Profiling Monitoring Unit) to check
980 	 * utilization of each IP in the Exynos4 SoC.
981 	 */
982 	busfreq_mon_reset(ppmu_data);
983 
984 	/* Register opp_notifier for Exynos4 busfreq */
985 	err = devm_devfreq_register_opp_notifier(dev, data->devfreq);
986 	if (err < 0) {
987 		dev_err(dev, "Failed to register opp notifier\n");
988 		return err;
989 	}
990 
991 	/* Register pm_notifier for Exynos4 busfreq */
992 	err = register_pm_notifier(&data->pm_notifier);
993 	if (err) {
994 		dev_err(dev, "Failed to setup pm notifier\n");
995 		return err;
996 	}
997 
998 	return 0;
999 }
1000 
exynos4_busfreq_remove(struct platform_device * pdev)1001 static int exynos4_busfreq_remove(struct platform_device *pdev)
1002 {
1003 	struct busfreq_data *data = platform_get_drvdata(pdev);
1004 
1005 	/* Unregister all of notifier chain */
1006 	unregister_pm_notifier(&data->pm_notifier);
1007 
1008 	return 0;
1009 }
1010 
1011 #ifdef CONFIG_PM_SLEEP
exynos4_busfreq_resume(struct device * dev)1012 static int exynos4_busfreq_resume(struct device *dev)
1013 {
1014 	struct busfreq_data *data = dev_get_drvdata(dev);
1015 	struct busfreq_ppmu_data *ppmu_data = &data->ppmu_data;
1016 
1017 	busfreq_mon_reset(ppmu_data);
1018 	return 0;
1019 }
1020 #endif
1021 
1022 static SIMPLE_DEV_PM_OPS(exynos4_busfreq_pm_ops, NULL, exynos4_busfreq_resume);
1023 
1024 static const struct platform_device_id exynos4_busfreq_id[] = {
1025 	{ "exynos4210-busfreq", TYPE_BUSF_EXYNOS4210 },
1026 	{ "exynos4412-busfreq", TYPE_BUSF_EXYNOS4x12 },
1027 	{ "exynos4212-busfreq", TYPE_BUSF_EXYNOS4x12 },
1028 	{ },
1029 };
1030 
1031 static struct platform_driver exynos4_busfreq_driver = {
1032 	.probe	= exynos4_busfreq_probe,
1033 	.remove	= exynos4_busfreq_remove,
1034 	.id_table = exynos4_busfreq_id,
1035 	.driver = {
1036 		.name	= "exynos4-busfreq",
1037 		.pm	= &exynos4_busfreq_pm_ops,
1038 	},
1039 };
1040 
exynos4_busfreq_init(void)1041 static int __init exynos4_busfreq_init(void)
1042 {
1043 	return platform_driver_register(&exynos4_busfreq_driver);
1044 }
1045 late_initcall(exynos4_busfreq_init);
1046 
exynos4_busfreq_exit(void)1047 static void __exit exynos4_busfreq_exit(void)
1048 {
1049 	platform_driver_unregister(&exynos4_busfreq_driver);
1050 }
1051 module_exit(exynos4_busfreq_exit);
1052 
1053 MODULE_LICENSE("GPL");
1054 MODULE_DESCRIPTION("EXYNOS4 busfreq driver with devfreq framework");
1055 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1056