1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2014 Freescale Semiconductor, Inc.
4  * Copyright 2020-21 NXP
5  * Copyright 2020 Stephen Carlson <stcarlso@linux.microsoft.com>
6  */
7 
8 #include <common.h>
9 #include <command.h>
10 #include <env.h>
11 #include <i2c.h>
12 #include <irq_func.h>
13 #include <log.h>
14 #include <asm/io.h>
15 #ifdef CONFIG_FSL_LSCH2
16 #include <asm/arch/immap_lsch2.h>
17 #elif defined(CONFIG_FSL_LSCH3)
18 #include <asm/arch/immap_lsch3.h>
19 #else
20 #include <asm/immap_85xx.h>
21 #endif
22 #include <linux/delay.h>
23 #include "i2c_common.h"
24 #include "vid.h"
25 
26 #ifndef I2C_VOL_MONITOR_BUS
27 #define I2C_VOL_MONITOR_BUS                    0
28 #endif
29 
30 /* Voltages are generally handled in mV to keep them as integers */
31 #define MV_PER_V 1000
32 
33 /*
34  * Select the channel on the I2C mux (on some NXP boards) that contains
35  * the voltage regulator to use for VID. Return 0 for success or nonzero
36  * for failure.
37  */
i2c_multiplexer_select_vid_channel(u8 channel)38 int __weak i2c_multiplexer_select_vid_channel(u8 channel)
39 {
40 	return 0;
41 }
42 
43 /*
44  * Compensate for a board specific voltage drop between regulator and SoC.
45  * Returns the voltage offset in mV.
46  */
board_vdd_drop_compensation(void)47 int __weak board_vdd_drop_compensation(void)
48 {
49 	return 0;
50 }
51 
52 /*
53  * Performs any board specific adjustments after the VID voltage has been
54  * set. Return 0 for success or nonzero for failure.
55  */
board_adjust_vdd(int vdd)56 int __weak board_adjust_vdd(int vdd)
57 {
58 	return 0;
59 }
60 
61 /*
62  * Processor specific method of converting the fuse value read from VID
63  * registers into the core voltage to supply. Return the voltage in mV.
64  */
soc_get_fuse_vid(int vid_index)65 u16 __weak soc_get_fuse_vid(int vid_index)
66 {
67 	/* Default VDD for Layerscape Chassis 1 devices */
68 	static const u16 vdd[32] = {
69 		0,      /* unused */
70 		9875,   /* 0.9875V */
71 		9750,
72 		9625,
73 		9500,
74 		9375,
75 		9250,
76 		9125,
77 		9000,
78 		8875,
79 		8750,
80 		8625,
81 		8500,
82 		8375,
83 		8250,
84 		8125,
85 		10000,  /* 1.0000V */
86 		10125,
87 		10250,
88 		10375,
89 		10500,
90 		10625,
91 		10750,
92 		10875,
93 		11000,
94 		0,      /* reserved */
95 	};
96 	return vdd[vid_index];
97 }
98 
99 #ifndef I2C_VOL_MONITOR_ADDR
100 #define I2C_VOL_MONITOR_ADDR                    0
101 #endif
102 
103 #if defined(CONFIG_VOL_MONITOR_IR36021_SET) || \
104 	defined(CONFIG_VOL_MONITOR_IR36021_READ)
105 /*
106  * Get the i2c address configuration for the IR regulator chip
107  *
108  * There are some variance in the RDB HW regarding the I2C address configuration
109  * for the IR regulator chip, which is likely a problem of external resistor
110  * accuracy. So we just check each address in a hopefully non-intrusive mode
111  * and use the first one that seems to work
112  *
113  * The IR chip can show up under the following addresses:
114  * 0x08 (Verified on T1040RDB-PA,T4240RDB-PB,X-T4240RDB-16GPA)
115  * 0x09 (Verified on T1040RDB-PA)
116  * 0x38 (Verified on T2080QDS, T2081QDS, T4240RDB)
117  */
find_ir_chip_on_i2c(void)118 static int find_ir_chip_on_i2c(void)
119 {
120 	int i2caddress, ret, i;
121 	u8 mfrID;
122 	const int ir_i2c_addr[] = {0x38, 0x08, 0x09};
123 	DEVICE_HANDLE_T dev;
124 
125 	/* Check all the address */
126 	for (i = 0; i < (sizeof(ir_i2c_addr)/sizeof(ir_i2c_addr[0])); i++) {
127 		i2caddress = ir_i2c_addr[i];
128 		ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
129 		if (!ret) {
130 			ret = I2C_READ(dev, IR36021_MFR_ID_OFFSET,
131 				       (void *)&mfrID, sizeof(mfrID));
132 			/* If manufacturer ID matches the IR36021 */
133 			if (!ret && mfrID == IR36021_MFR_ID)
134 				return i2caddress;
135 		}
136 	}
137 	return -1;
138 }
139 #endif
140 
141 /* Maximum loop count waiting for new voltage to take effect */
142 #define MAX_LOOP_WAIT_NEW_VOL		100
143 /* Maximum loop count waiting for the voltage to be stable */
144 #define MAX_LOOP_WAIT_VOL_STABLE	100
145 /*
146  * read_voltage from sensor on I2C bus
147  * We use average of 4 readings, waiting for WAIT_FOR_ADC before
148  * another reading
149  */
150 #define NUM_READINGS    4       /* prefer to be power of 2 for efficiency */
151 
152 /* If an INA220 chip is available, we can use it to read back the voltage
153  * as it may have a higher accuracy than the IR chip for the same purpose
154  */
155 #ifdef CONFIG_VOL_MONITOR_INA220
156 #define WAIT_FOR_ADC	532	/* wait for 532 microseconds for ADC */
157 #define ADC_MIN_ACCURACY	4
158 #else
159 #define WAIT_FOR_ADC	138	/* wait for 138 microseconds for ADC */
160 #define ADC_MIN_ACCURACY	4
161 #endif
162 
163 #ifdef CONFIG_VOL_MONITOR_INA220
read_voltage_from_INA220(int i2caddress)164 static int read_voltage_from_INA220(int i2caddress)
165 {
166 	int i, ret, voltage_read = 0;
167 	u16 vol_mon;
168 	u8 buf[2];
169 	DEVICE_HANDLE_T dev;
170 
171 	/* Open device handle */
172 	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
173 	if (ret)
174 		return ret;
175 
176 	for (i = 0; i < NUM_READINGS; i++) {
177 		ret = I2C_READ(dev, I2C_VOL_MONITOR_BUS_V_OFFSET,
178 			       (void *)&buf[0], sizeof(buf));
179 		if (ret) {
180 			printf("VID: failed to read core voltage\n");
181 			return ret;
182 		}
183 
184 		vol_mon = (buf[0] << 8) | buf[1];
185 		if (vol_mon & I2C_VOL_MONITOR_BUS_V_OVF) {
186 			printf("VID: Core voltage sensor error\n");
187 			return -1;
188 		}
189 
190 		debug("VID: bus voltage reads 0x%04x\n", vol_mon);
191 		/* LSB = 4mv */
192 		voltage_read += (vol_mon >> I2C_VOL_MONITOR_BUS_V_SHIFT) * 4;
193 		udelay(WAIT_FOR_ADC);
194 	}
195 
196 	/* calculate the average */
197 	voltage_read /= NUM_READINGS;
198 
199 	return voltage_read;
200 }
201 #endif
202 
203 #ifdef CONFIG_VOL_MONITOR_IR36021_READ
204 /* read voltage from IR */
read_voltage_from_IR(int i2caddress)205 static int read_voltage_from_IR(int i2caddress)
206 {
207 	int i, ret, voltage_read = 0;
208 	u16 vol_mon;
209 	u8 buf;
210 	DEVICE_HANDLE_T dev;
211 
212 	/* Open device handle */
213 	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
214 	if (ret)
215 		return ret;
216 
217 	for (i = 0; i < NUM_READINGS; i++) {
218 		ret = I2C_READ(dev, IR36021_LOOP1_VOUT_OFFSET, (void *)&buf,
219 			       sizeof(buf));
220 		if (ret) {
221 			printf("VID: failed to read core voltage\n");
222 			return ret;
223 		}
224 		vol_mon = buf;
225 		if (!vol_mon) {
226 			printf("VID: Core voltage sensor error\n");
227 			return -1;
228 		}
229 		debug("VID: bus voltage reads 0x%02x\n", vol_mon);
230 		/* Resolution is 1/128V. We scale up here to get 1/128mV
231 		 * and divide at the end
232 		 */
233 		voltage_read += vol_mon * MV_PER_V;
234 		udelay(WAIT_FOR_ADC);
235 	}
236 	/* Scale down to the real mV as IR resolution is 1/128V, rounding up */
237 	voltage_read = DIV_ROUND_UP(voltage_read, 128);
238 
239 	/* calculate the average */
240 	voltage_read /= NUM_READINGS;
241 
242 	/* Compensate for a board specific voltage drop between regulator and
243 	 * SoC before converting into an IR VID value
244 	 */
245 	voltage_read -= board_vdd_drop_compensation();
246 
247 	return voltage_read;
248 }
249 #endif
250 
251 #if defined(CONFIG_VOL_MONITOR_ISL68233_READ) || \
252 	defined(CONFIG_VOL_MONITOR_LTC3882_READ) || \
253 	defined(CONFIG_VOL_MONITOR_ISL68233_SET) || \
254 	defined(CONFIG_VOL_MONITOR_LTC3882_SET)
255 
256 /*
257  * The message displayed if the VOUT exponent causes a resolution
258  * worse than 1.0 V (if exponent is >= 0).
259  */
260 #define VOUT_WARNING "VID: VOUT_MODE exponent has resolution worse than 1 V!\n"
261 
262 /* Checks the PMBus voltage monitor for the format used for voltage values */
get_pmbus_multiplier(DEVICE_HANDLE_T dev)263 static int get_pmbus_multiplier(DEVICE_HANDLE_T dev)
264 {
265 	u8 mode;
266 	int exponent, multiplier, ret;
267 
268 	ret = I2C_READ(dev, PMBUS_CMD_VOUT_MODE, &mode, sizeof(mode));
269 	if (ret) {
270 		printf("VID: unable to determine voltage multiplier\n");
271 		return 1;
272 	}
273 
274 	/* Upper 3 bits is mode, lower 5 bits is exponent */
275 	exponent = (int)mode & 0x1F;
276 	mode >>= 5;
277 	switch (mode) {
278 	case 0:
279 		/* Linear, 5 bit twos component exponent */
280 		if (exponent & 0x10) {
281 			multiplier = 1 << (16 - (exponent & 0xF));
282 		} else {
283 			/* If exponent is >= 0, then resolution is 1 V! */
284 			printf(VOUT_WARNING);
285 			multiplier = 1;
286 		}
287 		break;
288 	case 1:
289 		/* VID code identifier */
290 		printf("VID: custom VID codes are not supported\n");
291 		multiplier = MV_PER_V;
292 		break;
293 	default:
294 		/* Direct, in mV */
295 		multiplier = MV_PER_V;
296 		break;
297 	}
298 
299 	debug("VID: calculated multiplier is %d\n", multiplier);
300 	return multiplier;
301 }
302 #endif
303 
304 #if defined(CONFIG_VOL_MONITOR_ISL68233_READ) || \
305 	defined(CONFIG_VOL_MONITOR_LTC3882_READ)
read_voltage_from_pmbus(int i2caddress)306 static int read_voltage_from_pmbus(int i2caddress)
307 {
308 	int ret, multiplier, vout;
309 	u8 channel = PWM_CHANNEL0;
310 	u16 vcode;
311 	DEVICE_HANDLE_T dev;
312 
313 	/* Open device handle */
314 	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
315 	if (ret)
316 		return ret;
317 
318 	/* Select the right page */
319 	ret = I2C_WRITE(dev, PMBUS_CMD_PAGE, &channel, sizeof(channel));
320 	if (ret) {
321 		printf("VID: failed to select VDD page %d\n", channel);
322 		return ret;
323 	}
324 
325 	/* VOUT is little endian */
326 	ret = I2C_READ(dev, PMBUS_CMD_READ_VOUT, (void *)&vcode, sizeof(vcode));
327 	if (ret) {
328 		printf("VID: failed to read core voltage\n");
329 		return ret;
330 	}
331 
332 	/* Scale down to the real mV */
333 	multiplier = get_pmbus_multiplier(dev);
334 	vout = (int)vcode;
335 	/* Multiplier 1000 (direct mode) requires no change to convert */
336 	if (multiplier != MV_PER_V)
337 		vout = DIV_ROUND_UP(vout * MV_PER_V, multiplier);
338 	return vout - board_vdd_drop_compensation();
339 }
340 #endif
341 
read_voltage(int i2caddress)342 static int read_voltage(int i2caddress)
343 {
344 	int voltage_read;
345 #ifdef CONFIG_VOL_MONITOR_INA220
346 	voltage_read = read_voltage_from_INA220(I2C_VOL_MONITOR_ADDR);
347 #elif defined CONFIG_VOL_MONITOR_IR36021_READ
348 	voltage_read = read_voltage_from_IR(i2caddress);
349 #elif defined(CONFIG_VOL_MONITOR_ISL68233_READ) || \
350 	  defined(CONFIG_VOL_MONITOR_LTC3882_READ)
351 	voltage_read = read_voltage_from_pmbus(i2caddress);
352 #else
353 	voltage_read = -1;
354 #endif
355 	return voltage_read;
356 }
357 
358 #ifdef CONFIG_VOL_MONITOR_IR36021_SET
359 /*
360  * We need to calculate how long before the voltage stops to drop
361  * or increase. It returns with the loop count. Each loop takes
362  * several readings (WAIT_FOR_ADC)
363  */
wait_for_new_voltage(int vdd,int i2caddress)364 static int wait_for_new_voltage(int vdd, int i2caddress)
365 {
366 	int timeout, vdd_current;
367 
368 	vdd_current = read_voltage(i2caddress);
369 	/* wait until voltage starts to reach the target. Voltage slew
370 	 * rates by typical regulators will always lead to stable readings
371 	 * within each fairly long ADC interval in comparison to the
372 	 * intended voltage delta change until the target voltage is
373 	 * reached. The fairly small voltage delta change to any target
374 	 * VID voltage also means that this function will always complete
375 	 * within few iterations. If the timeout was ever reached, it would
376 	 * point to a serious failure in the regulator system.
377 	 */
378 	for (timeout = 0;
379 	     abs(vdd - vdd_current) > (IR_VDD_STEP_UP + IR_VDD_STEP_DOWN) &&
380 	     timeout < MAX_LOOP_WAIT_NEW_VOL; timeout++) {
381 		vdd_current = read_voltage(i2caddress);
382 	}
383 	if (timeout >= MAX_LOOP_WAIT_NEW_VOL) {
384 		printf("VID: Voltage adjustment timeout\n");
385 		return -1;
386 	}
387 	return timeout;
388 }
389 
390 /*
391  * Blocks and reads the VID voltage until it stabilizes, or the
392  * timeout expires
393  */
wait_for_voltage_stable(int i2caddress)394 static int wait_for_voltage_stable(int i2caddress)
395 {
396 	int timeout, vdd_current, vdd;
397 
398 	vdd = read_voltage(i2caddress);
399 	udelay(NUM_READINGS * WAIT_FOR_ADC);
400 
401 	vdd_current = read_voltage(i2caddress);
402 	/*
403 	 * The maximum timeout is
404 	 * MAX_LOOP_WAIT_VOL_STABLE * NUM_READINGS * WAIT_FOR_ADC
405 	 */
406 	for (timeout = MAX_LOOP_WAIT_VOL_STABLE;
407 	     abs(vdd - vdd_current) > ADC_MIN_ACCURACY &&
408 	     timeout > 0; timeout--) {
409 		vdd = vdd_current;
410 		udelay(NUM_READINGS * WAIT_FOR_ADC);
411 		vdd_current = read_voltage(i2caddress);
412 	}
413 	if (timeout == 0)
414 		return -1;
415 	return vdd_current;
416 }
417 
418 /* Sets the VID voltage using the IR36021 */
set_voltage_to_IR(int i2caddress,int vdd)419 static int set_voltage_to_IR(int i2caddress, int vdd)
420 {
421 	int wait, vdd_last;
422 	int ret;
423 	u8 vid;
424 	DEVICE_HANDLE_T dev;
425 
426 	/* Open device handle */
427 	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
428 	if (ret)
429 		return ret;
430 
431 	/* Compensate for a board specific voltage drop between regulator and
432 	 * SoC before converting into an IR VID value
433 	 */
434 	vdd += board_vdd_drop_compensation();
435 #ifdef CONFIG_FSL_LSCH2
436 	vid = DIV_ROUND_UP(vdd - 265, 5);
437 #else
438 	vid = DIV_ROUND_UP(vdd - 245, 5);
439 #endif
440 
441 	ret = I2C_WRITE(dev, IR36021_LOOP1_MANUAL_ID_OFFSET, (void *)&vid,
442 			sizeof(vid));
443 	if (ret) {
444 		printf("VID: failed to write new voltage\n");
445 		return -1;
446 	}
447 	wait = wait_for_new_voltage(vdd, i2caddress);
448 	if (wait < 0)
449 		return -1;
450 	debug("VID: Waited %d us\n", wait * NUM_READINGS * WAIT_FOR_ADC);
451 
452 	vdd_last = wait_for_voltage_stable(i2caddress);
453 	if (vdd_last < 0)
454 		return -1;
455 	debug("VID: Current voltage is %d mV\n", vdd_last);
456 	return vdd_last;
457 }
458 #endif
459 
460 #if defined(CONFIG_VOL_MONITOR_ISL68233_SET) || \
461 	defined(CONFIG_VOL_MONITOR_LTC3882_SET)
set_voltage_to_pmbus(int i2caddress,int vdd)462 static int set_voltage_to_pmbus(int i2caddress, int vdd)
463 {
464 	int ret, vdd_last, vdd_target = vdd;
465 	int count = MAX_LOOP_WAIT_NEW_VOL, temp = 0, multiplier;
466 	unsigned char value;
467 
468 	/* The data to be sent with the PMBus command PAGE_PLUS_WRITE */
469 	u8 buffer[5] = { 0x04, PWM_CHANNEL0, PMBUS_CMD_VOUT_COMMAND, 0, 0 };
470 	DEVICE_HANDLE_T dev;
471 
472 	/* Open device handle */
473 	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
474 	if (ret)
475 		return ret;
476 
477 	/* Scale up to the proper value for the VOUT command, little endian */
478 	multiplier = get_pmbus_multiplier(dev);
479 	vdd += board_vdd_drop_compensation();
480 	if (multiplier != MV_PER_V)
481 		vdd = DIV_ROUND_UP(vdd * multiplier, MV_PER_V);
482 	buffer[3] = vdd & 0xFF;
483 	buffer[4] = (vdd & 0xFF00) >> 8;
484 
485 	/* Check write protect state */
486 	ret = I2C_READ(dev, PMBUS_CMD_WRITE_PROTECT, (void *)&value,
487 		       sizeof(value));
488 	if (ret)
489 		goto exit;
490 
491 	if (value != EN_WRITE_ALL_CMD) {
492 		value = EN_WRITE_ALL_CMD;
493 		ret = I2C_WRITE(dev, PMBUS_CMD_WRITE_PROTECT,
494 				(void *)&value, sizeof(value));
495 		if (ret)
496 			goto exit;
497 	}
498 
499 	/* Write the desired voltage code to the regulator */
500 	ret = I2C_WRITE(dev, PMBUS_CMD_PAGE_PLUS_WRITE, (void *)&buffer[0],
501 			sizeof(buffer));
502 	if (ret) {
503 		printf("VID: I2C failed to write to the voltage regulator\n");
504 		return -1;
505 	}
506 
507 exit:
508 	/* Wait for the voltage to get to the desired value */
509 	do {
510 		vdd_last = read_voltage_from_pmbus(i2caddress);
511 		if (vdd_last < 0) {
512 			printf("VID: Couldn't read sensor abort VID adjust\n");
513 			return -1;
514 		}
515 		count--;
516 		temp = vdd_last - vdd_target;
517 	} while ((abs(temp) > 2)  && (count > 0));
518 
519 	return vdd_last;
520 }
521 #endif
522 
set_voltage(int i2caddress,int vdd)523 static int set_voltage(int i2caddress, int vdd)
524 {
525 	int vdd_last = -1;
526 
527 #ifdef CONFIG_VOL_MONITOR_IR36021_SET
528 	vdd_last = set_voltage_to_IR(i2caddress, vdd);
529 #elif defined(CONFIG_VOL_MONITOR_ISL68233_SET) || \
530 	  defined(CONFIG_VOL_MONITOR_LTC3882_SET)
531 	vdd_last = set_voltage_to_pmbus(i2caddress, vdd);
532 #else
533 	#error Specific voltage monitor must be defined
534 #endif
535 	return vdd_last;
536 }
537 
adjust_vdd(ulong vdd_override)538 int adjust_vdd(ulong vdd_override)
539 {
540 	int re_enable = disable_interrupts();
541 #if defined(CONFIG_FSL_LSCH2) || defined(CONFIG_FSL_LSCH3)
542 	struct ccsr_gur *gur = (void *)(CFG_SYS_FSL_GUTS_ADDR);
543 #else
544 	ccsr_gur_t __iomem *gur =
545 		(void __iomem *)(CFG_SYS_MPC85xx_GUTS_ADDR);
546 #endif
547 	u8 vid;
548 	u32 fusesr;
549 	int vdd_current, vdd_last, vdd_target;
550 	int ret, i2caddress = I2C_VOL_MONITOR_ADDR;
551 	unsigned long vdd_string_override;
552 	char *vdd_string;
553 
554 #if defined(CONFIG_VOL_MONITOR_IR36021_SET) || \
555 	defined(CONFIG_VOL_MONITOR_IR36021_READ)
556 	u8 buf;
557 	DEVICE_HANDLE_T dev;
558 #endif
559 
560 	/*
561 	 * VID is used according to the table below
562 	 *                ---------------------------------------
563 	 *                |                DA_V                 |
564 	 *                |-------------------------------------|
565 	 *                | 5b00000 | 5b00001-5b11110 | 5b11111 |
566 	 * ---------------+---------+-----------------+---------|
567 	 * | D | 5b00000  | NO VID  | VID = DA_V      | NO VID  |
568 	 * | A |----------+---------+-----------------+---------|
569 	 * | _ | 5b00001  |VID =    | VID =           |VID =    |
570 	 * | V |   ~      | DA_V_ALT|   DA_V_ALT      | DA_A_VLT|
571 	 * | _ | 5b11110  |         |                 |         |
572 	 * | A |----------+---------+-----------------+---------|
573 	 * | L | 5b11111  | No VID  | VID = DA_V      | NO VID  |
574 	 * | T |          |         |                 |         |
575 	 * ------------------------------------------------------
576 	 */
577 #if defined(CONFIG_FSL_LSCH3)
578 	fusesr = in_le32(&gur->dcfg_fusesr);
579 	vid = (fusesr >> FSL_CHASSIS3_DCFG_FUSESR_ALTVID_SHIFT) &
580 	       FSL_CHASSIS3_DCFG_FUSESR_ALTVID_MASK;
581 	if (vid == 0 || vid == FSL_CHASSIS3_DCFG_FUSESR_ALTVID_MASK) {
582 		vid = (fusesr >> FSL_CHASSIS3_DCFG_FUSESR_VID_SHIFT) &
583 		       FSL_CHASSIS3_DCFG_FUSESR_VID_MASK;
584 	}
585 #elif defined(CONFIG_FSL_LSCH2)
586 	fusesr = in_be32(&gur->dcfg_fusesr);
587 	vid = (fusesr >> FSL_CHASSIS2_DCFG_FUSESR_ALTVID_SHIFT) &
588 	       FSL_CHASSIS2_DCFG_FUSESR_ALTVID_MASK;
589 	if (vid == 0 || vid == FSL_CHASSIS2_DCFG_FUSESR_ALTVID_MASK) {
590 		vid = (fusesr >> FSL_CHASSIS2_DCFG_FUSESR_VID_SHIFT) &
591 		       FSL_CHASSIS2_DCFG_FUSESR_VID_MASK;
592 	}
593 #else
594 	fusesr = in_be32(&gur->dcfg_fusesr);
595 	vid = (fusesr >> FSL_CORENET_DCFG_FUSESR_ALTVID_SHIFT) &
596 	       FSL_CORENET_DCFG_FUSESR_ALTVID_MASK;
597 	if (vid == 0 || vid == FSL_CORENET_DCFG_FUSESR_ALTVID_MASK) {
598 		vid = (fusesr >> FSL_CORENET_DCFG_FUSESR_VID_SHIFT) &
599 		       FSL_CORENET_DCFG_FUSESR_VID_MASK;
600 	}
601 #endif
602 	vdd_target = soc_get_fuse_vid((int)vid);
603 
604 	ret = i2c_multiplexer_select_vid_channel(I2C_MUX_CH_VOL_MONITOR);
605 	if (ret) {
606 		debug("VID: I2C failed to switch channel\n");
607 		ret = -1;
608 		goto exit;
609 	}
610 
611 #if defined(CONFIG_VOL_MONITOR_IR36021_SET) || \
612 	defined(CONFIG_VOL_MONITOR_IR36021_READ)
613 	ret = find_ir_chip_on_i2c();
614 	if (ret < 0) {
615 		printf("VID: Could not find voltage regulator on I2C.\n");
616 		ret = -1;
617 		goto exit;
618 	} else {
619 		i2caddress = ret;
620 		debug("VID: IR Chip found on I2C address 0x%02x\n", i2caddress);
621 	}
622 
623 	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
624 	if (ret)
625 		return ret;
626 
627 	/* check IR chip work on Intel mode */
628 	ret = I2C_READ(dev, IR36021_INTEL_MODE_OFFSET, (void *)&buf,
629 		       sizeof(buf));
630 	if (ret) {
631 		printf("VID: failed to read IR chip mode.\n");
632 		ret = -1;
633 		goto exit;
634 	}
635 	if ((buf & IR36021_MODE_MASK) != IR36021_INTEL_MODE) {
636 		printf("VID: IR Chip is not used in Intel mode.\n");
637 		ret = -1;
638 		goto exit;
639 	}
640 #endif
641 
642 	/* check override variable for overriding VDD */
643 	vdd_string = env_get(CONFIG_VID_FLS_ENV);
644 	debug("VID: Initial VDD value is %d mV\n",
645 	      DIV_ROUND_UP(vdd_target, 10));
646 	if (vdd_override == 0 && vdd_string &&
647 	    !strict_strtoul(vdd_string, 10, &vdd_string_override))
648 		vdd_override = vdd_string_override;
649 	if (vdd_override >= VDD_MV_MIN && vdd_override <= VDD_MV_MAX) {
650 		vdd_target = vdd_override * 10; /* convert to 1/10 mV */
651 		debug("VID: VDD override is %lu\n", vdd_override);
652 	} else if (vdd_override != 0) {
653 		printf("VID: Invalid VDD value.\n");
654 	}
655 	if (vdd_target == 0) {
656 		debug("VID: VID not used\n");
657 		ret = 0;
658 		goto exit;
659 	} else {
660 		/* divide and round up by 10 to get a value in mV */
661 		vdd_target = DIV_ROUND_UP(vdd_target, 10);
662 		debug("VID: vid = %d mV\n", vdd_target);
663 	}
664 
665 	/*
666 	 * Read voltage monitor to check real voltage.
667 	 */
668 	vdd_last = read_voltage(i2caddress);
669 	if (vdd_last < 0) {
670 		printf("VID: Couldn't read sensor abort VID adjustment\n");
671 		ret = -1;
672 		goto exit;
673 	}
674 	vdd_current = vdd_last;
675 	debug("VID: Core voltage is currently at %d mV\n", vdd_last);
676 
677 #if defined(CONFIG_VOL_MONITOR_LTC3882_SET) || \
678 	defined(CONFIG_VOL_MONITOR_ISL68233_SET)
679 	/* Set the target voltage */
680 	vdd_current = set_voltage(i2caddress, vdd_target);
681 	vdd_last = vdd_current;
682 #else
683 	/*
684 	  * Adjust voltage to at or one step above target.
685 	  * As measurements are less precise than setting the values
686 	  * we may run through dummy steps that cancel each other
687 	  * when stepping up and then down.
688 	  */
689 	while (vdd_last > 0 &&
690 	       vdd_last < vdd_target) {
691 		vdd_current += IR_VDD_STEP_UP;
692 		vdd_last = set_voltage(i2caddress, vdd_current);
693 	}
694 	while (vdd_last > 0 &&
695 	       vdd_last > vdd_target + (IR_VDD_STEP_DOWN - 1)) {
696 		vdd_current -= IR_VDD_STEP_DOWN;
697 		vdd_last = set_voltage(i2caddress, vdd_current);
698 	}
699 #endif
700 
701 	/* Board specific adjustments */
702 	if (board_adjust_vdd(vdd_target) < 0) {
703 		ret = -1;
704 		goto exit;
705 	}
706 
707 	if (vdd_last > 0)
708 		printf("VID: Core voltage after adjustment is at %d mV\n",
709 		       vdd_last);
710 	else
711 		ret = -1;
712 exit:
713 	if (re_enable)
714 		enable_interrupts();
715 
716 	i2c_multiplexer_select_vid_channel(I2C_MUX_CH_DEFAULT);
717 
718 	return ret;
719 }
720 
print_vdd(void)721 static int print_vdd(void)
722 {
723 	int vdd_last, ret, i2caddress = I2C_VOL_MONITOR_ADDR;
724 
725 	ret = i2c_multiplexer_select_vid_channel(I2C_MUX_CH_VOL_MONITOR);
726 	if (ret) {
727 		debug("VID : I2c failed to switch channel\n");
728 		return -1;
729 	}
730 #if defined(CONFIG_VOL_MONITOR_IR36021_SET) || \
731 	defined(CONFIG_VOL_MONITOR_IR36021_READ)
732 	ret = find_ir_chip_on_i2c();
733 	if (ret < 0) {
734 		printf("VID: Could not find voltage regulator on I2C.\n");
735 		goto exit;
736 	} else {
737 		i2caddress = ret;
738 		debug("VID: IR Chip found on I2C address 0x%02x\n", i2caddress);
739 	}
740 #endif
741 
742 	/*
743 	 * Read voltage monitor to check real voltage.
744 	 */
745 	vdd_last = read_voltage(i2caddress);
746 	if (vdd_last < 0) {
747 		printf("VID: Couldn't read sensor abort VID adjustment\n");
748 		goto exit;
749 	}
750 	printf("VID: Core voltage is at %d mV\n", vdd_last);
751 exit:
752 	i2c_multiplexer_select_vid_channel(I2C_MUX_CH_DEFAULT);
753 
754 	return ret < 0 ? -1 : 0;
755 }
756 
do_vdd_override(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])757 static int do_vdd_override(struct cmd_tbl *cmdtp,
758 			   int flag, int argc,
759 			   char *const argv[])
760 {
761 	ulong override;
762 	int ret = 0;
763 
764 	if (argc < 2)
765 		return CMD_RET_USAGE;
766 
767 	if (!strict_strtoul(argv[1], 10, &override)) {
768 		ret = adjust_vdd(override);
769 		if (ret < 0)
770 			return CMD_RET_FAILURE;
771 	} else
772 		return CMD_RET_USAGE;
773 	return 0;
774 }
775 
do_vdd_read(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])776 static int do_vdd_read(struct cmd_tbl *cmdtp, int flag, int argc,
777 		       char *const argv[])
778 {
779 	if (argc < 1)
780 		return CMD_RET_USAGE;
781 	print_vdd();
782 
783 	return 0;
784 }
785 
786 U_BOOT_CMD(
787 	vdd_override, 2, 0, do_vdd_override,
788 	"override VDD",
789 	" - override with the voltage specified in mV, eg. 1050"
790 );
791 
792 U_BOOT_CMD(
793 	vdd_read, 1, 0, do_vdd_read,
794 	"read VDD",
795 	" - Read the voltage specified in mV"
796 )
797