1 /*
2  * Freescale i.MX28 Boot PMIC init
3  *
4  * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
5  * on behalf of DENX Software Engineering GmbH
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <config.h>
12 #include <asm/io.h>
13 #include <asm/arch/imx-regs.h>
14 
15 #include "mxs_init.h"
16 
17 /**
18  * mxs_power_clock2xtal() - Switch CPU core clock source to 24MHz XTAL
19  *
20  * This function switches the CPU core clock from PLL to 24MHz XTAL
21  * oscilator. This is necessary if the PLL is being reconfigured to
22  * prevent crash of the CPU core.
23  */
24 static void mxs_power_clock2xtal(void)
25 {
26 	struct mxs_clkctrl_regs *clkctrl_regs =
27 		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
28 
29 	/* Set XTAL as CPU reference clock */
30 	writel(CLKCTRL_CLKSEQ_BYPASS_CPU,
31 		&clkctrl_regs->hw_clkctrl_clkseq_set);
32 }
33 
34 /**
35  * mxs_power_clock2pll() - Switch CPU core clock source to PLL
36  *
37  * This function switches the CPU core clock from 24MHz XTAL oscilator
38  * to PLL. This can only be called once the PLL has re-locked and once
39  * the PLL is stable after reconfiguration.
40  */
41 static void mxs_power_clock2pll(void)
42 {
43 	struct mxs_clkctrl_regs *clkctrl_regs =
44 		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
45 
46 	setbits_le32(&clkctrl_regs->hw_clkctrl_pll0ctrl0,
47 			CLKCTRL_PLL0CTRL0_POWER);
48 	early_delay(100);
49 	setbits_le32(&clkctrl_regs->hw_clkctrl_clkseq,
50 			CLKCTRL_CLKSEQ_BYPASS_CPU);
51 }
52 
53 /**
54  * mxs_power_set_auto_restart() - Set the auto-restart bit
55  *
56  * This function ungates the RTC block and sets the AUTO_RESTART
57  * bit to work around a design bug on MX28EVK Rev. A .
58  */
59 
60 static void mxs_power_set_auto_restart(void)
61 {
62 	struct mxs_rtc_regs *rtc_regs =
63 		(struct mxs_rtc_regs *)MXS_RTC_BASE;
64 
65 	writel(RTC_CTRL_SFTRST, &rtc_regs->hw_rtc_ctrl_clr);
66 	while (readl(&rtc_regs->hw_rtc_ctrl) & RTC_CTRL_SFTRST)
67 		;
68 
69 	writel(RTC_CTRL_CLKGATE, &rtc_regs->hw_rtc_ctrl_clr);
70 	while (readl(&rtc_regs->hw_rtc_ctrl) & RTC_CTRL_CLKGATE)
71 		;
72 
73 	/* Do nothing if flag already set */
74 	if (readl(&rtc_regs->hw_rtc_persistent0) & RTC_PERSISTENT0_AUTO_RESTART)
75 		return;
76 
77 	while (readl(&rtc_regs->hw_rtc_stat) & RTC_STAT_NEW_REGS_MASK)
78 		;
79 
80 	setbits_le32(&rtc_regs->hw_rtc_persistent0,
81 			RTC_PERSISTENT0_AUTO_RESTART);
82 	writel(RTC_CTRL_FORCE_UPDATE, &rtc_regs->hw_rtc_ctrl_set);
83 	writel(RTC_CTRL_FORCE_UPDATE, &rtc_regs->hw_rtc_ctrl_clr);
84 	while (readl(&rtc_regs->hw_rtc_stat) & RTC_STAT_NEW_REGS_MASK)
85 		;
86 	while (readl(&rtc_regs->hw_rtc_stat) & RTC_STAT_STALE_REGS_MASK)
87 		;
88 }
89 
90 /**
91  * mxs_power_set_linreg() - Set linear regulators 25mV below DC-DC converter
92  *
93  * This function configures the VDDIO, VDDA and VDDD linear regulators output
94  * to be 25mV below the VDDIO, VDDA and VDDD output from the DC-DC switching
95  * converter. This is the recommended setting for the case where we use both
96  * linear regulators and DC-DC converter to power the VDDIO rail.
97  */
98 static void mxs_power_set_linreg(void)
99 {
100 	struct mxs_power_regs *power_regs =
101 		(struct mxs_power_regs *)MXS_POWER_BASE;
102 
103 	/* Set linear regulator 25mV below switching converter */
104 	clrsetbits_le32(&power_regs->hw_power_vdddctrl,
105 			POWER_VDDDCTRL_LINREG_OFFSET_MASK,
106 			POWER_VDDDCTRL_LINREG_OFFSET_1STEPS_BELOW);
107 
108 	clrsetbits_le32(&power_regs->hw_power_vddactrl,
109 			POWER_VDDACTRL_LINREG_OFFSET_MASK,
110 			POWER_VDDACTRL_LINREG_OFFSET_1STEPS_BELOW);
111 
112 	clrsetbits_le32(&power_regs->hw_power_vddioctrl,
113 			POWER_VDDIOCTRL_LINREG_OFFSET_MASK,
114 			POWER_VDDIOCTRL_LINREG_OFFSET_1STEPS_BELOW);
115 }
116 
117 /**
118  * mxs_get_batt_volt() - Measure battery input voltage
119  *
120  * This function retrieves the battery input voltage and returns it.
121  */
122 static int mxs_get_batt_volt(void)
123 {
124 	struct mxs_power_regs *power_regs =
125 		(struct mxs_power_regs *)MXS_POWER_BASE;
126 	uint32_t volt = readl(&power_regs->hw_power_battmonitor);
127 	volt &= POWER_BATTMONITOR_BATT_VAL_MASK;
128 	volt >>= POWER_BATTMONITOR_BATT_VAL_OFFSET;
129 	volt *= 8;
130 	return volt;
131 }
132 
133 /**
134  * mxs_is_batt_ready() - Test if the battery provides enough voltage to boot
135  *
136  * This function checks if the battery input voltage is higher than 3.6V and
137  * therefore allows the system to successfully boot using this power source.
138  */
139 static int mxs_is_batt_ready(void)
140 {
141 	return (mxs_get_batt_volt() >= 3600);
142 }
143 
144 /**
145  * mxs_is_batt_good() - Test if battery is operational at all
146  *
147  * This function starts recharging the battery and tests if the input current
148  * provided by the 5V input recharging the battery is also sufficient to power
149  * the DC-DC converter.
150  */
151 static int mxs_is_batt_good(void)
152 {
153 	struct mxs_power_regs *power_regs =
154 		(struct mxs_power_regs *)MXS_POWER_BASE;
155 	uint32_t volt = mxs_get_batt_volt();
156 
157 	if ((volt >= 2400) && (volt <= 4300))
158 		return 1;
159 
160 	clrsetbits_le32(&power_regs->hw_power_5vctrl,
161 		POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK,
162 		0x3 << POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET);
163 	writel(POWER_5VCTRL_PWD_CHARGE_4P2_MASK,
164 		&power_regs->hw_power_5vctrl_clr);
165 
166 	clrsetbits_le32(&power_regs->hw_power_charge,
167 		POWER_CHARGE_STOP_ILIMIT_MASK | POWER_CHARGE_BATTCHRG_I_MASK,
168 		POWER_CHARGE_STOP_ILIMIT_10MA | 0x3);
169 
170 	writel(POWER_CHARGE_PWD_BATTCHRG, &power_regs->hw_power_charge_clr);
171 	writel(POWER_5VCTRL_PWD_CHARGE_4P2_MASK,
172 		&power_regs->hw_power_5vctrl_clr);
173 
174 	early_delay(500000);
175 
176 	volt = mxs_get_batt_volt();
177 
178 	if (volt >= 3500)
179 		return 0;
180 
181 	if (volt >= 2400)
182 		return 1;
183 
184 	writel(POWER_CHARGE_STOP_ILIMIT_MASK | POWER_CHARGE_BATTCHRG_I_MASK,
185 		&power_regs->hw_power_charge_clr);
186 	writel(POWER_CHARGE_PWD_BATTCHRG, &power_regs->hw_power_charge_set);
187 
188 	return 0;
189 }
190 
191 /**
192  * mxs_power_setup_5v_detect() - Start the 5V input detection comparator
193  *
194  * This function enables the 5V detection comparator and sets the 5V valid
195  * threshold to 4.4V . We use 4.4V threshold here to make sure that even
196  * under high load, the voltage drop on the 5V input won't be so critical
197  * to cause undervolt on the 4P2 linear regulator supplying the DC-DC
198  * converter and thus making the system crash.
199  */
200 static void mxs_power_setup_5v_detect(void)
201 {
202 	struct mxs_power_regs *power_regs =
203 		(struct mxs_power_regs *)MXS_POWER_BASE;
204 
205 	/* Start 5V detection */
206 	clrsetbits_le32(&power_regs->hw_power_5vctrl,
207 			POWER_5VCTRL_VBUSVALID_TRSH_MASK,
208 			POWER_5VCTRL_VBUSVALID_TRSH_4V4 |
209 			POWER_5VCTRL_PWRUP_VBUS_CMPS);
210 }
211 
212 /**
213  * mxs_src_power_init() - Preconfigure the power block
214  *
215  * This function configures reasonable values for the DC-DC control loop
216  * and battery monitor.
217  */
218 static void mxs_src_power_init(void)
219 {
220 	struct mxs_power_regs *power_regs =
221 		(struct mxs_power_regs *)MXS_POWER_BASE;
222 
223 	/* Improve efficieny and reduce transient ripple */
224 	writel(POWER_LOOPCTRL_TOGGLE_DIF | POWER_LOOPCTRL_EN_CM_HYST |
225 		POWER_LOOPCTRL_EN_DF_HYST, &power_regs->hw_power_loopctrl_set);
226 
227 	clrsetbits_le32(&power_regs->hw_power_dclimits,
228 			POWER_DCLIMITS_POSLIMIT_BUCK_MASK,
229 			0x30 << POWER_DCLIMITS_POSLIMIT_BUCK_OFFSET);
230 
231 	setbits_le32(&power_regs->hw_power_battmonitor,
232 			POWER_BATTMONITOR_EN_BATADJ);
233 
234 	/* Increase the RCSCALE level for quick DCDC response to dynamic load */
235 	clrsetbits_le32(&power_regs->hw_power_loopctrl,
236 			POWER_LOOPCTRL_EN_RCSCALE_MASK,
237 			POWER_LOOPCTRL_RCSCALE_THRESH |
238 			POWER_LOOPCTRL_EN_RCSCALE_8X);
239 
240 	clrsetbits_le32(&power_regs->hw_power_minpwr,
241 			POWER_MINPWR_HALFFETS, POWER_MINPWR_DOUBLE_FETS);
242 
243 	/* 5V to battery handoff ... FIXME */
244 	setbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_DCDC_XFER);
245 	early_delay(30);
246 	clrbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_DCDC_XFER);
247 }
248 
249 /**
250  * mxs_power_init_4p2_params() - Configure the parameters of the 4P2 regulator
251  *
252  * This function configures the necessary parameters for the 4P2 linear
253  * regulator to supply the DC-DC converter from 5V input.
254  */
255 static void mxs_power_init_4p2_params(void)
256 {
257 	struct mxs_power_regs *power_regs =
258 		(struct mxs_power_regs *)MXS_POWER_BASE;
259 
260 	/* Setup 4P2 parameters */
261 	clrsetbits_le32(&power_regs->hw_power_dcdc4p2,
262 		POWER_DCDC4P2_CMPTRIP_MASK | POWER_DCDC4P2_TRG_MASK,
263 		POWER_DCDC4P2_TRG_4V2 | (31 << POWER_DCDC4P2_CMPTRIP_OFFSET));
264 
265 	clrsetbits_le32(&power_regs->hw_power_5vctrl,
266 		POWER_5VCTRL_HEADROOM_ADJ_MASK,
267 		0x4 << POWER_5VCTRL_HEADROOM_ADJ_OFFSET);
268 
269 	clrsetbits_le32(&power_regs->hw_power_dcdc4p2,
270 		POWER_DCDC4P2_DROPOUT_CTRL_MASK,
271 		POWER_DCDC4P2_DROPOUT_CTRL_100MV |
272 		POWER_DCDC4P2_DROPOUT_CTRL_SRC_SEL);
273 
274 	clrsetbits_le32(&power_regs->hw_power_5vctrl,
275 		POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK,
276 		0x3f << POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET);
277 }
278 
279 /**
280  * mxs_enable_4p2_dcdc_input() - Enable or disable the DCDC input from 4P2
281  * @xfer:	Select if the input shall be enabled or disabled
282  *
283  * This function enables or disables the 4P2 input into the DC-DC converter.
284  */
285 static void mxs_enable_4p2_dcdc_input(int xfer)
286 {
287 	struct mxs_power_regs *power_regs =
288 		(struct mxs_power_regs *)MXS_POWER_BASE;
289 	uint32_t tmp, vbus_thresh, vbus_5vdetect, pwd_bo;
290 	uint32_t prev_5v_brnout, prev_5v_droop;
291 
292 	prev_5v_brnout = readl(&power_regs->hw_power_5vctrl) &
293 				POWER_5VCTRL_PWDN_5VBRNOUT;
294 	prev_5v_droop = readl(&power_regs->hw_power_ctrl) &
295 				POWER_CTRL_ENIRQ_VDD5V_DROOP;
296 
297 	clrbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_PWDN_5VBRNOUT);
298 	writel(POWER_RESET_UNLOCK_KEY | POWER_RESET_PWD_OFF,
299 		&power_regs->hw_power_reset);
300 
301 	clrbits_le32(&power_regs->hw_power_ctrl, POWER_CTRL_ENIRQ_VDD5V_DROOP);
302 
303 	if (xfer && (readl(&power_regs->hw_power_5vctrl) &
304 			POWER_5VCTRL_ENABLE_DCDC)) {
305 		return;
306 	}
307 
308 	/*
309 	 * Recording orignal values that will be modified temporarlily
310 	 * to handle a chip bug. See chip errata for CQ ENGR00115837
311 	 */
312 	tmp = readl(&power_regs->hw_power_5vctrl);
313 	vbus_thresh = tmp & POWER_5VCTRL_VBUSVALID_TRSH_MASK;
314 	vbus_5vdetect = tmp & POWER_5VCTRL_VBUSVALID_5VDETECT;
315 
316 	pwd_bo = readl(&power_regs->hw_power_minpwr) & POWER_MINPWR_PWD_BO;
317 
318 	/*
319 	 * Disable mechanisms that get erroneously tripped by when setting
320 	 * the DCDC4P2 EN_DCDC
321 	 */
322 	clrbits_le32(&power_regs->hw_power_5vctrl,
323 		POWER_5VCTRL_VBUSVALID_5VDETECT |
324 		POWER_5VCTRL_VBUSVALID_TRSH_MASK);
325 
326 	writel(POWER_MINPWR_PWD_BO, &power_regs->hw_power_minpwr_set);
327 
328 	if (xfer) {
329 		setbits_le32(&power_regs->hw_power_5vctrl,
330 				POWER_5VCTRL_DCDC_XFER);
331 		early_delay(20);
332 		clrbits_le32(&power_regs->hw_power_5vctrl,
333 				POWER_5VCTRL_DCDC_XFER);
334 
335 		setbits_le32(&power_regs->hw_power_5vctrl,
336 				POWER_5VCTRL_ENABLE_DCDC);
337 	} else {
338 		setbits_le32(&power_regs->hw_power_dcdc4p2,
339 				POWER_DCDC4P2_ENABLE_DCDC);
340 	}
341 
342 	early_delay(25);
343 
344 	clrsetbits_le32(&power_regs->hw_power_5vctrl,
345 			POWER_5VCTRL_VBUSVALID_TRSH_MASK, vbus_thresh);
346 
347 	if (vbus_5vdetect)
348 		writel(vbus_5vdetect, &power_regs->hw_power_5vctrl_set);
349 
350 	if (!pwd_bo)
351 		clrbits_le32(&power_regs->hw_power_minpwr, POWER_MINPWR_PWD_BO);
352 
353 	while (readl(&power_regs->hw_power_ctrl) & POWER_CTRL_VBUS_VALID_IRQ)
354 		writel(POWER_CTRL_VBUS_VALID_IRQ,
355 			&power_regs->hw_power_ctrl_clr);
356 
357 	if (prev_5v_brnout) {
358 		writel(POWER_5VCTRL_PWDN_5VBRNOUT,
359 			&power_regs->hw_power_5vctrl_set);
360 		writel(POWER_RESET_UNLOCK_KEY,
361 			&power_regs->hw_power_reset);
362 	} else {
363 		writel(POWER_5VCTRL_PWDN_5VBRNOUT,
364 			&power_regs->hw_power_5vctrl_clr);
365 		writel(POWER_RESET_UNLOCK_KEY | POWER_RESET_PWD_OFF,
366 			&power_regs->hw_power_reset);
367 	}
368 
369 	while (readl(&power_regs->hw_power_ctrl) & POWER_CTRL_VDD5V_DROOP_IRQ)
370 		writel(POWER_CTRL_VDD5V_DROOP_IRQ,
371 			&power_regs->hw_power_ctrl_clr);
372 
373 	if (prev_5v_droop)
374 		clrbits_le32(&power_regs->hw_power_ctrl,
375 				POWER_CTRL_ENIRQ_VDD5V_DROOP);
376 	else
377 		setbits_le32(&power_regs->hw_power_ctrl,
378 				POWER_CTRL_ENIRQ_VDD5V_DROOP);
379 }
380 
381 /**
382  * mxs_power_init_4p2_regulator() - Start the 4P2 regulator
383  *
384  * This function enables the 4P2 regulator and switches the DC-DC converter
385  * to use the 4P2 input.
386  */
387 static void mxs_power_init_4p2_regulator(void)
388 {
389 	struct mxs_power_regs *power_regs =
390 		(struct mxs_power_regs *)MXS_POWER_BASE;
391 	uint32_t tmp, tmp2;
392 
393 	setbits_le32(&power_regs->hw_power_dcdc4p2, POWER_DCDC4P2_ENABLE_4P2);
394 
395 	writel(POWER_CHARGE_ENABLE_LOAD, &power_regs->hw_power_charge_set);
396 
397 	writel(POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK,
398 		&power_regs->hw_power_5vctrl_clr);
399 	clrbits_le32(&power_regs->hw_power_dcdc4p2, POWER_DCDC4P2_TRG_MASK);
400 
401 	/* Power up the 4p2 rail and logic/control */
402 	writel(POWER_5VCTRL_PWD_CHARGE_4P2_MASK,
403 		&power_regs->hw_power_5vctrl_clr);
404 
405 	/*
406 	 * Start charging up the 4p2 capacitor. We ramp of this charge
407 	 * gradually to avoid large inrush current from the 5V cable which can
408 	 * cause transients/problems
409 	 */
410 	mxs_enable_4p2_dcdc_input(0);
411 
412 	if (readl(&power_regs->hw_power_ctrl) & POWER_CTRL_VBUS_VALID_IRQ) {
413 		/*
414 		 * If we arrived here, we were unable to recover from mx23 chip
415 		 * errata 5837. 4P2 is disabled and sufficient battery power is
416 		 * not present. Exiting to not enable DCDC power during 5V
417 		 * connected state.
418 		 */
419 		clrbits_le32(&power_regs->hw_power_dcdc4p2,
420 			POWER_DCDC4P2_ENABLE_DCDC);
421 		writel(POWER_5VCTRL_PWD_CHARGE_4P2_MASK,
422 			&power_regs->hw_power_5vctrl_set);
423 		hang();
424 	}
425 
426 	/*
427 	 * Here we set the 4p2 brownout level to something very close to 4.2V.
428 	 * We then check the brownout status. If the brownout status is false,
429 	 * the voltage is already close to the target voltage of 4.2V so we
430 	 * can go ahead and set the 4P2 current limit to our max target limit.
431 	 * If the brownout status is true, we need to ramp us the current limit
432 	 * so that we don't cause large inrush current issues. We step up the
433 	 * current limit until the brownout status is false or until we've
434 	 * reached our maximum defined 4p2 current limit.
435 	 */
436 	clrsetbits_le32(&power_regs->hw_power_dcdc4p2,
437 			POWER_DCDC4P2_BO_MASK,
438 			22 << POWER_DCDC4P2_BO_OFFSET);	/* 4.15V */
439 
440 	if (!(readl(&power_regs->hw_power_sts) & POWER_STS_DCDC_4P2_BO)) {
441 		setbits_le32(&power_regs->hw_power_5vctrl,
442 			0x3f << POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET);
443 	} else {
444 		tmp = (readl(&power_regs->hw_power_5vctrl) &
445 			POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK) >>
446 			POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET;
447 		while (tmp < 0x3f) {
448 			if (!(readl(&power_regs->hw_power_sts) &
449 					POWER_STS_DCDC_4P2_BO)) {
450 				tmp = readl(&power_regs->hw_power_5vctrl);
451 				tmp |= POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK;
452 				early_delay(100);
453 				writel(tmp, &power_regs->hw_power_5vctrl);
454 				break;
455 			} else {
456 				tmp++;
457 				tmp2 = readl(&power_regs->hw_power_5vctrl);
458 				tmp2 &= ~POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK;
459 				tmp2 |= tmp <<
460 					POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET;
461 				writel(tmp2, &power_regs->hw_power_5vctrl);
462 				early_delay(100);
463 			}
464 		}
465 	}
466 
467 	clrbits_le32(&power_regs->hw_power_dcdc4p2, POWER_DCDC4P2_BO_MASK);
468 	writel(POWER_CTRL_DCDC4P2_BO_IRQ, &power_regs->hw_power_ctrl_clr);
469 }
470 
471 /**
472  * mxs_power_init_dcdc_4p2_source() - Switch DC-DC converter to 4P2 source
473  *
474  * This function configures the DC-DC converter to be supplied from the 4P2
475  * linear regulator.
476  */
477 static void mxs_power_init_dcdc_4p2_source(void)
478 {
479 	struct mxs_power_regs *power_regs =
480 		(struct mxs_power_regs *)MXS_POWER_BASE;
481 
482 	if (!(readl(&power_regs->hw_power_dcdc4p2) &
483 		POWER_DCDC4P2_ENABLE_DCDC)) {
484 		hang();
485 	}
486 
487 	mxs_enable_4p2_dcdc_input(1);
488 
489 	if (readl(&power_regs->hw_power_ctrl) & POWER_CTRL_VBUS_VALID_IRQ) {
490 		clrbits_le32(&power_regs->hw_power_dcdc4p2,
491 			POWER_DCDC4P2_ENABLE_DCDC);
492 		writel(POWER_5VCTRL_ENABLE_DCDC,
493 			&power_regs->hw_power_5vctrl_clr);
494 		writel(POWER_5VCTRL_PWD_CHARGE_4P2_MASK,
495 			&power_regs->hw_power_5vctrl_set);
496 	}
497 }
498 
499 /**
500  * mxs_power_enable_4p2() - Power up the 4P2 regulator
501  *
502  * This function drives the process of powering up the 4P2 linear regulator
503  * and switching the DC-DC converter input over to the 4P2 linear regulator.
504  */
505 static void mxs_power_enable_4p2(void)
506 {
507 	struct mxs_power_regs *power_regs =
508 		(struct mxs_power_regs *)MXS_POWER_BASE;
509 	uint32_t vdddctrl, vddactrl, vddioctrl;
510 	uint32_t tmp;
511 
512 	vdddctrl = readl(&power_regs->hw_power_vdddctrl);
513 	vddactrl = readl(&power_regs->hw_power_vddactrl);
514 	vddioctrl = readl(&power_regs->hw_power_vddioctrl);
515 
516 	setbits_le32(&power_regs->hw_power_vdddctrl,
517 		POWER_VDDDCTRL_DISABLE_FET | POWER_VDDDCTRL_ENABLE_LINREG |
518 		POWER_VDDDCTRL_PWDN_BRNOUT);
519 
520 	setbits_le32(&power_regs->hw_power_vddactrl,
521 		POWER_VDDACTRL_DISABLE_FET | POWER_VDDACTRL_ENABLE_LINREG |
522 		POWER_VDDACTRL_PWDN_BRNOUT);
523 
524 	setbits_le32(&power_regs->hw_power_vddioctrl,
525 		POWER_VDDIOCTRL_DISABLE_FET | POWER_VDDIOCTRL_PWDN_BRNOUT);
526 
527 	mxs_power_init_4p2_params();
528 	mxs_power_init_4p2_regulator();
529 
530 	/* Shutdown battery (none present) */
531 	if (!mxs_is_batt_ready()) {
532 		clrbits_le32(&power_regs->hw_power_dcdc4p2,
533 				POWER_DCDC4P2_BO_MASK);
534 		writel(POWER_CTRL_DCDC4P2_BO_IRQ,
535 				&power_regs->hw_power_ctrl_clr);
536 		writel(POWER_CTRL_ENIRQ_DCDC4P2_BO,
537 				&power_regs->hw_power_ctrl_clr);
538 	}
539 
540 	mxs_power_init_dcdc_4p2_source();
541 
542 	writel(vdddctrl, &power_regs->hw_power_vdddctrl);
543 	early_delay(20);
544 	writel(vddactrl, &power_regs->hw_power_vddactrl);
545 	early_delay(20);
546 	writel(vddioctrl, &power_regs->hw_power_vddioctrl);
547 
548 	/*
549 	 * Check if FET is enabled on either powerout and if so,
550 	 * disable load.
551 	 */
552 	tmp = 0;
553 	tmp |= !(readl(&power_regs->hw_power_vdddctrl) &
554 			POWER_VDDDCTRL_DISABLE_FET);
555 	tmp |= !(readl(&power_regs->hw_power_vddactrl) &
556 			POWER_VDDACTRL_DISABLE_FET);
557 	tmp |= !(readl(&power_regs->hw_power_vddioctrl) &
558 			POWER_VDDIOCTRL_DISABLE_FET);
559 	if (tmp)
560 		writel(POWER_CHARGE_ENABLE_LOAD,
561 			&power_regs->hw_power_charge_clr);
562 }
563 
564 /**
565  * mxs_boot_valid_5v() - Boot from 5V supply
566  *
567  * This function configures the power block to boot from valid 5V input.
568  * This is called only if the 5V is reliable and can properly supply the
569  * CPU. This function proceeds to configure the 4P2 converter to be supplied
570  * from the 5V input.
571  */
572 static void mxs_boot_valid_5v(void)
573 {
574 	struct mxs_power_regs *power_regs =
575 		(struct mxs_power_regs *)MXS_POWER_BASE;
576 
577 	/*
578 	 * Use VBUSVALID level instead of VDD5V_GT_VDDIO level to trigger a 5V
579 	 * disconnect event. FIXME
580 	 */
581 	writel(POWER_5VCTRL_VBUSVALID_5VDETECT,
582 		&power_regs->hw_power_5vctrl_set);
583 
584 	/* Configure polarity to check for 5V disconnection. */
585 	writel(POWER_CTRL_POLARITY_VBUSVALID |
586 		POWER_CTRL_POLARITY_VDD5V_GT_VDDIO,
587 		&power_regs->hw_power_ctrl_clr);
588 
589 	writel(POWER_CTRL_VBUS_VALID_IRQ | POWER_CTRL_VDD5V_GT_VDDIO_IRQ,
590 		&power_regs->hw_power_ctrl_clr);
591 
592 	mxs_power_enable_4p2();
593 }
594 
595 /**
596  * mxs_powerdown() - Shut down the system
597  *
598  * This function powers down the CPU completely.
599  */
600 static void mxs_powerdown(void)
601 {
602 	struct mxs_power_regs *power_regs =
603 		(struct mxs_power_regs *)MXS_POWER_BASE;
604 	writel(POWER_RESET_UNLOCK_KEY, &power_regs->hw_power_reset);
605 	writel(POWER_RESET_UNLOCK_KEY | POWER_RESET_PWD_OFF,
606 		&power_regs->hw_power_reset);
607 }
608 
609 /**
610  * mxs_batt_boot() - Configure the power block to boot from battery input
611  *
612  * This function configures the power block to boot from the battery voltage
613  * supply.
614  */
615 static void mxs_batt_boot(void)
616 {
617 	struct mxs_power_regs *power_regs =
618 		(struct mxs_power_regs *)MXS_POWER_BASE;
619 
620 	clrbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_PWDN_5VBRNOUT);
621 	clrbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_ENABLE_DCDC);
622 
623 	clrbits_le32(&power_regs->hw_power_dcdc4p2,
624 			POWER_DCDC4P2_ENABLE_DCDC | POWER_DCDC4P2_ENABLE_4P2);
625 	writel(POWER_CHARGE_ENABLE_LOAD, &power_regs->hw_power_charge_clr);
626 
627 	/* 5V to battery handoff. */
628 	setbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_DCDC_XFER);
629 	early_delay(30);
630 	clrbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_DCDC_XFER);
631 
632 	writel(POWER_CTRL_ENIRQ_DCDC4P2_BO, &power_regs->hw_power_ctrl_clr);
633 
634 	clrsetbits_le32(&power_regs->hw_power_minpwr,
635 			POWER_MINPWR_HALFFETS, POWER_MINPWR_DOUBLE_FETS);
636 
637 	mxs_power_set_linreg();
638 
639 	clrbits_le32(&power_regs->hw_power_vdddctrl,
640 		POWER_VDDDCTRL_DISABLE_FET | POWER_VDDDCTRL_ENABLE_LINREG);
641 
642 	clrbits_le32(&power_regs->hw_power_vddactrl,
643 		POWER_VDDACTRL_DISABLE_FET | POWER_VDDACTRL_ENABLE_LINREG);
644 
645 	clrbits_le32(&power_regs->hw_power_vddioctrl,
646 		POWER_VDDIOCTRL_DISABLE_FET);
647 
648 	setbits_le32(&power_regs->hw_power_5vctrl,
649 		POWER_5VCTRL_PWD_CHARGE_4P2_MASK);
650 
651 	setbits_le32(&power_regs->hw_power_5vctrl,
652 		POWER_5VCTRL_ENABLE_DCDC);
653 
654 	clrsetbits_le32(&power_regs->hw_power_5vctrl,
655 		POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK,
656 		0x8 << POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET);
657 
658 	mxs_power_enable_4p2();
659 }
660 
661 /**
662  * mxs_handle_5v_conflict() - Test if the 5V input is reliable
663  *
664  * This function tests if the 5V input can reliably supply the system. If it
665  * can, then proceed to configuring the system to boot from 5V source, otherwise
666  * try booting from battery supply. If we can not boot from battery supply
667  * either, shut down the system.
668  */
669 static void mxs_handle_5v_conflict(void)
670 {
671 	struct mxs_power_regs *power_regs =
672 		(struct mxs_power_regs *)MXS_POWER_BASE;
673 	uint32_t tmp;
674 
675 	setbits_le32(&power_regs->hw_power_vddioctrl,
676 			POWER_VDDIOCTRL_BO_OFFSET_MASK);
677 
678 	for (;;) {
679 		tmp = readl(&power_regs->hw_power_sts);
680 
681 		if (tmp & POWER_STS_VDDIO_BO) {
682 			/*
683 			 * VDDIO has a brownout, then the VDD5V_GT_VDDIO becomes
684 			 * unreliable
685 			 */
686 			mxs_powerdown();
687 			break;
688 		}
689 
690 		if (tmp & POWER_STS_VDD5V_GT_VDDIO) {
691 			mxs_boot_valid_5v();
692 			break;
693 		} else {
694 			mxs_powerdown();
695 			break;
696 		}
697 
698 		if (tmp & POWER_STS_PSWITCH_MASK) {
699 			mxs_batt_boot();
700 			break;
701 		}
702 	}
703 }
704 
705 /**
706  * mxs_5v_boot() - Configure the power block to boot from 5V input
707  *
708  * This function handles configuration of the power block when supplied by
709  * a 5V input.
710  */
711 static void mxs_5v_boot(void)
712 {
713 	struct mxs_power_regs *power_regs =
714 		(struct mxs_power_regs *)MXS_POWER_BASE;
715 
716 	/*
717 	 * NOTE: In original IMX-Bootlets, this also checks for VBUSVALID,
718 	 * but their implementation always returns 1 so we omit it here.
719 	 */
720 	if (readl(&power_regs->hw_power_sts) & POWER_STS_VDD5V_GT_VDDIO) {
721 		mxs_boot_valid_5v();
722 		return;
723 	}
724 
725 	early_delay(1000);
726 	if (readl(&power_regs->hw_power_sts) & POWER_STS_VDD5V_GT_VDDIO) {
727 		mxs_boot_valid_5v();
728 		return;
729 	}
730 
731 	mxs_handle_5v_conflict();
732 }
733 
734 /**
735  * mxs_init_batt_bo() - Configure battery brownout threshold
736  *
737  * This function configures the battery input brownout threshold. The value
738  * at which the battery brownout happens is configured to 3.0V in the code.
739  */
740 static void mxs_init_batt_bo(void)
741 {
742 	struct mxs_power_regs *power_regs =
743 		(struct mxs_power_regs *)MXS_POWER_BASE;
744 
745 	/* Brownout at 3V */
746 	clrsetbits_le32(&power_regs->hw_power_battmonitor,
747 		POWER_BATTMONITOR_BRWNOUT_LVL_MASK,
748 		15 << POWER_BATTMONITOR_BRWNOUT_LVL_OFFSET);
749 
750 	writel(POWER_CTRL_BATT_BO_IRQ, &power_regs->hw_power_ctrl_clr);
751 	writel(POWER_CTRL_ENIRQ_BATT_BO, &power_regs->hw_power_ctrl_clr);
752 }
753 
754 /**
755  * mxs_switch_vddd_to_dcdc_source() - Switch VDDD rail to DC-DC converter
756  *
757  * This function turns off the VDDD linear regulator and therefore makes
758  * the VDDD rail be supplied only by the DC-DC converter.
759  */
760 static void mxs_switch_vddd_to_dcdc_source(void)
761 {
762 	struct mxs_power_regs *power_regs =
763 		(struct mxs_power_regs *)MXS_POWER_BASE;
764 
765 	clrsetbits_le32(&power_regs->hw_power_vdddctrl,
766 		POWER_VDDDCTRL_LINREG_OFFSET_MASK,
767 		POWER_VDDDCTRL_LINREG_OFFSET_1STEPS_BELOW);
768 
769 	clrbits_le32(&power_regs->hw_power_vdddctrl,
770 		POWER_VDDDCTRL_DISABLE_FET | POWER_VDDDCTRL_ENABLE_LINREG |
771 		POWER_VDDDCTRL_DISABLE_STEPPING);
772 }
773 
774 /**
775  * mxs_power_configure_power_source() - Configure power block source
776  *
777  * This function is the core of the power configuration logic. The function
778  * selects the power block input source and configures the whole power block
779  * accordingly. After the configuration is complete and the system is stable
780  * again, the function switches the CPU clock source back to PLL. Finally,
781  * the function switches the voltage rails to DC-DC converter.
782  */
783 static void mxs_power_configure_power_source(void)
784 {
785 	int batt_ready, batt_good;
786 	struct mxs_power_regs *power_regs =
787 		(struct mxs_power_regs *)MXS_POWER_BASE;
788 	struct mxs_lradc_regs *lradc_regs =
789 		(struct mxs_lradc_regs *)MXS_LRADC_BASE;
790 
791 	mxs_src_power_init();
792 
793 	if (readl(&power_regs->hw_power_sts) & POWER_STS_VDD5V_GT_VDDIO) {
794 		batt_ready = mxs_is_batt_ready();
795 		if (batt_ready) {
796 			/* 5V source detected, good battery detected. */
797 			mxs_batt_boot();
798 		} else {
799 			batt_good = mxs_is_batt_good();
800 			if (!batt_good) {
801 				/* 5V source detected, bad battery detected. */
802 				writel(LRADC_CONVERSION_AUTOMATIC,
803 					&lradc_regs->hw_lradc_conversion_clr);
804 				clrbits_le32(&power_regs->hw_power_battmonitor,
805 					POWER_BATTMONITOR_BATT_VAL_MASK);
806 			}
807 			mxs_5v_boot();
808 		}
809 	} else {
810 		/* 5V not detected, booting from battery. */
811 		mxs_batt_boot();
812 	}
813 
814 	mxs_power_clock2pll();
815 
816 	mxs_init_batt_bo();
817 
818 	mxs_switch_vddd_to_dcdc_source();
819 
820 #ifdef CONFIG_MX23
821 	/* Fire up the VDDMEM LinReg now that we're all set. */
822 	writel(POWER_VDDMEMCTRL_ENABLE_LINREG | POWER_VDDMEMCTRL_ENABLE_ILIMIT,
823 		&power_regs->hw_power_vddmemctrl);
824 #endif
825 }
826 
827 /**
828  * mxs_enable_output_rail_protection() - Enable power rail protection
829  *
830  * This function enables overload protection on the power rails. This is
831  * triggered if the power rails' voltage drops rapidly due to overload and
832  * in such case, the supply to the powerrail is cut-off, protecting the
833  * CPU from damage. Note that under such condition, the system will likely
834  * crash or misbehave.
835  */
836 static void mxs_enable_output_rail_protection(void)
837 {
838 	struct mxs_power_regs *power_regs =
839 		(struct mxs_power_regs *)MXS_POWER_BASE;
840 
841 	writel(POWER_CTRL_VDDD_BO_IRQ | POWER_CTRL_VDDA_BO_IRQ |
842 		POWER_CTRL_VDDIO_BO_IRQ, &power_regs->hw_power_ctrl_clr);
843 
844 	setbits_le32(&power_regs->hw_power_vdddctrl,
845 			POWER_VDDDCTRL_PWDN_BRNOUT);
846 
847 	setbits_le32(&power_regs->hw_power_vddactrl,
848 			POWER_VDDACTRL_PWDN_BRNOUT);
849 
850 	setbits_le32(&power_regs->hw_power_vddioctrl,
851 			POWER_VDDIOCTRL_PWDN_BRNOUT);
852 }
853 
854 /**
855  * mxs_get_vddio_power_source_off() - Get VDDIO rail power source
856  *
857  * This function tests if the VDDIO rail is supplied by linear regulator
858  * or by the DC-DC converter. Returns 1 if powered by linear regulator,
859  * returns 0 if powered by the DC-DC converter.
860  */
861 static int mxs_get_vddio_power_source_off(void)
862 {
863 	struct mxs_power_regs *power_regs =
864 		(struct mxs_power_regs *)MXS_POWER_BASE;
865 	uint32_t tmp;
866 
867 	if (readl(&power_regs->hw_power_sts) & POWER_STS_VDD5V_GT_VDDIO) {
868 		tmp = readl(&power_regs->hw_power_vddioctrl);
869 		if (tmp & POWER_VDDIOCTRL_DISABLE_FET) {
870 			if ((tmp & POWER_VDDIOCTRL_LINREG_OFFSET_MASK) ==
871 				POWER_VDDIOCTRL_LINREG_OFFSET_0STEPS) {
872 				return 1;
873 			}
874 		}
875 
876 		if (!(readl(&power_regs->hw_power_5vctrl) &
877 			POWER_5VCTRL_ENABLE_DCDC)) {
878 			if ((tmp & POWER_VDDIOCTRL_LINREG_OFFSET_MASK) ==
879 				POWER_VDDIOCTRL_LINREG_OFFSET_0STEPS) {
880 				return 1;
881 			}
882 		}
883 	}
884 
885 	return 0;
886 
887 }
888 
889 /**
890  * mxs_get_vddd_power_source_off() - Get VDDD rail power source
891  *
892  * This function tests if the VDDD rail is supplied by linear regulator
893  * or by the DC-DC converter. Returns 1 if powered by linear regulator,
894  * returns 0 if powered by the DC-DC converter.
895  */
896 static int mxs_get_vddd_power_source_off(void)
897 {
898 	struct mxs_power_regs *power_regs =
899 		(struct mxs_power_regs *)MXS_POWER_BASE;
900 	uint32_t tmp;
901 
902 	tmp = readl(&power_regs->hw_power_vdddctrl);
903 	if (tmp & POWER_VDDDCTRL_DISABLE_FET) {
904 		if ((tmp & POWER_VDDDCTRL_LINREG_OFFSET_MASK) ==
905 			POWER_VDDDCTRL_LINREG_OFFSET_0STEPS) {
906 			return 1;
907 		}
908 	}
909 
910 	if (readl(&power_regs->hw_power_sts) & POWER_STS_VDD5V_GT_VDDIO) {
911 		if (!(readl(&power_regs->hw_power_5vctrl) &
912 			POWER_5VCTRL_ENABLE_DCDC)) {
913 			return 1;
914 		}
915 	}
916 
917 	if (!(tmp & POWER_VDDDCTRL_ENABLE_LINREG)) {
918 		if ((tmp & POWER_VDDDCTRL_LINREG_OFFSET_MASK) ==
919 			POWER_VDDDCTRL_LINREG_OFFSET_1STEPS_BELOW) {
920 			return 1;
921 		}
922 	}
923 
924 	return 0;
925 }
926 
927 struct mxs_vddx_cfg {
928 	uint32_t		*reg;
929 	uint8_t			step_mV;
930 	uint16_t		lowest_mV;
931 	int			(*powered_by_linreg)(void);
932 	uint32_t		trg_mask;
933 	uint32_t		bo_irq;
934 	uint32_t		bo_enirq;
935 	uint32_t		bo_offset_mask;
936 	uint32_t		bo_offset_offset;
937 };
938 
939 static const struct mxs_vddx_cfg mxs_vddio_cfg = {
940 	.reg			= &(((struct mxs_power_regs *)MXS_POWER_BASE)->
941 					hw_power_vddioctrl),
942 #if defined(CONFIG_MX23)
943 	.step_mV		= 25,
944 #else
945 	.step_mV		= 50,
946 #endif
947 	.lowest_mV		= 2800,
948 	.powered_by_linreg	= mxs_get_vddio_power_source_off,
949 	.trg_mask		= POWER_VDDIOCTRL_TRG_MASK,
950 	.bo_irq			= POWER_CTRL_VDDIO_BO_IRQ,
951 	.bo_enirq		= POWER_CTRL_ENIRQ_VDDIO_BO,
952 	.bo_offset_mask		= POWER_VDDIOCTRL_BO_OFFSET_MASK,
953 	.bo_offset_offset	= POWER_VDDIOCTRL_BO_OFFSET_OFFSET,
954 };
955 
956 static const struct mxs_vddx_cfg mxs_vddd_cfg = {
957 	.reg			= &(((struct mxs_power_regs *)MXS_POWER_BASE)->
958 					hw_power_vdddctrl),
959 	.step_mV		= 25,
960 	.lowest_mV		= 800,
961 	.powered_by_linreg	= mxs_get_vddd_power_source_off,
962 	.trg_mask		= POWER_VDDDCTRL_TRG_MASK,
963 	.bo_irq			= POWER_CTRL_VDDD_BO_IRQ,
964 	.bo_enirq		= POWER_CTRL_ENIRQ_VDDD_BO,
965 	.bo_offset_mask		= POWER_VDDDCTRL_BO_OFFSET_MASK,
966 	.bo_offset_offset	= POWER_VDDDCTRL_BO_OFFSET_OFFSET,
967 };
968 
969 #ifdef CONFIG_MX23
970 static const struct mxs_vddx_cfg mxs_vddmem_cfg = {
971 	.reg			= &(((struct mxs_power_regs *)MXS_POWER_BASE)->
972 					hw_power_vddmemctrl),
973 	.step_mV		= 50,
974 	.lowest_mV		= 1700,
975 	.powered_by_linreg	= NULL,
976 	.trg_mask		= POWER_VDDMEMCTRL_TRG_MASK,
977 	.bo_irq			= 0,
978 	.bo_enirq		= 0,
979 	.bo_offset_mask		= 0,
980 	.bo_offset_offset	= 0,
981 };
982 #endif
983 
984 /**
985  * mxs_power_set_vddx() - Configure voltage on DC-DC converter rail
986  * @cfg:		Configuration data of the DC-DC converter rail
987  * @new_target:		New target voltage of the DC-DC converter rail
988  * @new_brownout:	New brownout trigger voltage
989  *
990  * This function configures the output voltage on the DC-DC converter rail.
991  * The rail is selected by the @cfg argument. The new voltage target is
992  * selected by the @new_target and the voltage is specified in mV. The
993  * new brownout value is selected by the @new_brownout argument and the
994  * value is also in mV.
995  */
996 static void mxs_power_set_vddx(const struct mxs_vddx_cfg *cfg,
997 				uint32_t new_target, uint32_t new_brownout)
998 {
999 	struct mxs_power_regs *power_regs =
1000 		(struct mxs_power_regs *)MXS_POWER_BASE;
1001 	uint32_t cur_target, diff, bo_int = 0;
1002 	uint32_t powered_by_linreg = 0;
1003 	int adjust_up, tmp;
1004 
1005 	new_brownout = DIV_ROUND(new_target - new_brownout, cfg->step_mV);
1006 
1007 	cur_target = readl(cfg->reg);
1008 	cur_target &= cfg->trg_mask;
1009 	cur_target *= cfg->step_mV;
1010 	cur_target += cfg->lowest_mV;
1011 
1012 	adjust_up = new_target > cur_target;
1013 	if (cfg->powered_by_linreg)
1014 		powered_by_linreg = cfg->powered_by_linreg();
1015 
1016 	if (adjust_up && cfg->bo_irq) {
1017 		if (powered_by_linreg) {
1018 			bo_int = readl(cfg->reg);
1019 			clrbits_le32(cfg->reg, cfg->bo_enirq);
1020 		}
1021 		setbits_le32(cfg->reg, cfg->bo_offset_mask);
1022 	}
1023 
1024 	do {
1025 		if (abs(new_target - cur_target) > 100) {
1026 			if (adjust_up)
1027 				diff = cur_target + 100;
1028 			else
1029 				diff = cur_target - 100;
1030 		} else {
1031 			diff = new_target;
1032 		}
1033 
1034 		diff -= cfg->lowest_mV;
1035 		diff /= cfg->step_mV;
1036 
1037 		clrsetbits_le32(cfg->reg, cfg->trg_mask, diff);
1038 
1039 		if (powered_by_linreg ||
1040 			(readl(&power_regs->hw_power_sts) &
1041 				POWER_STS_VDD5V_GT_VDDIO))
1042 			early_delay(500);
1043 		else {
1044 			for (;;) {
1045 				tmp = readl(&power_regs->hw_power_sts);
1046 				if (tmp & POWER_STS_DC_OK)
1047 					break;
1048 			}
1049 		}
1050 
1051 		cur_target = readl(cfg->reg);
1052 		cur_target &= cfg->trg_mask;
1053 		cur_target *= cfg->step_mV;
1054 		cur_target += cfg->lowest_mV;
1055 	} while (new_target > cur_target);
1056 
1057 	if (cfg->bo_irq) {
1058 		if (adjust_up && powered_by_linreg) {
1059 			writel(cfg->bo_irq, &power_regs->hw_power_ctrl_clr);
1060 			if (bo_int & cfg->bo_enirq)
1061 				setbits_le32(cfg->reg, cfg->bo_enirq);
1062 		}
1063 
1064 		clrsetbits_le32(cfg->reg, cfg->bo_offset_mask,
1065 				new_brownout << cfg->bo_offset_offset);
1066 	}
1067 }
1068 
1069 /**
1070  * mxs_setup_batt_detect() - Start the battery voltage measurement logic
1071  *
1072  * This function starts and configures the LRADC block. This allows the
1073  * power initialization code to measure battery voltage and based on this
1074  * knowledge, decide whether to boot at all, boot from battery or boot
1075  * from 5V input.
1076  */
1077 static void mxs_setup_batt_detect(void)
1078 {
1079 	mxs_lradc_init();
1080 	mxs_lradc_enable_batt_measurement();
1081 	early_delay(10);
1082 }
1083 
1084 /**
1085  * mxs_ungate_power() - Ungate the POWER block
1086  *
1087  * This function ungates clock to the power block. In case the power block
1088  * was still gated at this point, it will not be possible to configure the
1089  * block and therefore the power initialization would fail. This function
1090  * is only needed on i.MX233, on i.MX28 the power block is always ungated.
1091  */
1092 static void mxs_ungate_power(void)
1093 {
1094 #ifdef CONFIG_MX23
1095 	struct mxs_power_regs *power_regs =
1096 		(struct mxs_power_regs *)MXS_POWER_BASE;
1097 
1098 	writel(POWER_CTRL_CLKGATE, &power_regs->hw_power_ctrl_clr);
1099 #endif
1100 }
1101 
1102 /**
1103  * mxs_power_init() - The power block init main function
1104  *
1105  * This function calls all the power block initialization functions in
1106  * proper sequence to start the power block.
1107  */
1108 void mxs_power_init(void)
1109 {
1110 	struct mxs_power_regs *power_regs =
1111 		(struct mxs_power_regs *)MXS_POWER_BASE;
1112 
1113 	mxs_ungate_power();
1114 
1115 	mxs_power_clock2xtal();
1116 	mxs_power_set_auto_restart();
1117 	mxs_power_set_linreg();
1118 	mxs_power_setup_5v_detect();
1119 
1120 	mxs_setup_batt_detect();
1121 
1122 	mxs_power_configure_power_source();
1123 	mxs_enable_output_rail_protection();
1124 
1125 	mxs_power_set_vddx(&mxs_vddio_cfg, 3300, 3150);
1126 	mxs_power_set_vddx(&mxs_vddd_cfg, 1500, 1000);
1127 #ifdef CONFIG_MX23
1128 	mxs_power_set_vddx(&mxs_vddmem_cfg, 2500, 1700);
1129 #endif
1130 	writel(POWER_CTRL_VDDD_BO_IRQ | POWER_CTRL_VDDA_BO_IRQ |
1131 		POWER_CTRL_VDDIO_BO_IRQ | POWER_CTRL_VDD5V_DROOP_IRQ |
1132 		POWER_CTRL_VBUS_VALID_IRQ | POWER_CTRL_BATT_BO_IRQ |
1133 		POWER_CTRL_DCDC4P2_BO_IRQ, &power_regs->hw_power_ctrl_clr);
1134 
1135 	writel(POWER_5VCTRL_PWDN_5VBRNOUT, &power_regs->hw_power_5vctrl_set);
1136 
1137 	early_delay(1000);
1138 }
1139 
1140 #ifdef	CONFIG_SPL_MXS_PSWITCH_WAIT
1141 /**
1142  * mxs_power_wait_pswitch() - Wait for power switch to be pressed
1143  *
1144  * This function waits until the power-switch was pressed to start booting
1145  * the board.
1146  */
1147 void mxs_power_wait_pswitch(void)
1148 {
1149 	struct mxs_power_regs *power_regs =
1150 		(struct mxs_power_regs *)MXS_POWER_BASE;
1151 
1152 	while (!(readl(&power_regs->hw_power_sts) & POWER_STS_PSWITCH_MASK))
1153 		;
1154 }
1155 #endif
1156