Add submodule dependency filesHEADmaster

Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec

1 files changed, 1291 insertions, 0 deletions

diff --git a/roms/u-boot/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c b/roms/u-boot/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c
new file mode 100644
index 000000000..35ea71a5b
--- /dev/null
+++ b/roms/u-boot/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c
@@ -0,0 +1,1291 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Freescale i.MX28 Boot PMIC init
+ *
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ */
+
+#include <common.h>
+#include <config.h>
+#include <hang.h>
+#include <log.h>
+#include <asm/io.h>
+#include <asm/arch/imx-regs.h>
+
+#include "mxs_init.h"
+
+#ifdef CONFIG_SYS_MXS_VDD5V_ONLY
+#define DCDC4P2_DROPOUT_CONFIG	POWER_DCDC4P2_DROPOUT_CTRL_100MV | \
+				POWER_DCDC4P2_DROPOUT_CTRL_SRC_4P2
+#else
+#define DCDC4P2_DROPOUT_CONFIG	POWER_DCDC4P2_DROPOUT_CTRL_100MV | \
+				POWER_DCDC4P2_DROPOUT_CTRL_SRC_SEL
+#endif
+/**
+ * mxs_power_clock2xtal() - Switch CPU core clock source to 24MHz XTAL
+ *
+ * This function switches the CPU core clock from PLL to 24MHz XTAL
+ * oscilator. This is necessary if the PLL is being reconfigured to
+ * prevent crash of the CPU core.
+ */
+static void mxs_power_clock2xtal(void)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+
+	debug("SPL: Switching CPU clock to 24MHz XTAL\n");
+
+	/* Set XTAL as CPU reference clock */
+	writel(CLKCTRL_CLKSEQ_BYPASS_CPU,
+		&clkctrl_regs->hw_clkctrl_clkseq_set);
+}
+
+/**
+ * mxs_power_clock2pll() - Switch CPU core clock source to PLL
+ *
+ * This function switches the CPU core clock from 24MHz XTAL oscilator
+ * to PLL. This can only be called once the PLL has re-locked and once
+ * the PLL is stable after reconfiguration.
+ */
+static void mxs_power_clock2pll(void)
+{
+	struct mxs_clkctrl_regs *clkctrl_regs =
+		(struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
+
+	debug("SPL: Switching CPU core clock source to PLL\n");
+
+	/*
+	 * TODO: Are we really? It looks like we turn on PLL0, but we then
+	 * set the CLKCTRL_CLKSEQ_BYPASS_CPU bit of the (which was already
+	 * set by mxs_power_clock2xtal()). Clearing this bit here seems to
+	 * introduce some instability (causing the CPU core to hang). Maybe
+	 * we aren't giving PLL0 enough time to stabilise?
+	 */
+	setbits_le32(&clkctrl_regs->hw_clkctrl_pll0ctrl0,
+			CLKCTRL_PLL0CTRL0_POWER);
+	early_delay(100);
+
+	/*
+	 * TODO: Should the PLL0 FORCE_LOCK bit be set here followed be a
+	 * wait on the PLL0 LOCK bit?
+	 */
+	setbits_le32(&clkctrl_regs->hw_clkctrl_clkseq,
+			CLKCTRL_CLKSEQ_BYPASS_CPU);
+}
+
+/**
+ * mxs_power_set_auto_restart() - Set the auto-restart bit
+ *
+ * This function ungates the RTC block and sets the AUTO_RESTART
+ * bit to work around a design bug on MX28EVK Rev. A .
+ */
+
+static void mxs_power_set_auto_restart(void)
+{
+	struct mxs_rtc_regs *rtc_regs =
+		(struct mxs_rtc_regs *)MXS_RTC_BASE;
+
+	debug("SPL: Setting auto-restart bit\n");
+
+	writel(RTC_CTRL_SFTRST, &rtc_regs->hw_rtc_ctrl_clr);
+	while (readl(&rtc_regs->hw_rtc_ctrl) & RTC_CTRL_SFTRST)
+		;
+
+	writel(RTC_CTRL_CLKGATE, &rtc_regs->hw_rtc_ctrl_clr);
+	while (readl(&rtc_regs->hw_rtc_ctrl) & RTC_CTRL_CLKGATE)
+		;
+
+	/* Do nothing if flag already set */
+	if (readl(&rtc_regs->hw_rtc_persistent0) & RTC_PERSISTENT0_AUTO_RESTART)
+		return;
+
+	while (readl(&rtc_regs->hw_rtc_stat) & RTC_STAT_NEW_REGS_MASK)
+		;
+
+	setbits_le32(&rtc_regs->hw_rtc_persistent0,
+			RTC_PERSISTENT0_AUTO_RESTART);
+	writel(RTC_CTRL_FORCE_UPDATE, &rtc_regs->hw_rtc_ctrl_set);
+	writel(RTC_CTRL_FORCE_UPDATE, &rtc_regs->hw_rtc_ctrl_clr);
+	while (readl(&rtc_regs->hw_rtc_stat) & RTC_STAT_NEW_REGS_MASK)
+		;
+	while (readl(&rtc_regs->hw_rtc_stat) & RTC_STAT_STALE_REGS_MASK)
+		;
+}
+
+/**
+ * mxs_power_set_linreg() - Set linear regulators 25mV below DC-DC converter
+ *
+ * This function configures the VDDIO, VDDA and VDDD linear regulators output
+ * to be 25mV below the VDDIO, VDDA and VDDD output from the DC-DC switching
+ * converter. This is the recommended setting for the case where we use both
+ * linear regulators and DC-DC converter to power the VDDIO rail.
+ */
+static void mxs_power_set_linreg(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	/* Set linear regulator 25mV below switching converter */
+	debug("SPL: Setting VDDD 25mV below DC-DC converters\n");
+	clrsetbits_le32(&power_regs->hw_power_vdddctrl,
+			POWER_VDDDCTRL_LINREG_OFFSET_MASK,
+			POWER_VDDDCTRL_LINREG_OFFSET_1STEPS_BELOW);
+
+	debug("SPL: Setting VDDA 25mV below DC-DC converters\n");
+	clrsetbits_le32(&power_regs->hw_power_vddactrl,
+			POWER_VDDACTRL_LINREG_OFFSET_MASK,
+			POWER_VDDACTRL_LINREG_OFFSET_1STEPS_BELOW);
+
+	debug("SPL: Setting VDDIO 25mV below DC-DC converters\n");
+	clrsetbits_le32(&power_regs->hw_power_vddioctrl,
+			POWER_VDDIOCTRL_LINREG_OFFSET_MASK,
+			POWER_VDDIOCTRL_LINREG_OFFSET_1STEPS_BELOW);
+}
+
+/**
+ * mxs_get_batt_volt() - Measure battery input voltage
+ *
+ * This function retrieves the battery input voltage and returns it.
+ */
+static int mxs_get_batt_volt(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+	uint32_t volt = readl(&power_regs->hw_power_battmonitor);
+	volt &= POWER_BATTMONITOR_BATT_VAL_MASK;
+	volt >>= POWER_BATTMONITOR_BATT_VAL_OFFSET;
+	volt *= 8;
+
+	debug("SPL: Battery Voltage = %dmV\n", volt);
+	return volt;
+}
+
+/**
+ * mxs_is_batt_ready() - Test if the battery provides enough voltage to boot
+ *
+ * This function checks if the battery input voltage is higher than 3.6V and
+ * therefore allows the system to successfully boot using this power source.
+ */
+static int mxs_is_batt_ready(void)
+{
+	return (mxs_get_batt_volt() >= 3600);
+}
+
+/**
+ * mxs_is_batt_good() - Test if battery is operational at all
+ *
+ * This function starts recharging the battery and tests if the input current
+ * provided by the 5V input recharging the battery is also sufficient to power
+ * the DC-DC converter.
+ */
+static int mxs_is_batt_good(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+	uint32_t volt = mxs_get_batt_volt();
+
+	if ((volt >= 2400) && (volt <= 4300)) {
+		debug("SPL: Battery is good\n");
+		return 1;
+	}
+
+	clrsetbits_le32(&power_regs->hw_power_5vctrl,
+		POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK,
+		0x3 << POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET);
+	writel(POWER_5VCTRL_PWD_CHARGE_4P2_MASK,
+		&power_regs->hw_power_5vctrl_clr);
+
+	clrsetbits_le32(&power_regs->hw_power_charge,
+		POWER_CHARGE_STOP_ILIMIT_MASK | POWER_CHARGE_BATTCHRG_I_MASK,
+		POWER_CHARGE_STOP_ILIMIT_10MA | 0x3);
+
+	writel(POWER_CHARGE_PWD_BATTCHRG, &power_regs->hw_power_charge_clr);
+	writel(POWER_5VCTRL_PWD_CHARGE_4P2_MASK,
+		&power_regs->hw_power_5vctrl_clr);
+
+	early_delay(500000);
+
+	volt = mxs_get_batt_volt();
+
+	if (volt >= 3500) {
+		debug("SPL: Battery Voltage too high\n");
+		return 0;
+	}
+
+	if (volt >= 2400) {
+		debug("SPL: Battery is good\n");
+		return 1;
+	}
+
+	writel(POWER_CHARGE_STOP_ILIMIT_MASK | POWER_CHARGE_BATTCHRG_I_MASK,
+		&power_regs->hw_power_charge_clr);
+	writel(POWER_CHARGE_PWD_BATTCHRG, &power_regs->hw_power_charge_set);
+
+	debug("SPL: Battery Voltage too low\n");
+	return 0;
+}
+
+/**
+ * mxs_power_setup_5v_detect() - Start the 5V input detection comparator
+ *
+ * This function enables the 5V detection comparator and sets the 5V valid
+ * threshold to 4.4V . We use 4.4V threshold here to make sure that even
+ * under high load, the voltage drop on the 5V input won't be so critical
+ * to cause undervolt on the 4P2 linear regulator supplying the DC-DC
+ * converter and thus making the system crash.
+ */
+static void mxs_power_setup_5v_detect(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	/* Start 5V detection */
+	debug("SPL: Starting 5V input detection comparator\n");
+	clrsetbits_le32(&power_regs->hw_power_5vctrl,
+			POWER_5VCTRL_VBUSVALID_TRSH_MASK,
+			POWER_5VCTRL_VBUSVALID_TRSH_4V4 |
+			POWER_5VCTRL_PWRUP_VBUS_CMPS);
+}
+
+/**
+ * mxs_power_switch_dcdc_clocksource() - Switch PLL clock for DC-DC converters
+ * @freqsel:	One of the POWER_MISC_FREQSEL_xxx defines to select the clock
+ *
+ * This function configures and then enables an alternative PLL clock source
+ * for the DC-DC converters.
+ */
+void mxs_power_switch_dcdc_clocksource(uint32_t freqsel)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	/* Select clocksource for DC-DC converters */
+	clrsetbits_le32(&power_regs->hw_power_misc,
+			POWER_MISC_FREQSEL_MASK,
+			freqsel);
+	setbits_le32(&power_regs->hw_power_misc,
+			POWER_MISC_SEL_PLLCLK);
+}
+
+/**
+ * mxs_power_setup_dcdc_clocksource() - Setup PLL clock source for DC-DC converters
+ *
+ * Normally, there is no need to switch DC-DC clocksource. This is the reason,
+ * why this function is a stub and does nothing. However, boards can implement
+ * this function when required and call mxs_power_switch_dcdc_clocksource() to
+ * switch to an alternative clock source.
+ */
+__weak void mxs_power_setup_dcdc_clocksource(void)
+{
+	debug("SPL: Using default DC-DC clocksource\n");
+}
+
+/**
+ * mxs_src_power_init() - Preconfigure the power block
+ *
+ * This function configures reasonable values for the DC-DC control loop
+ * and battery monitor.
+ */
+static void mxs_src_power_init(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Pre-Configuring power block\n");
+
+	/* Improve efficieny and reduce transient ripple */
+	writel(POWER_LOOPCTRL_TOGGLE_DIF | POWER_LOOPCTRL_EN_CM_HYST |
+		POWER_LOOPCTRL_EN_DF_HYST, &power_regs->hw_power_loopctrl_set);
+
+	clrsetbits_le32(&power_regs->hw_power_dclimits,
+			POWER_DCLIMITS_POSLIMIT_BUCK_MASK,
+			0x30 << POWER_DCLIMITS_POSLIMIT_BUCK_OFFSET);
+
+	setbits_le32(&power_regs->hw_power_battmonitor,
+			POWER_BATTMONITOR_EN_BATADJ);
+
+	/* Increase the RCSCALE level for quick DCDC response to dynamic load */
+	clrsetbits_le32(&power_regs->hw_power_loopctrl,
+			POWER_LOOPCTRL_EN_RCSCALE_MASK,
+			POWER_LOOPCTRL_RCSCALE_THRESH |
+			POWER_LOOPCTRL_EN_RCSCALE_8X);
+
+	clrsetbits_le32(&power_regs->hw_power_minpwr,
+			POWER_MINPWR_HALFFETS, POWER_MINPWR_DOUBLE_FETS);
+
+	/* 5V to battery handoff ... FIXME */
+	setbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_DCDC_XFER);
+	early_delay(30);
+	clrbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_DCDC_XFER);
+}
+
+/**
+ * mxs_power_init_4p2_params() - Configure the parameters of the 4P2 regulator
+ *
+ * This function configures the necessary parameters for the 4P2 linear
+ * regulator to supply the DC-DC converter from 5V input.
+ */
+static void mxs_power_init_4p2_params(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Configuring common 4P2 regulator params\n");
+
+	/* Setup 4P2 parameters */
+	clrsetbits_le32(&power_regs->hw_power_dcdc4p2,
+		POWER_DCDC4P2_CMPTRIP_MASK | POWER_DCDC4P2_TRG_MASK,
+		POWER_DCDC4P2_TRG_4V2 | (31 << POWER_DCDC4P2_CMPTRIP_OFFSET));
+
+	clrsetbits_le32(&power_regs->hw_power_5vctrl,
+		POWER_5VCTRL_HEADROOM_ADJ_MASK,
+		0x4 << POWER_5VCTRL_HEADROOM_ADJ_OFFSET);
+
+	clrsetbits_le32(&power_regs->hw_power_dcdc4p2,
+		POWER_DCDC4P2_DROPOUT_CTRL_MASK,
+		DCDC4P2_DROPOUT_CONFIG);
+
+	clrsetbits_le32(&power_regs->hw_power_5vctrl,
+		POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK,
+		0x3f << POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET);
+}
+
+/**
+ * mxs_enable_4p2_dcdc_input() - Enable or disable the DCDC input from 4P2
+ * @xfer:	Select if the input shall be enabled or disabled
+ *
+ * This function enables or disables the 4P2 input into the DC-DC converter.
+ */
+static void mxs_enable_4p2_dcdc_input(int xfer)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+	uint32_t tmp, vbus_thresh, vbus_5vdetect, pwd_bo;
+	uint32_t prev_5v_brnout, prev_5v_droop;
+
+	debug("SPL: %s 4P2 DC-DC Input\n", xfer ? "Enabling" : "Disabling");
+
+	if (xfer && (readl(&power_regs->hw_power_5vctrl) &
+			POWER_5VCTRL_ENABLE_DCDC)) {
+		return;
+	}
+
+	prev_5v_brnout = readl(&power_regs->hw_power_5vctrl) &
+				POWER_5VCTRL_PWDN_5VBRNOUT;
+	prev_5v_droop = readl(&power_regs->hw_power_ctrl) &
+				POWER_CTRL_ENIRQ_VDD5V_DROOP;
+
+	clrbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_PWDN_5VBRNOUT);
+	writel(POWER_RESET_UNLOCK_KEY | POWER_RESET_PWD_OFF,
+		&power_regs->hw_power_reset);
+
+	clrbits_le32(&power_regs->hw_power_ctrl, POWER_CTRL_ENIRQ_VDD5V_DROOP);
+
+	/*
+	 * Recording orignal values that will be modified temporarlily
+	 * to handle a chip bug. See chip errata for CQ ENGR00115837
+	 */
+	tmp = readl(&power_regs->hw_power_5vctrl);
+	vbus_thresh = tmp & POWER_5VCTRL_VBUSVALID_TRSH_MASK;
+	vbus_5vdetect = tmp & POWER_5VCTRL_VBUSVALID_5VDETECT;
+
+	pwd_bo = readl(&power_regs->hw_power_minpwr) & POWER_MINPWR_PWD_BO;
+
+	/*
+	 * Disable mechanisms that get erroneously tripped by when setting
+	 * the DCDC4P2 EN_DCDC
+	 */
+	clrbits_le32(&power_regs->hw_power_5vctrl,
+		POWER_5VCTRL_VBUSVALID_5VDETECT |
+		POWER_5VCTRL_VBUSVALID_TRSH_MASK);
+
+	writel(POWER_MINPWR_PWD_BO, &power_regs->hw_power_minpwr_set);
+
+	if (xfer) {
+		setbits_le32(&power_regs->hw_power_5vctrl,
+				POWER_5VCTRL_DCDC_XFER);
+		early_delay(20);
+		clrbits_le32(&power_regs->hw_power_5vctrl,
+				POWER_5VCTRL_DCDC_XFER);
+
+		setbits_le32(&power_regs->hw_power_5vctrl,
+				POWER_5VCTRL_ENABLE_DCDC);
+	} else {
+		setbits_le32(&power_regs->hw_power_dcdc4p2,
+				POWER_DCDC4P2_ENABLE_DCDC);
+	}
+
+	early_delay(25);
+
+	clrsetbits_le32(&power_regs->hw_power_5vctrl,
+			POWER_5VCTRL_VBUSVALID_TRSH_MASK, vbus_thresh);
+
+	if (vbus_5vdetect)
+		writel(vbus_5vdetect, &power_regs->hw_power_5vctrl_set);
+
+	if (!pwd_bo)
+		clrbits_le32(&power_regs->hw_power_minpwr, POWER_MINPWR_PWD_BO);
+
+	while (readl(&power_regs->hw_power_ctrl) & POWER_CTRL_VBUS_VALID_IRQ)
+		writel(POWER_CTRL_VBUS_VALID_IRQ,
+			&power_regs->hw_power_ctrl_clr);
+
+	if (prev_5v_brnout) {
+		writel(POWER_5VCTRL_PWDN_5VBRNOUT,
+			&power_regs->hw_power_5vctrl_set);
+		writel(POWER_RESET_UNLOCK_KEY,
+			&power_regs->hw_power_reset);
+	} else {
+		writel(POWER_5VCTRL_PWDN_5VBRNOUT,
+			&power_regs->hw_power_5vctrl_clr);
+		writel(POWER_RESET_UNLOCK_KEY | POWER_RESET_PWD_OFF,
+			&power_regs->hw_power_reset);
+	}
+
+	while (readl(&power_regs->hw_power_ctrl) & POWER_CTRL_VDD5V_DROOP_IRQ)
+		writel(POWER_CTRL_VDD5V_DROOP_IRQ,
+			&power_regs->hw_power_ctrl_clr);
+
+	if (prev_5v_droop)
+		clrbits_le32(&power_regs->hw_power_ctrl,
+				POWER_CTRL_ENIRQ_VDD5V_DROOP);
+	else
+		setbits_le32(&power_regs->hw_power_ctrl,
+				POWER_CTRL_ENIRQ_VDD5V_DROOP);
+}
+
+/**
+ * mxs_power_init_4p2_regulator() - Start the 4P2 regulator
+ *
+ * This function enables the 4P2 regulator and switches the DC-DC converter
+ * to use the 4P2 input.
+ */
+static void mxs_power_init_4p2_regulator(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+	uint32_t tmp, tmp2;
+
+	debug("SPL: Enabling 4P2 regulator\n");
+
+	setbits_le32(&power_regs->hw_power_dcdc4p2, POWER_DCDC4P2_ENABLE_4P2);
+
+	writel(POWER_CHARGE_ENABLE_LOAD, &power_regs->hw_power_charge_set);
+
+	writel(POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK,
+		&power_regs->hw_power_5vctrl_clr);
+	clrbits_le32(&power_regs->hw_power_dcdc4p2, POWER_DCDC4P2_TRG_MASK);
+
+	/* Power up the 4p2 rail and logic/control */
+	writel(POWER_5VCTRL_PWD_CHARGE_4P2_MASK,
+		&power_regs->hw_power_5vctrl_clr);
+
+	/*
+	 * Start charging up the 4p2 capacitor. We ramp of this charge
+	 * gradually to avoid large inrush current from the 5V cable which can
+	 * cause transients/problems
+	 */
+	debug("SPL: Charging 4P2 capacitor\n");
+	mxs_enable_4p2_dcdc_input(0);
+
+	if (readl(&power_regs->hw_power_ctrl) & POWER_CTRL_VBUS_VALID_IRQ) {
+		/*
+		 * If we arrived here, we were unable to recover from mx23 chip
+		 * errata 5837. 4P2 is disabled and sufficient battery power is
+		 * not present. Exiting to not enable DCDC power during 5V
+		 * connected state.
+		 */
+		clrbits_le32(&power_regs->hw_power_dcdc4p2,
+			POWER_DCDC4P2_ENABLE_DCDC);
+		writel(POWER_5VCTRL_PWD_CHARGE_4P2_MASK,
+			&power_regs->hw_power_5vctrl_set);
+
+		debug("SPL: Unable to recover from mx23 errata 5837\n");
+		hang();
+	}
+
+	/*
+	 * Here we set the 4p2 brownout level to something very close to 4.2V.
+	 * We then check the brownout status. If the brownout status is false,
+	 * the voltage is already close to the target voltage of 4.2V so we
+	 * can go ahead and set the 4P2 current limit to our max target limit.
+	 * If the brownout status is true, we need to ramp us the current limit
+	 * so that we don't cause large inrush current issues. We step up the
+	 * current limit until the brownout status is false or until we've
+	 * reached our maximum defined 4p2 current limit.
+	 */
+	debug("SPL: Setting 4P2 brownout level\n");
+	clrsetbits_le32(&power_regs->hw_power_dcdc4p2,
+			POWER_DCDC4P2_BO_MASK,
+			22 << POWER_DCDC4P2_BO_OFFSET);	/* 4.15V */
+
+	if (!(readl(&power_regs->hw_power_sts) & POWER_STS_DCDC_4P2_BO)) {
+		setbits_le32(&power_regs->hw_power_5vctrl,
+			0x3f << POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET);
+	} else {
+		tmp = (readl(&power_regs->hw_power_5vctrl) &
+			POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK) >>
+			POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET;
+		while (tmp < 0x3f) {
+			if (!(readl(&power_regs->hw_power_sts) &
+					POWER_STS_DCDC_4P2_BO)) {
+				tmp = readl(&power_regs->hw_power_5vctrl);
+				tmp |= POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK;
+				early_delay(100);
+				writel(tmp, &power_regs->hw_power_5vctrl);
+				break;
+			} else {
+				tmp++;
+				tmp2 = readl(&power_regs->hw_power_5vctrl);
+				tmp2 &= ~POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK;
+				tmp2 |= tmp <<
+					POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET;
+				writel(tmp2, &power_regs->hw_power_5vctrl);
+				early_delay(100);
+			}
+		}
+	}
+
+	clrbits_le32(&power_regs->hw_power_dcdc4p2, POWER_DCDC4P2_BO_MASK);
+	writel(POWER_CTRL_DCDC4P2_BO_IRQ, &power_regs->hw_power_ctrl_clr);
+}
+
+/**
+ * mxs_power_init_dcdc_4p2_source() - Switch DC-DC converter to 4P2 source
+ *
+ * This function configures the DC-DC converter to be supplied from the 4P2
+ * linear regulator.
+ */
+static void mxs_power_init_dcdc_4p2_source(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Switching DC-DC converters to 4P2\n");
+
+	if (!(readl(&power_regs->hw_power_dcdc4p2) &
+		POWER_DCDC4P2_ENABLE_DCDC)) {
+		debug("SPL: Already switched - aborting\n");
+		hang();
+	}
+
+	mxs_enable_4p2_dcdc_input(1);
+
+	if (readl(&power_regs->hw_power_ctrl) & POWER_CTRL_VBUS_VALID_IRQ) {
+		clrbits_le32(&power_regs->hw_power_dcdc4p2,
+			POWER_DCDC4P2_ENABLE_DCDC);
+		writel(POWER_5VCTRL_ENABLE_DCDC,
+			&power_regs->hw_power_5vctrl_clr);
+		writel(POWER_5VCTRL_PWD_CHARGE_4P2_MASK,
+			&power_regs->hw_power_5vctrl_set);
+	}
+}
+
+/**
+ * mxs_power_enable_4p2() - Power up the 4P2 regulator
+ *
+ * This function drives the process of powering up the 4P2 linear regulator
+ * and switching the DC-DC converter input over to the 4P2 linear regulator.
+ */
+static void mxs_power_enable_4p2(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+	uint32_t vdddctrl, vddactrl, vddioctrl;
+	uint32_t tmp;
+
+	debug("SPL: Powering up 4P2 regulator\n");
+
+	vdddctrl = readl(&power_regs->hw_power_vdddctrl);
+	vddactrl = readl(&power_regs->hw_power_vddactrl);
+	vddioctrl = readl(&power_regs->hw_power_vddioctrl);
+
+	setbits_le32(&power_regs->hw_power_vdddctrl,
+		POWER_VDDDCTRL_DISABLE_FET | POWER_VDDDCTRL_ENABLE_LINREG |
+		POWER_VDDDCTRL_PWDN_BRNOUT);
+
+	setbits_le32(&power_regs->hw_power_vddactrl,
+		POWER_VDDACTRL_DISABLE_FET | POWER_VDDACTRL_ENABLE_LINREG |
+		POWER_VDDACTRL_PWDN_BRNOUT);
+
+	setbits_le32(&power_regs->hw_power_vddioctrl,
+		POWER_VDDIOCTRL_DISABLE_FET | POWER_VDDIOCTRL_PWDN_BRNOUT);
+
+	mxs_power_init_4p2_params();
+	mxs_power_init_4p2_regulator();
+
+	/* Shutdown battery (none present) */
+	if (!mxs_is_batt_ready()) {
+		clrbits_le32(&power_regs->hw_power_dcdc4p2,
+				POWER_DCDC4P2_BO_MASK);
+		writel(POWER_CTRL_DCDC4P2_BO_IRQ,
+				&power_regs->hw_power_ctrl_clr);
+		writel(POWER_CTRL_ENIRQ_DCDC4P2_BO,
+				&power_regs->hw_power_ctrl_clr);
+	}
+
+	mxs_power_init_dcdc_4p2_source();
+
+	writel(vdddctrl, &power_regs->hw_power_vdddctrl);
+	early_delay(20);
+	writel(vddactrl, &power_regs->hw_power_vddactrl);
+	early_delay(20);
+	writel(vddioctrl, &power_regs->hw_power_vddioctrl);
+
+	/*
+	 * Check if FET is enabled on either powerout and if so,
+	 * disable load.
+	 */
+	tmp = 0;
+	tmp |= !(readl(&power_regs->hw_power_vdddctrl) &
+			POWER_VDDDCTRL_DISABLE_FET);
+	tmp |= !(readl(&power_regs->hw_power_vddactrl) &
+			POWER_VDDACTRL_DISABLE_FET);
+	tmp |= !(readl(&power_regs->hw_power_vddioctrl) &
+			POWER_VDDIOCTRL_DISABLE_FET);
+	if (tmp)
+		writel(POWER_CHARGE_ENABLE_LOAD,
+			&power_regs->hw_power_charge_clr);
+
+	debug("SPL: 4P2 regulator powered-up\n");
+}
+
+/**
+ * mxs_boot_valid_5v() - Boot from 5V supply
+ *
+ * This function configures the power block to boot from valid 5V input.
+ * This is called only if the 5V is reliable and can properly supply the
+ * CPU. This function proceeds to configure the 4P2 converter to be supplied
+ * from the 5V input.
+ */
+static void mxs_boot_valid_5v(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Booting from 5V supply\n");
+
+	/*
+	 * Use VBUSVALID level instead of VDD5V_GT_VDDIO level to trigger a 5V
+	 * disconnect event. FIXME
+	 */
+	writel(POWER_5VCTRL_VBUSVALID_5VDETECT,
+		&power_regs->hw_power_5vctrl_set);
+
+	/* Configure polarity to check for 5V disconnection. */
+	writel(POWER_CTRL_POLARITY_VBUSVALID |
+		POWER_CTRL_POLARITY_VDD5V_GT_VDDIO,
+		&power_regs->hw_power_ctrl_clr);
+
+	writel(POWER_CTRL_VBUS_VALID_IRQ | POWER_CTRL_VDD5V_GT_VDDIO_IRQ,
+		&power_regs->hw_power_ctrl_clr);
+
+	mxs_power_enable_4p2();
+}
+
+/**
+ * mxs_powerdown() - Shut down the system
+ *
+ * This function powers down the CPU completely.
+ */
+static void mxs_powerdown(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("Powering Down\n");
+
+	writel(POWER_RESET_UNLOCK_KEY, &power_regs->hw_power_reset);
+	writel(POWER_RESET_UNLOCK_KEY | POWER_RESET_PWD_OFF,
+		&power_regs->hw_power_reset);
+}
+
+/**
+ * mxs_batt_boot() - Configure the power block to boot from battery input
+ *
+ * This function configures the power block to boot from the battery voltage
+ * supply.
+ */
+static void mxs_batt_boot(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Configuring power block to boot from battery\n");
+
+	clrbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_PWDN_5VBRNOUT);
+	clrbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_ENABLE_DCDC);
+
+	clrbits_le32(&power_regs->hw_power_dcdc4p2,
+			POWER_DCDC4P2_ENABLE_DCDC | POWER_DCDC4P2_ENABLE_4P2);
+	writel(POWER_CHARGE_ENABLE_LOAD, &power_regs->hw_power_charge_clr);
+
+	/* 5V to battery handoff. */
+	setbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_DCDC_XFER);
+	early_delay(30);
+	clrbits_le32(&power_regs->hw_power_5vctrl, POWER_5VCTRL_DCDC_XFER);
+
+	writel(POWER_CTRL_ENIRQ_DCDC4P2_BO, &power_regs->hw_power_ctrl_clr);
+
+	clrsetbits_le32(&power_regs->hw_power_minpwr,
+			POWER_MINPWR_HALFFETS, POWER_MINPWR_DOUBLE_FETS);
+
+	mxs_power_set_linreg();
+
+	clrbits_le32(&power_regs->hw_power_vdddctrl,
+		POWER_VDDDCTRL_DISABLE_FET | POWER_VDDDCTRL_ENABLE_LINREG);
+
+	clrbits_le32(&power_regs->hw_power_vddactrl,
+		POWER_VDDACTRL_DISABLE_FET | POWER_VDDACTRL_ENABLE_LINREG);
+
+	clrbits_le32(&power_regs->hw_power_vddioctrl,
+		POWER_VDDIOCTRL_DISABLE_FET);
+
+	setbits_le32(&power_regs->hw_power_5vctrl,
+		POWER_5VCTRL_PWD_CHARGE_4P2_MASK);
+
+	setbits_le32(&power_regs->hw_power_5vctrl,
+		POWER_5VCTRL_ENABLE_DCDC);
+
+	clrsetbits_le32(&power_regs->hw_power_5vctrl,
+		POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK,
+		0x8 << POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET);
+
+	mxs_power_enable_4p2();
+}
+
+/**
+ * mxs_handle_5v_conflict() - Test if the 5V input is reliable
+ *
+ * This function tests if the 5V input can reliably supply the system. If it
+ * can, then proceed to configuring the system to boot from 5V source, otherwise
+ * try booting from battery supply. If we can not boot from battery supply
+ * either, shut down the system.
+ */
+static void mxs_handle_5v_conflict(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+	uint32_t tmp;
+
+	debug("SPL: Resolving 5V conflict\n");
+
+	setbits_le32(&power_regs->hw_power_vddioctrl,
+			POWER_VDDIOCTRL_BO_OFFSET_MASK);
+
+	for (;;) {
+		tmp = readl(&power_regs->hw_power_sts);
+
+		if (tmp & POWER_STS_VDDIO_BO) {
+			/*
+			 * VDDIO has a brownout, then the VDD5V_GT_VDDIO becomes
+			 * unreliable
+			 */
+			debug("SPL: VDDIO has a brownout\n");
+			mxs_powerdown();
+			break;
+		}
+
+		if (tmp & POWER_STS_VDD5V_GT_VDDIO) {
+			debug("SPL: POWER_STS_VDD5V_GT_VDDIO is set\n");
+			mxs_boot_valid_5v();
+			break;
+		} else {
+			debug("SPL: POWER_STS_VDD5V_GT_VDDIO is not set\n");
+			mxs_powerdown();
+			break;
+		}
+
+		/*
+		 * TODO: I can't see this being reached. We'll either
+		 * powerdown or boot from a stable 5V supply.
+		 */
+		if (tmp & POWER_STS_PSWITCH_MASK) {
+			debug("SPL: POWER_STS_PSWITCH_MASK is set\n");
+			mxs_batt_boot();
+			break;
+		}
+	}
+}
+
+/**
+ * mxs_5v_boot() - Configure the power block to boot from 5V input
+ *
+ * This function handles configuration of the power block when supplied by
+ * a 5V input.
+ */
+static void mxs_5v_boot(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Configuring power block to boot from 5V input\n");
+
+	/*
+	 * NOTE: In original IMX-Bootlets, this also checks for VBUSVALID,
+	 * but their implementation always returns 1 so we omit it here.
+	 */
+	if (readl(&power_regs->hw_power_sts) & POWER_STS_VDD5V_GT_VDDIO) {
+		debug("SPL: 5V VDD good\n");
+		mxs_boot_valid_5v();
+		return;
+	}
+
+	early_delay(1000);
+	if (readl(&power_regs->hw_power_sts) & POWER_STS_VDD5V_GT_VDDIO) {
+		debug("SPL: 5V VDD good (after delay)\n");
+		mxs_boot_valid_5v();
+		return;
+	}
+
+	debug("SPL: 5V VDD not good\n");
+	mxs_handle_5v_conflict();
+}
+
+/**
+ * mxs_init_batt_bo() - Configure battery brownout threshold
+ *
+ * This function configures the battery input brownout threshold. The value
+ * at which the battery brownout happens is configured to 3.0V in the code.
+ */
+static void mxs_init_batt_bo(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Initialising battery brown-out level to 3.0V\n");
+
+	/* Brownout at 3V */
+	clrsetbits_le32(&power_regs->hw_power_battmonitor,
+		POWER_BATTMONITOR_BRWNOUT_LVL_MASK,
+		15 << POWER_BATTMONITOR_BRWNOUT_LVL_OFFSET);
+
+	writel(POWER_CTRL_BATT_BO_IRQ, &power_regs->hw_power_ctrl_clr);
+	writel(POWER_CTRL_ENIRQ_BATT_BO, &power_regs->hw_power_ctrl_clr);
+}
+
+/**
+ * mxs_switch_vddd_to_dcdc_source() - Switch VDDD rail to DC-DC converter
+ *
+ * This function turns off the VDDD linear regulator and therefore makes
+ * the VDDD rail be supplied only by the DC-DC converter.
+ */
+static void mxs_switch_vddd_to_dcdc_source(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Switching VDDD to DC-DC converters\n");
+
+	clrsetbits_le32(&power_regs->hw_power_vdddctrl,
+		POWER_VDDDCTRL_LINREG_OFFSET_MASK,
+		POWER_VDDDCTRL_LINREG_OFFSET_1STEPS_BELOW);
+
+	clrbits_le32(&power_regs->hw_power_vdddctrl,
+		POWER_VDDDCTRL_DISABLE_FET | POWER_VDDDCTRL_ENABLE_LINREG |
+		POWER_VDDDCTRL_DISABLE_STEPPING);
+}
+
+/**
+ * mxs_power_configure_power_source() - Configure power block source
+ *
+ * This function is the core of the power configuration logic. The function
+ * selects the power block input source and configures the whole power block
+ * accordingly. After the configuration is complete and the system is stable
+ * again, the function switches the CPU clock source back to PLL. Finally,
+ * the function switches the voltage rails to DC-DC converter.
+ */
+static void mxs_power_configure_power_source(void)
+{
+	int batt_ready, batt_good;
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+	struct mxs_lradc_regs *lradc_regs =
+		(struct mxs_lradc_regs *)MXS_LRADC_BASE;
+
+	debug("SPL: Configuring power source\n");
+
+	mxs_power_setup_dcdc_clocksource();
+	mxs_src_power_init();
+
+	if (readl(&power_regs->hw_power_sts) & POWER_STS_VDD5V_GT_VDDIO) {
+		batt_ready = mxs_is_batt_ready();
+		if (batt_ready) {
+			/* 5V source detected, good battery detected. */
+			mxs_batt_boot();
+		} else {
+			batt_good = mxs_is_batt_good();
+			if (!batt_good) {
+				/* 5V source detected, bad battery detected. */
+				writel(LRADC_CONVERSION_AUTOMATIC,
+					&lradc_regs->hw_lradc_conversion_clr);
+				clrbits_le32(&power_regs->hw_power_battmonitor,
+					POWER_BATTMONITOR_BATT_VAL_MASK);
+			}
+			mxs_5v_boot();
+		}
+	} else {
+		/* 5V not detected, booting from battery. */
+		mxs_batt_boot();
+	}
+
+	/*
+	 * TODO: Do not switch CPU clock to PLL if we are VDD5V is sourced
+	 * from USB VBUS
+	 */
+	mxs_power_clock2pll();
+
+	mxs_init_batt_bo();
+
+	mxs_switch_vddd_to_dcdc_source();
+
+#ifdef CONFIG_MX23
+	/* Fire up the VDDMEM LinReg now that we're all set. */
+	debug("SPL: Enabling mx23 VDDMEM linear regulator\n");
+	writel(POWER_VDDMEMCTRL_ENABLE_LINREG | POWER_VDDMEMCTRL_ENABLE_ILIMIT,
+		&power_regs->hw_power_vddmemctrl);
+#endif
+}
+
+/**
+ * mxs_enable_output_rail_protection() - Enable power rail protection
+ *
+ * This function enables overload protection on the power rails. This is
+ * triggered if the power rails' voltage drops rapidly due to overload and
+ * in such case, the supply to the powerrail is cut-off, protecting the
+ * CPU from damage. Note that under such condition, the system will likely
+ * crash or misbehave.
+ */
+static void mxs_enable_output_rail_protection(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Enabling output rail protection\n");
+
+	writel(POWER_CTRL_VDDD_BO_IRQ | POWER_CTRL_VDDA_BO_IRQ |
+		POWER_CTRL_VDDIO_BO_IRQ, &power_regs->hw_power_ctrl_clr);
+
+	setbits_le32(&power_regs->hw_power_vdddctrl,
+			POWER_VDDDCTRL_PWDN_BRNOUT);
+
+	setbits_le32(&power_regs->hw_power_vddactrl,
+			POWER_VDDACTRL_PWDN_BRNOUT);
+
+	setbits_le32(&power_regs->hw_power_vddioctrl,
+			POWER_VDDIOCTRL_PWDN_BRNOUT);
+}
+
+/**
+ * mxs_get_vddio_power_source_off() - Get VDDIO rail power source
+ *
+ * This function tests if the VDDIO rail is supplied by linear regulator
+ * or by the DC-DC converter. Returns 1 if powered by linear regulator,
+ * returns 0 if powered by the DC-DC converter.
+ */
+static int mxs_get_vddio_power_source_off(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+	uint32_t tmp;
+
+	if (readl(&power_regs->hw_power_sts) & POWER_STS_VDD5V_GT_VDDIO) {
+		tmp = readl(&power_regs->hw_power_vddioctrl);
+		if (tmp & POWER_VDDIOCTRL_DISABLE_FET) {
+			if ((tmp & POWER_VDDIOCTRL_LINREG_OFFSET_MASK) ==
+				POWER_VDDIOCTRL_LINREG_OFFSET_0STEPS) {
+				return 1;
+			}
+		}
+
+		if (!(readl(&power_regs->hw_power_5vctrl) &
+			POWER_5VCTRL_ENABLE_DCDC)) {
+			if ((tmp & POWER_VDDIOCTRL_LINREG_OFFSET_MASK) ==
+				POWER_VDDIOCTRL_LINREG_OFFSET_0STEPS) {
+				return 1;
+			}
+		}
+	}
+
+	return 0;
+
+}
+
+/**
+ * mxs_get_vddd_power_source_off() - Get VDDD rail power source
+ *
+ * This function tests if the VDDD rail is supplied by linear regulator
+ * or by the DC-DC converter. Returns 1 if powered by linear regulator,
+ * returns 0 if powered by the DC-DC converter.
+ */
+static int mxs_get_vddd_power_source_off(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+	uint32_t tmp;
+
+	tmp = readl(&power_regs->hw_power_vdddctrl);
+	if (tmp & POWER_VDDDCTRL_DISABLE_FET) {
+		if ((tmp & POWER_VDDDCTRL_LINREG_OFFSET_MASK) ==
+			POWER_VDDDCTRL_LINREG_OFFSET_0STEPS) {
+			return 1;
+		}
+	}
+
+	if (readl(&power_regs->hw_power_sts) & POWER_STS_VDD5V_GT_VDDIO) {
+		if (!(readl(&power_regs->hw_power_5vctrl) &
+			POWER_5VCTRL_ENABLE_DCDC)) {
+			return 1;
+		}
+	}
+
+	if (!(tmp & POWER_VDDDCTRL_ENABLE_LINREG)) {
+		if ((tmp & POWER_VDDDCTRL_LINREG_OFFSET_MASK) ==
+			POWER_VDDDCTRL_LINREG_OFFSET_1STEPS_BELOW) {
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+struct mxs_vddx_cfg {
+	uint32_t		*reg;
+	uint8_t			step_mV;
+	uint16_t		lowest_mV;
+	int			(*powered_by_linreg)(void);
+	uint32_t		trg_mask;
+	uint32_t		bo_irq;
+	uint32_t		bo_enirq;
+	uint32_t		bo_offset_mask;
+	uint32_t		bo_offset_offset;
+};
+
+static const struct mxs_vddx_cfg mxs_vddio_cfg = {
+	.reg			= &(((struct mxs_power_regs *)MXS_POWER_BASE)->
+					hw_power_vddioctrl),
+#if defined(CONFIG_MX23)
+	.step_mV		= 25,
+#else
+	.step_mV		= 50,
+#endif
+	.lowest_mV		= 2800,
+	.powered_by_linreg	= mxs_get_vddio_power_source_off,
+	.trg_mask		= POWER_VDDIOCTRL_TRG_MASK,
+	.bo_irq			= POWER_CTRL_VDDIO_BO_IRQ,
+	.bo_enirq		= POWER_CTRL_ENIRQ_VDDIO_BO,
+	.bo_offset_mask		= POWER_VDDIOCTRL_BO_OFFSET_MASK,
+	.bo_offset_offset	= POWER_VDDIOCTRL_BO_OFFSET_OFFSET,
+};
+
+static const struct mxs_vddx_cfg mxs_vddd_cfg = {
+	.reg			= &(((struct mxs_power_regs *)MXS_POWER_BASE)->
+					hw_power_vdddctrl),
+	.step_mV		= 25,
+	.lowest_mV		= 800,
+	.powered_by_linreg	= mxs_get_vddd_power_source_off,
+	.trg_mask		= POWER_VDDDCTRL_TRG_MASK,
+	.bo_irq			= POWER_CTRL_VDDD_BO_IRQ,
+	.bo_enirq		= POWER_CTRL_ENIRQ_VDDD_BO,
+	.bo_offset_mask		= POWER_VDDDCTRL_BO_OFFSET_MASK,
+	.bo_offset_offset	= POWER_VDDDCTRL_BO_OFFSET_OFFSET,
+};
+
+#ifdef CONFIG_MX23
+static const struct mxs_vddx_cfg mxs_vddmem_cfg = {
+	.reg			= &(((struct mxs_power_regs *)MXS_POWER_BASE)->
+					hw_power_vddmemctrl),
+	.step_mV		= 50,
+	.lowest_mV		= 1700,
+	.powered_by_linreg	= NULL,
+	.trg_mask		= POWER_VDDMEMCTRL_TRG_MASK,
+	.bo_irq			= 0,
+	.bo_enirq		= 0,
+	.bo_offset_mask		= 0,
+	.bo_offset_offset	= 0,
+};
+#endif
+
+/**
+ * mxs_power_set_vddx() - Configure voltage on DC-DC converter rail
+ * @cfg:		Configuration data of the DC-DC converter rail
+ * @new_target:		New target voltage of the DC-DC converter rail
+ * @new_brownout:	New brownout trigger voltage
+ *
+ * This function configures the output voltage on the DC-DC converter rail.
+ * The rail is selected by the @cfg argument. The new voltage target is
+ * selected by the @new_target and the voltage is specified in mV. The
+ * new brownout value is selected by the @new_brownout argument and the
+ * value is also in mV.
+ */
+static void mxs_power_set_vddx(const struct mxs_vddx_cfg *cfg,
+				uint32_t new_target, uint32_t new_brownout)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+	uint32_t cur_target, diff, bo_int = 0;
+	uint32_t powered_by_linreg = 0;
+	int adjust_up, tmp;
+
+	new_brownout = DIV_ROUND_CLOSEST(new_target - new_brownout,
+					 cfg->step_mV);
+
+	cur_target = readl(cfg->reg);
+	cur_target &= cfg->trg_mask;
+	cur_target *= cfg->step_mV;
+	cur_target += cfg->lowest_mV;
+
+	adjust_up = new_target > cur_target;
+	if (cfg->powered_by_linreg)
+		powered_by_linreg = cfg->powered_by_linreg();
+
+	if (adjust_up && cfg->bo_irq) {
+		if (powered_by_linreg) {
+			bo_int = readl(cfg->reg);
+			clrbits_le32(cfg->reg, cfg->bo_enirq);
+		}
+		setbits_le32(cfg->reg, cfg->bo_offset_mask);
+	}
+
+	do {
+		if (abs(new_target - cur_target) > 100) {
+			if (adjust_up)
+				diff = cur_target + 100;
+			else
+				diff = cur_target - 100;
+		} else {
+			diff = new_target;
+		}
+
+		diff -= cfg->lowest_mV;
+		diff /= cfg->step_mV;
+
+		clrsetbits_le32(cfg->reg, cfg->trg_mask, diff);
+
+		if (powered_by_linreg ||
+			(readl(&power_regs->hw_power_sts) &
+				POWER_STS_VDD5V_GT_VDDIO))
+			early_delay(500);
+		else {
+			for (;;) {
+				tmp = readl(&power_regs->hw_power_sts);
+				if (tmp & POWER_STS_DC_OK)
+					break;
+			}
+		}
+
+		cur_target = readl(cfg->reg);
+		cur_target &= cfg->trg_mask;
+		cur_target *= cfg->step_mV;
+		cur_target += cfg->lowest_mV;
+	} while (new_target > cur_target);
+
+	if (cfg->bo_irq) {
+		if (adjust_up && powered_by_linreg) {
+			writel(cfg->bo_irq, &power_regs->hw_power_ctrl_clr);
+			if (bo_int & cfg->bo_enirq)
+				setbits_le32(cfg->reg, cfg->bo_enirq);
+		}
+
+		clrsetbits_le32(cfg->reg, cfg->bo_offset_mask,
+				new_brownout << cfg->bo_offset_offset);
+	}
+}
+
+/**
+ * mxs_setup_batt_detect() - Start the battery voltage measurement logic
+ *
+ * This function starts and configures the LRADC block. This allows the
+ * power initialization code to measure battery voltage and based on this
+ * knowledge, decide whether to boot at all, boot from battery or boot
+ * from 5V input.
+ */
+static void mxs_setup_batt_detect(void)
+{
+	debug("SPL: Starting battery voltage measurement logic\n");
+
+	mxs_lradc_init();
+	mxs_lradc_enable_batt_measurement();
+	early_delay(10);
+}
+
+/**
+ * mxs_ungate_power() - Ungate the POWER block
+ *
+ * This function ungates clock to the power block. In case the power block
+ * was still gated at this point, it will not be possible to configure the
+ * block and therefore the power initialization would fail. This function
+ * is only needed on i.MX233, on i.MX28 the power block is always ungated.
+ */
+static void mxs_ungate_power(void)
+{
+#ifdef CONFIG_MX23
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	writel(POWER_CTRL_CLKGATE, &power_regs->hw_power_ctrl_clr);
+#endif
+}
+
+/**
+ * mxs_power_init() - The power block init main function
+ *
+ * This function calls all the power block initialization functions in
+ * proper sequence to start the power block.
+ */
+void mxs_power_init(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Initialising Power Block\n");
+
+	mxs_ungate_power();
+
+	mxs_power_clock2xtal();
+	mxs_power_set_auto_restart();
+	mxs_power_set_linreg();
+	mxs_power_setup_5v_detect();
+
+	mxs_setup_batt_detect();
+
+	mxs_power_configure_power_source();
+	mxs_enable_output_rail_protection();
+
+	debug("SPL: Setting VDDIO to 3V3 (brownout @ 3v15)\n");
+	mxs_power_set_vddx(&mxs_vddio_cfg, 3300, 3150);
+
+	debug("SPL: Setting VDDD to 1V55 (brownout @ 1v400)\n");
+	mxs_power_set_vddx(&mxs_vddd_cfg, 1550, 1400);
+#ifdef CONFIG_MX23
+	debug("SPL: Setting mx23 VDDMEM to 2V5 (brownout @ 1v7)\n");
+	mxs_power_set_vddx(&mxs_vddmem_cfg, 2500, 1700);
+#endif
+	writel(POWER_CTRL_VDDD_BO_IRQ | POWER_CTRL_VDDA_BO_IRQ |
+		POWER_CTRL_VDDIO_BO_IRQ | POWER_CTRL_VDD5V_DROOP_IRQ |
+		POWER_CTRL_VBUS_VALID_IRQ | POWER_CTRL_BATT_BO_IRQ |
+		POWER_CTRL_DCDC4P2_BO_IRQ, &power_regs->hw_power_ctrl_clr);
+
+	writel(POWER_5VCTRL_PWDN_5VBRNOUT, &power_regs->hw_power_5vctrl_set);
+
+	early_delay(1000);
+}
+
+#ifdef	CONFIG_SPL_MXS_PSWITCH_WAIT
+/**
+ * mxs_power_wait_pswitch() - Wait for power switch to be pressed
+ *
+ * This function waits until the power-switch was pressed to start booting
+ * the board.
+ */
+void mxs_power_wait_pswitch(void)
+{
+	struct mxs_power_regs *power_regs =
+		(struct mxs_power_regs *)MXS_POWER_BASE;
+
+	debug("SPL: Waiting for power switch input\n");
+	while (!(readl(&power_regs->hw_power_sts) & POWER_STS_PSWITCH_MASK))
+		;
+}
+#endif