u-boot/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c
Graeme Russ 7a08603707 arm: mxs: Enable booting of mx28 without battery
Section 4.1.2 of Freescale Application Note AN4199 describes the
configuration required to operate the mx28 from a 5V source without a
battery.

This patch changes the behaviour of the dropout control of the DC-DC
converter (refer to section 11.12.9 of the mx28 Application Processor
Reference Manual - Document Number: MCIMX28RM, Rev 2, 08/2013) to the
following:
 - Always use 4P2 Linear Regulator if CONFIG_SYS_MXS_VDD5V_ONLY is defined
 - Switch between 4P2 Linear Regulator and Battery, using whichever has
   the highest voltage if CONFIG_SYS_MXS_VDD5V_ONLY isnot set (this is
   the same as the pre-patch behaviour)

Signed-off-by: Graeme Russ <gruss@tss-engineering.com>
Signed-off-by: Damien Gotfroi <dgotfroi@greenwatch.be>
2015-02-10 12:48:50 +01:00

1256 lines
36 KiB
C

/*
* Freescale i.MX28 Boot PMIC init
*
* Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
* on behalf of DENX Software Engineering GmbH
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <config.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_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");
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);
if (xfer && (readl(&power_regs->hw_power_5vctrl) &
POWER_5VCTRL_ENABLE_DCDC)) {
return;
}
/*
* 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_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 1V5 (brownout @ 1v0)\n");
mxs_power_set_vddx(&mxs_vddd_cfg, 1500, 1000);
#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