Linux/AM3351: PMIC sleep mode in SPL

void am33xx_spl_board_init(void)
{
        int mpu_vdd;
        unsigned long status, reg;
        struct davinci_rtc *rtc = (struct davinci_rtc *)RTC_BASE;
        struct rtc_time tm;
        unsigned long time;
        char index=0;
        /* BeagleBone PMIC Code */
        int usb_cur_lim;


        if (i2c_probe(TPS65217_CHIP_PM))
                return;

        /*
         * AM3351 supports 300MHz.
         */
        dpll_mpu_opp100.m = MPUPLL_M_300;

        /*
         * Increase USB current limit to 1300mA and set
         * the MPU(Same as VDD CORE in AM3351) voltage
         * controller as needed.
         */

        /* Set UVLO to 2.89V */
        if (tps65217_reg_write(TPS65217_PROT_LEVEL_1,
                               TPS65217_DEFUVLO,
                               TPS65217_DEFUVLO_2_89,
                               TPS65217_DEFUVLO_MASK))
                puts("tps65217_reg_write failure\n");

        usb_cur_lim = TPS65217_USB_INPUT_CUR_LIMIT_1300MA;
        mpu_vdd = TPS65217_DCDC_VOLT_SEL_1125MV;

        if (tps65217_reg_write(TPS65217_PROT_LEVEL_NONE,
                               TPS65217_POWER_PATH,
                               usb_cur_lim,
                               TPS65217_USB_INPUT_CUR_LIMIT_MASK))
                puts("tps65217_reg_write failure\n");

        /* Set DCDC3 (CORE) voltage to 1.125V */
        if (tps65217_voltage_update(TPS65217_DEFDCDC3,
                                    TPS65217_DCDC_VOLT_SEL_1800MV)) {
                puts("tps65217_voltage_update failure\n");
                return;
        }

        /* Set CORE Frequencies to OPP100 */
        do_setup_dpll(&dpll_core_regs, &dpll_core_opp100);

        /* Set DCDC2 (MPU) voltage */
        if (tps65217_voltage_update(TPS65217_DEFDCDC2, mpu_vdd)) {
                puts("tps65217_voltage_update failure\n");
                return;
        }

        /* Set LDO2 to 2.75V */
        if (tps65217_reg_write(TPS65217_PROT_LEVEL_2,
                               TPS65217_DEFLDO2,
                               TPS65217_LDO2_VOLTAGE_OUT_2_85,
                               TPS65217_LDO2_MASK))
                puts("tps65217_reg_write failure\n");
        /*
         * Set LDO3 to 1.8V and LDO4 to 3.3V
         */
        if (tps65217_reg_write(TPS65217_PROT_LEVEL_2,
                               TPS65217_DEFLS1,
                               TPS65217_LDO_VOLTAGE_OUT_1_8,
                               TPS65217_LDO_MASK))
                puts("tps65217_reg_write failure\n");

        if (tps65217_reg_write(TPS65217_PROT_LEVEL_2,
                               TPS65217_DEFLS2,
                               TPS65217_LDO_VOLTAGE_OUT_2_85,
                               TPS65217_LDO_MASK))
                puts("tps65217_reg_write failure\n");

        /* Set PMIC sleep during shutdown in Status Register */
        tps65217_reg_write(TPS65217_PROT_LEVEL_NONE,
                                TPS65217_STATUS, ~TPS65217_PWR_OFF, 0xFF);

        tps65217_reg_write(TPS65217_PROT_LEVEL_NONE,
                                TPS65217_CHGCONFIG1, 0x30, 0xFF);

        /* charge voltage selection 4.25V */
        tps65217_reg_write(TPS65217_PROT_LEVEL_NONE,
                                TPS65217_CHGCONFIG2, 0xB0, 0xFF);

        /* Termination current factor 2.5 % */
        tps65217_reg_write(TPS65217_PROT_LEVEL_NONE,
                                TPS65217_CHGCONFIG3, 0x30, 0xFF);
        /* charger enabled */
        tps65217_reg_write(TPS65217_PROT_LEVEL_NONE,
                                TPS65217_CHGCONFIG1, 0x31, 0xFF);

        /* Set MPU Frequency to what we detected now that voltages are set */
        do_setup_dpll(&dpll_mpu_regs, &dpll_mpu_opp100);
        /* Check RTC is running */
        if ((status & RTC_STATE_RUN) != RTC_STATE_RUN) {
                puts("RTC doesn't run. Restart RTC \n");

                /* run RTC counter */
                writel(0x01, RTC_BASE + 0x40);
                mdelay(10);

                status = readl(&rtc->status);
                /* Check again RTC running or not */
                if ((status & RTC_STATE_RUN) != RTC_STATE_RUN)
                        puts("RTC doesn't run after restart \n");
                printf("RTC: Status reg: 0x%02x ctrl reg: 0x%02x\r\n",readl(&rtc->status), readl(&rtc->ctrl));
        }

        puts("Preparing pmic sleep mode \n");
        /* Clear previous ALARM2 interuppt */
        writel(0x80, RTC_BASE + 0x44);
        /* Read Current RTC time */
        rtc_get_time(&tm);
        /* Convert Gregorian date to seconds since 01-01-1970 00:00:00 */
        time =  rtc_maketime(&tm);
        /* Convert seconds since 01-01-1970 00:00:00 to Gregorian date */
        if((readl(AM33XX_GPIO0_BASE + 0x138) & 0x00001000))
                rtc_to_time(time + 1, &tm);
        else
                rtc_to_time(time + 2 , &tm);
        writel(0x04400000, AM33XX_GPIO0_BASE + 0x13C);

        rtc_wait_not_busy();
        /* Set alarm 2 event */
        rtc_set_alarm(&tm);

        if(!(readl(AM33XX_GPIO0_BASE + 0x138) & 0x00001000)){
                do{
                        mdelay(100);
                        index ++;
                        /* Check keys are pressed continuously for 3 seconds */                                                                                                         if(index == 10)
                        break;
                }while(!(readl(AM33XX_GPIO0_BASE + 0x138) & 0x00001000));
        }
        if(index != 10){
                puts("PMIC will go to sleep in 1 second\r\n");
                writel(0x00C00000, AM33XX_GPIO0_BASE + 0x13C);

                while(1){
                        mdelay(100);
                        rtc_get_time(&tm);
                }
                /* Wait in loop until pmic goes to sleep */
                while(1);
        }
        puts("Booting........\r\n");

        writel(0, RTC_BASE + 0x48);
        writel(0xFB3FFFFF, AM33XX_GPIO0_BASE + 0x134);
        writel(0, AM33XX_GPIO0_BASE + 0x13C);
}


void rtc_wait_not_busy(void)
{
        struct davinci_rtc *rtc = (struct davinci_rtc *)RTC_BASE;
        unsigned long status;
        char count;

        for (count = 0; count < 50; count++) {
                status = readl(&rtc->status);
                if (!(status & RTC_STATE_BUSY))
                        break;
                udelay(1);
        }
}

static int rtc_get_time(struct rtc_time *tmp)
{
        struct davinci_rtc *rtc = (struct davinci_rtc *)RTC_BASE;
        unsigned long sec, min, hour, mday, wday, mon_cent, year;
        unsigned long status;

        printf("RTC Status reg: 0x%02x ctrl reg: 0x%02x\r\n",readl(&rtc->status), readl(&rtc->ctrl));
        status = readl(&rtc->status);
        if ((status & RTC_STATE_RUN) != RTC_STATE_RUN) {
                                puts("RTC doesn't run \n");
                                                        return -1;
                                                                                }
        if ((status & RTC_STATE_BUSY) == RTC_STATE_BUSY)
                                udelay(20);

        writel(OMAP_RTC_STATUS_ALARM2, RTC_BASE + 0x44);
        udelay(35);

        sec     = readl(&rtc->second);
        min     = readl(&rtc->minutes);
        hour    = readl(&rtc->hours);
        mday    = readl(&rtc->day);
        wday    = readl(&rtc->dotw);
        mon_cent = readl(&rtc->month);
        year    = readl(&rtc->year);

        printf("Get RTC year: %02lx mon/cent: %02lx mday: %02lx wday: %02lx "
                        "hr: %02lx min: %02lx sec: %02lx\n",
                        year, mon_cent, mday, wday,
                        hour, min, sec);

        tmp->tm_sec  = bcd2bin(sec  & 0x7F);
        tmp->tm_min  = bcd2bin(min  & 0x7F);
        tmp->tm_hour = bcd2bin(hour & 0x3F);
        tmp->tm_mday = bcd2bin(mday & 0x3F);
        tmp->tm_mon  = bcd2bin(mon_cent & 0x1F);
        tmp->tm_year = bcd2bin(year) + 2000;
        tmp->tm_wday = bcd2bin(wday & 0x07);
        tmp->tm_yday = 0;
        tmp->tm_isdst = 0;

        return 0;
}

static int  rtc_set_alarm(struct rtc_time *tmp)
{
        unsigned long val;
        struct davinci_rtc *rtc = (struct davinci_rtc *)RTC_BASE;


        printf("Set Alarm at DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
                        tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
                        tmp->tm_hour, tmp->tm_min, tmp->tm_sec);

        writel(bin2bcd(tmp->tm_year % 100), RTC_BASE + 0x94);
        writel(bin2bcd(tmp->tm_mon), RTC_BASE + 0x90);
        writel(bin2bcd(tmp->tm_mday), RTC_BASE + 0x8C);
        writel(bin2bcd(tmp->tm_hour), RTC_BASE + 0x88);
        writel(bin2bcd(tmp->tm_min), RTC_BASE + 0x84);
        writel(bin2bcd(tmp->tm_sec), RTC_BASE + 0x80);

        val = readl(RTC_BASE + 0x48);
        writel((val | OMAP_RTC_INTERRUPTS_IT_ALARM2), RTC_BASE + 0x48);

        val = readl(RTC_BASE+OMAP_RTC_PMIC_REG);
        val = val | OMAP_RTC_PMIC_POWER_EN_EN | OMAP_RTC_PMIC_EXT_WAKEUP_EN
                                                | OMAP_RTC_PMIC_EXT_WAKEUP_POL;
        printf("Read back Alarm2 reg  DATE: %04lx-%02lx-%02lx TIME: %2lx:%02lx:%02lx\n",
                        readl(RTC_BASE + 0x94), readl(RTC_BASE + 0x90), readl(RTC_BASE + 0x8C), readl(RTC_BASE + 0x88),
                        readl(RTC_BASE + 0x84), readl(RTC_BASE + 0x80));
        writel(val, RTC_BASE+OMAP_RTC_PMIC_REG);

        return 0;

}