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/*
* This file is part of the coreboot project.
*
* Copyright 2016 Siemens AG.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <device/smbus.h>
#include <version.h>
#include <console/console.h>
#include <bcd.h>
#include "chip.h"
/* Set RTC date from coreboot build date. */
static void pcf8523_set_build_date(struct device *dev)
{
smbus_write_byte(dev, YEAR_REG, coreboot_build_date.year);
smbus_write_byte(dev, MONTH_REG, coreboot_build_date.month);
smbus_write_byte(dev, WEEKDAY_REG, coreboot_build_date.weekday);
smbus_write_byte(dev, DAY_REG, coreboot_build_date.day);
}
/* Set RTC date from user defined date (available in e.g. device tree). */
static void pcf8523_set_user_date(struct device *dev)
{
struct drivers_i2c_pcf8523_config *config = dev->chip_info;
smbus_write_byte(dev, YEAR_REG, bin2bcd(config->user_year));
smbus_write_byte(dev, MONTH_REG, bin2bcd(config->user_month));
smbus_write_byte(dev, DAY_REG, bin2bcd(config->user_day));
smbus_write_byte(dev, WEEKDAY_REG, bin2bcd(config->user_weekday));
}
static void pcf8523_final(struct device *dev)
{
/* Read back current RTC date and time and print it to the console. */
printk(BIOS_INFO, "%s: Current date %02d.%02d.%02d %02d:%02d:%02d\n",
dev->chip_ops->name,
bcd2bin(smbus_read_byte(dev, MONTH_REG)),
bcd2bin(smbus_read_byte(dev, DAY_REG)),
bcd2bin(smbus_read_byte(dev, YEAR_REG)),
bcd2bin(smbus_read_byte(dev, HOUR_REG)),
bcd2bin(smbus_read_byte(dev, MINUTE_REG)),
bcd2bin(smbus_read_byte(dev, SECOND_REG)) & ~OS_BIT);
}
static void pcf8523_init(struct device *dev)
{
struct drivers_i2c_pcf8523_config *config = dev->chip_info;
uint8_t reg = 0;
if (!(smbus_read_byte(dev, SECOND_REG) & OS_BIT)) {
/* Set control registers to a known good value even if no
* power loss event was recognized. There were issues with
* this RTC in the past where control registers were
* corrupted and OS bit was not set. */
reg = smbus_read_byte(dev, CTRL_REG_1);
reg &= ~(STOP_BIT | CAP_SEL);
reg |= config->cap_sel;
smbus_write_byte(dev, CTRL_REG_1, reg);
reg = smbus_read_byte(dev, CTRL_REG_3);
reg &= ~PM_MASK;
reg |= config->power_mode;
smbus_write_byte(dev, CTRL_REG_3, reg);
reg = smbus_read_byte(dev, TMR_CLKOUT_REG);
reg &= ~COF_MASK;
reg |= config->cof_selection;
smbus_write_byte(dev, TMR_CLKOUT_REG, reg);
return;
}
/* Initialize the RTC fully only if a power-loss event was recognized.
* In this case RTC will be set up with default date and time. */
smbus_write_byte(dev, CTRL_REG_1, ((!!config->cap_sel) << 7) |
((!!config->second_int_en) << 2) |
((!!config->alarm_int_en) << 1) |
(!!config->correction_int_en));
smbus_write_byte(dev, CTRL_REG_2, ((!!config->wdt_int_en) << 2) |
((!!config->tmrA_int_en) << 1) |
(!!config->tmrB_int_en));
smbus_write_byte(dev, CTRL_REG_3, ((config->power_mode & 0x03) << 5) |
((!!config->bat_switch_int_en) << 1) |
(!!config->bat_low_int_en));
smbus_write_byte(dev, OFFSET_REG, ((!!config->offset_mode) << 7) |
(config->offset_val & 0x7f));
smbus_write_byte(dev, TMR_CLKOUT_REG, ((!!config->tmrA_int_mode) << 7) |
((!!config->tmrB_int_mode) << 6) |
((config->cof_selection & 0x38) << 3) |
((config->tmrA_mode & 0x03) << 1) |
(!!config->tmrB_mode));
smbus_write_byte(dev, TMR_A_FREQ_REG, (config->tmrA_prescaler & 0x7));
smbus_write_byte(dev, TMR_B_FREQ_REG, (config->tmrB_prescaler & 0x7) |
((config->tmrB_pulse_cfg & 0x7) << 4));
/* Before setting the clock stop oscillator. */
reg = smbus_read_byte(dev, CTRL_REG_1);
reg |= STOP_BIT;
smbus_write_byte(dev, CTRL_REG_1, reg);
if (config->set_user_date) {
/* Set user date defined in device tree. */
printk(BIOS_DEBUG, "%s: Set to user date\n",
dev->chip_ops->name);
pcf8523_set_user_date(dev);
} else {
/* Set date from coreboot build. */
printk(BIOS_DEBUG, "%s: Set to coreboot build date\n",
dev->chip_ops->name);
pcf8523_set_build_date(dev);
}
/* Set time to 01:00:00 */
smbus_write_byte(dev, HOUR_REG, 1);
smbus_write_byte(dev, MINUTE_REG, 0);
smbus_write_byte(dev, SECOND_REG, 0);
/* Start oscillator again as the clock is set up now */
reg &= ~STOP_BIT;
smbus_write_byte(dev, CTRL_REG_1, reg);
}
static struct device_operations pcf8523c_ops = {
.read_resources = DEVICE_NOOP,
.set_resources = DEVICE_NOOP,
.enable_resources = DEVICE_NOOP,
.init = pcf8523_init,
.final = pcf8523_final
};
static void pcf8523_enable(struct device *dev)
{
dev->ops = &pcf8523c_ops;
}
struct chip_operations drivers_i2c_pcf8523_ops = {
CHIP_NAME("PCF8523")
.enable_dev = pcf8523_enable
};
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