| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* This file is part of the coreboot project. */ |
| |
| #include <device/i2c_bus.h> |
| #include <device/device.h> |
| #include <version.h> |
| #include <console/console.h> |
| #include <bcd.h> |
| #include <timer.h> |
| #include "chip.h" |
| #include "rx6110sa.h" |
| |
| /* Function to write a register in the RTC with the given value. */ |
| static void rx6110sa_write(struct device *dev, uint8_t reg, uint8_t val) |
| { |
| i2c_dev_writeb_at(dev, reg, val); |
| } |
| |
| /* Function to read a register in the RTC. */ |
| static uint8_t rx6110sa_read(struct device *dev, uint8_t reg) |
| { |
| return (uint8_t)i2c_dev_readb_at(dev, reg); |
| } |
| |
| /* Set RTC date from coreboot build date. */ |
| static void rx6110sa_set_build_date(struct device *dev) |
| { |
| rx6110sa_write(dev, YEAR_REG, coreboot_build_date.year); |
| rx6110sa_write(dev, MONTH_REG, coreboot_build_date.month); |
| rx6110sa_write(dev, DAY_REG, coreboot_build_date.day); |
| rx6110sa_write(dev, WEEK_REG, (1 << coreboot_build_date.weekday)); |
| } |
| |
| /* Set RTC date from user defined date (available in e.g. device tree). */ |
| static void rx6110sa_set_user_date(struct device *dev) |
| { |
| struct drivers_i2c_rx6110sa_config *config = dev->chip_info; |
| |
| rx6110sa_write(dev, YEAR_REG, bin2bcd(config->user_year)); |
| rx6110sa_write(dev, MONTH_REG, bin2bcd(config->user_month)); |
| rx6110sa_write(dev, DAY_REG, bin2bcd(config->user_day)); |
| rx6110sa_write(dev, WEEK_REG, (1 << config->user_weekday)); |
| } |
| |
| static void rx6110sa_final(struct device *dev) |
| { |
| uint8_t hour, minute, second, year, month, day; |
| |
| /* Read back current RTC date and time and print it to the console. */ |
| hour = rx6110sa_read(dev, HOUR_REG); |
| minute = rx6110sa_read(dev, MINUTE_REG); |
| second = rx6110sa_read(dev, SECOND_REG); |
| year = rx6110sa_read(dev, YEAR_REG); |
| month = rx6110sa_read(dev, MONTH_REG); |
| day = rx6110sa_read(dev, DAY_REG); |
| |
| printk(BIOS_INFO, "%s: Current date %02d.%02d.%02d %02d:%02d:%02d\n", |
| dev->chip_ops->name, bcd2bin(month), bcd2bin(day), |
| bcd2bin(year), bcd2bin(hour), bcd2bin(minute), bcd2bin(second)); |
| } |
| |
| static void rx6110sa_init(struct device *dev) |
| { |
| struct drivers_i2c_rx6110sa_config *config = dev->chip_info; |
| uint8_t reg, flags; |
| struct stopwatch sw; |
| |
| /* Do a dummy read first as requested in the datasheet. */ |
| rx6110sa_read(dev, SECOND_REG); |
| /* Check power loss status by reading the VLF-bit. */ |
| flags = rx6110sa_read(dev, FLAG_REGISTER); |
| if (flags & VLF_BIT) { |
| /* |
| * Voltage low detected, perform RX6110 SA reset sequence as |
| * requested in the datasheet. The meaning of the registers 0x60 |
| * and above is not documented in the datasheet, they have to be |
| * used as requested according to Epson. |
| */ |
| rx6110sa_write(dev, BATTERY_BACKUP_REG, 0x00); |
| rx6110sa_write(dev, CTRL_REG, 0x00); |
| rx6110sa_write(dev, CTRL_REG, TEST_BIT); |
| rx6110sa_write(dev, 0x60, 0xd3); |
| rx6110sa_write(dev, 0x66, 0x03); |
| rx6110sa_write(dev, 0x6b, 0x02); |
| rx6110sa_write(dev, 0x6b, 0x01); |
| /* According to the datasheet one have to wait for at least 2 ms |
| * before the VLF bit can be cleared in the flag register after |
| * this reset sequence. As the other registers are still |
| * accessible use the stopwatch to parallel the flow. |
| */ |
| stopwatch_init_msecs_expire(&sw, AFTER_RESET_DELAY_MS); |
| } |
| /* |
| * Set up important registers even if there was no power loss to make |
| * sure that the right mode is used as it directly influences the |
| * backup current consumption and therefore the backup time. These |
| * settings do not change current date and time and the RTC will not |
| * be stopped while the registers are set up. |
| */ |
| reg = (config->pmon_sampling & PMON_SAMPL_MASK) | |
| (!!config->bks_off << 2) | (!!config->bks_on << 3) | |
| (!!config->iocut_en << 4); |
| rx6110sa_write(dev, BATTERY_BACKUP_REG, reg); |
| |
| /* Clear timer enable bit and set frequency of clock output. */ |
| reg = rx6110sa_read(dev, EXTENSION_REG); |
| reg &= ~(FSEL_MASK); |
| reg |= ((config->cof_selection << 6) & FSEL_MASK); |
| if (config->timer_preset) { |
| /* Timer needs to be in stop mode prior to programming it. */ |
| if (reg & TE_BIT) { |
| reg &= ~TE_BIT; |
| rx6110sa_write(dev, EXTENSION_REG, reg); |
| } |
| /* Program the timer preset value. */ |
| rx6110sa_write(dev, TMR_COUNTER_0_REG, |
| config->timer_preset & 0xff); |
| rx6110sa_write(dev, TMR_COUNTER_1_REG, |
| (config->timer_preset >> 8) & 0xff); |
| /* Set Timer Enable bit and the timer clock value. */ |
| reg &= ~TSEL_MASK; |
| reg |= ((!!config->timer_en << 4) | |
| (config->timer_clk & TSEL_MASK)); |
| } |
| rx6110sa_write(dev, EXTENSION_REG, reg); |
| rx6110sa_write(dev, CTRL_REG, 0x00); |
| rx6110sa_write(dev, DIGITAL_REG, 0x00); |
| rx6110sa_write(dev, RESERVED_BIT_REG, RTC_INIT_VALUE); |
| reg = (!!config->enable_1hz_out << 4) | |
| (!!config->irq_output_pin << 2) | |
| (config->fout_output_pin & FOUT_OUTPUT_PIN_MASK); |
| rx6110sa_write(dev, IRQ_CONTROL_REG, reg); |
| /* If there was no power loss event no further steps are needed. */ |
| if (!(flags & VLF_BIT)) |
| return; |
| /* There was a power loss event, clear voltage low detect bit. |
| * Take the needed delay after a reset sequence into account before the |
| * VLF-bit can be cleared. |
| */ |
| stopwatch_wait_until_expired(&sw); |
| flags &= ~VLF_BIT; |
| rx6110sa_write(dev, FLAG_REGISTER, flags); |
| |
| /* Before setting the clock stop oscillator. */ |
| rx6110sa_write(dev, CTRL_REG, STOP_BIT); |
| |
| 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); |
| rx6110sa_set_user_date(dev); |
| } else { |
| /* Set date from coreboot build. */ |
| printk(BIOS_DEBUG, "%s: Set to coreboot build date\n", |
| dev->chip_ops->name); |
| rx6110sa_set_build_date(dev); |
| } |
| rx6110sa_write(dev, HOUR_REG, 1); |
| rx6110sa_write(dev, MINUTE_REG, 0); |
| rx6110sa_write(dev, SECOND_REG, 0); |
| /* Start oscillator again as the RTC is set up now. */ |
| reg = (!!config->timer_irq_en << 4) | |
| (config->timer_mode & TMR_MODE_MASK); |
| rx6110sa_write(dev, CTRL_REG, reg); |
| } |
| |
| static struct device_operations rx6110sa_ops = { |
| .read_resources = noop_read_resources, |
| .set_resources = noop_set_resources, |
| .init = rx6110sa_init, |
| .final = rx6110sa_final |
| }; |
| |
| static void rx6110sa_enable(struct device *dev) |
| { |
| dev->ops = &rx6110sa_ops; |
| } |
| |
| struct chip_operations drivers_i2c_rx6110sa_ops = { |
| CHIP_NAME("RX6110 SA") |
| .enable_dev = rx6110sa_enable |
| }; |