1 /* SPDX-License-Identifier: GPL-2.0-only */
2
3 #include <commonlib/bsd/bcd.h>
4 #include <console/console.h>
5 #include <device/smbus.h>
6 #include <version.h>
7 #include "chip.h"
8
9 /* Set RTC date from coreboot build date. */
pcf8523_set_build_date(struct device * dev)10 static void pcf8523_set_build_date(struct device *dev)
11 {
12 smbus_write_byte(dev, YEAR_REG, coreboot_build_date.year);
13 smbus_write_byte(dev, MONTH_REG, coreboot_build_date.month);
14 smbus_write_byte(dev, WEEKDAY_REG, coreboot_build_date.weekday);
15 smbus_write_byte(dev, DAY_REG, coreboot_build_date.day);
16 }
17
18 /* Set RTC date from user defined date (available in e.g. device tree). */
pcf8523_set_user_date(struct device * dev)19 static void pcf8523_set_user_date(struct device *dev)
20 {
21 struct drivers_i2c_pcf8523_config *config = dev->chip_info;
22 smbus_write_byte(dev, YEAR_REG, bin2bcd(config->user_year));
23 smbus_write_byte(dev, MONTH_REG, bin2bcd(config->user_month));
24 smbus_write_byte(dev, DAY_REG, bin2bcd(config->user_day));
25 smbus_write_byte(dev, WEEKDAY_REG, bin2bcd(config->user_weekday));
26 }
27
pcf8523_final(struct device * dev)28 static void pcf8523_final(struct device *dev)
29 {
30 /* Read back current RTC date and time and print it to the console. */
31 printk(BIOS_INFO, "%s: Current date %02d.%02d.%02d %02d:%02d:%02d\n",
32 dev->chip_ops->name,
33 bcd2bin(smbus_read_byte(dev, MONTH_REG)),
34 bcd2bin(smbus_read_byte(dev, DAY_REG)),
35 bcd2bin(smbus_read_byte(dev, YEAR_REG)),
36 bcd2bin(smbus_read_byte(dev, HOUR_REG)),
37 bcd2bin(smbus_read_byte(dev, MINUTE_REG)),
38 bcd2bin(smbus_read_byte(dev, SECOND_REG)) & ~OS_BIT);
39 }
40
pcf8523_init(struct device * dev)41 static void pcf8523_init(struct device *dev)
42 {
43 struct drivers_i2c_pcf8523_config *config = dev->chip_info;
44 uint8_t reg = 0;
45
46 if (!(smbus_read_byte(dev, SECOND_REG) & OS_BIT)) {
47 /* Set control registers to a known good value even if no
48 * power loss event was recognized. There were issues with
49 * this RTC in the past where control registers were
50 * corrupted and OS bit was not set. */
51 reg = smbus_read_byte(dev, CTRL_REG_1);
52 reg &= ~(STOP_BIT | CAP_SEL);
53 reg |= ((!!config->cap_sel) << 7);
54 smbus_write_byte(dev, CTRL_REG_1, reg);
55 reg = smbus_read_byte(dev, CTRL_REG_3);
56 reg &= ~PM_MASK;
57 reg |= ((config->power_mode & 0x07) << 5);
58 smbus_write_byte(dev, CTRL_REG_3, reg);
59 reg = smbus_read_byte(dev, TMR_CLKOUT_REG);
60 reg &= ~COF_MASK;
61 reg |= ((config->cof_selection & 0x07) << 3);
62 smbus_write_byte(dev, TMR_CLKOUT_REG, reg);
63 return;
64 }
65
66 /* Initialize the RTC fully only if a power-loss event was recognized.
67 * In this case RTC will be set up with default date and time. */
68 smbus_write_byte(dev, CTRL_REG_1, ((!!config->cap_sel) << 7) |
69 ((!!config->second_int_en) << 2) |
70 ((!!config->alarm_int_en) << 1) |
71 (!!config->correction_int_en));
72
73 smbus_write_byte(dev, CTRL_REG_2, ((!!config->wdt_int_en) << 2) |
74 ((!!config->tmrA_int_en) << 1) |
75 (!!config->tmrB_int_en));
76
77 smbus_write_byte(dev, CTRL_REG_3, ((config->power_mode & 0x07) << 5) |
78 ((!!config->bat_switch_int_en) << 1) |
79 (!!config->bat_low_int_en));
80
81 smbus_write_byte(dev, OFFSET_REG, ((!!config->offset_mode) << 7) |
82 (config->offset_val & 0x7f));
83
84 smbus_write_byte(dev, TMR_CLKOUT_REG, ((!!config->tmrA_int_mode) << 7) |
85 ((!!config->tmrB_int_mode) << 6) |
86 ((config->cof_selection & 0x07) << 3) |
87 ((config->tmrA_mode & 0x03) << 1) |
88 (!!config->tmrB_mode));
89
90 smbus_write_byte(dev, TMR_A_FREQ_REG, (config->tmrA_prescaler & 0x7));
91
92 smbus_write_byte(dev, TMR_B_FREQ_REG, (config->tmrB_prescaler & 0x7) |
93 ((config->tmrB_pulse_cfg & 0x7) << 4));
94
95 /* Before setting the clock stop oscillator. */
96 reg = smbus_read_byte(dev, CTRL_REG_1);
97 reg |= STOP_BIT;
98 smbus_write_byte(dev, CTRL_REG_1, reg);
99 if (config->set_user_date) {
100 /* Set user date defined in device tree. */
101 printk(BIOS_DEBUG, "%s: Set to user date\n",
102 dev->chip_ops->name);
103 pcf8523_set_user_date(dev);
104 } else {
105 /* Set date from coreboot build. */
106 printk(BIOS_DEBUG, "%s: Set to coreboot build date\n",
107 dev->chip_ops->name);
108 pcf8523_set_build_date(dev);
109 }
110 /* Set time to 01:00:00 */
111 smbus_write_byte(dev, HOUR_REG, 1);
112 smbus_write_byte(dev, MINUTE_REG, 0);
113 smbus_write_byte(dev, SECOND_REG, 0);
114 /* Start oscillator again as the clock is set up now */
115 reg &= ~STOP_BIT;
116 smbus_write_byte(dev, CTRL_REG_1, reg);
117 }
118
119 static struct device_operations pcf8523c_ops = {
120 .read_resources = noop_read_resources,
121 .set_resources = noop_set_resources,
122 .init = pcf8523_init,
123 .final = pcf8523_final
124 };
125
pcf8523_enable(struct device * dev)126 static void pcf8523_enable(struct device *dev)
127 {
128 dev->ops = &pcf8523c_ops;
129 }
130
131 struct chip_operations drivers_i2c_pcf8523_ops = {
132 .name = "PCF8523",
133 .enable_dev = pcf8523_enable
134 };
135