projects / u-boot.git / blame
| Commit | Line | Data |
|---|---|---|
| 87e9963d HS |
1 | // SPDX-License-Identifier: GPL-2.0+ |
| 2 | /* | |
| 3 | * Copyright 2020, Heinrich Schuchardt <[email protected]> | |
| 4 | * | |
| 5 | * This driver emulates a real time clock based on timer ticks. | |
| 6 | */ | |
| 7 | ||
| 8 | #include <common.h> | |
| 9 | #include <div64.h> | |
| 10 | #include <dm.h> | |
| fb71c3f4 | 11 | #include <env.h> |
| 87e9963d HS |
12 | #include <generated/timestamp_autogenerated.h> |
| 13 | #include <rtc.h> | |
| 14 | ||
| 15 | /** | |
| 16 | * struct emul_rtc - private data for emulated RTC driver | |
| 17 | */ | |
| 18 | struct emul_rtc { | |
| 19 | /** | |
| 20 | * @offset_us: microseconds from 1970-01-01 to timer_get_us() base | |
| 21 | */ | |
| 22 | u64 offset_us; | |
| 23 | /** | |
| 24 | * @isdst: daylight saving time | |
| 25 | */ | |
| 26 | int isdst; | |
| 27 | }; | |
| 28 | ||
| 29 | static int emul_rtc_get(struct udevice *dev, struct rtc_time *time) | |
| 30 | { | |
| 31 | struct emul_rtc *priv = dev_get_priv(dev); | |
| 32 | u64 now; | |
| 33 | ||
| 87e9963d HS |
34 | now = timer_get_us() + priv->offset_us; |
| 35 | do_div(now, 1000000); | |
| 36 | rtc_to_tm(now, time); | |
| 37 | time->tm_isdst = priv->isdst; | |
| 38 | ||
| 39 | return 0; | |
| 40 | } | |
| 41 | ||
| 42 | static int emul_rtc_set(struct udevice *dev, const struct rtc_time *time) | |
| 43 | { | |
| 44 | struct emul_rtc *priv = dev_get_priv(dev); | |
| 45 | ||
| 46 | if (time->tm_year < 1970) | |
| 47 | return -EINVAL; | |
| 48 | ||
| 49 | priv->offset_us = rtc_mktime(time) * 1000000ULL - timer_get_us(); | |
| 50 | ||
| 51 | if (time->tm_isdst > 0) | |
| 52 | priv->isdst = 1; | |
| 53 | else if (time->tm_isdst < 0) | |
| 54 | priv->isdst = -1; | |
| 55 | else | |
| 56 | priv->isdst = 0; | |
| 57 | ||
| 58 | return 0; | |
| 59 | } | |
| 60 | ||
| 0ca4b558 HS |
61 | int emul_rtc_probe(struct udevice *dev) |
| 62 | { | |
| 63 | struct emul_rtc *priv = dev_get_priv(dev); | |
| fb71c3f4 HS |
64 | const char *epoch_str; |
| 65 | u64 epoch; | |
| 66 | ||
| 67 | epoch_str = env_get("rtc_emul_epoch"); | |
| 68 | ||
| 69 | if (epoch_str) { | |
| 70 | epoch = simple_strtoull(epoch_str, NULL, 10); | |
| 71 | } else { | |
| 72 | /* Use the build date as initial time */ | |
| 73 | epoch = U_BOOT_EPOCH; | |
| 74 | } | |
| 75 | priv->offset_us = epoch * 1000000ULL - timer_get_us(); | |
| 0ca4b558 HS |
76 | priv->isdst = -1; |
| 77 | ||
| 78 | return 0; | |
| 79 | } | |
| 80 | ||
| 87e9963d HS |
81 | static const struct rtc_ops emul_rtc_ops = { |
| 82 | .get = emul_rtc_get, | |
| 83 | .set = emul_rtc_set, | |
| 84 | }; | |
| 85 | ||
| 86 | U_BOOT_DRIVER(rtc_emul) = { | |
| 87 | .name = "rtc_emul", | |
| 88 | .id = UCLASS_RTC, | |
| 89 | .ops = &emul_rtc_ops, | |
| 0ca4b558 | 90 | .probe = emul_rtc_probe, |
| 41575d8e | 91 | .priv_auto = sizeof(struct emul_rtc), |
| 87e9963d HS |
92 | }; |
| 93 | ||
| 94 | U_BOOT_DEVICE(rtc_emul) = { | |
| 95 | .name = "rtc_emul", | |
| 96 | }; |