u-boot/drivers/rtc/emul_rtc.c
Tom Rini d678a59d2d Revert "Merge patch series "arm: dts: am62-beagleplay: Fix Beagleplay Ethernet""
When bringing in the series 'arm: dts: am62-beagleplay: Fix Beagleplay
Ethernet"' I failed to notice that b4 noticed it was based on next and
so took that as the base commit and merged that part of next to master.

This reverts commit c8ffd1356d, reversing
changes made to 2ee6f3a5f7.

Reported-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Tom Rini <trini@konsulko.com>
2024-05-19 08:16:36 -06:00

97 lines
1.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
*
* This driver emulates a real time clock based on timer ticks.
*/
#include <common.h>
#include <div64.h>
#include <dm.h>
#include <env.h>
#include <rtc.h>
#include <timestamp.h>
/**
* struct emul_rtc - private data for emulated RTC driver
*/
struct emul_rtc {
/**
* @offset_us: microseconds from 1970-01-01 to timer_get_us() base
*/
u64 offset_us;
/**
* @isdst: daylight saving time
*/
int isdst;
};
static int emul_rtc_get(struct udevice *dev, struct rtc_time *time)
{
struct emul_rtc *priv = dev_get_priv(dev);
u64 now;
now = timer_get_us() + priv->offset_us;
do_div(now, 1000000);
rtc_to_tm(now, time);
time->tm_isdst = priv->isdst;
return 0;
}
static int emul_rtc_set(struct udevice *dev, const struct rtc_time *time)
{
struct emul_rtc *priv = dev_get_priv(dev);
if (time->tm_year < 1970)
return -EINVAL;
priv->offset_us = rtc_mktime(time) * 1000000ULL - timer_get_us();
if (time->tm_isdst > 0)
priv->isdst = 1;
else if (time->tm_isdst < 0)
priv->isdst = -1;
else
priv->isdst = 0;
return 0;
}
int emul_rtc_probe(struct udevice *dev)
{
struct emul_rtc *priv = dev_get_priv(dev);
const char *epoch_str;
u64 epoch;
epoch_str = env_get("rtc_emul_epoch");
if (epoch_str) {
epoch = simple_strtoull(epoch_str, NULL, 10);
} else {
/* Use the build date as initial time */
epoch = U_BOOT_EPOCH;
}
priv->offset_us = epoch * 1000000ULL - timer_get_us();
priv->isdst = -1;
return 0;
}
static const struct rtc_ops emul_rtc_ops = {
.get = emul_rtc_get,
.set = emul_rtc_set,
};
U_BOOT_DRIVER(rtc_emul) = {
.name = "rtc_emul",
.id = UCLASS_RTC,
.ops = &emul_rtc_ops,
.probe = emul_rtc_probe,
.priv_auto = sizeof(struct emul_rtc),
};
U_BOOT_DRVINFO(rtc_emul) = {
.name = "rtc_emul",
};