diff options
Diffstat (limited to 'drivers/rtc')
| -rw-r--r-- | drivers/rtc/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/rtc/Makefile | 1 | ||||
| -rw-r--r-- | drivers/rtc/goldfish_rtc.c | 105 |
3 files changed, 113 insertions, 0 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 23173139e0..7fc53a6d61 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -122,6 +122,13 @@ config RTC_EMULATION CONFIG_BOOTP_NTPSERVER. The RTC time is advanced according to CPU ticks. +config RTC_GOLDFISH + bool "Enable Goldfish driver" + depends on DM_RTC + help + The Goldfish RTC is a virtual device which may be supplied by QEMU. + It is enabled by default on QEMU's RISC-V virt machine. + config RTC_ISL1208 bool "Enable ISL1208 driver" depends on DM_RTC diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 308fab8da9..03a424c31a 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -15,6 +15,7 @@ obj-$(CONFIG_RTC_DS1374) += ds1374.o obj-$(CONFIG_RTC_DS3231) += ds3231.o obj-$(CONFIG_RTC_DS3232) += ds3232.o obj-$(CONFIG_RTC_EMULATION) += emul_rtc.o +obj-$(CONFIG_RTC_GOLDFISH) += goldfish_rtc.o obj-$(CONFIG_RTC_HT1380) += ht1380.o obj-$(CONFIG_$(SPL_TPL_)RTC_SANDBOX) += i2c_rtc_emul.o obj-$(CONFIG_RTC_ISL1208) += isl1208.o diff --git a/drivers/rtc/goldfish_rtc.c b/drivers/rtc/goldfish_rtc.c new file mode 100644 index 0000000000..1ace990385 --- /dev/null +++ b/drivers/rtc/goldfish_rtc.c @@ -0,0 +1,105 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2023, Heinrich Schuchardt <heinrich.schuchardt@canonical.com> + * + * This driver emulates a real time clock based on timer ticks. + */ + +#include <div64.h> +#include <dm.h> +#include <mapmem.h> +#include <rtc.h> +#include <linux/io.h> + +/** + * struct goldfish_rtc - private data for RTC driver + */ +struct goldfish_rtc { + /** + * @base: base address for register file + */ + void __iomem *base; + /** + * @isdst: daylight saving time + */ + int isdst; +}; + +/* Register offsets */ +#define GOLDFISH_TIME_LOW 0x00 +#define GOLDFISH_TIME_HIGH 0x04 + +static int goldfish_rtc_get(struct udevice *dev, struct rtc_time *time) +{ + struct goldfish_rtc *priv = dev_get_priv(dev); + void __iomem *base = priv->base; + u64 time_high; + u64 time_low; + u64 now; + + time_low = ioread32(base + GOLDFISH_TIME_LOW); + time_high = ioread32(base + GOLDFISH_TIME_HIGH); + now = (time_high << 32) | time_low; + + do_div(now, 1000000000U); + + rtc_to_tm(now, time); + time->tm_isdst = priv->isdst; + + return 0; +} + +static int goldfish_rtc_set(struct udevice *dev, const struct rtc_time *time) +{ + struct goldfish_rtc *priv = dev_get_priv(dev); + void __iomem *base = priv->base; + u64 now; + + if (time->tm_year < 1970) + return -EINVAL; + + now = rtc_mktime(time) * 1000000000ULL; + iowrite32(now >> 32, base + GOLDFISH_TIME_HIGH); + iowrite32(now, base + GOLDFISH_TIME_LOW); + + if (time->tm_isdst > 0) + priv->isdst = 1; + else if (time->tm_isdst < 0) + priv->isdst = -1; + else + priv->isdst = 0; + + return 0; +} + +int goldfish_rtc_probe(struct udevice *dev) +{ + struct goldfish_rtc *priv = dev_get_priv(dev); + fdt_addr_t addr; + + addr = dev_read_addr(dev); + if (addr == FDT_ADDR_T_NONE) + return -EINVAL; + priv->base = map_sysmem(addr, 0x20); + + return 0; +} + +static const struct rtc_ops goldfish_rtc_ops = { + .get = goldfish_rtc_get, + .set = goldfish_rtc_set, +}; + +static const struct udevice_id goldfish_rtc_of_match[] = { + { .compatible = "google,goldfish-rtc", }, + {}, +}; + +U_BOOT_DRIVER(rtc_goldfish) = { + .name = "rtc_goldfish", + .id = UCLASS_RTC, + .ops = &goldfish_rtc_ops, + .probe = goldfish_rtc_probe, + .of_match = goldfish_rtc_of_match, + .priv_auto = sizeof(struct goldfish_rtc), +}; |