diff options
Diffstat (limited to 'drivers/rtc')
| -rw-r--r-- | drivers/rtc/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/rtc/emul_rtc.c | 28 | ||||
| -rw-r--r-- | drivers/rtc/m41t62.c | 139 | ||||
| -rw-r--r-- | drivers/rtc/mc146818.c | 4 | ||||
| -rw-r--r-- | drivers/rtc/rtc-uclass.c | 2 | ||||
| -rw-r--r-- | drivers/rtc/sandbox_rtc.c | 4 |
6 files changed, 169 insertions, 21 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index d06d272e14..cad667a404 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -68,11 +68,14 @@ config RTC_EMULATION depends on DM_RTC help On a board without hardware clock this software real time clock can be - used. The build time is used to initialize the RTC. So you will have - to adjust the time either manually using the 'date' command or use - the 'sntp' to update the RTC with the time from a network time server. - See CONFIG_CMD_SNTP and CONFIG_BOOTP_NTPSERVER. The RTC time is - advanced according to CPU ticks. + used. The initial time may be provided via the environment variable + 'rtc_emul_epoch' as a decimal string indicating seconds since + 1970-01-01. If the environment variable is missing, the build time is + used to initialize the RTC. The time can be adjusted manually via the + 'date' command or the 'sntp' command can be used to update the RTC + with the time from a network time server. See CONFIG_CMD_SNTP and + CONFIG_BOOTP_NTPSERVER. The RTC time is advanced according to CPU + ticks. config RTC_ISL1208 bool "Enable ISL1208 driver" diff --git a/drivers/rtc/emul_rtc.c b/drivers/rtc/emul_rtc.c index c98c24bbb3..7e522103fd 100644 --- a/drivers/rtc/emul_rtc.c +++ b/drivers/rtc/emul_rtc.c @@ -8,6 +8,7 @@ #include <common.h> #include <div64.h> #include <dm.h> +#include <env.h> #include <generated/timestamp_autogenerated.h> #include <rtc.h> @@ -30,12 +31,6 @@ static int emul_rtc_get(struct udevice *dev, struct rtc_time *time) struct emul_rtc *priv = dev_get_priv(dev); u64 now; - if (!priv->offset_us) { - /* Use the build date as initial time */ - priv->offset_us = U_BOOT_EPOCH * 1000000ULL - timer_get_us(); - priv->isdst = -1; - } - now = timer_get_us() + priv->offset_us; do_div(now, 1000000); rtc_to_tm(now, time); @@ -63,6 +58,26 @@ static int emul_rtc_set(struct udevice *dev, const struct rtc_time *time) 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, @@ -72,6 +87,7 @@ U_BOOT_DRIVER(rtc_emul) = { .name = "rtc_emul", .id = UCLASS_RTC, .ops = &emul_rtc_ops, + .probe = emul_rtc_probe, .priv_auto_alloc_size = sizeof(struct emul_rtc), }; diff --git a/drivers/rtc/m41t62.c b/drivers/rtc/m41t62.c index 94a6b523aa..0a4e12d698 100644 --- a/drivers/rtc/m41t62.c +++ b/drivers/rtc/m41t62.c @@ -22,6 +22,8 @@ #include <log.h> #include <rtc.h> #include <i2c.h> +#include <linux/log2.h> +#include <linux/delay.h> #define M41T62_REG_SSEC 0 #define M41T62_REG_SEC 1 @@ -47,8 +49,14 @@ #define M41T62_ALMON_SQWE (1 << 6) /* SQWE: SQW Enable Bit */ #define M41T62_ALHOUR_HT (1 << 6) /* HT: Halt Update Bit */ #define M41T62_FLAGS_AF (1 << 6) /* AF: Alarm Flag Bit */ +#define M41T62_FLAGS_OF (1 << 2) /* OF: Oscillator Flag Bit */ #define M41T62_FLAGS_BATT_LOW (1 << 4) /* BL: Battery Low Bit */ +#define M41T62_WDAY_SQW_FREQ_MASK 0xf0 +#define M41T62_WDAY_SQW_FREQ_SHIFT 4 + +#define M41T62_SQW_MAX_FREQ 32768 + #define M41T62_FEATURE_HT (1 << 0) #define M41T62_FEATURE_BL (1 << 1) @@ -139,21 +147,140 @@ static int m41t62_rtc_set(struct udevice *dev, const struct rtc_time *tm) return 0; } -static int m41t62_rtc_reset(struct udevice *dev) +static int m41t62_sqw_enable(struct udevice *dev, bool enable) { u8 val; + int ret; + + ret = dm_i2c_read(dev, M41T62_REG_ALARM_MON, &val, sizeof(val)); + if (ret) + return ret; + + if (enable) + val |= M41T62_ALMON_SQWE; + else + val &= ~M41T62_ALMON_SQWE; + + return dm_i2c_write(dev, M41T62_REG_ALARM_MON, &val, sizeof(val)); +} + +static int m41t62_sqw_set_rate(struct udevice *dev, unsigned int rate) +{ + u8 val, newval, sqwrateval; + int ret; + + if (rate >= M41T62_SQW_MAX_FREQ) + sqwrateval = 1; + else if (rate >= M41T62_SQW_MAX_FREQ / 4) + sqwrateval = 2; + else if (rate) + sqwrateval = 15 - ilog2(rate); + + ret = dm_i2c_read(dev, M41T62_REG_WDAY, &val, sizeof(val)); + if (ret) + return ret; + + newval = val; + newval &= ~M41T62_WDAY_SQW_FREQ_MASK; + newval |= (sqwrateval << M41T62_WDAY_SQW_FREQ_SHIFT); + + /* + * Try to avoid writing unchanged values. Writing to this register + * will reset the internal counter pipeline and thus affect system + * time. + */ + if (newval == val) + return 0; + + return dm_i2c_write(dev, M41T62_REG_WDAY, &newval, sizeof(newval)); +} + +static int m41t62_rtc_restart_osc(struct udevice *dev) +{ + u8 val; + int ret; + + /* 0. check if oscillator failure happened */ + ret = dm_i2c_read(dev, M41T62_REG_FLAGS, &val, sizeof(val)); + if (ret) + return ret; + if (!(val & M41T62_FLAGS_OF)) + return 0; + + ret = dm_i2c_read(dev, M41T62_REG_SEC, &val, sizeof(val)); + if (ret) + return ret; + + /* 1. Set stop bit */ + val |= M41T62_SEC_ST; + ret = dm_i2c_write(dev, M41T62_REG_ALARM_HOUR, &val, sizeof(val)); + if (ret) + return ret; + + /* 2. Clear stop bit */ + val &= ~M41T62_SEC_ST; + ret = dm_i2c_write(dev, M41T62_REG_ALARM_HOUR, &val, sizeof(val)); + if (ret) + return ret; + + /* 3. wait 4 seconds */ + mdelay(4000); + + ret = dm_i2c_read(dev, M41T62_REG_FLAGS, &val, sizeof(val)); + if (ret) + return ret; + + /* 4. clear M41T62_FLAGS_OF bit */ + val &= ~M41T62_FLAGS_OF; + ret = dm_i2c_write(dev, M41T62_REG_FLAGS, &val, sizeof(val)); + if (ret) + return ret; + + return 0; +} + +static int m41t62_rtc_clear_ht(struct udevice *dev) +{ + u8 val; + int ret; /* * M41T82: Make sure HT (Halt Update) bit is cleared. * This bit is 0 in M41T62 so its save to clear it always. */ - int ret = dm_i2c_read(dev, M41T62_REG_ALARM_HOUR, &val, sizeof(val)); - + ret = dm_i2c_read(dev, M41T62_REG_ALARM_HOUR, &val, sizeof(val)); + if (ret) + return ret; val &= ~M41T80_ALHOUR_HT; - ret |= dm_i2c_write(dev, M41T62_REG_ALARM_HOUR, &val, sizeof(val)); + ret = dm_i2c_write(dev, M41T62_REG_ALARM_HOUR, &val, sizeof(val)); + if (ret) + return ret; + + return 0; +} + +static int m41t62_rtc_reset(struct udevice *dev) +{ + int ret; + + ret = m41t62_rtc_restart_osc(dev); + if (ret) + return ret; + + ret = m41t62_rtc_clear_ht(dev); + if (ret) + return ret; - return ret; + /* + * Some boards feed the square wave as clock input into + * the SoC. This enables a 32.768kHz square wave, which is + * also the hardware default after power-loss. + */ + ret = m41t62_sqw_set_rate(dev, 32768); + if (ret) + return ret; + return m41t62_sqw_enable(dev, true); } /* @@ -162,7 +289,7 @@ static int m41t62_rtc_reset(struct udevice *dev) */ static int m41t62_rtc_probe(struct udevice *dev) { - return m41t62_rtc_reset(dev); + return m41t62_rtc_clear_ht(dev); } static const struct rtc_ops m41t62_rtc_ops = { diff --git a/drivers/rtc/mc146818.c b/drivers/rtc/mc146818.c index b98c39d821..71f96e282e 100644 --- a/drivers/rtc/mc146818.c +++ b/drivers/rtc/mc146818.c @@ -246,8 +246,8 @@ static const struct udevice_id rtc_mc146818_ids[] = { { } }; -U_BOOT_DRIVER(rtc_mc146818) = { - .name = "rtc_mc146818", +U_BOOT_DRIVER(motorola_mc146818) = { + .name = "motorola_mc146818", .id = UCLASS_RTC, .of_match = rtc_mc146818_ids, .probe = rtc_mc146818_probe, diff --git a/drivers/rtc/rtc-uclass.c b/drivers/rtc/rtc-uclass.c index 8035f7fe9c..b406bab32d 100644 --- a/drivers/rtc/rtc-uclass.c +++ b/drivers/rtc/rtc-uclass.c @@ -174,5 +174,7 @@ int rtc_write32(struct udevice *dev, unsigned int reg, u32 value) UCLASS_DRIVER(rtc) = { .name = "rtc", .id = UCLASS_RTC, +#if !CONFIG_IS_ENABLED(OF_PLATDATA) .post_bind = dm_scan_fdt_dev, +#endif }; diff --git a/drivers/rtc/sandbox_rtc.c b/drivers/rtc/sandbox_rtc.c index 852770a49c..d0864b1df9 100644 --- a/drivers/rtc/sandbox_rtc.c +++ b/drivers/rtc/sandbox_rtc.c @@ -92,8 +92,8 @@ static const struct udevice_id sandbox_rtc_ids[] = { { } }; -U_BOOT_DRIVER(rtc_sandbox) = { - .name = "rtc-sandbox", +U_BOOT_DRIVER(sandbox_rtc) = { + .name = "sandbox_rtc", .id = UCLASS_RTC, .of_match = sandbox_rtc_ids, .ops = &sandbox_rtc_ops, |