diff options
Diffstat (limited to 'drivers/rtc/rtc-ls1x.c')
| -rw-r--r-- | drivers/rtc/rtc-ls1x.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ls1x.c b/drivers/rtc/rtc-ls1x.c new file mode 100644 index 000000000..5af26dc5c --- /dev/null +++ b/drivers/rtc/rtc-ls1x.c @@ -0,0 +1,192 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2011 Zhao Zhang <zhzhl555@gmail.com> + * + * Derived from driver/rtc/rtc-au1xxx.c + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/rtc.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/delay.h> +#include <linux/types.h> +#include <linux/io.h> +#include <loongson1.h> + +#define LS1X_RTC_REG_OFFSET (LS1X_RTC_BASE + 0x20) +#define LS1X_RTC_REGS(x) \ + ((void __iomem *)KSEG1ADDR(LS1X_RTC_REG_OFFSET + (x))) + +/*RTC programmable counters 0 and 1*/ +#define SYS_COUNTER_CNTRL (LS1X_RTC_REGS(0x20)) +#define SYS_CNTRL_ERS (1 << 23) +#define SYS_CNTRL_RTS (1 << 20) +#define SYS_CNTRL_RM2 (1 << 19) +#define SYS_CNTRL_RM1 (1 << 18) +#define SYS_CNTRL_RM0 (1 << 17) +#define SYS_CNTRL_RS (1 << 16) +#define SYS_CNTRL_BP (1 << 14) +#define SYS_CNTRL_REN (1 << 13) +#define SYS_CNTRL_BRT (1 << 12) +#define SYS_CNTRL_TEN (1 << 11) +#define SYS_CNTRL_BTT (1 << 10) +#define SYS_CNTRL_E0 (1 << 8) +#define SYS_CNTRL_ETS (1 << 7) +#define SYS_CNTRL_32S (1 << 5) +#define SYS_CNTRL_TTS (1 << 4) +#define SYS_CNTRL_TM2 (1 << 3) +#define SYS_CNTRL_TM1 (1 << 2) +#define SYS_CNTRL_TM0 (1 << 1) +#define SYS_CNTRL_TS (1 << 0) + +/* Programmable Counter 0 Registers */ +#define SYS_TOYTRIM (LS1X_RTC_REGS(0)) +#define SYS_TOYWRITE0 (LS1X_RTC_REGS(4)) +#define SYS_TOYWRITE1 (LS1X_RTC_REGS(8)) +#define SYS_TOYREAD0 (LS1X_RTC_REGS(0xC)) +#define SYS_TOYREAD1 (LS1X_RTC_REGS(0x10)) +#define SYS_TOYMATCH0 (LS1X_RTC_REGS(0x14)) +#define SYS_TOYMATCH1 (LS1X_RTC_REGS(0x18)) +#define SYS_TOYMATCH2 (LS1X_RTC_REGS(0x1C)) + +/* Programmable Counter 1 Registers */ +#define SYS_RTCTRIM (LS1X_RTC_REGS(0x40)) +#define SYS_RTCWRITE0 (LS1X_RTC_REGS(0x44)) +#define SYS_RTCREAD0 (LS1X_RTC_REGS(0x48)) +#define SYS_RTCMATCH0 (LS1X_RTC_REGS(0x4C)) +#define SYS_RTCMATCH1 (LS1X_RTC_REGS(0x50)) +#define SYS_RTCMATCH2 (LS1X_RTC_REGS(0x54)) + +#define LS1X_SEC_OFFSET (4) +#define LS1X_MIN_OFFSET (10) +#define LS1X_HOUR_OFFSET (16) +#define LS1X_DAY_OFFSET (21) +#define LS1X_MONTH_OFFSET (26) + + +#define LS1X_SEC_MASK (0x3f) +#define LS1X_MIN_MASK (0x3f) +#define LS1X_HOUR_MASK (0x1f) +#define LS1X_DAY_MASK (0x1f) +#define LS1X_MONTH_MASK (0x3f) +#define LS1X_YEAR_MASK (0xffffffff) + +#define ls1x_get_sec(t) (((t) >> LS1X_SEC_OFFSET) & LS1X_SEC_MASK) +#define ls1x_get_min(t) (((t) >> LS1X_MIN_OFFSET) & LS1X_MIN_MASK) +#define ls1x_get_hour(t) (((t) >> LS1X_HOUR_OFFSET) & LS1X_HOUR_MASK) +#define ls1x_get_day(t) (((t) >> LS1X_DAY_OFFSET) & LS1X_DAY_MASK) +#define ls1x_get_month(t) (((t) >> LS1X_MONTH_OFFSET) & LS1X_MONTH_MASK) + +#define RTC_CNTR_OK (SYS_CNTRL_E0 | SYS_CNTRL_32S) + +static int ls1x_rtc_read_time(struct device *dev, struct rtc_time *rtm) +{ + unsigned long v; + time64_t t; + + v = readl(SYS_TOYREAD0); + t = readl(SYS_TOYREAD1); + + memset(rtm, 0, sizeof(struct rtc_time)); + t = mktime64((t & LS1X_YEAR_MASK), ls1x_get_month(v), + ls1x_get_day(v), ls1x_get_hour(v), + ls1x_get_min(v), ls1x_get_sec(v)); + rtc_time64_to_tm(t, rtm); + + return 0; +} + +static int ls1x_rtc_set_time(struct device *dev, struct rtc_time *rtm) +{ + unsigned long v, t, c; + int ret = -ETIMEDOUT; + + v = ((rtm->tm_mon + 1) << LS1X_MONTH_OFFSET) + | (rtm->tm_mday << LS1X_DAY_OFFSET) + | (rtm->tm_hour << LS1X_HOUR_OFFSET) + | (rtm->tm_min << LS1X_MIN_OFFSET) + | (rtm->tm_sec << LS1X_SEC_OFFSET); + + writel(v, SYS_TOYWRITE0); + c = 0x10000; + /* add timeout check counter, for more safe */ + while ((readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TS) && --c) + usleep_range(1000, 3000); + + if (!c) { + dev_err(dev, "set time timeout!\n"); + goto err; + } + + t = rtm->tm_year + 1900; + writel(t, SYS_TOYWRITE1); + c = 0x10000; + while ((readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TS) && --c) + usleep_range(1000, 3000); + + if (!c) { + dev_err(dev, "set time timeout!\n"); + goto err; + } + return 0; +err: + return ret; +} + +static const struct rtc_class_ops ls1x_rtc_ops = { + .read_time = ls1x_rtc_read_time, + .set_time = ls1x_rtc_set_time, +}; + +static int ls1x_rtc_probe(struct platform_device *pdev) +{ + struct rtc_device *rtcdev; + unsigned long v; + + v = readl(SYS_COUNTER_CNTRL); + if (!(v & RTC_CNTR_OK)) { + dev_err(&pdev->dev, "rtc counters not working\n"); + return -ENODEV; + } + + /* set to 1 HZ if needed */ + if (readl(SYS_TOYTRIM) != 32767) { + v = 0x100000; + while ((readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TTS) && --v) + usleep_range(1000, 3000); + + if (!v) { + dev_err(&pdev->dev, "time out\n"); + return -ETIMEDOUT; + } + writel(32767, SYS_TOYTRIM); + } + /* this loop coundn't be endless */ + while (readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TTS) + usleep_range(1000, 3000); + + rtcdev = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtcdev)) + return PTR_ERR(rtcdev); + + platform_set_drvdata(pdev, rtcdev); + rtcdev->ops = &ls1x_rtc_ops; + rtcdev->range_min = RTC_TIMESTAMP_BEGIN_1900; + rtcdev->range_max = RTC_TIMESTAMP_END_2099; + + return devm_rtc_register_device(rtcdev); +} + +static struct platform_driver ls1x_rtc_driver = { + .driver = { + .name = "ls1x-rtc", + }, + .probe = ls1x_rtc_probe, +}; + +module_platform_driver(ls1x_rtc_driver); + +MODULE_AUTHOR("zhao zhang <zhzhl555@gmail.com>"); +MODULE_LICENSE("GPL"); |