diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index daff06707455..819f366b4d91 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig

@@ -1313,6 +1313,17 @@ config RTC_DRV_NTXEC
          embedded controller found in certain e-book readers designed by the
          original design manufacturer Netronix.

+config RTC_DRV_LS2X
+       tristate "Loongson LS2X RTC"
+       depends on OF && MACH_LOONGSON64 || COMPILE_TEST
+       select REGMAP_MMIO
+       help
+         If you say yes here you get support for the RTC on the Loongson-2K
+         SoC and LS7A bridge, which first appeared on the Loongson-2H.
+
+         This driver can also be built as a module. If so, the module
+         will be called rtc-ls2x.
+
 comment "on-CPU RTC drivers"

 config RTC_DRV_ASM9260

diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 5ceeafe4d5b2..98e68484f519 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile

@@ -83,6 +83,7 @@ obj-$(CONFIG_RTC_DRV_LOONGSON1)       += rtc-ls1x.o
 obj-$(CONFIG_RTC_DRV_LP8788)   += rtc-lp8788.o
 obj-$(CONFIG_RTC_DRV_LPC24XX)  += rtc-lpc24xx.o
 obj-$(CONFIG_RTC_DRV_LPC32XX)  += rtc-lpc32xx.o
+obj-$(CONFIG_RTC_DRV_LS2X)     += rtc-ls2x.o
 obj-$(CONFIG_RTC_DRV_M41T80)   += rtc-m41t80.o
 obj-$(CONFIG_RTC_DRV_M41T93)   += rtc-m41t93.o
 obj-$(CONFIG_RTC_DRV_M41T94)   += rtc-m41t94.o

diff --git a/drivers/rtc/rtc-ls2x.c b/drivers/rtc/rtc-ls2x.c
new file mode 100644
index 000000000000..58901323b219
--- /dev/null
+++ b/drivers/rtc/rtc-ls2x.c

@@ -0,0 +1,180 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Loongson-2K/7A RTC driver
+ *
+ * Based on the original out-of-tree Loongson-2H RTC driver for Linux 2.6.32,
+ * by Shaozong Liu <liushaozong@loongson.cn>.
+ *
+ * Maintained out-of-tree by Huacai Chen <chenhuacai@kernel.org>.
+ *
+ * Rewritten for mainline by WANG Xuerui <git@xen0n.name>.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+
+#define TOY_TRIM_REG   0x20
+#define TOY_WRITE0_REG 0x24
+#define TOY_WRITE1_REG 0x28
+#define TOY_READ0_REG  0x2c
+#define TOY_READ1_REG  0x30
+#define TOY_MATCH0_REG 0x34
+#define TOY_MATCH1_REG 0x38
+#define TOY_MATCH2_REG 0x3c
+#define RTC_CTRL_REG   0x40
+#define RTC_TRIM_REG   0x60
+#define RTC_WRITE0_REG 0x64
+#define RTC_READ0_REG  0x68
+#define RTC_MATCH0_REG 0x6c
+#define RTC_MATCH1_REG 0x70
+#define RTC_MATCH2_REG 0x74
+
+#define TOY_MON        GENMASK(31, 26)
+#define TOY_DAY        GENMASK(25, 21)
+#define TOY_HOUR       GENMASK(20, 16)
+#define TOY_MIN        GENMASK(15, 10)
+#define TOY_SEC        GENMASK(9, 4)
+#define TOY_MSEC       GENMASK(3, 0)
+
+struct ls2x_rtc_priv {
+       struct regmap *regmap;
+};
+
+static const struct regmap_config ls2x_rtc_regmap_config = {
+       .reg_bits = 32,
+       .val_bits = 32,
+       .reg_stride = 4,
+};
+
+struct ls2x_rtc_regs {
+       u32 reg0;
+       u32 reg1;
+};
+
+static inline void ls2x_rtc_regs_to_time(struct ls2x_rtc_regs *regs,
+                                        struct rtc_time *tm)
+{
+       tm->tm_year = regs->reg1;
+       tm->tm_sec = FIELD_GET(TOY_SEC, regs->reg0);
+       tm->tm_min = FIELD_GET(TOY_MIN, regs->reg0);
+       tm->tm_hour = FIELD_GET(TOY_HOUR, regs->reg0);
+       tm->tm_mday = FIELD_GET(TOY_DAY, regs->reg0);
+       tm->tm_mon = FIELD_GET(TOY_MON, regs->reg0) - 1;
+}
+
+static inline void ls2x_rtc_time_to_regs(struct rtc_time *tm,
+                                        struct ls2x_rtc_regs *regs)
+{
+       regs->reg0 = FIELD_PREP(TOY_SEC, tm->tm_sec);
+       regs->reg0 |= FIELD_PREP(TOY_MIN, tm->tm_min);
+       regs->reg0 |= FIELD_PREP(TOY_HOUR, tm->tm_hour);
+       regs->reg0 |= FIELD_PREP(TOY_DAY, tm->tm_mday);
+       regs->reg0 |= FIELD_PREP(TOY_MON, tm->tm_mon + 1);
+       regs->reg1 = tm->tm_year;
+}
+
+static int ls2x_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+       struct ls2x_rtc_priv *priv = dev_get_drvdata(dev);
+       struct ls2x_rtc_regs regs;
+       int ret;
+
+       ret = regmap_read(priv->regmap, TOY_READ1_REG, &regs.reg1);
+       if (unlikely(ret))
+               return ret;
+
+       ret = regmap_read(priv->regmap, TOY_READ0_REG, &regs.reg0);
+       if (unlikely(ret))
+               return ret;
+
+       ls2x_rtc_regs_to_time(&regs, tm);
+
+       return 0;
+}
+
+static int ls2x_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+       struct ls2x_rtc_priv *priv = dev_get_drvdata(dev);
+       struct ls2x_rtc_regs regs;
+       int ret;
+
+       ls2x_rtc_time_to_regs(tm, &regs);
+
+       ret = regmap_write(priv->regmap, TOY_WRITE0_REG, regs.reg0);
+       if (unlikely(ret))
+               return ret;
+
+       return regmap_write(priv->regmap, TOY_WRITE1_REG, regs.reg1);
+}
+
+static struct rtc_class_ops ls2x_rtc_ops = {
+       .read_time = ls2x_rtc_read_time,
+       .set_time = ls2x_rtc_set_time,
+};
+
+static int ls2x_rtc_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct rtc_device *rtc;
+       struct ls2x_rtc_priv *priv;
+       void __iomem *regs;
+
+       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+       if (unlikely(!priv))
+               return -ENOMEM;
+
+       platform_set_drvdata(pdev, priv);
+
+       regs = devm_platform_ioremap_resource(pdev, 0);
+       if (IS_ERR(regs))
+               return PTR_ERR(regs);
+
+       priv->regmap = devm_regmap_init_mmio(dev, regs,
+                                            &ls2x_rtc_regmap_config);
+       if (IS_ERR(priv->regmap))
+               return PTR_ERR(priv->regmap);
+
+       rtc = devm_rtc_allocate_device(dev);
+       if (IS_ERR(rtc))
+               return PTR_ERR(rtc);
+
+       rtc->ops = &ls2x_rtc_ops;
+
+       /* Due to hardware erratum, all years multiple of 4 are considered
+        * leap year, so only years 2000 through 2099 are usable.
+        *
+        * Previous out-of-tree versions of this driver wrote tm_year directly
+        * into the year register, so epoch 2000 must be used to preserve
+        * semantics on shipped systems.
+        */
+       rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+       rtc->range_max = RTC_TIMESTAMP_END_2099;
+
+       return devm_rtc_register_device(rtc);
+}
+
+static const struct of_device_id ls2x_rtc_of_match[] = {
+       { .compatible = "loongson,ls2x-rtc" },
+       { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, ls2x_rtc_of_match);
+
+static struct platform_driver ls2x_rtc_driver = {
+       .probe          = ls2x_rtc_probe,
+       .driver         = {
+               .name   = "ls2x-rtc",
+               .of_match_table = ls2x_rtc_of_match,
+       },
+};
+
+module_platform_driver(ls2x_rtc_driver);
+
+MODULE_DESCRIPTION("LS2X RTC driver");
+MODULE_AUTHOR("WANG Xuerui");
+MODULE_AUTHOR("Huacai Chen");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ls2x-rtc");
--

2.33.0