[PATCH 0/2] Add support for two RTCs

[PATCH 0/2] Add support for two RTCs

[Michael Walle]

I'll soon post support for the Kontron SMARC-sAM67 u-boot support.
I'm still waiting for the linux device trees to be merged (in -next
right now) and then to be synced to the u-boot tree. That board
features two different RTCs and this will already support for these.

You can find the device tree at [1]. RTC nodes are in the overlays,
though there is none for the RV3032 at the moment.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/arch/arm64/boot/dts/ti/k3-am67a-kontron-sa67-base.dts

Michael Walle (2):
  drivers: rtc: add PCF85063 support
  drivers: rtc: add RV3032 support

 drivers/rtc/Kconfig    |  15 +++++
 drivers/rtc/Makefile   |   2 +
 drivers/rtc/pcf85063.c | 107 ++++++++++++++++++++++++++++++++++++
 drivers/rtc/rv3032.c   | 121 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 245 insertions(+)
 create mode 100644 drivers/rtc/pcf85063.c
 create mode 100644 drivers/rtc/rv3032.c

-- 
2.47.3

[PATCH 1/2] drivers: rtc: add PCF85063 support

[Michael Walle]

Add support for the Microcrystal RV8263 and compatible RTCs. The
driver's name was taken from linux. It should work with any NXP PCF85063
compatible RTCs. It was tested with a RV8263.

Signed-off-by: Michael Walle <mwalle@kernel.org>
---
 drivers/rtc/Kconfig    |   8 +++
 drivers/rtc/Makefile   |   1 +
 drivers/rtc/pcf85063.c | 107 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 116 insertions(+)
 create mode 100644 drivers/rtc/pcf85063.c

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index ed903999f06..2336f2e57c9 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -161,6 +161,14 @@ config RTC_MAX313XX
 	  - Temperature sensor
 	  - CLKOUT generation
 
+config RTC_PCF85063
+	tristate "Enable PCF85063 driver"
+	depends on DM_I2C
+	depends on DM_RTC
+	help
+	  If you say yes here you get support for the NXP PCF85063 RTC
+	  and compatible chips.
+
 config RTC_PCF8563
 	tristate "Philips PCF8563"
 	help
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index a4ede413cd1..9d84aa836a1 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_RTC_MC146818) += mc146818.o
 obj-$(CONFIG_MCFRTC) += mcfrtc.o
 obj-$(CONFIG_RTC_MV) += mvrtc.o
 obj-$(CONFIG_RTC_MXS) += mxsrtc.o
+obj-$(CONFIG_RTC_PCF85063) += pcf85063.o
 obj-$(CONFIG_RTC_PCF8563) += pcf8563.o
 obj-$(CONFIG_RTC_PCF2127) += pcf2127.o
 obj-$(CONFIG_RTC_PL031) += pl031.o
diff --git a/drivers/rtc/pcf85063.c b/drivers/rtc/pcf85063.c
new file mode 100644
index 00000000000..737d4547aca
--- /dev/null
+++ b/drivers/rtc/pcf85063.c
@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PCF85063 and compatible I2C RTC driver
+ *
+ * Copyright (c) 2025 Kontron Europe GmbH.
+ */
+
+#include <dm.h>
+#include <i2c.h>
+#include <rtc.h>
+#include <dm/device_compat.h>
+
+#define PCF85063_REG_CTRL1		0x00 /* status */
+#define PCF85063_REG_CTRL1_SR		0x58
+
+#define PCF85063_REG_SC			0x04 /* datetime */
+#define PCF85063_REG_SC_OS		0x80
+
+static int pcf85063_get_time(struct udevice *dev, struct rtc_time *tm)
+{
+	u8 regs[7];
+	int ret;
+
+	ret = dm_i2c_read(dev, PCF85063_REG_SC, regs, sizeof(regs));
+	if (ret)
+		return ret;
+
+	if (regs[0] & PCF85063_REG_SC_OS) {
+		dev_err(dev, "Power loss detected, Invalid time\n");
+		return -EINVAL;
+	}
+
+	tm->tm_sec = bcd2bin(regs[0] & 0x7f);
+	tm->tm_min = bcd2bin(regs[1] & 0x7f);
+	tm->tm_hour = bcd2bin(regs[2] & 0x3f);
+	tm->tm_mday = bcd2bin(regs[3] & 0x3f);
+	tm->tm_wday = regs[4] & 0x07;
+	tm->tm_mon = bcd2bin(regs[5] & 0x1f) - 1;
+	tm->tm_year = bcd2bin(regs[6]) + 2000;
+
+	return 0;
+}
+
+static int pcf85063_set_time(struct udevice *dev, const struct rtc_time *tm)
+{
+	u8 regs[7];
+
+	if (tm->tm_year < 2000 || tm->tm_year > 2099) {
+		dev_err(dev, "Year must be between 2000 and 2099.\n");
+		return -EINVAL;
+	}
+
+	regs[0] = bin2bcd(tm->tm_sec);
+	regs[1] = bin2bcd(tm->tm_min);
+	regs[2] = bin2bcd(tm->tm_hour);
+	regs[3] = bin2bcd(tm->tm_mday);
+	regs[4] = tm->tm_wday;
+	regs[5] = bin2bcd(tm->tm_mon + 1);
+	regs[6] = bin2bcd(tm->tm_year % 100);
+
+	return dm_i2c_write(dev, PCF85063_REG_SC, regs, sizeof(regs));
+}
+
+static int pcf85063_reset(struct udevice *dev)
+{
+	return dm_i2c_reg_write(dev, PCF85063_REG_CTRL1, PCF85063_REG_CTRL1_SR);
+}
+
+static int pcf85063_read(struct udevice *dev, unsigned int offset, u8 *buf,
+			 unsigned int len)
+{
+	return dm_i2c_read(dev, offset, buf, len);
+}
+
+static int pcf85063_write(struct udevice *dev, unsigned int offset,
+			  const u8 *buf, unsigned int len)
+{
+	return dm_i2c_write(dev, offset, buf, len);
+}
+
+static const struct rtc_ops pcf85063_rtc_ops = {
+	.get = pcf85063_get_time,
+	.set = pcf85063_set_time,
+	.reset = pcf85063_reset,
+	.read = pcf85063_read,
+	.write = pcf85063_write,
+};
+
+static int pcf85063_probe(struct udevice *dev)
+{
+	i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS | DM_I2C_CHIP_WR_ADDRESS);
+
+	return 0;
+}
+
+static const struct udevice_id pcf85063_of_id[] = {
+	{ .compatible = "microcrystal,rv8263" },
+	{ }
+};
+
+U_BOOT_DRIVER(rtc_pcf85063) = {
+	.name	= "rtc-pcf85063",
+	.id     = UCLASS_RTC,
+	.probe  = pcf85063_probe,
+	.of_match = pcf85063_of_id,
+	.ops    = &pcf85063_rtc_ops,
+};
-- 
2.47.3

[PATCH 2/2] drivers: rtc: add RV3032 support

[Michael Walle]

Add support for the Microcrystal RV3032 RTC.

Signed-off-by: Michael Walle <mwalle@kernel.org>
---
 drivers/rtc/Kconfig  |   7 +++
 drivers/rtc/Makefile |   1 +
 drivers/rtc/rv3032.c | 121 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 129 insertions(+)
 create mode 100644 drivers/rtc/rv3032.c

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 2336f2e57c9..c6c6a02221a 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -194,6 +194,13 @@ config RTC_RV3029
 	  This driver supports reading and writing the RTC/calendar and the
 	  battery-baced SRAM section.
 
+config RTC_RV3032
+	bool "Enable RV3032 driver"
+	depends on DM_RTC
+	help
+	  If you say yes here you get support for the Micro Crystal RV3032
+	  RTC.
+
 config RTC_RV8803
 	bool "Enable RV8803 driver"
 	depends on DM_RTC
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 9d84aa836a1..9df373d5148 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -34,6 +34,7 @@ obj-$(CONFIG_RTC_PL031) += pl031.o
 obj-$(CONFIG_RTC_PT7C4338) += pt7c4338.o
 obj-$(CONFIG_RTC_RV3028) += rv3028.o
 obj-$(CONFIG_RTC_RV3029) += rv3029.o
+obj-$(CONFIG_RTC_RV3032) += rv3032.o
 obj-$(CONFIG_RTC_RV8803) += rv8803.o
 obj-$(CONFIG_RTC_RX8025) += rx8025.o
 obj-$(CONFIG_RTC_RX8010SJ) += rx8010sj.o
diff --git a/drivers/rtc/rv3032.c b/drivers/rtc/rv3032.c
new file mode 100644
index 00000000000..87ff5204e73
--- /dev/null
+++ b/drivers/rtc/rv3032.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Micro Crystal RV3032 I2C RTC driver
+ *
+ * Copyright (c) 2025 Kontron Europe GmbH.
+ */
+
+#include <dm.h>
+#include <i2c.h>
+#include <rtc.h>
+#include <dm/device_compat.h>
+
+#define RV3032_REG_SEC			0x01
+#define RV3032_REG_STATUS		0x0d
+#define RV3032_REG_STATUS_VLF		BIT(0)
+#define RV3032_REG_STATUS_PORF		BIT(1)
+
+static int rv3032_get_time(struct udevice *dev, struct rtc_time *tm)
+{
+	int ret, status;
+	u8 regs[7];
+
+	status = dm_i2c_reg_read(dev, RV3032_REG_STATUS);
+	if (status < 0)
+		return status;
+
+	if (status & (RV3032_REG_STATUS_PORF | RV3032_REG_STATUS_VLF)) {
+		dev_err(dev, "Power loss detected, Invalid time\n");
+		return -EINVAL;
+	}
+
+	ret = dm_i2c_read(dev, RV3032_REG_SEC, regs, sizeof(regs));
+	if (ret)
+		return ret;
+
+	tm->tm_sec = bcd2bin(regs[0] & 0x7f);
+	tm->tm_min = bcd2bin(regs[1] & 0x7f);
+	tm->tm_hour = bcd2bin(regs[2] & 0x3f);
+	tm->tm_mday = bcd2bin(regs[3] & 0x3f);
+	tm->tm_wday = regs[4] & 0x07;
+	tm->tm_mon = bcd2bin(regs[5] & 0x1f) - 1;
+	tm->tm_year = bcd2bin(regs[6]) + 2000;
+
+	return 0;
+}
+
+static int rv3032_set_time(struct udevice *dev, const struct rtc_time *tm)
+{
+	u8 regs[7];
+	int ret;
+
+	if (tm->tm_year < 2000 || tm->tm_year > 2099) {
+		dev_err(dev, "Year must be between 2000 and 2099.\n");
+		return -EINVAL;
+	}
+
+	regs[0] = bin2bcd(tm->tm_sec);
+	regs[1] = bin2bcd(tm->tm_min);
+	regs[2] = bin2bcd(tm->tm_hour);
+	regs[3] = bin2bcd(tm->tm_mday);
+	regs[4] = tm->tm_wday;
+	regs[5] = bin2bcd(tm->tm_mon + 1);
+	regs[6] = bin2bcd(tm->tm_year % 100);
+
+	ret = dm_i2c_write(dev, RV3032_REG_SEC, regs, sizeof(regs));
+	if (ret)
+		return ret;
+
+	return dm_i2c_reg_clrset(dev, RV3032_REG_STATUS,
+				 RV3032_REG_STATUS_PORF | RV3032_REG_STATUS_VLF,
+				 0);
+}
+
+static int rv3032_read(struct udevice *dev, unsigned int offset, u8 *buf,
+		       unsigned int len)
+{
+	return dm_i2c_read(dev, offset, buf, len);
+}
+
+static int rv3032_write(struct udevice *dev, unsigned int offset,
+			const u8 *buf, unsigned int len)
+{
+	return dm_i2c_write(dev, offset, buf, len);
+}
+
+static int rv3032_reset(struct udevice *dev)
+{
+	/*
+	 * There is no reset, but the "date reset" command needs this op to
+	 * actually set the default time
+	 */
+	return 0;
+}
+
+static const struct rtc_ops rv3032_rtc_ops = {
+	.get = rv3032_get_time,
+	.set = rv3032_set_time,
+	.read = rv3032_read,
+	.write = rv3032_write,
+	.reset = rv3032_reset,
+};
+
+static int rv3032_probe(struct udevice *dev)
+{
+	i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS | DM_I2C_CHIP_WR_ADDRESS);
+
+	return 0;
+}
+
+static const struct udevice_id rv3032_of_id[] = {
+	{ .compatible = "microcrystal,rv3032" },
+	{ }
+};
+
+U_BOOT_DRIVER(rtc_rv3032) = {
+	.name	= "rtc-rv3032",
+	.id     = UCLASS_RTC,
+	.probe  = rv3032_probe,
+	.of_match = rv3032_of_id,
+	.ops    = &rv3032_rtc_ops,
+};
-- 
2.47.3

Re: [PATCH 1/2] drivers: rtc: add PCF85063 support

[Tom Rini]

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On Fri, Nov 14, 2025 at 04:12:47PM +0100, Michael Walle wrote:

> Add support for the Microcrystal RV8263 and compatible RTCs. The
> driver's name was taken from linux. It should work with any NXP PCF85063
> compatible RTCs. It was tested with a RV8263.
> 
> Signed-off-by: Michael Walle <mwalle@kernel.org>
> ---
>  drivers/rtc/Kconfig    |   8 +++
>  drivers/rtc/Makefile   |   1 +
>  drivers/rtc/pcf85063.c | 107 +++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 116 insertions(+)
>  create mode 100644 drivers/rtc/pcf85063.c
> 
> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
> index ed903999f06..2336f2e57c9 100644
> --- a/drivers/rtc/Kconfig
> +++ b/drivers/rtc/Kconfig
> @@ -161,6 +161,14 @@ config RTC_MAX313XX
>  	  - Temperature sensor
>  	  - CLKOUT generation
>  
> +config RTC_PCF85063
> +	tristate "Enable PCF85063 driver"

tristate is wrong for U-Boot, only bool is meaningful (and I need to go
update checkpatch.pl to complain about this). This is I assume otherwise
checkpatch warning free and compiles on sandbox?

-- 
Tom

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Re: [PATCH 1/2] drivers: rtc: add PCF85063 support

[Michael Walle]

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>> +config RTC_PCF85063
>> +	tristate "Enable PCF85063 driver"
>
> tristate is wrong for U-Boot, only bool is meaningful (and I need to go
> update checkpatch.pl to complain about this).

Yeah, sorry, This was a copy and paste error from the very next
config entry. I'll fix it in v2 and add a patch to convert the
existing tristate to bool.

> This is I assume otherwise
> checkpatch warning free and compiles on sandbox?

Yeah, except for the missing maintainers entry.

-michael

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Re: [PATCH 1/2] drivers: rtc: add PCF85063 support

[Tom Rini]

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On Mon, Nov 17, 2025 at 09:13:36AM +0100, Michael Walle wrote:
> >> +config RTC_PCF85063
> >> +	tristate "Enable PCF85063 driver"
> >
> > tristate is wrong for U-Boot, only bool is meaningful (and I need to go
> > update checkpatch.pl to complain about this).
> 
> Yeah, sorry, This was a copy and paste error from the very next
> config entry. I'll fix it in v2 and add a patch to convert the
> existing tristate to bool.
> 
> > This is I assume otherwise
> > checkpatch warning free and compiles on sandbox?
> 
> Yeah, except for the missing maintainers entry.

OK, thanks!

-- 
Tom

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