[PATCH v2 0/6] rtc: ls2x: Add support for the Loongson-2K/LS7A RTC

It has been a while since v1 of this series was sent (2020-09);
apparently, I did not have enough time or resource figuring out the exact
difference between rtc-ls1x and rtc-ls2x to see if the two can in fact be
merged, even today. Sorry for the long delay!

According to the manuals, though, the initialization sequence and
bitfield descriptions look certainly different, so I'm a bit wary about
just going ahead and merging these. Per Tiezhu's suggestion in the
previous thread, I'm just re-submitting this series with tags collected
and Huacai's e-mail address updated. If anyone (probably Loongson guys?)
could provide more information regarding the possible merger of rtc-ls1x
and rtc-ls2x, that would be great.

This patch series adds support for the RTC module found on various
Loongson systems with the Loongson-2K SoC or the LS7A bridge chip.
The driver is rewritten from an out-of-tree version to meet mainline
standards. I write kernel code as a hobby, though, so there might still
be overlooked issues. Any suggestions are welcome.

Note that, the Loongson-2K platform was upstreamed after v1 of this
series, so v2 additionally contains enablement for it. I'm unable to
test with my 2K board now, however, so Loongson guys, please test this
series again on your collection of LS7A and 2K systems, thanks!

v2:
- Rebased on top of latest linux-next
- Updated Huacai's e-mail address to the kernel.org one
- Added collected tags
- Added adaptation for newly upstreamed Loongson-2K platforms

WANG Xuerui (6):
  rtc: ls2x: Add support for the Loongson-2K/LS7A RTC
  dt-bindings: rtc: Add bindings for LS2X RTC
  MIPS: Loongson64: DTS: Add RTC support to LS7A
  MIPS: Loongson: Enable LS2X RTC in loongson3_defconfig
  MIPS: Loongson64: DTS: Add RTC support to Loongson-2K
  MIPS: Loongson: Enable LS2X RTC in loongson2k_defconfig

 .../devicetree/bindings/rtc/trivial-rtc.yaml  |   2 +
 .../boot/dts/loongson/loongson64-2k1000.dtsi  |   5 +
 arch/mips/boot/dts/loongson/ls7a-pch.dtsi     |   5 +
 arch/mips/configs/loongson2k_defconfig        |   1 +
 arch/mips/configs/loongson3_defconfig         |   1 +
 drivers/rtc/Kconfig                           |  11 +
 drivers/rtc/Makefile                          |   1 +
 drivers/rtc/rtc-ls2x.c                        | 225 ++++++++++++++++++
 8 files changed, 251 insertions(+)
 create mode 100644 drivers/rtc/rtc-ls2x.c

-- 
2.30.1

The Loongson-2K RTC module is now supported, enable it.

The MMIO address is unclear from the Loongson 2K1000 user manual, I took
it from Loongson's out-of-tree fork of Linux 4.19.

Signed-off-by: WANG Xuerui <redacted>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
---
 arch/mips/boot/dts/loongson/loongson64-2k1000.dtsi | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/mips/boot/dts/loongson/loongson64-2k1000.dtsi b/arch/mips/boot/dts/loongson/loongson64-2k1000.dtsi
index 569e814def83..0f00080f77b9 100644
--- a/arch/mips/boot/dts/loongson/loongson64-2k1000.dtsi
+++ b/arch/mips/boot/dts/loongson/loongson64-2k1000.dtsi

@@ -52,6 +52,11 @@ package0: bus@10000000 {
 			0 0x40000000 0 0x40000000 0 0x40000000
 			0xfe 0x00000000 0xfe 0x00000000 0 0x40000000>;
 
+		rtc0: rtc@1fe07800 {
+			compatible = "loongson,ls2x-rtc";
+			reg = <0 0x1fe07800 0 0x78>;
+		};
+
 		liointc0: interrupt-controller@1fe11400 {
 			compatible = "loongson,liointc-2.0";
 			reg = <0 0x1fe11400 0 0x40>,

-- 
2.30.1

This is now supported, enable for Loongson-3 systems.
Other systems are unaffected.

Signed-off-by: WANG Xuerui <redacted>
---
 arch/mips/configs/loongson3_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/mips/configs/loongson3_defconfig b/arch/mips/configs/loongson3_defconfig
index a18609cf0e5e..b34ca534b9b6 100644
--- a/arch/mips/configs/loongson3_defconfig
+++ b/arch/mips/configs/loongson3_defconfig

@@ -325,6 +325,7 @@ CONFIG_USB_SERIAL_OPTION=m
 CONFIG_RTC_CLASS=y
 CONFIG_RTC_DRV_CMOS=y
 CONFIG_RTC_DRV_GOLDFISH=y
+CONFIG_RTC_DRV_LS2X=y
 CONFIG_DMADEVICES=y
 CONFIG_VIRTIO_PCI=y
 CONFIG_VIRTIO_BALLOON=m

-- 
2.30.1

Document the binding for the LS2X RTC block found on the Loongson-2K SoC
and the LS7A bridge, originally appearing on the Loongson-2H.

Signed-off-by: WANG Xuerui <redacted>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
---
 Documentation/devicetree/bindings/rtc/trivial-rtc.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/rtc/trivial-rtc.yaml b/Documentation/devicetree/bindings/rtc/trivial-rtc.yaml
index 7548d8714871..568aa89989fe 100644
--- a/Documentation/devicetree/bindings/rtc/trivial-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/trivial-rtc.yaml

@@ -42,6 +42,8 @@ properties:
       - isil,isl1218
       # Intersil ISL12022 Real-time Clock
       - isil,isl12022
+      # Loongson LS2X RTC
+      - loongson,ls2x-rtc
       # Real Time Clock Module with I2C-Bus
       - microcrystal,rv3028
       # Real Time Clock Module with I2C-Bus

-- 
2.30.1

This is now supported, enable for Loongson-2K systems.
Other systems are unaffected.

Signed-off-by: WANG Xuerui <redacted>
---
 arch/mips/configs/loongson2k_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/mips/configs/loongson2k_defconfig b/arch/mips/configs/loongson2k_defconfig
index e948ca487e2d..e15f34857956 100644
--- a/arch/mips/configs/loongson2k_defconfig
+++ b/arch/mips/configs/loongson2k_defconfig

@@ -280,6 +280,7 @@ CONFIG_USB_SERIAL=m
 CONFIG_USB_SERIAL_OPTION=m
 CONFIG_RTC_CLASS=y
 CONFIG_RTC_DRV_CMOS=y
+CONFIG_RTC_DRV_LS2X=y
 CONFIG_DMADEVICES=y
 # CONFIG_CPU_HWMON is not set
 CONFIG_PM_DEVFREQ=y

-- 
2.30.1

The LS7A RTC module is now supported, enable it.

Signed-off-by: WANG Xuerui <redacted>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
---
 arch/mips/boot/dts/loongson/ls7a-pch.dtsi | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/mips/boot/dts/loongson/ls7a-pch.dtsi b/arch/mips/boot/dts/loongson/ls7a-pch.dtsi
index f99a7a11fded..39808e97e6e1 100644
--- a/arch/mips/boot/dts/loongson/ls7a-pch.dtsi
+++ b/arch/mips/boot/dts/loongson/ls7a-pch.dtsi

@@ -19,6 +19,11 @@ pic: interrupt-controller@10000000 {
 			#interrupt-cells = <2>;
 		};
 
+		rtc0: rtc@100d0100 {
+			compatible = "loongson,ls2x-rtc";
+			reg = <0 0x100d0100 0 0x78>;
+		};
+
 		ls7a_uart0: serial@10080000 {
 			compatible = "ns16550a";
 			reg = <0 0x10080000 0 0x100>;

-- 
2.30.1

This RTC module is integrated into the Loongson-2K SoC and the LS7A
bridge chip. This version is almost entirely rewritten to make use of
current kernel API.

Signed-off-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: WANG Xuerui <redacted>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
---
 drivers/rtc/Kconfig    |  11 ++
 drivers/rtc/Makefile   |   1 +
 drivers/rtc/rtc-ls2x.c | 225 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 237 insertions(+)
 create mode 100644 drivers/rtc/rtc-ls2x.c

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index d8c13fded164..55beede68829 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig

@@ -1304,6 +1304,17 @@ 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 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 2dd0dd956b0e..6042ff1e73b7 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile

@@ -81,6 +81,7 @@ 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..8eddb0316b3b
--- /dev/null
+++ b/drivers/rtc/rtc-ls2x.c

@@ -0,0 +1,225 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Loongson-2K/7A RTC driver
+ *
+ * Based on the 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/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+#include <linux/spinlock.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_MON_SHIFT  26
+#define TOY_DAY        GENMASK(25, 21)
+#define TOY_DAY_SHIFT  21
+#define TOY_HOUR       GENMASK(20, 16)
+#define TOY_HOUR_SHIFT 16
+#define TOY_MIN        GENMASK(15, 10)
+#define TOY_MIN_SHIFT  10
+#define TOY_SEC        GENMASK(9, 4)
+#define TOY_SEC_SHIFT  4
+#define TOY_MSEC       GENMASK(3, 0)
+#define TOY_MSEC_SHIFT 0
+
+struct ls2x_rtc_priv {
+	struct regmap *regmap;
+	spinlock_t lock;
+};
+
+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 = (regs->reg0 & TOY_SEC) >> TOY_SEC_SHIFT;
+	tm->tm_min = (regs->reg0 & TOY_MIN) >> TOY_MIN_SHIFT;
+	tm->tm_hour = (regs->reg0 & TOY_HOUR) >> TOY_HOUR_SHIFT;
+	tm->tm_mday = (regs->reg0 & TOY_DAY) >> TOY_DAY_SHIFT;
+	tm->tm_mon = ((regs->reg0 & TOY_MON) >> TOY_MON_SHIFT) - 1;
+}
+
+static inline void ls2x_rtc_time_to_regs(struct rtc_time *tm,
+					 struct ls2x_rtc_regs *regs)
+{
+	regs->reg0 = (tm->tm_sec << TOY_SEC_SHIFT) & TOY_SEC;
+	regs->reg0 |= (tm->tm_min << TOY_MIN_SHIFT) & TOY_MIN;
+	regs->reg0 |= (tm->tm_hour << TOY_HOUR_SHIFT) & TOY_HOUR;
+	regs->reg0 |= (tm->tm_mday << TOY_DAY_SHIFT) & TOY_DAY;
+	regs->reg0 |= ((tm->tm_mon + 1) << TOY_MON_SHIFT) & TOY_MON;
+	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;
+
+	spin_lock_irq(&priv->lock);
+
+	ret = regmap_read(priv->regmap, TOY_READ1_REG, &regs.reg1);
+	if (unlikely(ret)) {
+		dev_err(dev, "Failed to read time: %d\n", ret);
+		goto fail;
+	}
+
+	ret = regmap_read(priv->regmap, TOY_READ0_REG, &regs.reg0);
+	if (unlikely(ret)) {
+		dev_err(dev, "Failed to read time: %d\n", ret);
+		goto fail;
+	}
+
+	spin_unlock_irq(&priv->lock);
+
+	ls2x_rtc_regs_to_time(&regs, tm);
+
+	return 0;
+
+fail:
+	spin_unlock_irq(&priv->lock);
+	return ret;
+}
+
+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);
+
+	spin_lock_irq(&priv->lock);
+
+	ret = regmap_write(priv->regmap, TOY_WRITE0_REG, regs.reg0);
+	if (unlikely(ret)) {
+		dev_err(dev, "Failed to set time: %d\n", ret);
+		goto fail;
+	}
+
+	ret = regmap_write(priv->regmap, TOY_WRITE1_REG, regs.reg1);
+	if (unlikely(ret)) {
+		dev_err(dev, "Failed to set time: %d\n", ret);
+		goto fail;
+	}
+
+	spin_unlock_irq(&priv->lock);
+
+	return 0;
+
+fail:
+	spin_unlock_irq(&priv->lock);
+	return ret;
+}
+
+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;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (unlikely(!priv))
+		return -ENOMEM;
+
+	spin_lock_init(&priv->lock);
+	platform_set_drvdata(pdev, priv);
+
+	regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(regs)) {
+		ret = PTR_ERR(regs);
+		dev_err(dev, "Failed to map rtc registers: %d\n", ret);
+		return ret;
+	}
+
+	priv->regmap = devm_regmap_init_mmio(dev, regs,
+					     &ls2x_rtc_regmap_config);
+	if (IS_ERR(priv->regmap)) {
+		ret = PTR_ERR(priv->regmap);
+		dev_err(dev, "Failed to init regmap: %d\n", ret);
+		return ret;
+	}
+
+	rtc = devm_rtc_allocate_device(dev);
+	if (IS_ERR(rtc)) {
+		ret = PTR_ERR(rtc);
+		dev_err(dev, "Failed to allocate rtc device: %d\n", ret);
+		return ret;
+	}
+
+	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 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 = of_match_ptr(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");

-- 
2.30.1

Hi WANG,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on next-20210505]
[cannot apply to abelloni/rtc-next robh/for-next v5.12]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/WANG-Xuerui/rtc-ls2x-Add-support-for-the-Loongson-2K-LS7A-RTC/20210506-013703
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git d665ea6ea86c785760ee4bad4543dab3267ad074
config: parisc-allyesconfig (attached as .config)
compiler: hppa-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/a4a12242f17c2ad92025b724458a31eb088e1893
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review WANG-Xuerui/rtc-ls2x-Add-support-for-the-Loongson-2K-LS7A-RTC/20210506-013703
        git checkout a4a12242f17c2ad92025b724458a31eb088e1893
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross W=1 ARCH=parisc 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All warnings (new ones prefixed by >>):

   drivers/rtc/rtc-ls2x.c: In function 'ls2x_rtc_probe':
   drivers/rtc/rtc-ls2x.c:202:9: error: implicit declaration of function 'rtc_register_device'; did you mean 'devm_rtc_register_device'? [-Werror=implicit-function-declaration]
     202 |  return rtc_register_device(rtc);
         |         ^~~~~~~~~~~~~~~~~~~
         |         devm_rtc_register_device
   drivers/rtc/rtc-ls2x.c: At top level:
   drivers/rtc/rtc-ls2x.c:215:21: error: implicit declaration of function 'of_match_ptr' [-Werror=implicit-function-declaration]
     215 |   .of_match_table = of_match_ptr(ls2x_rtc_of_match),
         |                     ^~~~~~~~~~~~

quoted

drivers/rtc/rtc-ls2x.c:215:21: warning: initialization of 'const struct of_device_id *' from 'int' makes pointer from integer without a cast [-Wint-conversion]

   drivers/rtc/rtc-ls2x.c:215:21: note: (near initialization for 'ls2x_rtc_driver.driver.of_match_table')
   drivers/rtc/rtc-ls2x.c:215:21: error: initializer element is not constant
   drivers/rtc/rtc-ls2x.c:215:21: note: (near initialization for 'ls2x_rtc_driver.driver.of_match_table')
   cc1: some warnings being treated as errors


vim +215 drivers/rtc/rtc-ls2x.c

   210	
   211	static struct platform_driver ls2x_rtc_driver = {
   212		.probe		= ls2x_rtc_probe,
   213		.driver		= {
   214			.name	= "ls2x-rtc",
 > 215			.of_match_table = of_match_ptr(ls2x_rtc_of_match),
   216		},
   217	};
   218	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

Hi WANG,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on next-20210505]
[cannot apply to abelloni/rtc-next robh/for-next v5.12]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/WANG-Xuerui/rtc-ls2x-Add-support-for-the-Loongson-2K-LS7A-RTC/20210506-013703
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git d665ea6ea86c785760ee4bad4543dab3267ad074
config: arc-allyesconfig (attached as .config)
compiler: arceb-elf-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/a4a12242f17c2ad92025b724458a31eb088e1893
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review WANG-Xuerui/rtc-ls2x-Add-support-for-the-Loongson-2K-LS7A-RTC/20210506-013703
        git checkout a4a12242f17c2ad92025b724458a31eb088e1893
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross W=1 ARCH=arc 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All errors (new ones prefixed by >>):

   drivers/rtc/rtc-ls2x.c: In function 'ls2x_rtc_probe':

quoted

drivers/rtc/rtc-ls2x.c:202:9: error: implicit declaration of function 'rtc_register_device'; did you mean 'devm_rtc_register_device'? [-Werror=implicit-function-declaration]

     202 |  return rtc_register_device(rtc);
         |         ^~~~~~~~~~~~~~~~~~~
         |         devm_rtc_register_device
   drivers/rtc/rtc-ls2x.c: At top level:

quoted

drivers/rtc/rtc-ls2x.c:205:34: error: array type has incomplete element type 'struct of_device_id'

     205 | static const struct of_device_id ls2x_rtc_of_match[] = {
         |                                  ^~~~~~~~~~~~~~~~~

quoted

drivers/rtc/rtc-ls2x.c:206:4: error: field name not in record or union initializer

     206 |  { .compatible = "loongson,ls2x-rtc" },
         |    ^
   drivers/rtc/rtc-ls2x.c:206:4: note: (near initialization for 'ls2x_rtc_of_match')

quoted

drivers/rtc/rtc-ls2x.c:215:21: error: implicit declaration of function 'of_match_ptr' [-Werror=implicit-function-declaration]

     215 |   .of_match_table = of_match_ptr(ls2x_rtc_of_match),
         |                     ^~~~~~~~~~~~
   drivers/rtc/rtc-ls2x.c:205:34: warning: 'ls2x_rtc_of_match' defined but not used [-Wunused-variable]
     205 | static const struct of_device_id ls2x_rtc_of_match[] = {
         |                                  ^~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +202 drivers/rtc/rtc-ls2x.c

   152	
   153	static int ls2x_rtc_probe(struct platform_device *pdev)
   154	{
   155		struct device *dev = &pdev->dev;
   156		struct rtc_device *rtc;
   157		struct ls2x_rtc_priv *priv;
   158		void __iomem *regs;
   159		int ret;
   160	
   161		priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
   162		if (unlikely(!priv))
   163			return -ENOMEM;
   164	
   165		spin_lock_init(&priv->lock);
   166		platform_set_drvdata(pdev, priv);
   167	
   168		regs = devm_platform_ioremap_resource(pdev, 0);
   169		if (IS_ERR(regs)) {
   170			ret = PTR_ERR(regs);
   171			dev_err(dev, "Failed to map rtc registers: %d\n", ret);
   172			return ret;
   173		}
   174	
   175		priv->regmap = devm_regmap_init_mmio(dev, regs,
   176						     &ls2x_rtc_regmap_config);
   177		if (IS_ERR(priv->regmap)) {
   178			ret = PTR_ERR(priv->regmap);
   179			dev_err(dev, "Failed to init regmap: %d\n", ret);
   180			return ret;
   181		}
   182	
   183		rtc = devm_rtc_allocate_device(dev);
   184		if (IS_ERR(rtc)) {
   185			ret = PTR_ERR(rtc);
   186			dev_err(dev, "Failed to allocate rtc device: %d\n", ret);
   187			return ret;
   188		}
   189	
   190		rtc->ops = &ls2x_rtc_ops;
   191	
   192		/* Due to hardware erratum, all years multiple of 4 are considered
   193		 * leap year, so only years 2000 through 2099 are usable.
   194		 *
   195		 * Previous out-of-tree versions of this driver wrote tm_year directly
   196		 * into the year register, so epoch 2000 must be used to preserve
   197		 * semantics on shipped systems.
   198		 */
   199		rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
   200		rtc->range_max = RTC_TIMESTAMP_END_2099;
   201	
 > 202		return rtc_register_device(rtc);
   203	}
   204	
 > 205	static const struct of_device_id ls2x_rtc_of_match[] = {
 > 206		{ .compatible = "loongson,ls2x-rtc" },
   207		{ /* sentinel */ },
   208	};
   209	MODULE_DEVICE_TABLE(of, ls2x_rtc_of_match);
   210	
   211	static struct platform_driver ls2x_rtc_driver = {
   212		.probe		= ls2x_rtc_probe,
   213		.driver		= {
   214			.name	= "ls2x-rtc",
 > 215			.of_match_table = of_match_ptr(ls2x_rtc_of_match),
   216		},
   217	};
   218	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

Sorry for the noise, there's one compile error not caught after rebase. 
It was late in the night and I didn't watch the test compile finish 
before sending the series.

Will resend very soon. (/me yawns)

On 5/6/21 00:39, WANG Xuerui wrote: