[PATCH v2 2/2] hwspinlock: Add StarFive hwspinlock device

[Xingyu Wu <xingyu.wu@starfivetech.com>]

Add support of hardware spinlock for the StarFive JHB100 SoC.
The hwspinlock provides 16 channels for using by secur core and AP core.

Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
---
 MAINTAINERS                              |   6 ++
 drivers/hwspinlock/Kconfig               |   8 ++
 drivers/hwspinlock/Makefile              |   1 +
 drivers/hwspinlock/starfive_hwspinlock.c | 130 +++++++++++++++++++++++
 4 files changed, 145 insertions(+)
 create mode 100644 drivers/hwspinlock/starfive_hwspinlock.c

diff --git a/MAINTAINERS b/MAINTAINERS
index c3fe46d7c4bc..4ff12806ba09 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -25275,6 +25275,12 @@ F:	Documentation/devicetree/bindings/power/starfive*
 F:	drivers/pmdomain/starfive/
 F:	include/dt-bindings/power/starfive,jh7110-pmu.h
 
+STARFIVE JHB100 HARDWARE SPINLOCK DRIVER
+M:      Xingyu Wu <xingyu.wu@starfivetech.com>
+S:      Supported
+F:      Documentation/devicetree/bindings/hwlock/starfive,jhb100-hwspinlock.yaml
+F:      drivers/hwspinlock/starfive_hwspinlock.c
+
 STARFIVE SOC DRIVERS
 M:	Conor Dooley <conor@kernel.org>
 S:	Maintained
diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig
index 3874d15b0e9b..797f5a833547 100644
--- a/drivers/hwspinlock/Kconfig
+++ b/drivers/hwspinlock/Kconfig
@@ -36,6 +36,14 @@ config HWSPINLOCK_SPRD
 
 	  If unsure, say N.
 
+config HWSPINLOCK_STARFIVE
+	tristate "StarFive Hardware Spinlock device"
+	depends on ARCH_STARFIVE || COMPILE_TEST
+	help
+	  Say y here to support the StarFive Hardware Spinlock device.
+
+	  If unsure, say N.
+
 config HWSPINLOCK_STM32
 	tristate "STM32 Hardware Spinlock device"
 	depends on MACH_STM32MP157 || COMPILE_TEST
diff --git a/drivers/hwspinlock/Makefile b/drivers/hwspinlock/Makefile
index a0f16c9aaa82..bc713bdc7e04 100644
--- a/drivers/hwspinlock/Makefile
+++ b/drivers/hwspinlock/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_HWSPINLOCK)		+= hwspinlock_core.o
 obj-$(CONFIG_HWSPINLOCK_OMAP)		+= omap_hwspinlock.o
 obj-$(CONFIG_HWSPINLOCK_QCOM)		+= qcom_hwspinlock.o
 obj-$(CONFIG_HWSPINLOCK_SPRD)		+= sprd_hwspinlock.o
+obj-$(CONFIG_HWSPINLOCK_STARFIVE)       += starfive_hwspinlock.o
 obj-$(CONFIG_HWSPINLOCK_STM32)		+= stm32_hwspinlock.o
 obj-$(CONFIG_HWSPINLOCK_SUN6I)		+= sun6i_hwspinlock.o
 obj-$(CONFIG_HSEM_U8500)		+= u8500_hsem.o
diff --git a/drivers/hwspinlock/starfive_hwspinlock.c b/drivers/hwspinlock/starfive_hwspinlock.c
new file mode 100644
index 000000000000..d85f43a48013
--- /dev/null
+++ b/drivers/hwspinlock/starfive_hwspinlock.c
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Hardware spinlock driver for StarFive JHB100 SoC
+ *
+ * Copyright (C) 2026 StarFive Technology Co., Ltd.
+ */
+
+#include <linux/delay.h>
+#include <linux/hwspinlock.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+#include "hwspinlock_internal.h"
+
+/* reg offset */
+#define STARFIVE_REG_APP_LOCK_REQ		0x08
+#define STARFIVE_REG_APP_LOCK_RLS		0x0C
+#define STARFIVE_REG_LOCK_STA			0x10
+
+/* macro STARFIVE_REG_LOCK_STA reg*/
+#define STARFIVE_STA_APP_OWN			BIT(1)
+#define STARFIVE_STA_OWN_MSK			0x3
+
+#define STARFIVE_NUM_LOCKS			16
+
+struct starfive_hwspinlock {
+	void __iomem *base;
+	struct reset_control *rst;
+	struct hwspinlock_device bank;
+};
+
+static int starfive_hwspinlock_trylock(struct hwspinlock *lock)
+{
+	struct starfive_hwspinlock *priv = dev_get_drvdata(lock->bank->dev);
+	int id = hwlock_to_id(lock);
+	u32 status;
+
+	writel(BIT(id), priv->base + STARFIVE_REG_APP_LOCK_REQ);
+	status = (readl(priv->base + STARFIVE_REG_LOCK_STA) >> (2 * id)) &
+		 STARFIVE_STA_OWN_MSK;
+
+	return (status == STARFIVE_STA_APP_OWN);
+}
+
+static void starfive_hwspinlock_unlock(struct hwspinlock *lock)
+{
+	struct starfive_hwspinlock *priv = dev_get_drvdata(lock->bank->dev);
+	int id = hwlock_to_id(lock);
+
+	writel(BIT(id), priv->base + STARFIVE_REG_APP_LOCK_RLS);
+}
+
+static void starfive_hwspinlock_relax(struct hwspinlock *lock)
+{
+	ndelay(50);
+}
+
+static const struct hwspinlock_ops starfive_hwspinlock_ops = {
+	.trylock	= starfive_hwspinlock_trylock,
+	.unlock		= starfive_hwspinlock_unlock,
+	.relax		= starfive_hwspinlock_relax,
+};
+
+static void starfive_hwspinlock_disable(void *data)
+{
+	struct starfive_hwspinlock *priv = data;
+
+	reset_control_assert(priv->rst);
+}
+
+static int starfive_hwspinlock_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct starfive_hwspinlock *priv;
+	int ret;
+
+	priv = devm_kzalloc(dev, struct_size(priv, bank.lock, STARFIVE_NUM_LOCKS),
+			    GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	priv->rst = devm_reset_control_array_get_exclusive(dev);
+	if (IS_ERR(priv->rst))
+		return dev_err_probe(dev, PTR_ERR(priv->rst),
+				     "failed to get reset\n");
+
+	ret = reset_control_deassert(priv->rst);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, priv);
+
+	ret = devm_add_action_or_reset(dev, starfive_hwspinlock_disable, priv);
+	if (ret)
+		goto fail_action;
+
+	return devm_hwspin_lock_register(dev, &priv->bank, &starfive_hwspinlock_ops,
+					 0, STARFIVE_NUM_LOCKS);
+
+fail_action:
+	reset_control_assert(priv->rst);
+	return ret;
+}
+
+static const struct of_device_id starfive_hwpinlock_ids[] = {
+	{ .compatible = "starfive,jhb100-hwspinlock", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, starfive_hwpinlock_ids);
+
+static struct platform_driver starfive_hwspinlock_driver = {
+	.probe		= starfive_hwspinlock_probe,
+	.driver		= {
+		.name	= "starfive_hwspinlock",
+		.of_match_table = starfive_hwpinlock_ids,
+	},
+};
+module_platform_driver(starfive_hwspinlock_driver);
+
+MODULE_AUTHOR("Xingyu Wu <xingyu.wu@starfivetech.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Hardware spinlock driver for StarFive JHB100 SoC");
-- 
2.34.1