[PATCH 4/5] reset: anlogic: add support for Anlogic DR1V90 resets

[Junhui Liu <junhui.liu@pigmoral.tech>]

Add reset controller support for the Anlogic DR1V90 SoC, which is an
auxiliary device associated with the Clock and Reset Unit (CRU). All
resets are active-low.

Signed-off-by: Junhui Liu <junhui.liu@pigmoral.tech>
---
 drivers/reset/Kconfig        |   9 +++
 drivers/reset/Makefile       |   1 +
 drivers/reset/reset-dr1v90.c | 136 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 146 insertions(+)

diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 635eef469ab797ac8ef39d95a82d47071aeec630..bc7a1abb907806a1efaf568ee3dc3ca6081f667b 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -66,6 +66,15 @@ config RESET_BRCMSTB_RESCAL
 	  This enables the RESCAL reset controller for SATA, PCIe0, or PCIe1 on
 	  BCM7216 or the BCM2712.
 
+config RESET_DR1V90
+	tristate "Anlogic DR1V90 reset controller"
+	depends on ARCH_ANLOGIC || COMPILE_TEST
+	select AUXILIARY_BUS
+	default ARCH_ANLOGIC
+	help
+	  This enables the reset controller driver for Anlogic DR1V90 SoCs
+	  provided by the CRU unit.
+
 config RESET_EYEQ
 	bool "Mobileye EyeQ reset controller"
 	depends on MACH_EYEQ5 || MACH_EYEQ6H || COMPILE_TEST
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index a917d2522e8d12af0dd2b252e493fa4fc9eabecf..441307fd6ccd6fe0793fe819a60e66888efcb92c 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_RESET_BCM6345) += reset-bcm6345.o
 obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o
 obj-$(CONFIG_RESET_BRCMSTB) += reset-brcmstb.o
 obj-$(CONFIG_RESET_BRCMSTB_RESCAL) += reset-brcmstb-rescal.o
+obj-$(CONFIG_RESET_DR1V90) += reset-dr1v90.o
 obj-$(CONFIG_RESET_EYEQ) += reset-eyeq.o
 obj-$(CONFIG_RESET_GPIO) += reset-gpio.o
 obj-$(CONFIG_RESET_HSDK) += reset-hsdk.o
diff --git a/drivers/reset/reset-dr1v90.c b/drivers/reset/reset-dr1v90.c
new file mode 100644
index 0000000000000000000000000000000000000000..914bbb9331969939f039bfb3caa6ef9d88a48b96
--- /dev/null
+++ b/drivers/reset/reset-dr1v90.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2025 Shanghai Anlogic Infotech Co., Ltd.
+ * Copyright (c) 2025 Junhui Liu <junhui.liu@pigmoral.tech>
+ */
+
+#include <linux/auxiliary_bus.h>
+#include "linux/device.h"
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/reset-controller.h>
+
+#include <dt-bindings/reset/anlogic,dr1v90-cru.h>
+
+struct dr1v90_reset_map {
+	u32 offset;
+	u32 bit;
+};
+
+struct dr1v90_reset_controller {
+	struct reset_controller_dev rcdev;
+	void __iomem *base;
+};
+
+static inline struct dr1v90_reset_controller *
+to_dr1v90_reset_controller(struct reset_controller_dev *rcdev)
+{
+	return container_of(rcdev, struct dr1v90_reset_controller, rcdev);
+}
+
+static const struct dr1v90_reset_map dr1v90_resets[] = {
+	[RESET_OCM]		= { 0x74, BIT(4)},
+	[RESET_QSPI]		= { 0x74, BIT(5)},
+	[RESET_SMC]		= { 0x74, BIT(6)},
+	[RESET_WDT]		= { 0x74, BIT(7)},
+	[RESET_DMAC_AXI]	= { 0x74, BIT(8)},
+	[RESET_DMAC_AHB]	= { 0x74, BIT(9)},
+	[RESET_NPU]		= { 0x74, BIT(12)},
+	[RESET_JPU]		= { 0x74, BIT(13)},
+	[RESET_DDRBUS]		= { 0x74, BIT(14)},
+	[RESET_NIC_HP0]		= { 0x78, BIT(0)},
+	[RESET_NIC_HP1]		= { 0x78, BIT(1)},
+	[RESET_NIC_GP0M]	= { 0x78, BIT(4)},
+	[RESET_NIC_GP1M]	= { 0x78, BIT(5)},
+	[RESET_GPIO]		= { 0x78, BIT(8)},
+	[RESET_IPC]		= { 0x78, BIT(12)},
+	[RESET_USB0]		= { 0x7C, BIT(0)},
+	[RESET_USB1]		= { 0x7C, BIT(1)},
+	[RESET_GBE0]		= { 0x7C, BIT(4)},
+	[RESET_GBE1]		= { 0x7C, BIT(5)},
+	[RESET_SDIO0]		= { 0x7C, BIT(8)},
+	[RESET_SDIO1]		= { 0x7C, BIT(9)},
+	[RESET_UART0]		= { 0x7C, BIT(12)},
+	[RESET_UART1]		= { 0x7C, BIT(13)},
+	[RESET_SPI0]		= { 0x7C, BIT(16)},
+	[RESET_SPI1]		= { 0x7C, BIT(17)},
+	[RESET_CAN0]		= { 0x7C, BIT(20)},
+	[RESET_CAN1]		= { 0x7C, BIT(21)},
+	[RESET_TTC0]		= { 0x7C, BIT(24)},
+	[RESET_TTC1]		= { 0x7C, BIT(25)},
+	[RESET_I2C0]		= { 0x7C, BIT(28)},
+	[RESET_I2C1]		= { 0x7C, BIT(29)}
+};
+
+static int dr1v90_reset_control_update(struct reset_controller_dev *rcdev,
+				       unsigned long id, bool assert)
+{
+	struct dr1v90_reset_controller *rstc = to_dr1v90_reset_controller(rcdev);
+	u32 offset = dr1v90_resets[id].offset;
+	u32 bit = dr1v90_resets[id].bit;
+	u32 reg;
+
+	reg = readl(rstc->base + offset);
+	if (assert)
+		reg &= ~bit;
+	else
+		reg |= bit;
+	writel(reg, rstc->base + offset);
+
+	return 0;
+}
+
+static int dr1v90_reset_control_assert(struct reset_controller_dev *rcdev,
+				       unsigned long id)
+{
+	return dr1v90_reset_control_update(rcdev, id, true);
+}
+
+static int dr1v90_reset_control_deassert(struct reset_controller_dev *rcdev,
+					 unsigned long id)
+{
+	return dr1v90_reset_control_update(rcdev, id, false);
+}
+
+static const struct reset_control_ops dr1v90_reset_control_ops = {
+	.assert = dr1v90_reset_control_assert,
+	.deassert = dr1v90_reset_control_deassert,
+};
+
+static int dr1v90_reset_probe(struct auxiliary_device *adev,
+			      const struct auxiliary_device_id *id)
+{
+	struct dr1v90_reset_controller *rstc;
+	struct device *dev = &adev->dev;
+
+	rstc = devm_kzalloc(dev, sizeof(*rstc), GFP_KERNEL);
+	if (!rstc)
+		return -ENOMEM;
+
+	rstc->base = of_iomap(dev->parent->of_node, 0);
+	rstc->rcdev.dev = dev;
+	rstc->rcdev.nr_resets = ARRAY_SIZE(dr1v90_resets);
+	rstc->rcdev.of_node = dev->parent->of_node;
+	rstc->rcdev.ops = &dr1v90_reset_control_ops;
+	rstc->rcdev.owner = THIS_MODULE;
+
+	return devm_reset_controller_register(dev, &rstc->rcdev);
+}
+
+static const struct auxiliary_device_id dr1v90_reset_ids[] = {
+	{
+		.name = "anlogic_dr1v90_cru.reset"
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(auxiliary, dr1v90_reset_ids);
+
+static struct auxiliary_driver dr1v90_reset_driver = {
+	.probe = dr1v90_reset_probe,
+	.id_table = dr1v90_reset_ids,
+};
+module_auxiliary_driver(dr1v90_reset_driver);
+
+MODULE_AUTHOR("Junhui Liu <junhui.liu@pigmoral.tech>");
+MODULE_DESCRIPTION("Anlogic DR1V90 reset controller driver");
+MODULE_LICENSE("GPL");

-- 
2.51.0