[PATCH v7 2/3] reset: aspeed: register AST2700 reset auxiliary bus device

[Ryan Chen <ryan_chen@aspeedtech.com>]

The AST2700 reset driver is registered as an auxiliary device
due to reset and clock controller share the same register region.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
---
 drivers/reset/Kconfig             |   7 +
 drivers/reset/Makefile            |   1 +
 drivers/reset/reset-aspeed.c      | 302 ++++++++++++++++++++++++++++++
 include/soc/aspeed/reset-aspeed.h |  21 +++
 4 files changed, 331 insertions(+)
 create mode 100644 drivers/reset/reset-aspeed.c
 create mode 100644 include/soc/aspeed/reset-aspeed.h

diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 67bce340a87e..71a3accea7cb 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -22,6 +22,13 @@ config RESET_A10SR
 	  This option enables support for the external reset functions for
 	  peripheral PHYs on the Altera Arria10 System Resource Chip.
 
+config RESET_ASPEED
+	tristate "ASPEED Reset Driver"
+	depends on ARCH_ASPEED || COMPILE_TEST
+	select AUXILIARY_BUS
+	help
+	  This enables the reset controller driver for AST2700.
+
 config RESET_ATH79
 	bool "AR71xx Reset Driver" if COMPILE_TEST
 	default ATH79
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index 27b0bbdfcc04..97482bb56416 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -5,6 +5,7 @@ obj-y += starfive/
 obj-y += sti/
 obj-y += tegra/
 obj-$(CONFIG_RESET_A10SR) += reset-a10sr.o
+obj-$(CONFIG_RESET_ASPEED) += reset-aspeed.o
 obj-$(CONFIG_RESET_ATH79) += reset-ath79.o
 obj-$(CONFIG_RESET_AXS10X) += reset-axs10x.o
 obj-$(CONFIG_RESET_BCM6345) += reset-bcm6345.o
diff --git a/drivers/reset/reset-aspeed.c b/drivers/reset/reset-aspeed.c
new file mode 100644
index 000000000000..2dc8478af7b0
--- /dev/null
+++ b/drivers/reset/reset-aspeed.c
@@ -0,0 +1,302 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2024 ASPEED Technology Inc.
+ */
+
+#include <linux/auxiliary_bus.h>
+#include <linux/cleanup.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+
+#include <dt-bindings/reset/aspeed,ast2700-scu.h>
+#include <soc/aspeed/reset-aspeed.h>
+
+#define SCU0_RESET_CTRL1 0x200
+#define SCU0_RESET_CTRL2 0x220
+#define SCU1_RESET_CTRL1 0x200
+#define SCU1_RESET_CTRL2 0x220
+#define SCU1_PCIE3_CTRL 0x908
+
+struct ast2700_reset_signal {
+	bool dedicated_clr; /* dedicated reset clr offset */
+	u32 offset, bit;
+};
+
+struct aspeed_reset_info {
+	unsigned int nr_resets;
+	const struct ast2700_reset_signal *signal;
+};
+
+struct aspeed_reset {
+	struct reset_controller_dev rcdev;
+	struct aspeed_reset_info *info;
+	spinlock_t lock; /* Protect read-modify-write cycle */
+	void __iomem *base;
+};
+
+static const struct ast2700_reset_signal ast2700_reset0_signals[] = {
+	[SCU0_RESET_SDRAM] = { true, SCU0_RESET_CTRL1, BIT(0) },
+	[SCU0_RESET_DDRPHY] = { true, SCU0_RESET_CTRL1, BIT(1) },
+	[SCU0_RESET_RSA] = { true, SCU0_RESET_CTRL1, BIT(2) },
+	[SCU0_RESET_SHA3] = { true, SCU0_RESET_CTRL1, BIT(3) },
+	[SCU0_RESET_HACE] = { true, SCU0_RESET_CTRL1, BIT(4) },
+	[SCU0_RESET_SOC] = { true, SCU0_RESET_CTRL1, BIT(5) },
+	[SCU0_RESET_VIDEO] = { true, SCU0_RESET_CTRL1, BIT(6) },
+	[SCU0_RESET_2D] = { true, SCU0_RESET_CTRL1, BIT(7) },
+	[SCU0_RESET_PCIS] = { true, SCU0_RESET_CTRL1, BIT(8) },
+	[SCU0_RESET_RVAS0] = { true, SCU0_RESET_CTRL1, BIT(9) },
+	[SCU0_RESET_RVAS1] = { true, SCU0_RESET_CTRL1, BIT(10) },
+	[SCU0_RESET_SM3] = { true, SCU0_RESET_CTRL1, BIT(11) },
+	[SCU0_RESET_SM4] = { true, SCU0_RESET_CTRL1, BIT(12) },
+	[SCU0_RESET_CRT0] = { true, SCU0_RESET_CTRL1, BIT(13) },
+	[SCU0_RESET_ECC] = { true, SCU0_RESET_CTRL1, BIT(14) },
+	[SCU0_RESET_DP_PCI] = { true, SCU0_RESET_CTRL1, BIT(15) },
+	[SCU0_RESET_UFS] = { true, SCU0_RESET_CTRL1, BIT(16) },
+	[SCU0_RESET_EMMC] = { true, SCU0_RESET_CTRL1, BIT(17) },
+	[SCU0_RESET_PCIE1RST] = { true, SCU0_RESET_CTRL1, BIT(18) },
+	[SCU0_RESET_PCIE1RSTOE] = { true, SCU0_RESET_CTRL1, BIT(19) },
+	[SCU0_RESET_PCIE0RST] = { true, SCU0_RESET_CTRL1, BIT(20) },
+	[SCU0_RESET_PCIE0RSTOE] = { true, SCU0_RESET_CTRL1, BIT(21) },
+	[SCU0_RESET_JTAG] = { true, SCU0_RESET_CTRL1, BIT(22) },
+	[SCU0_RESET_MCTP0] = { true, SCU0_RESET_CTRL1, BIT(23) },
+	[SCU0_RESET_MCTP1] = { true, SCU0_RESET_CTRL1, BIT(24) },
+	[SCU0_RESET_XDMA0] = { true, SCU0_RESET_CTRL1, BIT(25) },
+	[SCU0_RESET_XDMA1] = { true, SCU0_RESET_CTRL1, BIT(26) },
+	[SCU0_RESET_H2X1] = { true, SCU0_RESET_CTRL1, BIT(27) },
+	[SCU0_RESET_DP] = { true, SCU0_RESET_CTRL1, BIT(28) },
+	[SCU0_RESET_DP_MCU] = { true, SCU0_RESET_CTRL1, BIT(29) },
+	[SCU0_RESET_SSP] = { true, SCU0_RESET_CTRL1, BIT(30) },
+	[SCU0_RESET_H2X0] = { true, SCU0_RESET_CTRL1, BIT(31) },
+	[SCU0_RESET_PORTA_VHUB] = { true, SCU0_RESET_CTRL2, BIT(0) },
+	[SCU0_RESET_PORTA_PHY3] = { true, SCU0_RESET_CTRL2, BIT(1) },
+	[SCU0_RESET_PORTA_XHCI] = { true, SCU0_RESET_CTRL2, BIT(2) },
+	[SCU0_RESET_PORTB_VHUB] = { true, SCU0_RESET_CTRL2, BIT(3) },
+	[SCU0_RESET_PORTB_PHY3] = { true, SCU0_RESET_CTRL2, BIT(4) },
+	[SCU0_RESET_PORTB_XHCI] = { true, SCU0_RESET_CTRL2, BIT(5) },
+	[SCU0_RESET_PORTA_VHUB_EHCI] = { true, SCU0_RESET_CTRL2, BIT(6) },
+	[SCU0_RESET_PORTB_VHUB_EHCI] = { true, SCU0_RESET_CTRL2, BIT(7) },
+	[SCU0_RESET_UHCI] = { true, SCU0_RESET_CTRL2, BIT(8) },
+	[SCU0_RESET_TSP] = { true, SCU0_RESET_CTRL2, BIT(9) },
+	[SCU0_RESET_E2M0] = { true, SCU0_RESET_CTRL2, BIT(10) },
+	[SCU0_RESET_E2M1] = { true, SCU0_RESET_CTRL2, BIT(11) },
+	[SCU0_RESET_VLINK] = { true, SCU0_RESET_CTRL2, BIT(12) },
+};
+
+static const struct ast2700_reset_signal ast2700_reset1_signals[] = {
+	[SCU1_RESET_LPC0] = { true, SCU1_RESET_CTRL1, BIT(0) },
+	[SCU1_RESET_LPC1] = { true, SCU1_RESET_CTRL1, BIT(1) },
+	[SCU1_RESET_MII] = { true, SCU1_RESET_CTRL1, BIT(2) },
+	[SCU1_RESET_PECI] = { true, SCU1_RESET_CTRL1, BIT(3) },
+	[SCU1_RESET_PWM] = { true, SCU1_RESET_CTRL1, BIT(4) },
+	[SCU1_RESET_MAC0] = { true, SCU1_RESET_CTRL1, BIT(5) },
+	[SCU1_RESET_MAC1] = { true, SCU1_RESET_CTRL1, BIT(6) },
+	[SCU1_RESET_MAC2] = { true, SCU1_RESET_CTRL1, BIT(7) },
+	[SCU1_RESET_ADC] = { true, SCU1_RESET_CTRL1, BIT(8) },
+	[SCU1_RESET_SD] = { true, SCU1_RESET_CTRL1, BIT(9) },
+	[SCU1_RESET_ESPI0] = { true, SCU1_RESET_CTRL1, BIT(10) },
+	[SCU1_RESET_ESPI1] = { true, SCU1_RESET_CTRL1, BIT(11) },
+	[SCU1_RESET_JTAG1] = { true, SCU1_RESET_CTRL1, BIT(12) },
+	[SCU1_RESET_SPI0] = { true, SCU1_RESET_CTRL1, BIT(13) },
+	[SCU1_RESET_SPI1] = { true, SCU1_RESET_CTRL1, BIT(14) },
+	[SCU1_RESET_SPI2] = { true, SCU1_RESET_CTRL1, BIT(15) },
+	[SCU1_RESET_I3C0] = { true, SCU1_RESET_CTRL1, BIT(16) },
+	[SCU1_RESET_I3C1] = { true, SCU1_RESET_CTRL1, BIT(17) },
+	[SCU1_RESET_I3C2] = { true, SCU1_RESET_CTRL1, BIT(18) },
+	[SCU1_RESET_I3C3] = { true, SCU1_RESET_CTRL1, BIT(19) },
+	[SCU1_RESET_I3C4] = { true, SCU1_RESET_CTRL1, BIT(20) },
+	[SCU1_RESET_I3C5] = { true, SCU1_RESET_CTRL1, BIT(21) },
+	[SCU1_RESET_I3C6] = { true, SCU1_RESET_CTRL1, BIT(22) },
+	[SCU1_RESET_I3C7] = { true, SCU1_RESET_CTRL1, BIT(23) },
+	[SCU1_RESET_I3C8] = { true, SCU1_RESET_CTRL1, BIT(24) },
+	[SCU1_RESET_I3C9] = { true, SCU1_RESET_CTRL1, BIT(25) },
+	[SCU1_RESET_I3C10] = { true, SCU1_RESET_CTRL1, BIT(26) },
+	[SCU1_RESET_I3C11] = { true, SCU1_RESET_CTRL1, BIT(27) },
+	[SCU1_RESET_I3C12] = { true, SCU1_RESET_CTRL1, BIT(28) },
+	[SCU1_RESET_I3C13] = { true, SCU1_RESET_CTRL1, BIT(29) },
+	[SCU1_RESET_I3C14] = { true, SCU1_RESET_CTRL1, BIT(30) },
+	[SCU1_RESET_I3C15] = { true, SCU1_RESET_CTRL1, BIT(31) },
+	[SCU1_RESET_MCU0] = { true, SCU1_RESET_CTRL2, BIT(0) },
+	[SCU1_RESET_MCU1] = { true, SCU1_RESET_CTRL2, BIT(1) },
+	[SCU1_RESET_H2A_SPI1] = { true, SCU1_RESET_CTRL2, BIT(2) },
+	[SCU1_RESET_H2A_SPI2] = { true, SCU1_RESET_CTRL2, BIT(3) },
+	[SCU1_RESET_UART0] = { true, SCU1_RESET_CTRL2, BIT(4) },
+	[SCU1_RESET_UART1] = { true, SCU1_RESET_CTRL2, BIT(5) },
+	[SCU1_RESET_UART2] = { true, SCU1_RESET_CTRL2, BIT(6) },
+	[SCU1_RESET_UART3] = { true, SCU1_RESET_CTRL2, BIT(7) },
+	[SCU1_RESET_I2C_FILTER] = { true, SCU1_RESET_CTRL2, BIT(8) },
+	[SCU1_RESET_CALIPTRA] = { true, SCU1_RESET_CTRL2, BIT(9) },
+	[SCU1_RESET_XDMA] = { true, SCU1_RESET_CTRL2, BIT(10) },
+	[SCU1_RESET_FSI] = { true, SCU1_RESET_CTRL2, BIT(12) },
+	[SCU1_RESET_CAN] = { true, SCU1_RESET_CTRL2, BIT(13) },
+	[SCU1_RESET_MCTP] = { true, SCU1_RESET_CTRL2, BIT(14) },
+	[SCU1_RESET_I2C] = { true, SCU1_RESET_CTRL2, BIT(15) },
+	[SCU1_RESET_UART6] = { true, SCU1_RESET_CTRL2, BIT(16) },
+	[SCU1_RESET_UART7] = { true, SCU1_RESET_CTRL2, BIT(17) },
+	[SCU1_RESET_UART8] = { true, SCU1_RESET_CTRL2, BIT(18) },
+	[SCU1_RESET_UART9] = { true, SCU1_RESET_CTRL2, BIT(19) },
+	[SCU1_RESET_LTPI0] = { true, SCU1_RESET_CTRL2, BIT(20) },
+	[SCU1_RESET_VGAL] = { true, SCU1_RESET_CTRL2, BIT(21) },
+	[SCU1_RESET_LTPI1] = { true, SCU1_RESET_CTRL2, BIT(22) },
+	[SCU1_RESET_ACE] = { true, SCU1_RESET_CTRL2, BIT(23) },
+	[SCU1_RESET_E2M] = { true, SCU1_RESET_CTRL2, BIT(24) },
+	[SCU1_RESET_UHCI] = { true, SCU1_RESET_CTRL2, BIT(25) },
+	[SCU1_RESET_PORTC_USB2UART] = { true, SCU1_RESET_CTRL2, BIT(26) },
+	[SCU1_RESET_PORTC_VHUB_EHCI] = { true, SCU1_RESET_CTRL2, BIT(27) },
+	[SCU1_RESET_PORTD_USB2UART] = { true, SCU1_RESET_CTRL2, BIT(28) },
+	[SCU1_RESET_PORTD_VHUB_EHCI] = { true, SCU1_RESET_CTRL2, BIT(29) },
+	[SCU1_RESET_H2X] = { true, SCU1_RESET_CTRL2, BIT(30) },
+	[SCU1_RESET_I3CDMA] = { true, SCU1_RESET_CTRL2, BIT(31) },
+	[SCU1_RESET_PCIE2RST] = { false, SCU1_PCIE3_CTRL, BIT(0) },
+};
+
+static inline struct aspeed_reset *to_aspeed_reset(struct reset_controller_dev *rcdev)
+{
+	return container_of(rcdev, struct aspeed_reset, rcdev);
+}
+
+static int aspeed_reset_assert(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	struct aspeed_reset *rc = to_aspeed_reset(rcdev);
+	void __iomem *reg_offset = rc->base + rc->info->signal[id].offset;
+
+	if (rc->info->signal[id].dedicated_clr) {
+		writel(rc->info->signal[id].bit, reg_offset);
+	} else {
+		guard(spinlock_irqsave)(&rc->lock);
+		writel(readl(reg_offset) & ~rc->info->signal[id].bit, reg_offset);
+	}
+
+	return 0;
+}
+
+static int aspeed_reset_deassert(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	struct aspeed_reset *rc = to_aspeed_reset(rcdev);
+	void __iomem *reg_offset = rc->base + rc->info->signal[id].offset;
+
+	if (rc->info->signal[id].dedicated_clr) {
+		writel(rc->info->signal[id].bit, reg_offset + 0x04);
+	} else {
+		guard(spinlock_irqsave)(&rc->lock);
+		writel(readl(reg_offset) | rc->info->signal[id].bit, reg_offset);
+	}
+
+	return 0;
+}
+
+static int aspeed_reset_status(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	struct aspeed_reset *rc = to_aspeed_reset(rcdev);
+	void __iomem *reg_offset = rc->base + rc->info->signal[id].offset;
+
+	return (readl(reg_offset) & rc->info->signal[id].bit) ? 1 : 0;
+}
+
+static const struct reset_control_ops aspeed_reset_ops = {
+	.assert = aspeed_reset_assert,
+	.deassert = aspeed_reset_deassert,
+	.status = aspeed_reset_status,
+};
+
+static int aspeed_reset_probe(struct auxiliary_device *adev,
+			      const struct auxiliary_device_id *id)
+{
+	struct aspeed_reset *reset;
+	struct device *dev = &adev->dev;
+
+	reset = devm_kzalloc(dev, sizeof(*reset), GFP_KERNEL);
+	if (!reset)
+		return -ENOMEM;
+
+	spin_lock_init(&reset->lock);
+
+	reset->info = (struct aspeed_reset_info *)id->driver_data;
+	reset->rcdev.owner = THIS_MODULE;
+	reset->rcdev.nr_resets = reset->info->nr_resets;
+	reset->rcdev.ops = &aspeed_reset_ops;
+	reset->rcdev.of_node = dev->parent->of_node;
+	reset->rcdev.dev = dev;
+	reset->rcdev.of_reset_n_cells = 1;
+	reset->base = (void __iomem *)adev->dev.platform_data;
+
+	return devm_reset_controller_register(dev, &reset->rcdev);
+}
+
+static void aspeed_reset_unregister_adev(void *_adev)
+{
+	struct auxiliary_device *adev = _adev;
+
+	auxiliary_device_delete(adev);
+	auxiliary_device_uninit(adev);
+}
+
+static void aspeed_reset_adev_release(struct device *dev)
+{
+	struct auxiliary_device *adev = to_auxiliary_dev(dev);
+
+	kfree(adev);
+}
+
+int aspeed_reset_controller_register(struct device *clk_dev, void __iomem *base,
+				     const char *adev_name)
+{
+	struct auxiliary_device *adev;
+	int ret;
+
+	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
+	if (!adev)
+		return -ENOMEM;
+
+	adev->name = adev_name;
+	adev->dev.parent = clk_dev;
+	adev->dev.release = aspeed_reset_adev_release;
+	adev->id = 666u;
+
+	ret = auxiliary_device_init(adev);
+	if (ret) {
+		kfree(adev);
+		return ret;
+	}
+
+	ret = auxiliary_device_add(adev);
+	if (ret) {
+		auxiliary_device_uninit(adev);
+		return ret;
+	}
+
+	adev->dev.platform_data = (__force void *)base;
+
+	return devm_add_action_or_reset(clk_dev, aspeed_reset_unregister_adev, adev);
+}
+EXPORT_SYMBOL_GPL(aspeed_reset_controller_register);
+
+static const struct aspeed_reset_info ast2700_reset0_info = {
+	.nr_resets = ARRAY_SIZE(ast2700_reset0_signals),
+	.signal = ast2700_reset0_signals,
+};
+
+static const struct aspeed_reset_info ast2700_reset1_info = {
+	.nr_resets = ARRAY_SIZE(ast2700_reset1_signals),
+	.signal = ast2700_reset1_signals,
+};
+
+static const struct auxiliary_device_id aspeed_reset_ids[] = {
+	{ .name = "reset_aspeed.reset0", .driver_data = (kernel_ulong_t)&ast2700_reset0_info },
+	{ .name = "reset_aspeed.reset1", .driver_data = (kernel_ulong_t)&ast2700_reset1_info },
+	{ }
+};
+MODULE_DEVICE_TABLE(auxiliary, aspeed_reset_ids);
+
+static struct auxiliary_driver aspeed_reset_driver = {
+	.probe		= aspeed_reset_probe,
+	.id_table	= aspeed_reset_ids,
+};
+
+module_auxiliary_driver(aspeed_reset_driver);
+
+MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>");
+MODULE_DESCRIPTION("ASPEED SoC Reset Controller Driver");
+MODULE_LICENSE("GPL");
diff --git a/include/soc/aspeed/reset-aspeed.h b/include/soc/aspeed/reset-aspeed.h
new file mode 100644
index 000000000000..51a4d13fbe3d
--- /dev/null
+++ b/include/soc/aspeed/reset-aspeed.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2024 ASPEED Technology Inc.
+ * Author: Ryan Chen <ryan_chen@aspeedtech.com>
+ */
+
+#ifndef __RESET_ASPEED_H__
+#define __RESET_ASPEED_H__
+
+#if IS_ENABLED(CONFIG_RESET_ASPEED)
+int aspeed_reset_controller_register(struct device *clk_dev, void __iomem *base,
+				     const char *adev_name);
+#else
+static inline int aspeed_reset_controller_register(struct device *clk_dev, void __iomem *base,
+				     const char *adev_name)
+{
+	return -ENODEV;
+}
+#endif /* if IS_ENABLED(CONFIG_RESET_ASPEED) */
+
+#endif /* __RESET_ASPEED_H__ */
-- 
2.34.1