[PATCH v14 2/3] reset: aspeed: register AST2700 reset auxiliary bus device

Ryan Chen
2025-09-17T02:05:53Z

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 | 253 +++++++++++++++++++++++++++++++++++
3 files changed, 261 insertions(+)
create mode 100644 drivers/reset/reset-aspeed.c

diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 635eef469ab7..78b7078478d4 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 a917d2522e8d..f7934f9fb90b 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -6,6 +6,7 @@ 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..dd2f860a69d7
--- /dev/null
+++ b/drivers/reset/reset-aspeed.c
@@ -0,0 +1,253 @@
+// 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>
+
+#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 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 = "clk_ast2700.reset0", .driver_data = (kernel_ulong_t)&ast2700_reset0_info },
+ { .name = "clk_ast2700.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");
--
2.34.1