Merge branch 'nuvoton/ma35d1' into soc/newsoc

This patchset adds initial support for the Nuvoton ma35d1 SoC, including
initial device tree, clock driver, reset driver, and serial driver.

This patchset cover letter is based from the initial support for Nuvoton
ma35d1 to keep tracking the version history.

This patchset had been applied to Linux kernel 6.4.0-rc5
and tested on the Nuvoton ma35d1 SOM evaluation board.

(ma35d1 information: https://www.nuvoton.com/products/microprocessors/arm-cortex-a35-mpus/)
MA35D1 porting on linux-5.10.y can be found at: https://github.com/OpenNuvoton/MPU-Family

Link: https://lore.kernel.org/linux-arm-kernel/20230605040749.67964-1-ychuang570808@gmail.com/

[arnd: merging everything aside from the serial port driver for now, as
 that is still waiting for an Ack]

* nuvoton/ma35d1:
  reset: Add Nuvoton ma35d1 reset driver support
  clk: nuvoton: Add clock driver for ma35d1 clock controller
  arm64: dts: nuvoton: Add initial ma35d1 device tree
  dt-bindings: serial: Document ma35d1 uart controller
  dt-bindings: arm: Add initial bindings for Nuvoton platform
  dt-bindings: reset: nuvoton: Document ma35d1 reset control
  dt-bindings: clock: nuvoton: add binding for ma35d1 clock controller
  arm64: defconfig: Add support for Nuvoton MA35 family SoCs
  arm64: Kconfig.platforms: Add config for Nuvoton MA35 platform

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

3 files changed, 242 insertions, 0 deletions

diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 6aa8f243b30c..07499177a266 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -143,6 +143,12 @@ config RESET_NPCM
 	  This enables the reset controller driver for Nuvoton NPCM
 	  BMC SoCs.
 
+config RESET_NUVOTON_MA35D1
+	bool "Nuvton MA35D1 Reset Driver"
+	default ARCH_MA35 || COMPILE_TEST
+	help
+	  This enables the reset controller driver for Nuvoton MA35D1 SoC.
+
 config RESET_OXNAS
 	bool
 
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index 7fec5af6c964..411b45ba0da7 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_RESET_MCHP_SPARX5) += reset-microchip-sparx5.o
 obj-$(CONFIG_RESET_MESON) += reset-meson.o
 obj-$(CONFIG_RESET_MESON_AUDIO_ARB) += reset-meson-audio-arb.o
 obj-$(CONFIG_RESET_NPCM) += reset-npcm.o
+obj-$(CONFIG_RESET_NUVOTON_MA35D1) += reset-ma35d1.o
 obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o
 obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o
 obj-$(CONFIG_RESET_POLARFIRE_SOC) += reset-mpfs.o
diff --git a/drivers/reset/reset-ma35d1.c b/drivers/reset/reset-ma35d1.c
new file mode 100644
index 000000000000..54e53863c98a
--- /dev/null
+++ b/drivers/reset/reset-ma35d1.c
@@ -0,0 +1,235 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2023 Nuvoton Technology Corp.
+ * Author: Chi-Fang Li <cfli0@nuvoton.com>
+ */
+
+#include <linux/bits.h>
+#include <linux/container_of.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/reset-controller.h>
+#include <linux/spinlock.h>
+#include <dt-bindings/reset/nuvoton,ma35d1-reset.h>
+
+struct ma35d1_reset_data {
+	struct reset_controller_dev rcdev;
+	struct notifier_block restart_handler;
+	void __iomem *base;
+	/* protect registers against concurrent read-modify-write */
+	spinlock_t lock;
+};
+
+static const struct {
+	u32 reg_ofs;
+	u32 bit;
+} ma35d1_reset_map[] = {
+	[MA35D1_RESET_CHIP] =    {0x20, 0},
+	[MA35D1_RESET_CA35CR0] = {0x20, 1},
+	[MA35D1_RESET_CA35CR1] = {0x20, 2},
+	[MA35D1_RESET_CM4] =     {0x20, 3},
+	[MA35D1_RESET_PDMA0] =   {0x20, 4},
+	[MA35D1_RESET_PDMA1] =   {0x20, 5},
+	[MA35D1_RESET_PDMA2] =   {0x20, 6},
+	[MA35D1_RESET_PDMA3] =   {0x20, 7},
+	[MA35D1_RESET_DISP] =    {0x20, 9},
+	[MA35D1_RESET_VCAP0] =   {0x20, 10},
+	[MA35D1_RESET_VCAP1] =   {0x20, 11},
+	[MA35D1_RESET_GFX] =     {0x20, 12},
+	[MA35D1_RESET_VDEC] =    {0x20, 13},
+	[MA35D1_RESET_WHC0] =    {0x20, 14},
+	[MA35D1_RESET_WHC1] =    {0x20, 15},
+	[MA35D1_RESET_GMAC0] =   {0x20, 16},
+	[MA35D1_RESET_GMAC1] =   {0x20, 17},
+	[MA35D1_RESET_HWSEM] =   {0x20, 18},
+	[MA35D1_RESET_EBI] =     {0x20, 19},
+	[MA35D1_RESET_HSUSBH0] = {0x20, 20},
+	[MA35D1_RESET_HSUSBH1] = {0x20, 21},
+	[MA35D1_RESET_HSUSBD] =  {0x20, 22},
+	[MA35D1_RESET_USBHL] =   {0x20, 23},
+	[MA35D1_RESET_SDH0] =    {0x20, 24},
+	[MA35D1_RESET_SDH1] =    {0x20, 25},
+	[MA35D1_RESET_NAND] =    {0x20, 26},
+	[MA35D1_RESET_GPIO] =    {0x20, 27},
+	[MA35D1_RESET_MCTLP] =   {0x20, 28},
+	[MA35D1_RESET_MCTLC] =   {0x20, 29},
+	[MA35D1_RESET_DDRPUB] =  {0x20, 30},
+	[MA35D1_RESET_TMR0] =    {0x24, 2},
+	[MA35D1_RESET_TMR1] =    {0x24, 3},
+	[MA35D1_RESET_TMR2] =    {0x24, 4},
+	[MA35D1_RESET_TMR3] =    {0x24, 5},
+	[MA35D1_RESET_I2C0] =    {0x24, 8},
+	[MA35D1_RESET_I2C1] =    {0x24, 9},
+	[MA35D1_RESET_I2C2] =    {0x24, 10},
+	[MA35D1_RESET_I2C3] =    {0x24, 11},
+	[MA35D1_RESET_QSPI0] =   {0x24, 12},
+	[MA35D1_RESET_SPI0] =    {0x24, 13},
+	[MA35D1_RESET_SPI1] =    {0x24, 14},
+	[MA35D1_RESET_SPI2] =    {0x24, 15},
+	[MA35D1_RESET_UART0] =   {0x24, 16},
+	[MA35D1_RESET_UART1] =   {0x24, 17},
+	[MA35D1_RESET_UART2] =   {0x24, 18},
+	[MA35D1_RESET_UART3] =   {0x24, 19},
+	[MA35D1_RESET_UART4] =   {0x24, 20},
+	[MA35D1_RESET_UART5] =   {0x24, 21},
+	[MA35D1_RESET_UART6] =   {0x24, 22},
+	[MA35D1_RESET_UART7] =   {0x24, 23},
+	[MA35D1_RESET_CANFD0] =  {0x24, 24},
+	[MA35D1_RESET_CANFD1] =  {0x24, 25},
+	[MA35D1_RESET_EADC0] =   {0x24, 28},
+	[MA35D1_RESET_I2S0] =    {0x24, 29},
+	[MA35D1_RESET_SC0] =     {0x28, 0},
+	[MA35D1_RESET_SC1] =     {0x28, 1},
+	[MA35D1_RESET_QSPI1] =   {0x28, 4},
+	[MA35D1_RESET_SPI3] =    {0x28, 6},
+	[MA35D1_RESET_EPWM0] =   {0x28, 16},
+	[MA35D1_RESET_EPWM1] =   {0x28, 17},
+	[MA35D1_RESET_QEI0] =    {0x28, 22},
+	[MA35D1_RESET_QEI1] =    {0x28, 23},
+	[MA35D1_RESET_ECAP0] =   {0x28, 26},
+	[MA35D1_RESET_ECAP1] =   {0x28, 27},
+	[MA35D1_RESET_CANFD2] =  {0x28, 28},
+	[MA35D1_RESET_ADC0] =    {0x28, 31},
+	[MA35D1_RESET_TMR4] =    {0x2C, 0},
+	[MA35D1_RESET_TMR5] =    {0x2C, 1},
+	[MA35D1_RESET_TMR6] =    {0x2C, 2},
+	[MA35D1_RESET_TMR7] =    {0x2C, 3},
+	[MA35D1_RESET_TMR8] =    {0x2C, 4},
+	[MA35D1_RESET_TMR9] =    {0x2C, 5},
+	[MA35D1_RESET_TMR10] =   {0x2C, 6},
+	[MA35D1_RESET_TMR11] =   {0x2C, 7},
+	[MA35D1_RESET_UART8] =   {0x2C, 8},
+	[MA35D1_RESET_UART9] =   {0x2C, 9},
+	[MA35D1_RESET_UART10] =  {0x2C, 10},
+	[MA35D1_RESET_UART11] =  {0x2C, 11},
+	[MA35D1_RESET_UART12] =  {0x2C, 12},
+	[MA35D1_RESET_UART13] =  {0x2C, 13},
+	[MA35D1_RESET_UART14] =  {0x2C, 14},
+	[MA35D1_RESET_UART15] =  {0x2C, 15},
+	[MA35D1_RESET_UART16] =  {0x2C, 16},
+	[MA35D1_RESET_I2S1] =    {0x2C, 17},
+	[MA35D1_RESET_I2C4] =    {0x2C, 18},
+	[MA35D1_RESET_I2C5] =    {0x2C, 19},
+	[MA35D1_RESET_EPWM2] =   {0x2C, 20},
+	[MA35D1_RESET_ECAP2] =   {0x2C, 21},
+	[MA35D1_RESET_QEI2] =    {0x2C, 22},
+	[MA35D1_RESET_CANFD3] =  {0x2C, 23},
+	[MA35D1_RESET_KPI] =     {0x2C, 24},
+	[MA35D1_RESET_GIC] =     {0x2C, 28},
+	[MA35D1_RESET_SSMCC] =   {0x2C, 30},
+	[MA35D1_RESET_SSPCC] =   {0x2C, 31}
+};
+
+static int ma35d1_restart_handler(struct notifier_block *this, unsigned long mode, void *cmd)
+{
+	struct ma35d1_reset_data *data =
+				 container_of(this, struct ma35d1_reset_data, restart_handler);
+	u32 id = MA35D1_RESET_CHIP;
+
+	writel_relaxed(BIT(ma35d1_reset_map[id].bit),
+		       data->base + ma35d1_reset_map[id].reg_ofs);
+	return 0;
+}
+
+static int ma35d1_reset_update(struct reset_controller_dev *rcdev, unsigned long id, bool assert)
+{
+	struct ma35d1_reset_data *data = container_of(rcdev, struct ma35d1_reset_data, rcdev);
+	unsigned long flags;
+	u32 reg;
+
+	if (WARN_ON_ONCE(id >= ARRAY_SIZE(ma35d1_reset_map)))
+		return -EINVAL;
+
+	spin_lock_irqsave(&data->lock, flags);
+	reg = readl_relaxed(data->base + ma35d1_reset_map[id].reg_ofs);
+	if (assert)
+		reg |= BIT(ma35d1_reset_map[id].bit);
+	else
+		reg &= ~(BIT(ma35d1_reset_map[id].bit));
+	writel_relaxed(reg, data->base + ma35d1_reset_map[id].reg_ofs);
+	spin_unlock_irqrestore(&data->lock, flags);
+
+	return 0;
+}
+
+static int ma35d1_reset_assert(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	return ma35d1_reset_update(rcdev, id, true);
+}
+
+static int ma35d1_reset_deassert(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	return ma35d1_reset_update(rcdev, id, false);
+}
+
+static int ma35d1_reset_status(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	struct ma35d1_reset_data *data = container_of(rcdev, struct ma35d1_reset_data, rcdev);
+	u32 reg;
+
+	if (WARN_ON_ONCE(id >= ARRAY_SIZE(ma35d1_reset_map)))
+		return -EINVAL;
+
+	reg = readl_relaxed(data->base + ma35d1_reset_map[id].reg_ofs);
+	return !!(reg & BIT(ma35d1_reset_map[id].bit));
+}
+
+static const struct reset_control_ops ma35d1_reset_ops = {
+	.assert = ma35d1_reset_assert,
+	.deassert = ma35d1_reset_deassert,
+	.status = ma35d1_reset_status,
+};
+
+static const struct of_device_id ma35d1_reset_dt_ids[] = {
+	{ .compatible = "nuvoton,ma35d1-reset" },
+	{ },
+};
+
+static int ma35d1_reset_probe(struct platform_device *pdev)
+{
+	struct ma35d1_reset_data *reset_data;
+	struct device *dev = &pdev->dev;
+	int err;
+
+	if (!pdev->dev.of_node) {
+		dev_err(&pdev->dev, "Device tree node not found\n");
+		return -EINVAL;
+	}
+
+	reset_data = devm_kzalloc(dev, sizeof(*reset_data), GFP_KERNEL);
+	if (!reset_data)
+		return -ENOMEM;
+
+	reset_data->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(reset_data->base))
+		return PTR_ERR(reset_data->base);
+
+	reset_data->rcdev.owner = THIS_MODULE;
+	reset_data->rcdev.nr_resets = MA35D1_RESET_COUNT;
+	reset_data->rcdev.ops = &ma35d1_reset_ops;
+	reset_data->rcdev.of_node = dev->of_node;
+	reset_data->restart_handler.notifier_call = ma35d1_restart_handler;
+	reset_data->restart_handler.priority = 192;
+	spin_lock_init(&reset_data->lock);
+
+	err = register_restart_handler(&reset_data->restart_handler);
+	if (err)
+		dev_warn(&pdev->dev, "failed to register restart handler\n");
+
+	return devm_reset_controller_register(dev, &reset_data->rcdev);
+}
+
+static struct platform_driver ma35d1_reset_driver = {
+	.probe = ma35d1_reset_probe,
+	.driver = {
+		.name = "ma35d1-reset",
+		.of_match_table	= ma35d1_reset_dt_ids,
+	},
+};
+
+builtin_platform_driver(ma35d1_reset_driver);