microblaze: GPIO reset support (42a2478b) · Commits · github.com / kvm-riscv / linux

arch/microblaze/include/asm/setup.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -35,6 +35,8 @@ extern void mmu_reset(void);
		extern void early_console_reg_tlb_alloc(unsigned int addr);
		# endif /* CONFIG_MMU */

		extern void of_platform_reset_gpio_probe(void);

		void time_init(void);
		void init_IRQ(void);
		void machine_early_init(const char *cmdline, unsigned int ram,

arch/microblaze/kernel/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -7,7 +7,7 @@ extra-y := head.o vmlinux.lds
		obj-y += exceptions.o \
		hw_exception_handler.o init_task.o intc.o irq.o of_device.o \
		of_platform.o process.o prom.o prom_parse.o ptrace.o \
		setup.o signal.o sys_microblaze.o timer.o traps.o
		setup.o signal.o sys_microblaze.o timer.o traps.o reset.o

		obj-y += cpu/

arch/microblaze/kernel/reset.c

0 → 100644

+138 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
		* Copyright (C) 2009 PetaLogix
		*
		* This file is subject to the terms and conditions of the GNU General Public
		* License. See the file "COPYING" in the main directory of this archive
		* for more details.
		*/

		#include <linux/init.h>
		#include <linux/of_platform.h>
		#include <asm/prom.h>

		/* Trigger specific functions */
		#ifdef CONFIG_GPIOLIB

		#include <linux/of_gpio.h>

		static int handle; /* reset pin handle */

		static int of_reset_gpio_handle(void)
		{
		int ret; /* variable which stored handle reset gpio pin */
		struct device_node root; / root node */
		struct device_node gpio; / gpio node */
		struct of_gpio_chip *of_gc = NULL;
		enum of_gpio_flags flags ;
		const void *gpio_spec;

		/* find out root node */
		root = of_find_node_by_path("/");

		/* give me handle for gpio node to be possible allocate pin */
		ret = of_parse_phandles_with_args(root, "hard-reset-gpios",
		"#gpio-cells", 0, &gpio, &gpio_spec);
		if (ret) {
		pr_debug("%s: can't parse gpios property\n", __func__);
		goto err0;
		}

		of_gc = gpio->data;
		if (!of_gc) {
		pr_debug("%s: gpio controller %s isn't registered\n",
		root->full_name, gpio->full_name);
		ret = -ENODEV;
		goto err1;
		}

		ret = of_gc->xlate(of_gc, root, gpio_spec, &flags);
		if (ret < 0)
		goto err1;

		ret += of_gc->gc.base;
		err1:
		of_node_put(gpio);
		err0:
		pr_debug("%s exited with status %d\n", __func__, ret);
		return ret;
		}

		void of_platform_reset_gpio_probe(void)
		{
		int ret;
		handle = of_reset_gpio_handle();

		if (!gpio_is_valid(handle)) {
		printk(KERN_INFO "Skipping unavailable RESET gpio %d (%s)\n",
		handle, "reset");
		}

		ret = gpio_request(handle, "reset");
		if (ret < 0) {
		printk(KERN_INFO "GPIO pin is already allocated\n");
		return;
		}

		/* get current setup value */
		ret = gpio_get_value(handle);
		/* FIXME maybe worth to perform any action */
		pr_debug("Reset: Gpio output state: 0x%x\n", ret);

		/* Setup GPIO as output */
		ret = gpio_direction_output(handle, 0);
		if (ret < 0)
		goto err;

		/* Setup output direction */
		gpio_set_value(handle, 0);

		printk(KERN_INFO "Registered reset device: %d\n", handle);
		return;
		err:
		gpio_free(handle);
		return;
		}


		static void gpio_system_reset(void)
		{
		gpio_set_value(handle, 1);
		}
		#else
		#define gpio_system_reset() do {} while (0)
		void of_platform_reset_gpio_probe(void)
		{
		return;
		}
		#endif

		void machine_restart(char *cmd)
		{
		printk(KERN_NOTICE "Machine restart...\n");
		gpio_system_reset();
		dump_stack();
		while (1)
		;
		}

		void machine_shutdown(void)
		{
		printk(KERN_NOTICE "Machine shutdown...\n");
		while (1)
		;
		}

		void machine_halt(void)
		{
		printk(KERN_NOTICE "Machine halt...\n");
		while (1)
		;
		}

		void machine_power_off(void)
		{
		printk(KERN_NOTICE "Machine power off...\n");
		while (1)
		;
		}

arch/microblaze/kernel/setup.c

+0 −29

Original line number	Diff line number	Diff line
		@@ -186,32 +186,3 @@ static int microblaze_debugfs_init(void)
		}
		arch_initcall(microblaze_debugfs_init);
		#endif

		void machine_restart(char *cmd)
		{
		printk(KERN_NOTICE "Machine restart...\n");
		dump_stack();
		while (1)
		;
		}

		void machine_shutdown(void)
		{
		printk(KERN_NOTICE "Machine shutdown...\n");
		while (1)
		;
		}

		void machine_halt(void)
		{
		printk(KERN_NOTICE "Machine halt...\n");
		while (1)
		;
		}

		void machine_power_off(void)
		{
		printk(KERN_NOTICE "Machine power off...\n");
		while (1)
		;
		}

arch/microblaze/platform/generic/system.dts

+28 −0

Original line number	Diff line number	Diff line
		@@ -32,6 +32,7 @@ / {
		#address-cells = <1>;
		#size-cells = <1>;
		compatible = "xlnx,microblaze";
		hard-reset-gpios = <&LEDs_8Bit 2 1>;
		model = "testing";
		DDR2_SDRAM: memory@90000000 {
		device_type = "memory";
		@@ -261,6 +262,33 @@ LEDs_8Bit: gpio@81400000 {
		xlnx,is-dual = <0x0>;
		xlnx,tri-default = <0xffffffff>;
		xlnx,tri-default-2 = <0xffffffff>;
		#gpio-cells = <2>;
		gpio-controller;
		} ;

		gpio-leds {
		compatible = "gpio-leds";

		heartbeat {
		label = "Heartbeat";
		gpios = <&LEDs_8Bit 4 1>;
		linux,default-trigger = "heartbeat";
		};

		yellow {
		label = "Yellow";
		gpios = <&LEDs_8Bit 5 1>;
		};

		red {
		label = "Red";
		gpios = <&LEDs_8Bit 6 1>;
		};

		green {
		label = "Green";
		gpios = <&LEDs_8Bit 7 1>;
		};
		} ;
		RS232_Uart_1: serial@84000000 {
		clock-frequency = <125000000>;