microblaze: GPIO reset support

Signed-off-by: Michal Simek <monstr@monstr.eu>

diff --git a/arch/microblaze/include/asm/setup.h b/arch/microblaze/include/asm/setup.h
index ed67c9e..7f31394 100644 (file)
--- a/arch/microblaze/include/asm/setup.h
+++ b/arch/microblaze/include/asm/setup.h
@@ -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,

diff --git a/arch/microblaze/kernel/Makefile b/arch/microblaze/kernel/Makefile
index d487729..fddd0c4 100644 (file)
--- a/arch/microblaze/kernel/Makefile
+++ b/arch/microblaze/kernel/Makefile
@@ -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/
 

diff --git a/arch/microblaze/kernel/reset.c b/arch/microblaze/kernel/reset.c
new file mode 100644 (file)
index 0000000..ce74a6f
--- /dev/null
+++ b/arch/microblaze/kernel/reset.c
@@ -0,0 +1,138 @@
+/*
+ * 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)
+               ;
+}

diff --git a/arch/microblaze/kernel/setup.c b/arch/microblaze/kernel/setup.c
index 8c1e0f4..367ad33 100644 (file)
--- a/arch/microblaze/kernel/setup.c
+++ b/arch/microblaze/kernel/setup.c
@@ -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)
-               ;
-}

diff --git a/arch/microblaze/platform/generic/system.dts b/arch/microblaze/platform/generic/system.dts
index 29993f6..e00da89 100644 (file)
--- a/arch/microblaze/platform/generic/system.dts
+++ b/arch/microblaze/platform/generic/system.dts
@@ -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 @@
                        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>;

diff --git a/arch/microblaze/platform/platform.c b/arch/microblaze/platform/platform.c
index 56e0234..5b89b58 100644 (file)
--- a/arch/microblaze/platform/platform.c
+++ b/arch/microblaze/platform/platform.c
@@ -13,6 +13,7 @@
 #include <linux/init.h>
 #include <linux/of_platform.h>
 #include <asm/prom.h>
+#include <asm/setup.h>
 
 static struct of_device_id xilinx_of_bus_ids[] __initdata = {
        { .compatible = "simple-bus", },
@@ -26,6 +27,7 @@ static struct of_device_id xilinx_of_bus_ids[] __initdata = {
 static int __init microblaze_device_probe(void)
 {
        of_platform_bus_probe(NULL, xilinx_of_bus_ids, NULL);
+       of_platform_reset_gpio_probe();
        return 0;
 }
 device_initcall(microblaze_device_probe);