Merge tag 'bcm2835-for-3.8-soc' of git://git.kernel.org/pub/scm/linux…

…/kernel/git/swarren/linux-rpi into next/soc

From Stephen Warren:
ARM: bcm2835: core SoC enhancements

A machine restart/reboot implementation is added. The GPIO/pinmux
controller is instantiated, and dummy gpio.h added.

* tag 'bcm2835-for-3.8-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-rpi:
  ARM: bcm2835: enable GPIO/pinctrl
  ARM: bcm2835: implement machine restart hook

Signed-off-by: Olof Johansson <olof@lixom.net>

Documentation/devicetree/bindings/watchdog/brcm,bcm2835-pm-wdog.txt

@@ -0,0 +1,13 @@
+BCM2835 Watchdog timer
+
+Required properties:
+
+- compatible : should be "brcm,bcm2835-pm-wdt"
+- reg : Specifies base physical address and size of the registers.
+
+Example:
+
+watchdog {
+	compatible = "brcm,bcm2835-pm-wdt";
+	reg = <0x7e100000 0x28>;
+};

arch/arm/Kconfig

@@ -336,15 +336,18 @@ config ARCH_AT91
 
 config ARCH_BCM2835
 	bool "Broadcom BCM2835 family"
-	select ARCH_WANT_OPTIONAL_GPIOLIB
+	select ARCH_REQUIRE_GPIOLIB
 	select ARM_AMBA
 	select ARM_ERRATA_411920
 	select ARM_TIMER_SP804
 	select CLKDEV_LOOKUP
 	select COMMON_CLK
 	select CPU_V6
 	select GENERIC_CLOCKEVENTS
+	select GENERIC_GPIO
 	select MULTI_IRQ_HANDLER
+	select PINCTRL
+	select PINCTRL_BCM2835
 	select SPARSE_IRQ
 	select USE_OF
 	help

arch/arm/boot/dts/bcm2835-rpi-b.dts

@@ -10,3 +10,18 @@
 		reg = <0 0x10000000>;
 	};
 };
+
+&gpio {
+	pinctrl-names = "default";
+	pinctrl-0 = <&alt0 &alt3>;
+
+	alt0: alt0 {
+		brcm,pins = <0 1 2 3 4 5 6 7 8 9 10 11 14 15 40 45>;
+		brcm,function = <4>; /* alt0 */
+	};
+
+	alt3: alt3 {
+		brcm,pins = <48 49 50 51 52 53>;
+		brcm,function = <7>; /* alt3 */
+	};
+};

arch/arm/boot/dts/bcm2835.dtsi

@@ -29,11 +29,39 @@
 			#interrupt-cells = <2>;
 		};
 
+		watchdog {
+			compatible = "brcm,bcm2835-pm-wdt";
+			reg = <0x7e100000 0x28>;
+		};
+
 		uart@20201000 {
 			compatible = "brcm,bcm2835-pl011", "arm,pl011", "arm,primecell";
 			reg = <0x7e201000 0x1000>;
 			interrupts = <2 25>;
 			clock-frequency = <3000000>;
 		};
+
+		gpio: gpio {
+			compatible = "brcm,bcm2835-gpio";
+			reg = <0x7e200000 0xb4>;
+			/*
+			 * The GPIO IP block is designed for 3 banks of GPIOs.
+			 * Each bank has a GPIO interrupt for itself.
+			 * There is an overall "any bank" interrupt.
+			 * In order, these are GIC interrupts 17, 18, 19, 20.
+			 * Since the BCM2835 only has 2 banks, the 2nd bank
+			 * interrupt output appears to be mirrored onto the
+			 * 3rd bank's interrupt signal.
+			 * So, a bank0 interrupt shows up on 17, 20, and
+			 * a bank1 interrupt shows up on 18, 19, 20!
+			 */
+			interrupts = <2 17>, <2 18>, <2 19>, <2 20>;
+
+			gpio-controller;
+			#gpio-cells = <2>;
+
+			interrupt-controller;
+			#interrupt-cells = <2>;
+		};
 	};
 };

arch/arm/mach-bcm2835/bcm2835.c

@@ -12,8 +12,10 @@
  * GNU General Public License for more details.
  */
 
+#include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/irqchip/bcm2835.h>
+#include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/bcm2835_timer.h>
 #include <linux/clk/bcm2835.h>
@@ -23,6 +25,48 @@
 
 #include <mach/bcm2835_soc.h>
 
+#define PM_RSTC				0x1c
+#define PM_WDOG				0x24
+
+#define PM_PASSWORD			0x5a000000
+#define PM_RSTC_WRCFG_MASK		0x00000030
+#define PM_RSTC_WRCFG_FULL_RESET	0x00000020
+
+static void __iomem *wdt_regs;
+
+/*
+ * The machine restart method can be called from an atomic context so we won't
+ * be able to ioremap the regs then.
+ */
+static void bcm2835_setup_restart(void)
+{
+	struct device_node *np = of_find_compatible_node(NULL, NULL,
+						"brcm,bcm2835-pm-wdt");
+	if (WARN(!np, "unable to setup watchdog restart"))
+		return;
+
+	wdt_regs = of_iomap(np, 0);
+	WARN(!wdt_regs, "failed to remap watchdog regs");
+}
+
+static void bcm2835_restart(char mode, const char *cmd)
+{
+	u32 val;
+
+	if (!wdt_regs)
+		return;
+
+	/* use a timeout of 10 ticks (~150us) */
+	writel_relaxed(10 | PM_PASSWORD, wdt_regs + PM_WDOG);
+	val = readl_relaxed(wdt_regs + PM_RSTC);
+	val &= ~PM_RSTC_WRCFG_MASK;
+	val |= PM_PASSWORD | PM_RSTC_WRCFG_FULL_RESET;
+	writel_relaxed(val, wdt_regs + PM_RSTC);
+
+	/* No sleeping, possibly atomic. */
+	mdelay(1);
+}
+
 static struct map_desc io_map __initdata = {
 	.virtual = BCM2835_PERIPH_VIRT,
 	.pfn = __phys_to_pfn(BCM2835_PERIPH_PHYS),
@@ -39,6 +83,7 @@ void __init bcm2835_init(void)
 {
 	int ret;
 
+	bcm2835_setup_restart();
 	bcm2835_init_clocks();
 
 	ret = of_platform_populate(NULL, of_default_bus_match_table, NULL,
@@ -60,5 +105,6 @@ DT_MACHINE_START(BCM2835, "BCM2835")
 	.handle_irq = bcm2835_handle_irq,
 	.init_machine = bcm2835_init,
 	.timer = &bcm2835_timer,
+	.restart = bcm2835_restart,
 	.dt_compat = bcm2835_compat
 MACHINE_END

arch/arm/mach-bcm2835/include/mach/gpio.h

@@ -0,0 +1 @@
+/* empty */