[ARM] 3140/1: NSLU2 machine support

Patch from Alessandro Zummo

This patch adds support for the LinkSys NSLU2 running with
both big and little-endian kernels. The LinkSys NSLU2 is
a cost engineered ARM, XScale 420 based system similar to
the the Intel IXDP425 evaluation board. It uses the
IXP4XX ARCH.

While this patch applies independently of other patches
the resultant kernel requires further patches to successfully
use onboard devices, including the onboard flash. Since these
patches are independent of this one they will be submitted
separately.

A defconfig is not included here because not all of
the required drivers are actually in the kernel.
We intend to provide one as soon as the patches
will be incorporated in mainstream.

This patch is the combined work of nslu2-linux.org

Signed-off-by: John Bowler <jbowler@acm.org>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-ixp4xx/Kconfig

@@ -8,6 +8,16 @@ menu "Intel IXP4xx Implementation Options"
 
 comment "IXP4xx Platforms"
 
+# This entry is placed on top because otherwise it would have
+# been shown as a submenu.
+config MACH_NSLU2
+	bool
+	prompt "NSLU2" if !(MACH_IXDP465 || MACH_IXDPG425 || ARCH_IXDP425 || ARCH_ADI_COYOTE || ARCH_AVILA || ARCH_IXCDP1100 || ARCH_PRPMC1100 || MACH_GTWX5715)
+	help
+	  Say 'Y' here if you want your kernel to support Linksys's
+	  NSLU2 NAS device. For more information on this platform,
+	  see http://www.nslu2-linux.org
+
 config ARCH_AVILA
 	bool "Avila"
 	help

arch/arm/mach-ixp4xx/Makefile

@@ -8,4 +8,5 @@ obj-$(CONFIG_ARCH_IXDP4XX)	+= ixdp425-pci.o ixdp425-setup.o
 obj-$(CONFIG_MACH_IXDPG425)	+= ixdpg425-pci.o coyote-setup.o
 obj-$(CONFIG_ARCH_ADI_COYOTE)	+= coyote-pci.o coyote-setup.o
 obj-$(CONFIG_MACH_GTWX5715)	+= gtwx5715-pci.o gtwx5715-setup.o
+obj-$(CONFIG_MACH_NSLU2)	+= nslu2-pci.o nslu2-setup.o nslu2-power.o
 

arch/arm/mach-ixp4xx/nslu2-pci.c

@@ -0,0 +1,77 @@
+/*
+ * arch/arm/mach-ixp4xx/nslu2-pci.c
+ *
+ * NSLU2 board-level PCI initialization
+ *
+ * based on ixdp425-pci.c:
+ *	Copyright (C) 2002 Intel Corporation.
+ *	Copyright (C) 2003-2004 MontaVista Software, Inc.
+ *
+ * Maintainer: http://www.nslu2-linux.org/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+
+#include <asm/mach/pci.h>
+#include <asm/mach-types.h>
+
+void __init nslu2_pci_preinit(void)
+{
+	set_irq_type(IRQ_NSLU2_PCI_INTA, IRQT_LOW);
+	set_irq_type(IRQ_NSLU2_PCI_INTB, IRQT_LOW);
+	set_irq_type(IRQ_NSLU2_PCI_INTC, IRQT_LOW);
+
+	gpio_line_isr_clear(NSLU2_PCI_INTA_PIN);
+	gpio_line_isr_clear(NSLU2_PCI_INTB_PIN);
+	gpio_line_isr_clear(NSLU2_PCI_INTC_PIN);
+
+	/* INTD is not configured as GPIO is used
+	 * for the power input button.
+	 */
+
+	ixp4xx_pci_preinit();
+}
+
+static int __init nslu2_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
+{
+	static int pci_irq_table[NSLU2_PCI_IRQ_LINES] = {
+		IRQ_NSLU2_PCI_INTA,
+		IRQ_NSLU2_PCI_INTB,
+		IRQ_NSLU2_PCI_INTC,
+	};
+
+	int irq = -1;
+
+	if (slot >= 1 && slot <= NSLU2_PCI_MAX_DEV &&
+		pin >= 1 && pin <= NSLU2_PCI_IRQ_LINES) {
+			irq = pci_irq_table[(slot + pin - 2) % NSLU2_PCI_IRQ_LINES];
+	}
+
+	return irq;
+}
+
+struct hw_pci __initdata nslu2_pci = {
+	.nr_controllers = 1,
+	.preinit	= nslu2_pci_preinit,
+	.swizzle	= pci_std_swizzle,
+	.setup		= ixp4xx_setup,
+	.scan		= ixp4xx_scan_bus,
+	.map_irq	= nslu2_map_irq,
+};
+
+int __init nslu2_pci_init(void) /* monkey see, monkey do */
+{
+	if (machine_is_nslu2())
+		pci_common_init(&nslu2_pci);
+
+	return 0;
+}
+
+subsys_initcall(nslu2_pci_init);

arch/arm/mach-ixp4xx/nslu2-power.c

@@ -0,0 +1,92 @@
+/*
+ * arch/arm/mach-ixp4xx/nslu2-power.c
+ *
+ * NSLU2 Power/Reset driver
+ *
+ * Copyright (C) 2005 Tower Technologies
+ *
+ * based on nslu2-io.c
+ *  Copyright (C) 2004 Karen Spearel
+ *
+ * Author: Alessandro Zummo <a.zummo@towertech.it>
+ * Maintainers: http://www.nslu2-linux.org/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/reboot.h>
+#include <linux/interrupt.h>
+
+#include <asm/mach-types.h>
+
+extern void ctrl_alt_del(void);
+
+static irqreturn_t nslu2_power_handler(int irq, void *dev_id, struct pt_regs *regs)
+{
+	/* Signal init to do the ctrlaltdel action, this will bypass init if
+	 * it hasn't started and do a kernel_restart.
+	 */
+	ctrl_alt_del();
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t nslu2_reset_handler(int irq, void *dev_id, struct pt_regs *regs)
+{
+	/* This is the paper-clip reset, it shuts the machine down directly.
+	 */
+	machine_power_off();
+
+	return IRQ_HANDLED;
+}
+
+static int __init nslu2_power_init(void)
+{
+	if (!(machine_is_nslu2()))
+		return 0;
+
+	*IXP4XX_GPIO_GPISR = 0x20400000;	/* read the 2 irqs to clr */
+
+	set_irq_type(NSLU2_RB_IRQ, IRQT_LOW);
+	set_irq_type(NSLU2_PB_IRQ, IRQT_HIGH);
+
+	gpio_line_isr_clear(NSLU2_RB_GPIO);
+	gpio_line_isr_clear(NSLU2_PB_GPIO);
+
+	if (request_irq(NSLU2_RB_IRQ, &nslu2_reset_handler,
+		SA_INTERRUPT, "NSLU2 reset button", NULL) < 0) {
+
+		printk(KERN_DEBUG "Reset Button IRQ %d not available\n",
+			NSLU2_RB_IRQ);
+
+		return -EIO;
+	}
+
+	if (request_irq(NSLU2_PB_IRQ, &nslu2_power_handler,
+		SA_INTERRUPT, "NSLU2 power button", NULL) < 0) {
+
+		printk(KERN_DEBUG "Power Button IRQ %d not available\n",
+			NSLU2_PB_IRQ);
+
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static void __exit nslu2_power_exit(void)
+{
+	free_irq(NSLU2_RB_IRQ, NULL);
+	free_irq(NSLU2_PB_IRQ, NULL);
+}
+
+module_init(nslu2_power_init);
+module_exit(nslu2_power_exit);
+
+MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
+MODULE_DESCRIPTION("NSLU2 Power/Reset driver");
+MODULE_LICENSE("GPL");

arch/arm/mach-ixp4xx/nslu2-setup.c

@@ -0,0 +1,134 @@
+/*
+ * arch/arm/mach-ixp4xx/nslu2-setup.c
+ *
+ * NSLU2 board-setup
+ *
+ * based ixdp425-setup.c:
+ *      Copyright (C) 2003-2004 MontaVista Software, Inc.
+ *
+ * Author: Mark Rakes <mrakes at mac.com>
+ * Maintainers: http://www.nslu2-linux.org/
+ *
+ * Fixed missing init_time in MACHINE_START kas11 10/22/04
+ * Changed to conform to new style __init ixdp425 kas11 10/22/04
+ */
+
+#include <linux/kernel.h>
+#include <linux/serial.h>
+#include <linux/serial_8250.h>
+
+#include <asm/mach-types.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/flash.h>
+
+static struct flash_platform_data nslu2_flash_data = {
+	.map_name		= "cfi_probe",
+	.width			= 2,
+};
+
+static struct resource nslu2_flash_resource = {
+	.start			= NSLU2_FLASH_BASE,
+	.end			= NSLU2_FLASH_BASE + NSLU2_FLASH_SIZE,
+	.flags			= IORESOURCE_MEM,
+};
+
+static struct platform_device nslu2_flash = {
+	.name			= "IXP4XX-Flash",
+	.id			= 0,
+	.dev.platform_data	= &nslu2_flash_data,
+	.num_resources		= 1,
+	.resource		= &nslu2_flash_resource,
+};
+
+static struct ixp4xx_i2c_pins nslu2_i2c_gpio_pins = {
+	.sda_pin		= NSLU2_SDA_PIN,
+	.scl_pin		= NSLU2_SCL_PIN,
+};
+
+static struct platform_device nslu2_i2c_controller = {
+	.name			= "IXP4XX-I2C",
+	.id			= 0,
+	.dev.platform_data	= &nslu2_i2c_gpio_pins,
+	.num_resources		= 0,
+};
+
+static struct resource nslu2_uart_resources[] = {
+	{
+		.start		= IXP4XX_UART1_BASE_PHYS,
+		.end		= IXP4XX_UART1_BASE_PHYS + 0x0fff,
+		.flags		= IORESOURCE_MEM,
+	},
+	{
+		.start		= IXP4XX_UART2_BASE_PHYS,
+		.end		= IXP4XX_UART2_BASE_PHYS + 0x0fff,
+		.flags		= IORESOURCE_MEM,
+	}
+};
+
+static struct plat_serial8250_port nslu2_uart_data[] = {
+	{
+		.mapbase	= IXP4XX_UART1_BASE_PHYS,
+		.membase	= (char *)IXP4XX_UART1_BASE_VIRT + REG_OFFSET,
+		.irq		= IRQ_IXP4XX_UART1,
+		.flags		= UPF_BOOT_AUTOCONF,
+		.iotype		= UPIO_MEM,
+		.regshift	= 2,
+		.uartclk	= IXP4XX_UART_XTAL,
+	},
+	{
+		.mapbase	= IXP4XX_UART2_BASE_PHYS,
+		.membase	= (char *)IXP4XX_UART2_BASE_VIRT + REG_OFFSET,
+		.irq		= IRQ_IXP4XX_UART2,
+		.flags		= UPF_BOOT_AUTOCONF,
+		.iotype		= UPIO_MEM,
+		.regshift	= 2,
+		.uartclk	= IXP4XX_UART_XTAL,
+	},
+	{ }
+};
+
+static struct platform_device nslu2_uart = {
+	.name			= "serial8250",
+	.id			= PLAT8250_DEV_PLATFORM,
+	.dev.platform_data	= nslu2_uart_data,
+	.num_resources		= 2,
+	.resource		= nslu2_uart_resources,
+};
+
+static struct platform_device *nslu2_devices[] __initdata = {
+	&nslu2_i2c_controller,
+	&nslu2_flash,
+	&nslu2_uart,
+};
+
+static void nslu2_power_off(void)
+{
+	/* This causes the box to drop the power and go dead. */
+
+	/* enable the pwr cntl gpio */
+	gpio_line_config(NSLU2_PO_GPIO, IXP4XX_GPIO_OUT);
+
+	/* do the deed */
+	gpio_line_set(NSLU2_PO_GPIO, IXP4XX_GPIO_HIGH);
+}
+
+static void __init nslu2_init(void)
+{
+	ixp4xx_sys_init();
+
+	pm_power_off = nslu2_power_off;
+
+	platform_add_devices(nslu2_devices, ARRAY_SIZE(nslu2_devices));
+}
+
+MACHINE_START(NSLU2, "Linksys NSLU2")
+	/* Maintainer: www.nslu2-linux.org */
+	.phys_ram	= PHYS_OFFSET,
+	.phys_io	= IXP4XX_PERIPHERAL_BASE_PHYS,
+	.io_pg_offst	= ((IXP4XX_PERIPHERAL_BASE_VIRT) >> 18) & 0xFFFC,
+	.boot_params	= 0x00000100,
+	.map_io		= ixp4xx_map_io,
+	.init_irq	= ixp4xx_init_irq,
+	.timer          = &ixp4xx_timer,
+	.init_machine	= nslu2_init,
+MACHINE_END

include/asm-arm/arch-ixp4xx/hardware.h

@@ -44,5 +44,6 @@ extern unsigned int processor_id;
 #include "ixdp425.h"
 #include "coyote.h"
 #include "prpmc1100.h"
+#include "nslu2.h"
 
 #endif  /* _ASM_ARCH_HARDWARE_H */

include/asm-arm/arch-ixp4xx/irqs.h

@@ -93,4 +93,11 @@
 #define	IRQ_COYOTE_PCI_SLOT1	IRQ_IXP4XX_GPIO11
 #define	IRQ_COYOTE_IDE		IRQ_IXP4XX_GPIO5
 
+/*
+ * NSLU2 board IRQs
+ */
+#define        IRQ_NSLU2_PCI_INTA      IRQ_IXP4XX_GPIO11
+#define        IRQ_NSLU2_PCI_INTB      IRQ_IXP4XX_GPIO10
+#define        IRQ_NSLU2_PCI_INTC      IRQ_IXP4XX_GPIO9
+
 #endif