[ARM] 4874/2: ixp4xx: Add support for the Freecom FSG-3 board

The Freecom-FSG3 is a small network-attached-storage device with the
following feature set:

* Intel IXP422
* 4MB Flash (ixp4xx flash driver)
* 64MB RAM
* 4 USB 2.0 host ports (ehci and ohci drivers)
* 1 WAN (eth1) and 3 LAN (eth0) ethernet ports
  * Supported by the open source ixp4xx ethernet driver
* Via VT6421 disk controller (libata and sata-via drivers)
  * Internal hard disk (PATA supported, SATA not yet supported)
  * External SATA port (not yet supported)
* ISL1208 RTC chip
* Winbond 83782 temp sensor and fan controller
* MiniPCI slot

The ixp4xx_defconfig is also updated to support this device (the
leds-fsg driver is to be submitted separately via the leds tree after
this initial support is merged, as it depends on header gpio defines).

Signed-off-by: Rod Whitby <rod@whitby.id.au>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-ixp4xx/fsg-pci.c b/arch/arm/mach-ixp4xx/fsg-pci.c
new file mode 100644
index 0000000..f19f3f6
--- /dev/null
+++ b/arch/arm/mach-ixp4xx/fsg-pci.c
@@ -0,0 +1,71 @@
+/*
+ * arch/arch/mach-ixp4xx/fsg-pci.c
+ *
+ * FSG board-level PCI initialization
+ *
+ * Author: Rod Whitby <rod@whitby.id.au>
+ * Maintainer: http://www.nslu2-linux.org/
+ *
+ * based on ixdp425-pci.c:
+ *	Copyright (C) 2002 Intel Corporation.
+ *	Copyright (C) 2003-2004 MontaVista Software, Inc.
+ *
+ * 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/pci.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+
+#include <asm/mach/pci.h>
+#include <asm/mach-types.h>
+
+void __init fsg_pci_preinit(void)
+{
+	set_irq_type(IRQ_FSG_PCI_INTA, IRQT_LOW);
+	set_irq_type(IRQ_FSG_PCI_INTB, IRQT_LOW);
+	set_irq_type(IRQ_FSG_PCI_INTC, IRQT_LOW);
+
+	ixp4xx_pci_preinit();
+}
+
+static int __init fsg_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
+{
+	static int pci_irq_table[FSG_PCI_IRQ_LINES] = {
+		IRQ_FSG_PCI_INTC,
+		IRQ_FSG_PCI_INTB,
+		IRQ_FSG_PCI_INTA,
+	};
+
+	int irq = -1;
+	slot = slot - 11;
+
+	if (slot >= 1 && slot <= FSG_PCI_MAX_DEV &&
+	    pin >= 1 && pin <= FSG_PCI_IRQ_LINES)
+		irq = pci_irq_table[(slot - 1)];
+	printk(KERN_INFO "%s: Mapped slot %d pin %d to IRQ %d\n",
+	       __func__, slot, pin, irq);
+
+	return irq;
+}
+
+struct hw_pci fsg_pci __initdata = {
+	.nr_controllers = 1,
+	.preinit =	  fsg_pci_preinit,
+	.swizzle =	  pci_std_swizzle,
+	.setup =	  ixp4xx_setup,
+	.scan =		  ixp4xx_scan_bus,
+	.map_irq =	  fsg_map_irq,
+};
+
+int __init fsg_pci_init(void)
+{
+	if (machine_is_fsg())
+		pci_common_init(&fsg_pci);
+	return 0;
+}
+
+subsys_initcall(fsg_pci_init);