dm: x86: Add a uclass for a Platform Controller Hub

Add a simple uclass for this chip which is often found in x86 systems
where the CPU is a separate device.

The device can have children, so make it scan the device tree for these.

Signed-off-by: Simon Glass <sjg@chromium.org>

arch/x86/cpu/ivybridge/bd82x6x.c

@@ -157,12 +157,3 @@ U_BOOT_DRIVER(bd82x6x_drv) = {
 	.of_match	= bd82x6x_ids,
 	.probe		= bd82x6x_probe,
 };
-
-/*
- * TODO(sjg@chromium.org): Move this to arch/x86/lib or similar when other
- * boards also use a PCH
- */
-UCLASS_DRIVER(pch) = {
-	.id		= UCLASS_PCH,
-	.name		= "pch",
-};

arch/x86/lib/Makefile

@@ -20,6 +20,7 @@ obj-$(CONFIG_SYS_PCAT_TIMER) += pcat_timer.o
 ifndef CONFIG_DM_PCI
 obj-$(CONFIG_PCI) += pci_type1.o
 endif
+obj-y	+= pch-uclass.o
 obj-y	+= relocate.o
 obj-y += physmem.o
 obj-$(CONFIG_X86_RAMTEST) += ramtest.o

arch/x86/lib/pch-uclass.c

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/root.h>
+
+static int pch_uclass_post_bind(struct udevice *bus)
+{
+	/*
+	 * Scan the device tree for devices
+	 *
+	 * Before relocation, only bind devices marked for pre-relocation
+	 * use.
+	 */
+	return dm_scan_fdt_node(bus, gd->fdt_blob, bus->of_offset,
+				gd->flags & GD_FLG_RELOC ? false : true);
+}
+
+UCLASS_DRIVER(pch) = {
+	.id		= UCLASS_PCH,
+	.name		= "pch",
+	.post_bind	= pch_uclass_post_bind,
+};