x86: Support QEMU x86 targets

This commit introduces the initial U-Boot support for QEMU x86 targets.
U-Boot can boot from coreboot as a payload, or directly without coreboot.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
Merged in patch 'x86: qemu: Add CMD_NET to qemu-x86_defconfig
   https://patchwork.ozlabs.org/patch/479745/
diff --git a/arch/x86/cpu/qemu/pci.c b/arch/x86/cpu/qemu/pci.c
new file mode 100644
index 0000000..d50ab75
--- /dev/null
+++ b/arch/x86/cpu/qemu/pci.c
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <pci.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+void board_pci_setup_hose(struct pci_controller *hose)
+{
+	hose->first_busno = 0;
+	hose->last_busno = 0;
+
+	/* PCI memory space */
+	pci_set_region(hose->regions + 0,
+		       CONFIG_PCI_MEM_BUS,
+		       CONFIG_PCI_MEM_PHYS,
+		       CONFIG_PCI_MEM_SIZE,
+		       PCI_REGION_MEM);
+
+	/* PCI IO space */
+	pci_set_region(hose->regions + 1,
+		       CONFIG_PCI_IO_BUS,
+		       CONFIG_PCI_IO_PHYS,
+		       CONFIG_PCI_IO_SIZE,
+		       PCI_REGION_IO);
+
+	pci_set_region(hose->regions + 2,
+		       CONFIG_PCI_PREF_BUS,
+		       CONFIG_PCI_PREF_PHYS,
+		       CONFIG_PCI_PREF_SIZE,
+		       PCI_REGION_PREFETCH);
+
+	pci_set_region(hose->regions + 3,
+		       0,
+		       0,
+		       gd->ram_size,
+		       PCI_REGION_MEM | PCI_REGION_SYS_MEMORY);
+
+	hose->region_count = 4;
+}
+
+int board_pci_post_scan(struct pci_controller *hose)
+{
+	return 0;
+}