x86/PCI: read root resources from IOH on Intel

For intel systems with multi IOH, we should read peer root resources
directly from PCI config space, and don't trust _CRS.

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/arch/x86/pci/intel_bus.c b/arch/x86/pci/intel_bus.c
new file mode 100644
index 0000000..b7a55dc
--- /dev/null
+++ b/arch/x86/pci/intel_bus.c
@@ -0,0 +1,90 @@
+/*
+ * to read io range from IOH pci conf, need to do it after mmconfig is there
+ */
+
+#include <linux/delay.h>
+#include <linux/dmi.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <asm/pci_x86.h>
+
+#include "bus_numa.h"
+
+static inline void print_ioh_resources(struct pci_root_info *info)
+{
+	int res_num;
+	int busnum;
+	int i;
+
+	printk(KERN_DEBUG "IOH bus: [%02x, %02x]\n",
+			info->bus_min, info->bus_max);
+	res_num = info->res_num;
+	busnum = info->bus_min;
+	for (i = 0; i < res_num; i++) {
+		struct resource *res;
+
+		res = &info->res[i];
+		printk(KERN_DEBUG "IOH bus: %02x index %x %s: [%llx, %llx]\n",
+			busnum, i,
+			(res->flags & IORESOURCE_IO) ? "io port" :
+							"mmio",
+			res->start, res->end);
+	}
+}
+
+#define IOH_LIO			0x108
+#define IOH_LMMIOL		0x10c
+#define IOH_LMMIOH		0x110
+#define IOH_LMMIOH_BASEU	0x114
+#define IOH_LMMIOH_LIMITU	0x118
+#define IOH_LCFGBUS		0x11c
+
+static void __devinit pci_root_bus_res(struct pci_dev *dev)
+{
+	u16 word;
+	u32 dword;
+	struct pci_root_info *info;
+	u16 io_base, io_end;
+	u32 mmiol_base, mmiol_end;
+	u64 mmioh_base, mmioh_end;
+	int bus_base, bus_end;
+
+	if (pci_root_num >= PCI_ROOT_NR) {
+		printk(KERN_DEBUG "intel_bus.c: PCI_ROOT_NR is too small\n");
+		return;
+	}
+
+	info = &pci_root_info[pci_root_num];
+	pci_root_num++;
+
+	pci_read_config_word(dev, IOH_LCFGBUS, &word);
+	bus_base = (word & 0xff);
+	bus_end = (word & 0xff00) >> 8;
+	sprintf(info->name, "PCI Bus #%02x", bus_base);
+	info->bus_min = bus_base;
+	info->bus_max = bus_end;
+
+	pci_read_config_word(dev, IOH_LIO, &word);
+	io_base = (word & 0xf0) << (12 - 4);
+	io_end = (word & 0xf000) | 0xfff;
+	update_res(info, io_base, io_end, IORESOURCE_IO, 0);
+
+	pci_read_config_dword(dev, IOH_LMMIOL, &dword);
+	mmiol_base = (dword & 0xff00) << (24 - 8);
+	mmiol_end = (dword & 0xff000000) | 0xffffff;
+	update_res(info, mmiol_base, mmiol_end, IORESOURCE_MEM, 0);
+
+	pci_read_config_dword(dev, IOH_LMMIOH, &dword);
+	mmioh_base = ((u64)(dword & 0xfc00)) << (26 - 10);
+	mmioh_end = ((u64)(dword & 0xfc000000) | 0x3ffffff);
+	pci_read_config_dword(dev, IOH_LMMIOH_BASEU, &dword);
+	mmioh_base |= ((u64)(dword & 0x7ffff)) << 32;
+	pci_read_config_dword(dev, IOH_LMMIOH_LIMITU, &dword);
+	mmioh_end |= ((u64)(dword & 0x7ffff)) << 32;
+	update_res(info, mmioh_base, mmioh_end, IORESOURCE_MEM, 0);
+
+	print_ioh_resources(info);
+}
+
+/* intel IOH */
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x342e, pci_root_bus_res);