From f360277f2f931a48c07f9e4ebf84cd712abd83a5 Mon Sep 17 00:00:00 2001
From: liangliang-quan <liangliang.quan@pt.sony.com.cn>
Date: Tue, 18 Feb 2014 10:12:00 +0800
Subject: [PATCH] Create fake ivmd table to make via xhci work on
 GA-F2A88X-UP4

---
 drivers/iommu/amd_iommu_init.c |   33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 28b4bea..1c762be 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -33,6 +33,7 @@
 #include <asm/iommu_table.h>
 #include <asm/io_apic.h>
 #include <asm/irq_remapping.h>
+#include <asm/e820.h>
 
 #include "amd_iommu_proto.h"
 #include "amd_iommu_types.h"
@@ -1492,6 +1493,9 @@ static int __init init_memory_definitions(struct acpi_table_header *table)
 {
 	u8 *p = (u8 *)table, *end = (u8 *)table;
 	struct ivmd_header *m;
+	struct ivmd_header via_xhci;
+	int map_areas = 0;
+	int reserved_areas = 0;
 
 	end += table->length;
 	p += IVRS_HEADER_LENGTH;
@@ -1506,6 +1510,35 @@ static int __init init_memory_definitions(struct acpi_table_header *table)
 		p += m->length;
 	}
 
+	/*
+	 * Create fake ivmd table for via_xhci.
+	 * VIA XHCI on GA-F2A88X-UP4 directly accesses address of reserved area
+	 * which leads to IOMMU attempts to translate this phy address as
+	 * a virtual address, then IO_PAGE_FAULT occurs.
+	 * This phy address should not be translated by IOMMU, but ACPI
+	 * does not excludes it.
+	 * We create a fake ivmd table to exclude this area.
+	 * Then VIA XHCI can work.
+	*/
+	via_xhci.type = ACPI_IVMD_TYPE;
+	via_xhci.flags = IVMD_FLAG_EXCL_RANGE;
+	via_xhci.length = 32;
+	/* device id of VIA XHCI */
+	via_xhci.devid = 0x0300;
+	/* iter all the map areas to find the 3rd reserved area */
+	for (map_areas = 0; map_areas < e820_saved.nr_map; map_areas++) {
+		if (e820_saved.map[map_areas].type == E820_RESERVED) {
+			reserved_areas++;
+		}
+		/* the address varies but always in the 3rd reserved area */
+		if (reserved_areas == 3) {
+			via_xhci.range_start = e820_saved.map[map_areas].addr;
+			via_xhci.range_length = e820_saved.map[map_areas].size;
+			init_exclusion_range(&via_xhci);
+			break;
+		}
+	}
+
 	return 0;
 }
 
-- 
1.7.9.5