1 files changed, 24 insertions, 0 deletions

diff --git a/include/asm-x86/gart.h b/include/asm-x86/gart.h
index 6f22786d2f0c..c818b96f936b 100644
--- a/include/asm-x86/gart.h
+++ b/include/asm-x86/gart.h
@@ -1,6 +1,8 @@
 #ifndef _ASM_X8664_IOMMU_H
 #define _ASM_X8664_IOMMU_H 1
 
+#include <asm/e820.h>
+
 extern void pci_iommu_shutdown(void);
 extern void no_iommu_init(void);
 extern int force_iommu, no_iommu;
@@ -69,4 +71,26 @@ static inline void enable_gart_translation(struct pci_dev *dev, u64 addr)
         pci_write_config_dword(dev, AMD64_GARTAPERTURECTL, ctl);
 }
 
+static inline int aperture_valid(u64 aper_base, u32 aper_size, u32 min_size)
+{
+        if (!aper_base)
+                return 0;
+
+        if (aper_base + aper_size > 0x100000000ULL) {
+                printk(KERN_ERR "Aperture beyond 4GB. Ignoring.\n");
+                return 0;
+        }
+        if (e820_any_mapped(aper_base, aper_base + aper_size, E820_RAM)) {
+                printk(KERN_ERR "Aperture pointing to e820 RAM. Ignoring.\n");
+                return 0;
+        }
+        if (aper_size < min_size) {
+                printk(KERN_ERR "Aperture too small (%d MB) than (%d MB)\n",
+                                 aper_size>>20, min_size>>20);
+                return 0;
+        }
+
+        return 1;
+}
+
 #endif