};
 
 extern int find_unisys_acpi_oem_table(unsigned long *oem_addr);
+extern void unmap_unisys_acpi_oem_table(unsigned long oem_addr);
 #endif
 
 struct mip_reg {
 }
 
 #ifdef CONFIG_ACPI
-int __init
-find_unisys_acpi_oem_table(unsigned long *oem_addr)
+static unsigned long oem_addrX;
+static unsigned long oem_size;
+int __init find_unisys_acpi_oem_table(unsigned long *oem_addr)
 {
        struct acpi_table_header *header = NULL;
        int i = 0;
-       while (ACPI_SUCCESS(acpi_get_table("OEM1", i++, &header))) {
+       acpi_size tbl_size;
+
+       while (ACPI_SUCCESS(acpi_get_table_with_size("OEM1", i++, &header, &tbl_size))) {
                if (!memcmp((char *) &header->oem_id, "UNISYS", 6)) {
                        struct oem_table *t = (struct oem_table *)header;
-                       *oem_addr = (unsigned long)__acpi_map_table(t->OEMTableAddr,
-                                                                   t->OEMTableSize);
+
+                       oem_addrX = t->OEMTableAddr;
+                       oem_size = t->OEMTableSize;
+                       early_acpi_os_unmap_memory(header, tbl_size);
+
+                       *oem_addr = (unsigned long)__acpi_map_table(oem_addrX,
+                                                                   oem_size);
                        return 0;
                }
+               early_acpi_os_unmap_memory(header, tbl_size);
        }
        return -1;
 }
+
+void __init unmap_unisys_acpi_oem_table(unsigned long oem_addr)
+{
+       if (!oem_addr)
+               return;
+
+       __acpi_unmap_table((char *)oem_addr, oem_size);
+}
 #endif
 
 static void
 
 /* Hook from generic ACPI tables.c */
 static int __init acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 {
-       unsigned long oem_addr;
+       unsigned long oem_addr = 0;
+       int check_dsdt;
+       int ret = 0;
+
+       /* check dsdt at first to avoid clear fix_map for oem_addr */
+       check_dsdt = es7000_check_dsdt();
+
        if (!find_unisys_acpi_oem_table(&oem_addr)) {
-               if (es7000_check_dsdt())
-                       return parse_unisys_oem((char *)oem_addr);
+               if (check_dsdt)
+                       ret = parse_unisys_oem((char *)oem_addr);
                else {
                        setup_unisys();
-                       return 1;
+                       ret = 1;
                }
+               /*
+                * we need to unmap it
+                */
+               unmap_unisys_acpi_oem_table(oem_addr);
        }
-       return 0;
+       return ret;
 }
 #else
 static int __init acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 
 
 extern int parse_unisys_oem (char *oemptr);
 extern int find_unisys_acpi_oem_table(unsigned long *oem_addr);
+extern void unmap_unisys_acpi_oem_table(unsigned long oem_addr);
 extern void setup_unisys(void);
 
 #ifndef CONFIG_X86_GENERICARCH