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diff --git a/arch/arm64/include/asm/pgtable-2level-hwdef.h b/arch/arm64/include/asm/pgtable-2level-hwdef.h
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+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_PGTABLE_2LEVEL_HWDEF_H
+#define __ASM_PGTABLE_2LEVEL_HWDEF_H
+
+/*
+ * With LPAE and 64KB pages, there are 2 levels of page tables. Each level has
+ * 8192 entries of 8 bytes each, occupying a 64KB page. Levels 0 and 1 are not
+ * used. The 2nd level table (PGD for Linux) can cover a range of 4TB, each
+ * entry representing 512MB. The user and kernel address spaces are limited to
+ * 512GB and therefore we only use 1024 entries in the PGD.
+ */
+#define PTRS_PER_PTE 8192
+#define PTRS_PER_PGD 1024
+
+/*
+ * PGDIR_SHIFT determines the size a top-level page table entry can map.
+ */
+#define PGDIR_SHIFT 29
+#define PGDIR_SIZE (_AC(1, UL) << PGDIR_SHIFT)
+#define PGDIR_MASK (~(PGDIR_SIZE-1))
+
+/*
+ * section address mask and size definitions.
+ */
+#define SECTION_SHIFT 29
+#define SECTION_SIZE (_AC(1, UL) << SECTION_SHIFT)
+#define SECTION_MASK (~(SECTION_SIZE-1))
+
+#endif