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Diffstat (limited to 'arch/arm64/include/asm/pgtable-3level-hwdef.h')
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diff --git a/arch/arm64/include/asm/pgtable-3level-hwdef.h b/arch/arm64/include/asm/pgtable-3level-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_3LEVEL_HWDEF_H
+#define __ASM_PGTABLE_3LEVEL_HWDEF_H
+
+/*
+ * With LPAE and 4KB pages, there are 3 levels of page tables. Each level has
+ * 512 entries of 8 bytes each, occupying a 4K page. The first level table
+ * covers a range of 512GB, each entry representing 1GB. The user and kernel
+ * address spaces are limited to 512GB each.
+ */
+#define PTRS_PER_PTE 512
+#define PTRS_PER_PMD 512
+#define PTRS_PER_PGD 512
+
+/*
+ * PGDIR_SHIFT determines the size a top-level page table entry can map.
+ */
+#define PGDIR_SHIFT 30
+#define PGDIR_SIZE (_AC(1, UL) << PGDIR_SHIFT)
+#define PGDIR_MASK (~(PGDIR_SIZE-1))
+
+/*
+ * PMD_SHIFT determines the size a middle-level page table entry can map.
+ */
+#define PMD_SHIFT 21
+#define PMD_SIZE (_AC(1, UL) << PMD_SHIFT)
+#define PMD_MASK (~(PMD_SIZE-1))
+
+/*
+ * section address mask and size definitions.
+ */
+#define SECTION_SHIFT 21
+#define SECTION_SIZE (_AC(1, UL) << SECTION_SHIFT)
+#define SECTION_MASK (~(SECTION_SIZE-1))
+
+#endif