Merge tag 'v4.4.63' into linux-linaro-lsk-v4.4

[firefly-linux-kernel-4.4.55.git] / arch / arm64 / include / asm / kernel-pgtable.h

diff --git a/arch/arm64/include/asm/kernel-pgtable.h b/arch/arm64/include/asm/kernel-pgtable.h
index a459714ee29e38fbf81f2061026933736ed1cbfc..5c6375d8528bb8ddd313bfa2911f7a0d77819028 100644 (file)
--- a/arch/arm64/include/asm/kernel-pgtable.h
+++ b/arch/arm64/include/asm/kernel-pgtable.h
@@ -79,5 +79,17 @@
 #define SWAPPER_MM_MMUFLAGS    (PTE_ATTRINDX(MT_NORMAL) | SWAPPER_PTE_FLAGS)
 #endif
 
+/*
+ * To make optimal use of block mappings when laying out the linear
+ * mapping, round down the base of physical memory to a size that can
+ * be mapped efficiently, i.e., either PUD_SIZE (4k granule) or PMD_SIZE
+ * (64k granule), or a multiple that can be mapped using contiguous bits
+ * in the page tables: 32 * PMD_SIZE (16k granule)
+ */
+#ifdef CONFIG_ARM64_64K_PAGES
+#define ARM64_MEMSTART_ALIGN   SZ_512M
+#else
+#define ARM64_MEMSTART_ALIGN   SZ_1G
+#endif
 
 #endif /* __ASM_KERNEL_PGTABLE_H */