X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=arch%2Farm64%2Finclude%2Fasm%2Fkernel-pgtable.h;h=5c6375d8528bb8ddd313bfa2911f7a0d77819028;hb=10fd238c91a8dd2fb9c9bce99eb4d357254fb3c6;hp=a459714ee29e38fbf81f2061026933736ed1cbfc;hpb=665ddeb210c10f4daf8ffbe07072771c0020af3a;p=firefly-linux-kernel-4.4.55.git

diff --git a/arch/arm64/include/asm/kernel-pgtable.h b/arch/arm64/include/asm/kernel-pgtable.h
index a459714ee29e..5c6375d8528b 100644
--- 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 */