x86/mm: Add support for the non-standard protected e820 type

[deliverable/linux.git] / arch / x86 / include / uapi / asm / e820.h

diff --git a/arch/x86/include/uapi/asm/e820.h b/arch/x86/include/uapi/asm/e820.h
index d993e33f523654cf5a985481d62e60810830f66b..960a8a9dc4abafa0326f3822aee80c3c9764af93 100644 (file)
--- a/arch/x86/include/uapi/asm/e820.h
+++ b/arch/x86/include/uapi/asm/e820.h
@@ -33,6 +33,16 @@
 #define E820_NVS       4
 #define E820_UNUSABLE  5
 
+/*
+ * This is a non-standardized way to represent ADR or NVDIMM regions that
+ * persist over a reboot.  The kernel will ignore their special capabilities
+ * unless the CONFIG_X86_PMEM_LEGACY=y option is set.
+ *
+ * ( Note that older platforms also used 6 for the same type of memory,
+ *   but newer versions switched to 12 as 6 was assigned differently.  Some
+ *   time they will learn... )
+ */
+#define E820_PRAM      12
 
 /*
  * reserved RAM used by kernel itself