s390: make MAX_PHYSMEM_BITS configurable

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index fc842c4bd7204e1b64e64b6c0a0af95ffcb9667a..afac5d89ad1f989a0c90552725f234fa3f17f5cd 100644 (file)
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -537,6 +537,16 @@ config FORCE_MAX_ZONEORDER
 
 source "mm/Kconfig"
 
+config MAX_PHYSMEM_BITS
+       int "Maximum size of supported physical memory in bits (42-53)"
+       range 42 53
+       default "46"
+       help
+         This option specifies the maximum supported size of physical memory
+         in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
+         Increasing the number of bits also increases the kernel image size.
+         By default 46 bits (64TB) are supported.
+
 config PACK_STACK
        def_bool y
        prompt "Pack kernel stack"

diff --git a/arch/s390/include/asm/sparsemem.h b/arch/s390/include/asm/sparsemem.h
index 487428b6d099435a45dde19777a84b542b6e677d..334e279f1bcebde5ce82f39cede162574d3e3708 100644 (file)
--- a/arch/s390/include/asm/sparsemem.h
+++ b/arch/s390/include/asm/sparsemem.h
@@ -2,6 +2,6 @@
 #define _ASM_S390_SPARSEMEM_H
 
 #define SECTION_SIZE_BITS      28
-#define MAX_PHYSMEM_BITS       46
+#define MAX_PHYSMEM_BITS       CONFIG_MAX_PHYSMEM_BITS
 
 #endif /* _ASM_S390_SPARSEMEM_H */