ARM: 6206/1: CONFIG_FORCE_MAX_ZONEORDER update for SH-Mobile ARM

Allow SH-Mobile ARM users to adjust FORCE_MAX_ZONEORDER.

The Kconfig entry is taken from SH and non-4K page size
stuff has been trimmed away. For now only SH-Mobile ARM is
allowed to change this variable, SA1111 configs are kept at
"9" and the rest at "11".

CONFIG_FORCE_MAX_ZONEORDER lets the user tweak the maximum
amount of physically contiguous memory that can be allocated
by the kernel.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 16 insertions, 5 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index aa738aa70c7..5f3a9da6da0 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1031,11 +1031,6 @@ endmenu
 
 source "arch/arm/common/Kconfig"
 
-config FORCE_MAX_ZONEORDER
-        int
-        depends on SA1111
-        default "9"
-
 menu "Bus support"
 
 config ARM_AMBA
@@ -1304,6 +1299,22 @@ config SPARSE_IRQ
 
 source "mm/Kconfig"
 
+config FORCE_MAX_ZONEORDER
+        int "Maximum zone order" if ARCH_SHMOBILE
+        range 11 64 if ARCH_SHMOBILE
+        default "9" if SA1111
+        default "11"
+        help
+          The kernel memory allocator divides physically contiguous memory
+          blocks into "zones", where each zone is a power of two number of
+          pages.  This option selects the largest power of two that the kernel
+          keeps in the memory allocator.  If you need to allocate very large
+          blocks of physically contiguous memory, then you may need to
+          increase this value.
+
+          This config option is actually maximum order plus one. For example,
+          a value of 11 means that the largest free memory block is 2^10 pages.
+
 config LEDS
         bool "Timer and CPU usage LEDs"
         depends on ARCH_CDB89712 || ARCH_EBSA110 || \