|author||Michal Simek <firstname.lastname@example.org>||2011-12-15 15:02:37 +0100|
|committer||Michal Simek <email@example.com>||2012-03-23 09:28:13 +0100|
microblaze: Highmem support
The first highmem implementation. Signed-off-by: Michal Simek <firstname.lastname@example.org>
Diffstat (limited to 'arch/microblaze/Kconfig')
1 files changed, 11 insertions, 13 deletions
diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index 3267cc5065d..86ae27871f4 100644
@@ -159,20 +159,18 @@ config XILINX_UNCACHED_SHADOW
The feature requires the design to define the RAM memory controller
window to be twice as large as the actual physical memory.
- bool "Set high memory pool address"
- depends on ADVANCED_OPTIONS && HIGHMEM
- This option allows you to set the base address of the kernel virtual
- area used to map high memory pages. This can be useful in
- optimizing the layout of kernel virtual memory.
- Say N here unless you know what you are doing.
- hex "Virtual start address of high memory pool" if HIGHMEM_START_BOOL
+ bool "High memory support"
depends on MMU
- default "0xfe000000"
+ The address space of Microblaze processors is only 4 Gigabytes large
+ and it has to accommodate user address space, kernel address
+ space as well as some memory mapped IO. That means that, if you
+ have a large amount of physical memory and/or IO, not all of the
+ memory can be "permanently mapped" by the kernel. The physical
+ memory that is not permanently mapped is called "high memory".
+ If unsure, say n.
bool "Set maximum low memory"