sh: Add fixed ioremap support

Some devices need to be ioremap'd and accessed very early in the boot
process. It is not possible to use the standard ioremap() function in
this case because that requires kmalloc()'ing some virtual address space
and kmalloc() may not be available so early in boot.

This patch provides fixmap mappings that allow physical address ranges
to be remapped into the kernel address space during the early boot
stages.

Signed-off-by: Matt Fleming <matt@console-pimps.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig
index 7a4ebc8cbadd..b89075256b70 100644
--- a/arch/sh/mm/Kconfig
+++ b/arch/sh/mm/Kconfig
@@ -169,6 +169,10 @@ config ARCH_MEMORY_PROBE
         def_bool y
         depends on MEMORY_HOTPLUG
 
+config IOREMAP_FIXED
+       def_bool y
+       depends on X2TLB || SUPERH64
+
 choice
         prompt "Kernel page size"
         default PAGE_SIZE_4KB