Save/restore the registers used in __mmu_cache_* so that they can
be called as regular C functions.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

To let the linker remove unused functions.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Traditionally we call __mmu_cache_flush in early startup. There
is a problem with armv7 and hierarchical caches though, on these
systems __mmu_cache_flush uses the stack. Appearantly this was
seldomly a problem, because most of these systems have a ROM
bootloader which sets up some stack, but on a special i.MX6 system
this failed badly. We should not have to flush caches here. Every
sane system should pass control to the bootloader without stale
entries in the caches *), so it should be a safe assumption that the
cache flush can be removed.

Since __mmu_cache_flush is not called from early code anymore we can
also move it to the regular text section.

Be brave and give it a try.

*) omap3 seems to be a exception to this, but this has a cache flush
in arch_init_lowlevel already

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

and make init.h availlable for assembly too

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Instead of having seperate cache flush functions in the startup code
we want to call the generic functions. To accomplish this they have
to be in the bare_init section.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

This is a preparation to add second level cache support.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

These cache functions have been extracted from
arch/arm/boot/compressed/head.S. The old code only worked
properly on ARMv4. Tested on ARMv4, ARMv5, ARMv6 hardware.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>