Commit Graph

9 Commits

Author SHA1 Message Date
Simon Glass 0dde7f5379 arm: Add control over cachability of memory regions
Add support for adjusting the L1 cache behavior by updating the MMU
configuration. The mmu_set_region_dcache_behaviour() function allows
drivers to make these changes after the MMU is set up.

It is implemented only for ARMv7 at present.

This is needed for LCD support, where we want to make the LCD frame buffer
write-through (or off) rather than write-back.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2012-11-19 08:15:38 -07:00
SRICHARAN R d702b0811d ARM: cache: Move the cp15 CR register read before flushing the cache.
The following is the cleanup sequence in arch/arm/cpu/armv7/cpu.c

int cleanup_before_linux(void)
{
 ...
 ...
 dcache_disable();
 v7_outer_cache_disable();
 invalidate_dcache_all();
}

 1) invalidate_dcache_all call expects that all the caches has been
 flushed, invalidated and there are no dirty entries prior to its
 execution.  In the above sequence dcache_disable() flushes, invalidates
 the caches and turns off the  mmu. But after it cleanups the cache
 and before the mmu is disabled  there is a cp_delay() function which
 has STR instruction. On certain cores like the cortex-a15, cache hit
 and a write can happen to a cache line even when the dcache is
 disabled. So the above mentioned STR instruction creates a dirty entry
 after cleaning. The mmu gets disabled after this.

 2) invalidate_dcache_all invalidates the cache lines. Again on
 cores like cortex-a15, invalidate instruction flushes the dirty
 line as well. So some times the dirty line from sequence 1
 can corrupt the memory resulting in a crash.

 Fixing this by moving the get_cr() and cp_delay() calls before
 cleaning up the cache, thus avoiding the dirty entry.

Signed-off-by: R Sricharan <r.sricharan@ti.com>
2012-07-07 14:07:44 +02:00
Aneesh V e05f00792b arm: minor fixes for cache and mmu handling
1. make sure that page table setup is not done multiple times
2. flush_dcache_all() is more appropriate while disabling cache
   than a range flush on the entire memory(flush_cache())

   Provide a default implementation for flush_dcache_all()
   for backward compatibility and to avoid build issues.

Signed-off-by: Aneesh V <aneesh@ti.com>
2011-07-04 10:55:25 +02:00
Aneesh V c2dd0d4554 armv7: integrate cache maintenance support
- Enable I-cache on bootup
- Enable MMU and D-cache immediately after relocation
	- Do necessary initialization before enabling d-cache and MMU
- Changes to cleanup_before_linux()
	- Make changes according to the new framework

Signed-off-by: Aneesh V <aneesh@ti.com>
2011-07-04 10:55:25 +02:00
Aneesh V e47f2db537 armv7: rename cache related CONFIG flags
Replace the cache related CONFIG flags with more meaningful
names. Following are the changes:

CONFIG_L2_OFF	     -> CONFIG_SYS_L2CACHE_OFF
CONFIG_SYS_NO_ICACHE -> CONFIG_SYS_ICACHE_OFF
CONFIG_SYS_NO_DCACHE -> CONFIG_SYS_DCACHE_OFF

Signed-off-by: Aneesh V <aneesh@ti.com>
V2:
 * Changed CONFIG_L2_OFF -> CONFIG_SYS_NO_L2CACHE
V4:
 * Changed all three flags to the final names suggested as above
   and accordingly changed the commit message
2011-07-04 10:55:25 +02:00
Wolfgang Denk a9aa392629 Drop support for CONFIG_SYS_ARM_WITHOUT_RELOC
When this define was introduced, the idea was to provide a soft
migration path for ARM boards to get adapted to the new relocation
support.  However, other recent changes led to a different
implementation (ELF relocation), where this no longer works.  By now
CONFIG_SYS_ARM_WITHOUT_RELOC does not only not help any more, but it
actually hurts because it obfuscates the actual code by sprinkling it
with lots of dead and non-working debris.

So let's make a clean cut and drop CONFIG_SYS_ARM_WITHOUT_RELOC.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Tested-by: Heiko Schocher <hs@denx.de>
Tested-by: Reinhard Meyer <u-boot@emk-elektronik.de>
2010-10-29 21:39:59 +02:00
Heiko Schocher f1d2b313c9 ARM: add relocation support
!! This breaks support for all arm boards !!

To compile in old style, you must define
CONFIG_SYS_ARM_WITHOUT_RELOC or you can compile
with "CONFIG_SYS_ARM_WITHOUT_RELOC=1 ./MAKEALL board"

!! This define will be removed soon, so convert your
board to use relocation support

Portions of this work were supported by funding from
the CE Linux Forum.

Signed-off-by: Heiko Schocher <hs@denx.de>

Fix boot from NAND for non-ARM systems
Signed-off-by: Wolfgang Denk <wd@denx.de>
2010-09-19 19:29:53 +02:00
Heiko Schocher 880eff5cfb ARM: cp15: setup mmu and enable dcache
This has been tested on at91sam9263 and STN8815.
Again, I didn't check if it has bad effects
on non-arm926 cores.

Initially I had a "done" bit to only set up page tables
at the beginning. However, since the aligmnent requirement
was for the whole object file, this extra integer tool 16kB
in BSS, so I chose to remove it.

Also, note not all boards use PHYS_SDRAM, but it looks like
it's the most used name (more than CONFIG_SYS_DRAM_BASE for
example).

Portions of this work were supported by funding from
the CE Linux Forum.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Signed-off-by: Heiko Schocher <hs@denx.de>
2010-09-19 19:29:50 +02:00
Peter Tyser ea0364f1bb Move lib_$ARCH directories to arch/$ARCH/lib
Also move lib_$ARCH/config.mk to arch/$ARCH/config.mk

This change is intended to clean up the top-level directory structure
and more closely mimic Linux's directory organization.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
2010-04-13 09:13:03 +02:00