[U-Boot] [PATCH] ARM: Rework and correct barrier definitions

[Stephen Warren]

On 08/01/2016 04:54 PM, Tom Rini wrote:
> As part of testing booting Linux kernels on Rockchip devices, it was
> discovered by Ziyuan Xu and Sandy Patterson that we had multiple and for
> some cases incomplete isb definitions.  This was causing a failure to
> boot of the Linux kernel.
>
> In order to solve this problem as well as cover any corner cases that we
> may also have had a number of changes are made in order to consolidate
> things.  First, <asm/barriers.h> now becomes the source of isb/dsb/dmb
> definitions.  This however introduces another complexity.  Due to
> needing to build SPL for 32bit tegra with -march=armv4 we need to borrow
> the __LINUX_ARM_ARCH__ logic from the Linux Kernel in a more complete
> form.  Move this from arch/arm/lib/Makefile to arch/arm/Makefile and add
> a comment about it.  Now that we can always know what the target CPU is
> capable off we can get always do the correct thing for the barrier.  The
> final part of this is that need to be consistent everywhere and call
> isb()/dsb()/dmb() and NOT call ISB/DSB/DMB in some cases and the
> function names in others.

Reviewed-by: Stephen Warren <swarren at nvidia.com>
Tested-by: Stephen Warren <swarren at nvidia.com>