When the CPU has support for the byte and word exclusive operations,
userspace should use them in preference to the SWP instructions.
Detect the presence of these instructions by reading the ISAR CPU ID
registers and adjust the ELF HWCAP mask appropriately.

Note that ARM1136 < r1p0 has no ISAR4, so this is explicitly detected
and the test disabled, leaving the current situation where HWCAP_SWP
is set.

Tested-by: Tony Lindgren <tony@atomide.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Fix a long standing bug where, for ARMv6+, we don't fully ensure that
the C code sets the same cache policy as the assembly code.  This was
introduced partially by commit 11179d8ca28d ([ARM] 4497/1: Only allow
safe cache configurations on ARMv6 and later) and also by adding SMP
support.

This patch sets the default cache policy based on the flags used by the
assembly code, and then ensures that when a cache policy command line
argument is used, we verify that on ARMv6, it matches the initial setup.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

memblock is now fully integrated into the kernel and is the prefered
method for tracking memory. Rather than reinvent the wheel with
meminfo, migrate to using memblock directly instead of meminfo as
an intermediate.

Acked-by: Jason Cooper <jason@lakedaemon.net>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Rather than reading the cr_alignment variable, use get_cr() to read
directly from the hardware instead.  We have two places where this
occurs, neither of them are performance critical.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This allocates feature bits 0-4 in HWCAP2 for the crypto and CRC
extensions introduced in ARMv8.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This enables AT_HWCAP2 for ARM. The generic support for this
new ELF auxv entry was added in commit 2171364d1a9 (powerpc:
Add HWCAP2 aux entry)

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Commit ad6492b8 added much needed memblock_virt_alloc_low() and further
commit 07bacb3 {memblock, bootmem: restore goal for alloc_low} fixed
the issue with low memory limit thanks to Yinghai. But even after all
these fixes, there is still one case where the limit check done with
ARCH_LOW_ADDRESS_LIMIT for low memory fails. Russell pointed out the
issue with 32 bit LPAE machines in below thread.
	https://lkml.org/lkml/2014/1/28/364

Since on some LPAE machines where memory start address is beyond 4GB,
the low memory marker in memblock will be set to default
ARCH_LOW_ADDRESS_LIMIT which is wrong. We can fix this by letting
architectures set the ARCH_LOW_ADDRESS_LIMIT using another export
similar to memblock_set_current_limit() but am not sure whether
its worth the trouble. Tell me if you think otherwise.

Rather am just trying to fix that one broken case using
memblock_virt_alloc() in setup code since the memblock.current_limit
is updated appropriately makes it work on all ARM 32 bit machines.

Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Strashko, Grygorii <grygorii.strashko@ti.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The new memblock_virt APIs are used to replaced old bootmem API.

We need to allocate page below 4G for swiotlb.

That should fix regression on Andrew's system that is using swiotlb.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>