Commit Graph

7 Commits

Author SHA1 Message Date
Catalin Marinas ebf81a938d arm64: Fix DMA range invalidation for cache line unaligned buffers
If the buffer needing cache invalidation for inbound DMA does start or
end on a cache line aligned address, we need to use the non-destructive
clean&invalidate operation. This issue was introduced by commit
7363590d2c (arm64: Implement coherent DMA API based on swiotlb).

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Jon Medhurst (Tixy) <tixy@linaro.org>
2014-04-08 11:45:08 +01:00
Catalin Marinas c218bca74e arm64: Relax the kernel cache requirements for boot
With system caches for the host OS or architected caches for guest OS we
cannot easily guarantee that there are no dirty or stale cache lines for
the areas of memory written by the kernel during boot with the MMU off
(therefore non-cacheable accesses).

This patch adds the necessary cache maintenance during boot and relaxes
the booting requirements.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-04-05 10:06:18 +01:00
Mark Rutland bff705950e arm64: remove unnecessary cache flush at boot
Currently we flush the entire dcache at boot within __cpu_setup, but
this is unnecessary as the booting protocol demands that the dcache is
invalid and off upon entering the kernel. The presence of the cache
flush only serves to hide bugs in bootloaders, and is not safe in the
presence of SMP.

In an SMP boot scenario the CPUs enter coherency outside of the kernel,
and the primary CPU enables its caches before bringing up secondary
CPUs. Therefore if any secondary CPU has an entry in its cache (in
violation of the boot protocol), the primary CPU might snoop it even if
the secondary CPU's cache is disabled. The boot-time cache flush only
serves to hide a firmware bug, and slows down a cpu boot unnecessarily.

This patch removes the unnecessary boot-time cache flush.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
[catalin.marinas@arm.com: make __flush_dcache_all local only]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-03-04 01:07:22 +00:00
Catalin Marinas 7363590d2c arm64: Implement coherent DMA API based on swiotlb
This patch adds support for DMA API cache maintenance on SoCs without
hardware device cache coherency.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-02-27 17:16:59 +00:00
Jingoo Han 03324e6e6e arm64: mm: fix the function name in comment of __flush_dcache_area
Fix the function name of comment of __flush_dcache_area,
because __flush_dcache_area is the correct name. Also,
the missing variable 'size' is added to the comment.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-01-22 16:24:19 +00:00
Sukanto Ghosh b4fed07968 arm64: mm: Fix operands of clz in __flush_dcache_all
The format of the lower 32-bits of the 64-bit operand to 'dc cisw' is
unchanged from ARMv7 architecture and the upper bits are RES0. This
implies that the 'way' field of the operand of 'dc cisw' occupies the
bit-positions [31 .. (32-A)]. Due to the use of 64-bit extended operands
to 'clz', the existing implementation of __flush_dcache_all is incorrectly
placing the 'way' field in the bit-positions [63 .. (64-A)].

Signed-off-by: Sukanto Ghosh <sghosh@apm.com>
Tested-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: stable@vger.kernel.org
2013-05-14 15:44:50 +01:00
Catalin Marinas f1a0c4aa09 arm64: Cache maintenance routines
The patch adds functionality required for cache maintenance. The AArch64
architecture mandates non-aliasing VIPT or PIPT D-cache and VIPT (may
have aliases) or ASID-tagged VIVT I-cache. Cache maintenance operations
are automatically broadcast in hardware between CPUs.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-09-17 13:42:00 +01:00