[PATCH v5 0/3] arm64: Add optimized memset/memcpy/memove functions

[Stefan Roese]

On an NXP LX2160 based platform it has been noticed, that the currently
implemented memset/memcpy functions for aarch64 are suboptimal.
Especially the memset() for clearing the NXP MC firmware memory is very
expensive (time-wise).

This patchset now adds the optimized functions ported from this
repository:
https://github.com/ARM-software/optimized-routines

As the optimized memset function make use of the dc opcode, which needs
the caches to be enabled, an additional check is added and a simple
memset version is used in this case.

Please note that checkpatch.pl complains about some issue with this
imported file: arch/arm/lib/asmdefs.h
Since it's imported I did explicitly not make any changes here, to make
potential future sync'ing easer.

Here some numbers to see the speed improments:
Current original version:
-------------------------
memset() 32 Bytes, 16M times:
time: 0.446 seconds

memset() 16MiB, 256 times:
time: 1.076 seconds

memcpy() 512MiB:
time: 0.224 seconds

New optimized version:
----------------------
memset() 32 Bytes, 16M times:
time: 0.287 seconds

memset() 16MiB, 256 times:
time: 0.292 seconds

memcpy() 512MiB:
time: 0.222 seconds

Summary:
The optimized memcpy is nearly identical to the original one. But the
optimized memset is much faster, for small and big sizes. Small sizes
factor ~1.6 and big sizes factor ~3.7.

Note: These measurements were done on the NXP LX2160ARDB board.

Thanks,
Stefan

Changes in v5:
- memmove is now auto-selected (or deselected) with the memcpy
  Kconfig selection as it's entry is the same as memcpy for ARM64

Changes in v4:
- Use macros instead of register names, following the optimized code
- Add zero size check

Changes in v3:
- Add memmove alias, as this function also handles it optimized
- Add memmove as well

Changes in v2:
- Add file names and locations and git commit ID from imported files
  to the commit message
- New patch

Stefan Roese (3):
  arm64: arch/arm/lib: Add optimized memset/memcpy/memmove functions
  arm64: memset-arm64: Use simple memset when cache is disabled
  arm64: Kconfig: Enable usage of optimized memset/memcpy/memmove

 arch/arm/Kconfig              |  37 +++++-
 arch/arm/include/asm/string.h |   4 +
 arch/arm/lib/Makefile         |   5 +
 arch/arm/lib/asmdefs.h        |  98 ++++++++++++++
 arch/arm/lib/memcpy-arm64.S   | 242 ++++++++++++++++++++++++++++++++++
 arch/arm/lib/memset-arm64.S   | 148 +++++++++++++++++++++
 6 files changed, 528 insertions(+), 6 deletions(-)
 create mode 100644 arch/arm/lib/asmdefs.h
 create mode 100644 arch/arm/lib/memcpy-arm64.S
 create mode 100644 arch/arm/lib/memset-arm64.S

-- 
2.33.0