Commit Graph

2 Commits

Author SHA1 Message Date
Ard Biesheuvel 658fa754cd crypto: arm/aes - avoid reserved 'tt' mnemonic in asm code
The ARMv8-M architecture introduces 'tt' and 'ttt' instructions,
which means we can no longer use 'tt' as a register alias on recent
versions of binutils for ARM. So replace the alias with 'ttab'.

Fixes: 81edb42629 ("crypto: arm/aes - replace scalar AES cipher")
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-01-13 18:47:21 +08:00
Ard Biesheuvel 81edb42629 crypto: arm/aes - replace scalar AES cipher
This replaces the scalar AES cipher that originates in the OpenSSL project
with a new implementation that is ~15% (*) faster (on modern cores), and
reuses the lookup tables and the key schedule generation routines from the
generic C implementation (which is usually compiled in anyway due to
networking and other subsystems depending on it).

Note that the bit sliced NEON code for AES still depends on the scalar cipher
that this patch replaces, so it is not removed entirely yet.

* On Cortex-A57, the performance increases from 17.0 to 14.9 cycles per byte
  for 128-bit keys.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-01-13 00:26:50 +08:00