crypto: aesni-intel - Ported implementation to x86-32

The AES-NI instructions are also available in legacy mode so the 32-bit
architecture may profit from those, too.

To illustrate the performance gain here's a short summary of a dm-crypt
speed test on a Core i7 M620 running at 2.67GHz comparing both assembler
implementations:

x86:                   i568       aes-ni    delta
ECB, 256 bit:     93.8 MB/s   123.3 MB/s   +31.4%
CBC, 256 bit:     84.8 MB/s   262.3 MB/s  +209.3%
LRW, 256 bit:    108.6 MB/s   222.1 MB/s  +104.5%
XTS, 256 bit:    105.0 MB/s   205.5 MB/s   +95.7%

Additionally, due to some minor optimizations, the 64-bit version also
got a minor performance gain as seen below:

x86-64:           old impl.    new impl.    delta
ECB, 256 bit:    121.1 MB/s   123.0 MB/s    +1.5%
CBC, 256 bit:    285.3 MB/s   290.8 MB/s    +1.9%
LRW, 256 bit:    263.7 MB/s   265.3 MB/s    +0.6%
XTS, 256 bit:    251.1 MB/s   255.3 MB/s    +1.7%

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 7 insertions, 5 deletions

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 69437e21217f..467491df3e3a 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -539,8 +539,9 @@ config CRYPTO_AES_X86_64
 
 config CRYPTO_AES_NI_INTEL
         tristate "AES cipher algorithms (AES-NI)"
-        depends on (X86 || UML_X86) && 64BIT
-        select CRYPTO_AES_X86_64
+        depends on (X86 || UML_X86)
+        select CRYPTO_AES_X86_64 if 64BIT
+        select CRYPTO_AES_586 if !64BIT
         select CRYPTO_CRYPTD
         select CRYPTO_ALGAPI
         select CRYPTO_FPU
@@ -563,9 +564,10 @@ config CRYPTO_AES_NI_INTEL
 
           See <http://csrc.nist.gov/encryption/aes/> for more information.
 
-          In addition to AES cipher algorithm support, the
-          acceleration for some popular block cipher mode is supported
-          too, including ECB, CBC, CTR, LRW, PCBC, XTS.
+          In addition to AES cipher algorithm support, the acceleration
+          for some popular block cipher mode is supported too, including
+          ECB, CBC, LRW, PCBC, XTS. The 64 bit version has additional
+          acceleration for CTR.
 
 config CRYPTO_ANUBIS
         tristate "Anubis cipher algorithm"