crypto: crc32c - Use Intel CRC32 instruction

From NHM processor onward, Intel processors can support hardware accelerated
CRC32c algorithm with the new CRC32 instruction in SSE 4.2 instruction set.
The patch detects the availability of the feature, and chooses the most proper
way to calculate CRC32c checksum.
Byte code instructions are used for compiler compatibility.
No MMX / XMM registers is involved in the implementation.

Signed-off-by: Austin Zhang <austin.zhang@intel.com>
Signed-off-by: Kent Liu <kent.liu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 12 insertions, 0 deletions

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 4f72b30..797b9e1 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -221,6 +221,18 @@ config CRYPTO_CRC32C
 	  See Castagnoli93.  This implementation uses lib/libcrc32c.
 	  Module will be crc32c.
 
+config CRYPTO_CRC32C_INTEL
+	tristate "CRC32c INTEL hardware acceleration"
+	depends on X86
+	select CRYPTO_HASH
+	help
+	  In Intel processor with SSE4.2 supported, the processor will
+	  support CRC32C implementation using hardware accelerated CRC32
+	  instruction. This option will create 'crc32c-intel' module,
+	  which will enable any routine to use the CRC32 instruction to
+	  gain performance compared with software implementation.
+	  Module will be crc32c-intel.
+
 config CRYPTO_MD4
 	tristate "MD4 digest algorithm"
 	select CRYPTO_ALGAPI