powerpc 8xx: defconfig: slice by 4 is more efficient than the default slice by 8 on Powerpc 8xx.
On PPC_8xx, CRC32_SLICEBY4 is more efficient (almost twice) than CRC32_SLICEBY8,
as shown below:
With CRC32_SLICEBY8:
[ 1.109204] crc32: CRC_LE_BITS = 64, CRC_BE BITS = 64
[ 1.114401] crc32: self tests passed, processed 225944 bytes in 15118910 nsec
[ 1.130655] crc32c: CRC_LE_BITS = 64
[ 1.134235] crc32c: self tests passed, processed 225944 bytes in 4479879 nsec
With CRC32_SLICEBY4:
[ 1.097129] crc32: CRC_LE_BITS = 32, CRC_BE BITS = 32
[ 1.101878] crc32: self tests passed, processed 225944 bytes in 8616242 nsec
[ 1.116298] crc32c: CRC_LE_BITS = 32
[ 1.119607] crc32c: self tests passed, processed 225944 bytes in 3289576 nsec
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
diff --git a/arch/powerpc/configs/adder875_defconfig b/arch/powerpc/configs/adder875_defconfig
index 6912874..15b1ff5 100644
--- a/arch/powerpc/configs/adder875_defconfig
+++ b/arch/powerpc/configs/adder875_defconfig
@@ -70,3 +70,4 @@
CONFIG_DETECT_HUNG_TASK=y
CONFIG_DEBUG_INFO=y
# CONFIG_RCU_CPU_STALL_DETECTOR is not set
+CONFIG_CRC32_SLICEBY4=y