From 5f2f5eaa3e373c3a07a4f3552fe13d9cde5e23e5 Mon Sep 17 00:00:00 2001 From: Kevin Bracey Date: Tue, 18 Jan 2022 12:23:51 +0200 Subject: [PATCH] arm64: lib: accelerate crc32_be It makes no sense to leave crc32_be using the generic code while we only accelerate the little-endian ops. Even though the big-endian form doesn't fit as smoothly into the arm64, we can speed it up and avoid hitting the D cache. Tested on Cortex-A53. Without acceleration: crc32: CRC_LE_BITS = 64, CRC_BE BITS = 64 crc32: self tests passed, processed 225944 bytes in 192240 nsec crc32c: CRC_LE_BITS = 64 crc32c: self tests passed, processed 112972 bytes in 21360 nsec With acceleration: crc32: CRC_LE_BITS = 64, CRC_BE BITS = 64 crc32: self tests passed, processed 225944 bytes in 53480 nsec crc32c: CRC_LE_BITS = 64 crc32c: self tests passed, processed 112972 bytes in 21480 nsec Signed-off-by: Kevin Bracey Tested-by: Ard Biesheuvel Reviewed-by: Ard Biesheuvel Acked-by: Catalin Marinas Signed-off-by: Herbert Xu --- arch/arm64/lib/crc32.S | 87 ++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 73 insertions(+), 14 deletions(-) diff --git a/arch/arm64/lib/crc32.S b/arch/arm64/lib/crc32.S index 0f9e10e..8340dcc 100644 --- a/arch/arm64/lib/crc32.S +++ b/arch/arm64/lib/crc32.S @@ -11,7 +11,44 @@ .arch armv8-a+crc - .macro __crc32, c + .macro byteorder, reg, be + .if \be +CPU_LE( rev \reg, \reg ) + .else +CPU_BE( rev \reg, \reg ) + .endif + .endm + + .macro byteorder16, reg, be + .if \be +CPU_LE( rev16 \reg, \reg ) + .else +CPU_BE( rev16 \reg, \reg ) + .endif + .endm + + .macro bitorder, reg, be + .if \be + rbit \reg, \reg + .endif + .endm + + .macro bitorder16, reg, be + .if \be + rbit \reg, \reg + lsr \reg, \reg, #16 + .endif + .endm + + .macro bitorder8, reg, be + .if \be + rbit \reg, \reg + lsr \reg, \reg, #24 + .endif + .endm + + .macro __crc32, c, be=0 + bitorder w0, \be cmp x2, #16 b.lt 8f // less than 16 bytes @@ -24,10 +61,14 @@ add x8, x8, x1 add x1, x1, x7 ldp x5, x6, [x8] -CPU_BE( rev x3, x3 ) -CPU_BE( rev x4, x4 ) -CPU_BE( rev x5, x5 ) -CPU_BE( rev x6, x6 ) + byteorder x3, \be + byteorder x4, \be + byteorder x5, \be + byteorder x6, \be + bitorder x3, \be + bitorder x4, \be + bitorder x5, \be + bitorder x6, \be tst x7, #8 crc32\c\()x w8, w0, x3 @@ -55,33 +96,43 @@ CPU_BE( rev x6, x6 ) 32: ldp x3, x4, [x1], #32 sub x2, x2, #32 ldp x5, x6, [x1, #-16] -CPU_BE( rev x3, x3 ) -CPU_BE( rev x4, x4 ) -CPU_BE( rev x5, x5 ) -CPU_BE( rev x6, x6 ) + byteorder x3, \be + byteorder x4, \be + byteorder x5, \be + byteorder x6, \be + bitorder x3, \be + bitorder x4, \be + bitorder x5, \be + bitorder x6, \be crc32\c\()x w0, w0, x3 crc32\c\()x w0, w0, x4 crc32\c\()x w0, w0, x5 crc32\c\()x w0, w0, x6 cbnz x2, 32b -0: ret +0: bitorder w0, \be + ret 8: tbz x2, #3, 4f ldr x3, [x1], #8 -CPU_BE( rev x3, x3 ) + byteorder x3, \be + bitorder x3, \be crc32\c\()x w0, w0, x3 4: tbz x2, #2, 2f ldr w3, [x1], #4 -CPU_BE( rev w3, w3 ) + byteorder w3, \be + bitorder w3, \be crc32\c\()w w0, w0, w3 2: tbz x2, #1, 1f ldrh w3, [x1], #2 -CPU_BE( rev16 w3, w3 ) + byteorder16 w3, \be + bitorder16 w3, \be crc32\c\()h w0, w0, w3 1: tbz x2, #0, 0f ldrb w3, [x1] + bitorder8 w3, \be crc32\c\()b w0, w0, w3 -0: ret +0: bitorder w0, \be + ret .endm .align 5 @@ -99,3 +150,11 @@ alternative_if_not ARM64_HAS_CRC32 alternative_else_nop_endif __crc32 c SYM_FUNC_END(__crc32c_le) + + .align 5 +SYM_FUNC_START(crc32_be) +alternative_if_not ARM64_HAS_CRC32 + b crc32_be_base +alternative_else_nop_endif + __crc32 be=1 +SYM_FUNC_END(crc32_be) -- 2.7.4