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Diffstat (limited to 'arch/arm64/lib/crc32.S')
| -rw-r--r-- | arch/arm64/lib/crc32.S | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/arch/arm64/lib/crc32.S b/arch/arm64/lib/crc32.S new file mode 100644 index 000000000000..5bc1e85b4e1c --- /dev/null +++ b/arch/arm64/lib/crc32.S @@ -0,0 +1,60 @@ +/* + * Accelerated CRC32(C) using AArch64 CRC instructions + * + * Copyright (C) 2016 - 2018 Linaro Ltd <ard.biesheuvel@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/linkage.h> +#include <asm/alternative.h> +#include <asm/assembler.h> + + .cpu generic+crc + + .macro __crc32, c +0: subs x2, x2, #16 + b.mi 8f + ldp x3, x4, [x1], #16 +CPU_BE( rev x3, x3 ) +CPU_BE( rev x4, x4 ) + crc32\c\()x w0, w0, x3 + crc32\c\()x w0, w0, x4 + b.ne 0b + ret + +8: tbz x2, #3, 4f + ldr x3, [x1], #8 +CPU_BE( rev x3, x3 ) + crc32\c\()x w0, w0, x3 +4: tbz x2, #2, 2f + ldr w3, [x1], #4 +CPU_BE( rev w3, w3 ) + crc32\c\()w w0, w0, w3 +2: tbz x2, #1, 1f + ldrh w3, [x1], #2 +CPU_BE( rev16 w3, w3 ) + crc32\c\()h w0, w0, w3 +1: tbz x2, #0, 0f + ldrb w3, [x1] + crc32\c\()b w0, w0, w3 +0: ret + .endm + + .align 5 +ENTRY(crc32_le) +alternative_if_not ARM64_HAS_CRC32 + b crc32_le_base +alternative_else_nop_endif + __crc32 +ENDPROC(crc32_le) + + .align 5 +ENTRY(__crc32c_le) +alternative_if_not ARM64_HAS_CRC32 + b __crc32c_le_base +alternative_else_nop_endif + __crc32 c +ENDPROC(__crc32c_le) |