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Diffstat (limited to 'lib/raid6/neon.uc')
| -rw-r--r-- | lib/raid6/neon.uc | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/lib/raid6/neon.uc b/lib/raid6/neon.uc new file mode 100644 index 000000000..b7c68030d --- /dev/null +++ b/lib/raid6/neon.uc @@ -0,0 +1,152 @@ +/* ----------------------------------------------------------------------- + * + * neon.uc - RAID-6 syndrome calculation using ARM NEON instructions + * + * Copyright (C) 2012 Rob Herring + * Copyright (C) 2015 Linaro Ltd. <ard.biesheuvel@linaro.org> + * + * Based on altivec.uc: + * Copyright 2002-2004 H. Peter Anvin - All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, Inc., 53 Temple Place Ste 330, + * Boston MA 02111-1307, USA; either version 2 of the License, or + * (at your option) any later version; incorporated herein by reference. + * + * ----------------------------------------------------------------------- */ + +/* + * neon$#.c + * + * $#-way unrolled NEON intrinsics math RAID-6 instruction set + * + * This file is postprocessed using unroll.awk + */ + +#include <arm_neon.h> + +typedef uint8x16_t unative_t; + +#define NSIZE sizeof(unative_t) + +/* + * The SHLBYTE() operation shifts each byte left by 1, *not* + * rolling over into the next byte + */ +static inline unative_t SHLBYTE(unative_t v) +{ + return vshlq_n_u8(v, 1); +} + +/* + * The MASK() operation returns 0xFF in any byte for which the high + * bit is 1, 0x00 for any byte for which the high bit is 0. + */ +static inline unative_t MASK(unative_t v) +{ + return (unative_t)vshrq_n_s8((int8x16_t)v, 7); +} + +static inline unative_t PMUL(unative_t v, unative_t u) +{ + return (unative_t)vmulq_p8((poly8x16_t)v, (poly8x16_t)u); +} + +void raid6_neon$#_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs) +{ + uint8_t **dptr = (uint8_t **)ptrs; + uint8_t *p, *q; + int d, z, z0; + + register unative_t wd$$, wq$$, wp$$, w1$$, w2$$; + const unative_t x1d = vdupq_n_u8(0x1d); + + z0 = disks - 3; /* Highest data disk */ + p = dptr[z0+1]; /* XOR parity */ + q = dptr[z0+2]; /* RS syndrome */ + + for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { + wq$$ = wp$$ = vld1q_u8(&dptr[z0][d+$$*NSIZE]); + for ( z = z0-1 ; z >= 0 ; z-- ) { + wd$$ = vld1q_u8(&dptr[z][d+$$*NSIZE]); + wp$$ = veorq_u8(wp$$, wd$$); + w2$$ = MASK(wq$$); + w1$$ = SHLBYTE(wq$$); + + w2$$ = vandq_u8(w2$$, x1d); + w1$$ = veorq_u8(w1$$, w2$$); + wq$$ = veorq_u8(w1$$, wd$$); + } + vst1q_u8(&p[d+NSIZE*$$], wp$$); + vst1q_u8(&q[d+NSIZE*$$], wq$$); + } +} + +void raid6_neon$#_xor_syndrome_real(int disks, int start, int stop, + unsigned long bytes, void **ptrs) +{ + uint8_t **dptr = (uint8_t **)ptrs; + uint8_t *p, *q; + int d, z, z0; + + register unative_t wd$$, wq$$, wp$$, w1$$, w2$$; + const unative_t x1d = vdupq_n_u8(0x1d); + + z0 = stop; /* P/Q right side optimization */ + p = dptr[disks-2]; /* XOR parity */ + q = dptr[disks-1]; /* RS syndrome */ + + for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { + wq$$ = vld1q_u8(&dptr[z0][d+$$*NSIZE]); + wp$$ = veorq_u8(vld1q_u8(&p[d+$$*NSIZE]), wq$$); + + /* P/Q data pages */ + for ( z = z0-1 ; z >= start ; z-- ) { + wd$$ = vld1q_u8(&dptr[z][d+$$*NSIZE]); + wp$$ = veorq_u8(wp$$, wd$$); + w2$$ = MASK(wq$$); + w1$$ = SHLBYTE(wq$$); + + w2$$ = vandq_u8(w2$$, x1d); + w1$$ = veorq_u8(w1$$, w2$$); + wq$$ = veorq_u8(w1$$, wd$$); + } + /* P/Q left side optimization */ + for ( z = start-1 ; z >= 3 ; z -= 4 ) { + w2$$ = vshrq_n_u8(wq$$, 4); + w1$$ = vshlq_n_u8(wq$$, 4); + + w2$$ = PMUL(w2$$, x1d); + wq$$ = veorq_u8(w1$$, w2$$); + } + + switch (z) { + case 2: + w2$$ = vshrq_n_u8(wq$$, 5); + w1$$ = vshlq_n_u8(wq$$, 3); + + w2$$ = PMUL(w2$$, x1d); + wq$$ = veorq_u8(w1$$, w2$$); + break; + case 1: + w2$$ = vshrq_n_u8(wq$$, 6); + w1$$ = vshlq_n_u8(wq$$, 2); + + w2$$ = PMUL(w2$$, x1d); + wq$$ = veorq_u8(w1$$, w2$$); + break; + case 0: + w2$$ = MASK(wq$$); + w1$$ = SHLBYTE(wq$$); + + w2$$ = vandq_u8(w2$$, x1d); + wq$$ = veorq_u8(w1$$, w2$$); + } + w1$$ = vld1q_u8(&q[d+NSIZE*$$]); + wq$$ = veorq_u8(wq$$, w1$$); + + vst1q_u8(&p[d+NSIZE*$$], wp$$); + vst1q_u8(&q[d+NSIZE*$$], wq$$); + } +} |