blob: 2f78c10b188152f80409869a5062c63a751b9442 [file] [log] [blame]
* Accelerated GHASH implementation with NEON/ARMv8 vmull.p8/64 instructions.
* Copyright (C) 2015 - 2017 Linaro Ltd. <>
* 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/assembler.h>
SHASH .req q0
T1 .req q1
XL .req q2
XM .req q3
XH .req q4
IN1 .req q4
SHASH_L .req d0
SHASH_H .req d1
T1_L .req d2
T1_H .req d3
XL_L .req d4
XL_H .req d5
XM_L .req d6
XM_H .req d7
XH_L .req d8
t0l .req d10
t0h .req d11
t1l .req d12
t1h .req d13
t2l .req d14
t2h .req d15
t3l .req d16
t3h .req d17
t4l .req d18
t4h .req d19
t0q .req q5
t1q .req q6
t2q .req q7
t3q .req q8
t4q .req q9
T2 .req q9
s1l .req d20
s1h .req d21
s2l .req d22
s2h .req d23
s3l .req d24
s3h .req d25
s4l .req d26
s4h .req d27
MASK .req d28
SHASH2_p8 .req d28
k16 .req d29
k32 .req d30
k48 .req d31
SHASH2_p64 .req d31
.fpu crypto-neon-fp-armv8
.macro __pmull_p64, rd, rn, rm, b1, b2, b3, b4
vmull.p64 \rd, \rn, \rm
* This implementation of 64x64 -> 128 bit polynomial multiplication
* using vmull.p8 instructions (8x8 -> 16) is taken from the paper
* "Fast Software Polynomial Multiplication on ARM Processors Using
* the NEON Engine" by Danilo Camara, Conrado Gouvea, Julio Lopez and
* Ricardo Dahab (
* It has been slightly tweaked for in-order performance, and to allow
* 'rq' to overlap with 'ad' or 'bd'.
.macro __pmull_p8, rq, ad, bd, b1=t4l, b2=t3l, b3=t4l, b4=t3l
vext.8 t0l, \ad, \ad, #1 @ A1
.ifc \b1, t4l
vext.8 t4l, \bd, \bd, #1 @ B1
vmull.p8 t0q, t0l, \bd @ F = A1*B
vext.8 t1l, \ad, \ad, #2 @ A2
vmull.p8 t4q, \ad, \b1 @ E = A*B1
.ifc \b2, t3l
vext.8 t3l, \bd, \bd, #2 @ B2
vmull.p8 t1q, t1l, \bd @ H = A2*B
vext.8 t2l, \ad, \ad, #3 @ A3
vmull.p8 t3q, \ad, \b2 @ G = A*B2
veor t0q, t0q, t4q @ L = E + F
.ifc \b3, t4l
vext.8 t4l, \bd, \bd, #3 @ B3
vmull.p8 t2q, t2l, \bd @ J = A3*B
veor t0l, t0l, t0h @ t0 = (L) (P0 + P1) << 8
veor t1q, t1q, t3q @ M = G + H
.ifc \b4, t3l
vext.8 t3l, \bd, \bd, #4 @ B4
vmull.p8 t4q, \ad, \b3 @ I = A*B3
veor t1l, t1l, t1h @ t1 = (M) (P2 + P3) << 16
vmull.p8 t3q, \ad, \b4 @ K = A*B4
vand t0h, t0h, k48
vand t1h, t1h, k32
veor t2q, t2q, t4q @ N = I + J
veor t0l, t0l, t0h
veor t1l, t1l, t1h
veor t2l, t2l, t2h @ t2 = (N) (P4 + P5) << 24
vand t2h, t2h, k16
veor t3l, t3l, t3h @ t3 = (K) (P6 + P7) << 32
vmov.i64 t3h, #0
vext.8 t0q, t0q, t0q, #15
veor t2l, t2l, t2h
vext.8 t1q, t1q, t1q, #14
vmull.p8 \rq, \ad, \bd @ D = A*B
vext.8 t2q, t2q, t2q, #13
vext.8 t3q, t3q, t3q, #12
veor t0q, t0q, t1q
veor t2q, t2q, t3q
veor \rq, \rq, t0q
veor \rq, \rq, t2q
// PMULL (64x64->128) based reduction for CPUs that can do
// it in a single instruction.
.macro __pmull_reduce_p64
vmull.p64 T1, XL_L, MASK
veor XH_L, XH_L, XM_H
vext.8 T1, T1, T1, #8
veor XL_H, XL_H, XM_L
veor T1, T1, XL
vmull.p64 XL, T1_H, MASK
// Alternative reduction for CPUs that lack support for the
// 64x64->128 PMULL instruction
.macro __pmull_reduce_p8
veor XL_H, XL_H, XM_L
veor XH_L, XH_L, XM_H
vshl.i64 T1, XL, #57
vshl.i64 T2, XL, #62
veor T1, T1, T2
vshl.i64 T2, XL, #63
veor T1, T1, T2
veor XL_H, XL_H, T1_L
veor XH_L, XH_L, T1_H
vshr.u64 T1, XL, #1
veor XH, XH, XL
veor XL, XL, T1
vshr.u64 T1, T1, #6
vshr.u64 XL, XL, #1
.macro ghash_update, pn
vld1.64 {XL}, [r1]
/* do the head block first, if supplied */
ldr ip, [sp]
teq ip, #0
beq 0f
vld1.64 {T1}, [ip]
teq r0, #0
b 1f
0: vld1.64 {T1}, [r2]!
subs r0, r0, #1
1: /* multiply XL by SHASH in GF(2^128) */
vrev64.8 T1, T1
vext.8 IN1, T1, T1, #8
veor T1_L, T1_L, XL_H
veor XL, XL, IN1
__pmull_\pn XH, XL_H, SHASH_H, s1h, s2h, s3h, s4h @ a1 * b1
veor T1, T1, XL
__pmull_\pn XL, XL_L, SHASH_L, s1l, s2l, s3l, s4l @ a0 * b0
__pmull_\pn XM, T1_L, SHASH2_\pn @ (a1+a0)(b1+b0)
veor T1, XL, XH
veor XM, XM, T1
veor T1, T1, XH
veor XL, XL, T1
bne 0b
vst1.64 {XL}, [r1]
bx lr
* void pmull_ghash_update(int blocks, u64 dg[], const char *src,
* struct ghash_key const *k, const char *head)
vld1.64 {SHASH}, [r3]
vmov.i8 MASK, #0xe1
vshl.u64 MASK, MASK, #57
ghash_update p64
vld1.64 {SHASH}, [r3]
vext.8 s1l, SHASH_L, SHASH_L, #1
vext.8 s2l, SHASH_L, SHASH_L, #2
vext.8 s3l, SHASH_L, SHASH_L, #3
vext.8 s4l, SHASH_L, SHASH_L, #4
vext.8 s1h, SHASH_H, SHASH_H, #1
vext.8 s2h, SHASH_H, SHASH_H, #2
vext.8 s3h, SHASH_H, SHASH_H, #3
vext.8 s4h, SHASH_H, SHASH_H, #4
vmov.i64 k16, #0xffff
vmov.i64 k32, #0xffffffff
vmov.i64 k48, #0xffffffffffff
ghash_update p8