// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012 Intel Corporation
 * Copyright (C) 2017 Linaro Ltd. <ard.biesheuvel@linaro.org>
 */

#include <arm_neon.h>
#include "neon.h"

#ifdef CONFIG_ARM
/*
 * AArch32 does not provide this intrinsic natively because it does not
 * implement the underlying instruction. AArch32 only provides a 64-bit
 * wide vtbl.8 instruction, so use that instead.
 */
static uint8x16_t vqtbl1q_u8(uint8x16_t a, uint8x16_t b)
{
        union {
                uint8x16_t      val;
                uint8x8x2_t     pair;
        } __a = { a };

        return vcombine_u8(vtbl2_u8(__a.pair, vget_low_u8(b)),
                           vtbl2_u8(__a.pair, vget_high_u8(b)));
}
#endif

void __raid6_2data_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dp,
                              uint8_t *dq, const uint8_t *pbmul,
                              const uint8_t *qmul)
{
        uint8x16_t pm0 = vld1q_u8(pbmul);
        uint8x16_t pm1 = vld1q_u8(pbmul + 16);
        uint8x16_t qm0 = vld1q_u8(qmul);
        uint8x16_t qm1 = vld1q_u8(qmul + 16);
        uint8x16_t x0f = vdupq_n_u8(0x0f);

        /*
         * while ( bytes-- ) {
         *      uint8_t px, qx, db;
         *
         *      px    = *p ^ *dp;
         *      qx    = qmul[*q ^ *dq];
         *      *dq++ = db = pbmul[px] ^ qx;
         *      *dp++ = db ^ px;
         *      p++; q++;
         * }
         */

        while (bytes) {
                uint8x16_t vx, vy, px, qx, db;

                px = veorq_u8(vld1q_u8(p), vld1q_u8(dp));
                vx = veorq_u8(vld1q_u8(q), vld1q_u8(dq));

                vy = vshrq_n_u8(vx, 4);
                vx = vqtbl1q_u8(qm0, vandq_u8(vx, x0f));
                vy = vqtbl1q_u8(qm1, vy);
                qx = veorq_u8(vx, vy);

                vy = vshrq_n_u8(px, 4);
                vx = vqtbl1q_u8(pm0, vandq_u8(px, x0f));
                vy = vqtbl1q_u8(pm1, vy);
                vx = veorq_u8(vx, vy);
                db = veorq_u8(vx, qx);

                vst1q_u8(dq, db);
                vst1q_u8(dp, veorq_u8(db, px));

                bytes -= 16;
                p += 16;
                q += 16;
                dp += 16;
                dq += 16;
        }
}

void __raid6_datap_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dq,
                              const uint8_t *qmul)
{
        uint8x16_t qm0 = vld1q_u8(qmul);
        uint8x16_t qm1 = vld1q_u8(qmul + 16);
        uint8x16_t x0f = vdupq_n_u8(0x0f);

        /*
         * while (bytes--) {
         *      *p++ ^= *dq = qmul[*q ^ *dq];
         *      q++; dq++;
         * }
         */

        while (bytes) {
                uint8x16_t vx, vy;

                vx = veorq_u8(vld1q_u8(q), vld1q_u8(dq));

                vy = vshrq_n_u8(vx, 4);
                vx = vqtbl1q_u8(qm0, vandq_u8(vx, x0f));
                vy = vqtbl1q_u8(qm1, vy);
                vx = veorq_u8(vx, vy);
                vy = veorq_u8(vx, vld1q_u8(p));

                vst1q_u8(dq, vx);
                vst1q_u8(p, vy);

                bytes -= 16;
                p += 16;
                q += 16;
                dq += 16;
        }
}