/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (C) 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 <asm/simd.h>
#include <linux/cpufeature.h>

static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_sha3);

asmlinkage size_t sha3_ce_transform(struct sha3_state *state, const u8 *data,
                                    size_t nblocks, size_t block_size);

static void sha3_absorb_blocks(struct sha3_state *state, const u8 *data,
                               size_t nblocks, size_t block_size)
{
        if (static_branch_likely(&have_sha3) && likely(may_use_simd())) {
                do {
                        size_t rem;

                        scoped_ksimd()
                                rem = sha3_ce_transform(state, data, nblocks,
                                                        block_size);
                        data += (nblocks - rem) * block_size;
                        nblocks = rem;
                } while (nblocks);
        } else {
                sha3_absorb_blocks_generic(state, data, nblocks, block_size);
        }
}

static void sha3_keccakf(struct sha3_state *state)
{
        if (static_branch_likely(&have_sha3) && likely(may_use_simd())) {
                /*
                 * Passing zeroes into sha3_ce_transform() gives the plain
                 * Keccak-f permutation, which is what we want here.  Any
                 * supported block size may be used.  Use SHA3_512_BLOCK_SIZE
                 * since it's the shortest.
                 */
                static const u8 zeroes[SHA3_512_BLOCK_SIZE];

                scoped_ksimd()
                        sha3_ce_transform(state, zeroes, 1, sizeof(zeroes));
        } else {
                sha3_keccakf_generic(state);
        }
}

#define sha3_mod_init_arch sha3_mod_init_arch
static void sha3_mod_init_arch(void)
{
        if (cpu_have_named_feature(SHA3))
                static_branch_enable(&have_sha3);
}