sha256.h

 1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2/*
 3 * SHA-256 (RISC-V accelerated)
 4 *
 5 * Copyright (C) 2022 VRULL GmbH
 6 * Author: Heiko Stuebner <heiko.stuebner@vrull.eu>
 7 *
 8 * Copyright (C) 2023 SiFive, Inc.
 9 * Author: Jerry Shih <jerry.shih@sifive.com>
10 */
11
12#include <asm/simd.h>
13#include <asm/vector.h>
14
15static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_extensions);
16
17asmlinkage void
18sha256_transform_zvknha_or_zvknhb_zvkb(struct sha256_block_state *state,
19				       const u8 *data, size_t nblocks);
20
21static void sha256_blocks(struct sha256_block_state *state,
22			  const u8 *data, size_t nblocks)
23{
24	if (static_branch_likely(&have_extensions) && likely(may_use_simd())) {
25		kernel_vector_begin();
26		sha256_transform_zvknha_or_zvknhb_zvkb(state, data, nblocks);
27		kernel_vector_end();
28	} else {
29		sha256_blocks_generic(state, data, nblocks);
30	}
31}
32
33#define sha256_mod_init_arch sha256_mod_init_arch
34static void sha256_mod_init_arch(void)
35{
36	/* Both zvknha and zvknhb provide the SHA-256 instructions. */
37	if ((riscv_isa_extension_available(NULL, ZVKNHA) ||
38	     riscv_isa_extension_available(NULL, ZVKNHB)) &&
39	    riscv_isa_extension_available(NULL, ZVKB) &&
40	    riscv_vector_vlen() >= 128)
41		static_branch_enable(&have_extensions);
42}