sha256.h

 1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2/*
 3 * SHA-256 optimized using the CP Assist for Cryptographic Functions (CPACF)
 4 *
 5 * Copyright 2025 Google LLC
 6 */
 7#include <asm/cpacf.h>
 8#include <linux/cpufeature.h>
 9
10static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_cpacf_sha256);
11
12static void sha256_blocks(struct sha256_block_state *state,
13			  const u8 *data, size_t nblocks)
14{
15	if (static_branch_likely(&have_cpacf_sha256))
16		cpacf_kimd(CPACF_KIMD_SHA_256, state, data,
17			   nblocks * SHA256_BLOCK_SIZE);
18	else
19		sha256_blocks_generic(state, data, nblocks);
20}
21
22#define sha256_mod_init_arch sha256_mod_init_arch
23static void sha256_mod_init_arch(void)
24{
25	if (cpu_have_feature(S390_CPU_FEATURE_MSA) &&
26	    cpacf_query_func(CPACF_KIMD, CPACF_KIMD_SHA_256))
27		static_branch_enable(&have_cpacf_sha256);
28}