1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * SHA-256 optimized for ARM64 4 * 5 * Copyright 2025 Google LLC 6 */ 7 #include <asm/neon.h> 8 #include <crypto/internal/simd.h> 9 #include <linux/cpufeature.h> 10 11 asmlinkage void sha256_block_data_order(struct sha256_block_state *state, 12 const u8 *data, size_t nblocks); 13 asmlinkage void sha256_block_neon(struct sha256_block_state *state, 14 const u8 *data, size_t nblocks); 15 asmlinkage size_t __sha256_ce_transform(struct sha256_block_state *state, 16 const u8 *data, size_t nblocks); 17 18 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_neon); 19 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_ce); 20 21 static void sha256_blocks(struct sha256_block_state *state, 22 const u8 *data, size_t nblocks) 23 { 24 if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && 25 static_branch_likely(&have_neon) && crypto_simd_usable()) { 26 if (static_branch_likely(&have_ce)) { 27 do { 28 size_t rem; 29 30 kernel_neon_begin(); 31 rem = __sha256_ce_transform(state, 32 data, nblocks); 33 kernel_neon_end(); 34 data += (nblocks - rem) * SHA256_BLOCK_SIZE; 35 nblocks = rem; 36 } while (nblocks); 37 } else { 38 kernel_neon_begin(); 39 sha256_block_neon(state, data, nblocks); 40 kernel_neon_end(); 41 } 42 } else { 43 sha256_block_data_order(state, data, nblocks); 44 } 45 } 46 47 #ifdef CONFIG_KERNEL_MODE_NEON 48 #define sha256_mod_init_arch sha256_mod_init_arch 49 static inline void sha256_mod_init_arch(void) 50 { 51 if (cpu_have_named_feature(ASIMD)) { 52 static_branch_enable(&have_neon); 53 if (cpu_have_named_feature(SHA2)) 54 static_branch_enable(&have_ce); 55 } 56 } 57 #endif /* CONFIG_KERNEL_MODE_NEON */ 58