diff options
Diffstat (limited to 'lib/crypto/riscv/chacha.h')
| -rw-r--r-- | lib/crypto/riscv/chacha.h | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/lib/crypto/riscv/chacha.h b/lib/crypto/riscv/chacha.h new file mode 100644 index 000000000000..5c000c6aef4b --- /dev/null +++ b/lib/crypto/riscv/chacha.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * ChaCha stream cipher (RISC-V optimized) + * + * Copyright (C) 2023 SiFive, Inc. + * Author: Jerry Shih <jerry.shih@sifive.com> + */ + +#include <asm/simd.h> +#include <asm/vector.h> +#include <crypto/internal/simd.h> +#include <linux/linkage.h> + +static __ro_after_init DEFINE_STATIC_KEY_FALSE(use_zvkb); + +asmlinkage void chacha_zvkb(struct chacha_state *state, const u8 *in, u8 *out, + size_t nblocks, int nrounds); + +#define hchacha_block_arch hchacha_block_generic /* not implemented yet */ + +static void chacha_crypt_arch(struct chacha_state *state, u8 *dst, + const u8 *src, unsigned int bytes, int nrounds) +{ + u8 block_buffer[CHACHA_BLOCK_SIZE]; + unsigned int full_blocks = bytes / CHACHA_BLOCK_SIZE; + unsigned int tail_bytes = bytes % CHACHA_BLOCK_SIZE; + + if (!static_branch_likely(&use_zvkb) || !crypto_simd_usable()) + return chacha_crypt_generic(state, dst, src, bytes, nrounds); + + kernel_vector_begin(); + if (full_blocks) { + chacha_zvkb(state, src, dst, full_blocks, nrounds); + src += full_blocks * CHACHA_BLOCK_SIZE; + dst += full_blocks * CHACHA_BLOCK_SIZE; + } + if (tail_bytes) { + memcpy(block_buffer, src, tail_bytes); + chacha_zvkb(state, block_buffer, block_buffer, 1, nrounds); + memcpy(dst, block_buffer, tail_bytes); + } + kernel_vector_end(); +} + +#define chacha_mod_init_arch chacha_mod_init_arch +static void chacha_mod_init_arch(void) +{ + if (riscv_isa_extension_available(NULL, ZVKB) && + riscv_vector_vlen() >= 128) + static_branch_enable(&use_zvkb); +} |