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| author | Eric Biggers <ebiggers@google.com> | 2024-02-07 22:08:51 -0800 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-03-20 08:56:10 -0700 |
| commit | da215b089b5d4ff30745c59922b54b309d55a5d8 (patch) | |
| tree | 5246af0a3d1b9c1d96ff8becbb7d289c52da75fb | |
| parent | 028d1aee1f0768f96a40871e2e33727a10ff146f (diff) | |
| download | linux-da215b089b5d4ff30745c59922b54b309d55a5d8.tar.gz | |
crypto: riscv - parallelize AES-CBC decryption
Since CBC decryption is parallelizable, make the RISC-V implementation
of AES-CBC decryption process multiple blocks at a time, instead of
processing the blocks one by one. This should improve performance.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20240208060851.154129-1-ebiggers@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| -rw-r--r-- | arch/riscv/crypto/aes-riscv64-zvkned.S | 24 |
1 files changed, 15 insertions, 9 deletions
diff --git a/arch/riscv/crypto/aes-riscv64-zvkned.S b/arch/riscv/crypto/aes-riscv64-zvkned.S index 78d4e1186c074..43541aad6386c 100644 --- a/arch/riscv/crypto/aes-riscv64-zvkned.S +++ b/arch/riscv/crypto/aes-riscv64-zvkned.S @@ -139,19 +139,25 @@ SYM_FUNC_END(aes_ecb_decrypt_zvkned) .endm .macro aes_cbc_decrypt keylen + srli LEN, LEN, 2 // Convert LEN from bytes to words vle32.v v16, (IVP) // Load IV 1: - vle32.v v17, (INP) // Load ciphertext block - vmv.v.v v18, v17 // Save ciphertext block - aes_decrypt v17, \keylen // Decrypt - vxor.vv v17, v17, v16 // XOR with IV or prev ciphertext block - vse32.v v17, (OUTP) // Store plaintext block - vmv.v.v v16, v18 // Next "IV" is prev ciphertext block - addi INP, INP, 16 - addi OUTP, OUTP, 16 - addi LEN, LEN, -16 + vsetvli t0, LEN, e32, m4, ta, ma + vle32.v v20, (INP) // Load ciphertext blocks + vslideup.vi v16, v20, 4 // Setup prev ciphertext blocks + addi t1, t0, -4 + vslidedown.vx v24, v20, t1 // Save last ciphertext block + aes_decrypt v20, \keylen // Decrypt the blocks + vxor.vv v20, v20, v16 // XOR with prev ciphertext blocks + vse32.v v20, (OUTP) // Store plaintext blocks + vmv.v.v v16, v24 // Next "IV" is last ciphertext block + slli t1, t0, 2 // Words to bytes + add INP, INP, t1 + add OUTP, OUTP, t1 + sub LEN, LEN, t0 bnez LEN, 1b + vsetivli zero, 4, e32, m1, ta, ma vse32.v v16, (IVP) // Store next IV ret .endm |