1 files changed, 75 insertions, 0 deletions
diff --git a/lib/crypto/riscv/chacha-riscv64-glue.c b/lib/crypto/riscv/chacha-riscv64-glue.c
new file mode 100644
index 000000000000..8c3f11d79be3
--- /dev/null
+++ b/lib/crypto/riscv/chacha-riscv64-glue.c
@@ -0,0 +1,75 @@
+// 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/chacha.h>
+#include <crypto/internal/simd.h>
+#include <linux/linkage.h>
+#include <linux/module.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);
+
+void hchacha_block_arch(const struct chacha_state *state,
+			u32 out[HCHACHA_OUT_WORDS], int nrounds)
+{
+	hchacha_block_generic(state, out, nrounds);
+}
+EXPORT_SYMBOL(hchacha_block_arch);
+
+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();
+}
+EXPORT_SYMBOL(chacha_crypt_arch);
+
+bool chacha_is_arch_optimized(void)
+{
+	return static_key_enabled(&use_zvkb);
+}
+EXPORT_SYMBOL(chacha_is_arch_optimized);
+
+static int __init riscv64_chacha_mod_init(void)
+{
+	if (riscv_isa_extension_available(NULL, ZVKB) &&
+	    riscv_vector_vlen() >= 128)
+		static_branch_enable(&use_zvkb);
+	return 0;
+}
+subsys_initcall(riscv64_chacha_mod_init);
+
+static void __exit riscv64_chacha_mod_exit(void)
+{
+}
+module_exit(riscv64_chacha_mod_exit);
+
+MODULE_DESCRIPTION("ChaCha stream cipher (RISC-V optimized)");
+MODULE_AUTHOR("Jerry Shih <jerry.shih@sifive.com>");
+MODULE_LICENSE("GPL");