1 files changed, 67 insertions, 0 deletions
diff --git a/arch/riscv/lib/crypto/sha256.c b/arch/riscv/lib/crypto/sha256.c
new file mode 100644
index 000000000000..71808397dff4
--- /dev/null
+++ b/arch/riscv/lib/crypto/sha256.c
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * SHA-256 (RISC-V accelerated)
+ *
+ * Copyright (C) 2022 VRULL GmbH
+ * Author: Heiko Stuebner <heiko.stuebner@vrull.eu>
+ *
+ * Copyright (C) 2023 SiFive, Inc.
+ * Author: Jerry Shih <jerry.shih@sifive.com>
+ */
+
+#include <asm/vector.h>
+#include <crypto/internal/sha2.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+asmlinkage void sha256_transform_zvknha_or_zvknhb_zvkb(
+	u32 state[SHA256_STATE_WORDS], const u8 *data, size_t nblocks);
+
+static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_extensions);
+
+void sha256_blocks_simd(u32 state[SHA256_STATE_WORDS],
+			const u8 *data, size_t nblocks)
+{
+	if (static_branch_likely(&have_extensions)) {
+		kernel_vector_begin();
+		sha256_transform_zvknha_or_zvknhb_zvkb(state, data, nblocks);
+		kernel_vector_end();
+	} else {
+		sha256_blocks_generic(state, data, nblocks);
+	}
+}
+EXPORT_SYMBOL_GPL(sha256_blocks_simd);
+
+void sha256_blocks_arch(u32 state[SHA256_STATE_WORDS],
+			const u8 *data, size_t nblocks)
+{
+	sha256_blocks_generic(state, data, nblocks);
+}
+EXPORT_SYMBOL_GPL(sha256_blocks_arch);
+
+bool sha256_is_arch_optimized(void)
+{
+	return static_key_enabled(&have_extensions);
+}
+EXPORT_SYMBOL_GPL(sha256_is_arch_optimized);
+
+static int __init riscv64_sha256_mod_init(void)
+{
+	/* Both zvknha and zvknhb provide the SHA-256 instructions. */
+	if ((riscv_isa_extension_available(NULL, ZVKNHA) ||
+	     riscv_isa_extension_available(NULL, ZVKNHB)) &&
+	    riscv_isa_extension_available(NULL, ZVKB) &&
+	    riscv_vector_vlen() >= 128)
+		static_branch_enable(&have_extensions);
+	return 0;
+}
+subsys_initcall(riscv64_sha256_mod_init);
+
+static void __exit riscv64_sha256_mod_exit(void)
+{
+}
+module_exit(riscv64_sha256_mod_exit);
+
+MODULE_DESCRIPTION("SHA-256 (RISC-V accelerated)");
+MODULE_AUTHOR("Heiko Stuebner <heiko.stuebner@vrull.eu>");
+MODULE_LICENSE("GPL");