1 files changed, 85 insertions, 0 deletions
diff --git a/lib/crc/arm64/crc32.h b/lib/crc/arm64/crc32.h
new file mode 100644
index 000000000000..1939a5dee477
--- /dev/null
+++ b/lib/crc/arm64/crc32.h
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <asm/alternative.h>
+#include <asm/cpufeature.h>
+#include <asm/simd.h>
+
+// The minimum input length to consider the 4-way interleaved code path
+static const size_t min_len = 1024;
+
+asmlinkage u32 crc32_le_arm64(u32 crc, unsigned char const *p, size_t len);
+asmlinkage u32 crc32c_le_arm64(u32 crc, unsigned char const *p, size_t len);
+asmlinkage u32 crc32_be_arm64(u32 crc, unsigned char const *p, size_t len);
+
+asmlinkage u32 crc32_le_arm64_4way(u32 crc, unsigned char const *p, size_t len);
+asmlinkage u32 crc32c_le_arm64_4way(u32 crc, unsigned char const *p, size_t len);
+asmlinkage u32 crc32_be_arm64_4way(u32 crc, unsigned char const *p, size_t len);
+
+static inline u32 crc32_le_arch(u32 crc, const u8 *p, size_t len)
+{
+	if (!alternative_has_cap_likely(ARM64_HAS_CRC32))
+		return crc32_le_base(crc, p, len);
+
+	if (len >= min_len && cpu_have_named_feature(PMULL) &&
+	    likely(may_use_simd())) {
+		scoped_ksimd()
+			crc = crc32_le_arm64_4way(crc, p, len);
+
+		p += round_down(len, 64);
+		len %= 64;
+
+		if (!len)
+			return crc;
+	}
+
+	return crc32_le_arm64(crc, p, len);
+}
+
+static inline u32 crc32c_arch(u32 crc, const u8 *p, size_t len)
+{
+	if (!alternative_has_cap_likely(ARM64_HAS_CRC32))
+		return crc32c_base(crc, p, len);
+
+	if (len >= min_len && cpu_have_named_feature(PMULL) &&
+	    likely(may_use_simd())) {
+		scoped_ksimd()
+			crc = crc32c_le_arm64_4way(crc, p, len);
+
+		p += round_down(len, 64);
+		len %= 64;
+
+		if (!len)
+			return crc;
+	}
+
+	return crc32c_le_arm64(crc, p, len);
+}
+
+static inline u32 crc32_be_arch(u32 crc, const u8 *p, size_t len)
+{
+	if (!alternative_has_cap_likely(ARM64_HAS_CRC32))
+		return crc32_be_base(crc, p, len);
+
+	if (len >= min_len && cpu_have_named_feature(PMULL) &&
+	    likely(may_use_simd())) {
+		scoped_ksimd()
+			crc = crc32_be_arm64_4way(crc, p, len);
+
+		p += round_down(len, 64);
+		len %= 64;
+
+		if (!len)
+			return crc;
+	}
+
+	return crc32_be_arm64(crc, p, len);
+}
+
+static inline u32 crc32_optimizations_arch(void)
+{
+	if (alternative_has_cap_likely(ARM64_HAS_CRC32))
+		return CRC32_LE_OPTIMIZATION |
+		       CRC32_BE_OPTIMIZATION |
+		       CRC32C_OPTIMIZATION;
+	return 0;
+}