1 files changed, 38 insertions, 0 deletions
diff --git a/src/lib/crc_byte.c b/src/lib/crc_byte.c
new file mode 100644
index 0000000000..0ac006363a
--- /dev/null
+++ b/src/lib/crc_byte.c
@@ -0,0 +1,38 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2019 HardenedLinux
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <crc_byte.h>
+
+uint8_t crc7_byte(uint8_t prev_crc, uint8_t data)
+{
+	const uint8_t g = 0x89;
+	prev_crc ^= data;
+	for (int i = 0; i < 8; i++) {
+		if (prev_crc & 0x80)
+			prev_crc ^= g;
+		prev_crc <<= 1;
+	}
+	return prev_crc;
+}
+
+uint16_t crc16_byte(uint16_t prev_crc, uint8_t data)
+{
+	prev_crc  = (uint8_t)(prev_crc >> 8)|(prev_crc << 8);
+	prev_crc ^=  data;
+	prev_crc ^= (uint8_t)(prev_crc & 0xff) >> 4;
+	prev_crc ^= (prev_crc << 8) << 4;
+	prev_crc ^= ((prev_crc & 0xff) << 4) << 1;
+	return prev_crc;
+}