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-rw-r--r--src/device/dram/ddr_common.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/src/device/dram/ddr_common.c b/src/device/dram/ddr_common.c
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+++ b/src/device/dram/ddr_common.c
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+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2019 Facebook, Inc.
+ *
+ * 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 <console/console.h>
+#include <device/dram/common.h>
+#include <types.h>
+
+/**
+ * \brief Calculate the CRC of a DDR SPD data
+ *
+ * @param spd pointer to raw SPD data
+ * @param len length of data in SPD
+ *
+ * @return the CRC of the SPD data
+ */
+u16 ddr_crc16(const u8 *ptr, int n_crc)
+{
+ int i;
+ u16 crc = 0;
+
+ while (--n_crc >= 0) {
+ crc = crc ^ ((int)*ptr++ << 8);
+ for (i = 0; i < 8; ++i)
+ if (crc & 0x8000)
+ crc = (crc << 1) ^ 0x1021;
+ else
+ crc = crc << 1;
+ }
+
+ return crc;
+}