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Diffstat (limited to 'src/device/dram/ddr_common.c')
-rw-r--r-- | src/device/dram/ddr_common.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/src/device/dram/ddr_common.c b/src/device/dram/ddr_common.c new file mode 100644 index 0000000000..eb36bf52a0 --- /dev/null +++ b/src/device/dram/ddr_common.c @@ -0,0 +1,43 @@ +/* + * 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; +} |