64 lines
1.3 KiB
C
64 lines
1.3 KiB
C
/*
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* Copyright 2008 Freescale Semiconductor, Inc.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* Version 2 as published by the Free Software Foundation.
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*/
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#include <common.h>
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#include <crc.h>
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#include <ddr_spd.h>
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uint32_t ddr2_spd_checksum_pass(const struct ddr2_spd_eeprom_s *spd)
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{
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uint32_t i, cksum = 0;
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const uint8_t *buf = (const uint8_t *)spd;
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uint8_t rev, spd_cksum;
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rev = spd->spd_rev;
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spd_cksum = spd->cksum;
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/* Rev 1.X or less supported by this code */
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if (rev >= 0x20)
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goto error;
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/*
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* The checksum is calculated on the first 64 bytes
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* of the SPD as per JEDEC specification.
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*/
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for (i = 0; i < 63; i++)
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cksum += *buf++;
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cksum &= 0xFF;
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if (cksum != spd_cksum)
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goto error;
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return 0;
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error:
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return 1;
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}
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uint32_t ddr3_spd_checksum_pass(const struct ddr3_spd_eeprom_s *spd)
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{
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char crc_lsb, crc_msb;
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int csum16, len;
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/*
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* SPD byte0[7] - CRC coverage
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* 0 = CRC covers bytes 0~125
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* 1 = CRC covers bytes 0~116
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*/
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len = !(spd->info_size_crc & 0x80) ? 126 : 117;
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csum16 = cyg_crc16((char *)spd, len);
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crc_lsb = (char) (csum16 & 0xff);
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crc_msb = (char) (csum16 >> 8);
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if (spd->crc[0] != crc_lsb || spd->crc[1] != crc_msb)
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return 1;
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return 0;
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}
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