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0f2cbe3f5e
Also adds helper functions for DDR1/2 to verify the checksum. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
62 lines
1.2 KiB
C
62 lines
1.2 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 <ddr_spd.h>
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/* used for ddr1 and ddr2 spd */
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static int
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spd_check(const u8 *buf, u8 spd_rev, u8 spd_cksum)
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{
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unsigned int cksum = 0;
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unsigned int i;
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/*
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* Check SPD revision supported
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* Rev 1.2 or less supported by this code
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*/
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if (spd_rev > 0x12) {
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printf("SPD revision %02X not supported by this code\n",
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spd_rev);
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return 1;
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}
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/*
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* Calculate checksum
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*/
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for (i = 0; i < 63; i++) {
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cksum += *buf++;
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}
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cksum &= 0xFF;
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if (cksum != spd_cksum) {
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printf("SPD checksum unexpected. "
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"Checksum in SPD = %02X, computed SPD = %02X\n",
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spd_cksum, cksum);
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return 1;
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}
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return 0;
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}
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unsigned int
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ddr1_spd_check(const ddr1_spd_eeprom_t *spd)
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{
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const u8 *p = (const u8 *)spd;
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return spd_check(p, spd->spd_rev, spd->cksum);
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}
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unsigned int
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ddr2_spd_check(const ddr2_spd_eeprom_t *spd)
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{
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const u8 *p = (const u8 *)spd;
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return spd_check(p, spd->spd_rev, spd->cksum);
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}
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