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/*
* Copyright 2008 Freescale Semiconductor, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* Version 2 as published by the Free Software Foundation.
*/
#ifndef DDR2_DIMM_PARAMS_H
#define DDR2_DIMM_PARAMS_H
/* Parameters for a DDR2 dimm computed from the SPD */
typedef struct dimm_params_s {
/* DIMM organization parameters */
char mpart[19]; /* guaranteed null terminated */
unsigned int n_ranks;
unsigned long long rank_density;
unsigned long long capacity;
unsigned int data_width;
unsigned int primary_sdram_width;
unsigned int ec_sdram_width;
unsigned int registered_dimm;
/* SDRAM device parameters */
unsigned int n_row_addr;
unsigned int n_col_addr;
unsigned int edc_config; /* 0 = none, 1 = parity, 2 = ECC */
unsigned int n_banks_per_sdram_device;
unsigned int burst_lengths_bitmask; /* BL=4 bit 2, BL=8 = bit 3 */
unsigned int row_density;
/* used in computing base address of DIMMs */
unsigned long long base_address;
/* DIMM timing parameters */
/*
* SDRAM clock periods
* The range for these are 1000-10000 so a short should be sufficient
*/
unsigned int tCKmin_X_ps;
unsigned int tCKmin_X_minus_1_ps;
unsigned int tCKmin_X_minus_2_ps;
unsigned int tCKmax_ps;
/* SPD-defined CAS latencies */
unsigned int caslat_X;
unsigned int caslat_X_minus_1;
unsigned int caslat_X_minus_2;
unsigned int caslat_lowest_derated; /* Derated CAS latency */
/* basic timing parameters */
unsigned int tRCD_ps;
unsigned int tRP_ps;
unsigned int tRAS_ps;
unsigned int tWR_ps; /* maximum = 63750 ps */
unsigned int tWTR_ps; /* maximum = 63750 ps */
unsigned int tRFC_ps; /* max = 255 ns + 256 ns + .75 ns
= 511750 ps */
unsigned int tRRD_ps; /* maximum = 63750 ps */
unsigned int tRC_ps; /* maximum = 254 ns + .75 ns = 254750 ps */
unsigned int refresh_rate_ps;
unsigned int tIS_ps; /* byte 32, spd->ca_setup */
unsigned int tIH_ps; /* byte 33, spd->ca_hold */
unsigned int tDS_ps; /* byte 34, spd->data_setup */
unsigned int tDH_ps; /* byte 35, spd->data_hold */
unsigned int tRTP_ps; /* byte 38, spd->trtp */
unsigned int tDQSQ_max_ps; /* byte 44, spd->tdqsq */
unsigned int tQHS_ps; /* byte 45, spd->tqhs */
} dimm_params_t;
extern unsigned int ddr_compute_dimm_parameters(
const generic_spd_eeprom_t *spd,
dimm_params_t *pdimm,
unsigned int dimm_number);
#endif
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