/*
* Copyright 2008-2009 Freescale Semiconductor, Inc.
* Dave Liu <daveliu@freescale.com>
*
* calculate the organization and timing parameter
* from ddr3 spd, please refer to the spec
* JEDEC standard No.21-C 4_01_02_11R18.pdf
*
* 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.
*/
#include <common.h>
#include <asm/fsl_ddr_sdram.h>
#include "ddr.h"
/*
* Calculate the Density of each Physical Rank.
* Returned size is in bytes.
*
* each rank size =
* sdram capacity(bit) / 8 * primary bus width / sdram width
*
* where: sdram capacity = spd byte4[3:0]
* primary bus width = spd byte8[2:0]
* sdram width = spd byte7[2:0]
*
* SPD byte4 - sdram density and banks
* bit[3:0] size(bit) size(byte)
* 0000 256Mb 32MB
* 0001 512Mb 64MB
* 0010 1Gb 128MB
* 0011 2Gb 256MB
* 0100 4Gb 512MB
* 0101 8Gb 1GB
* 0110 16Gb 2GB
*
* SPD byte8 - module memory bus width
* bit[2:0] primary bus width
* 000 8bits
* 001 16bits
* 010 32bits
* 011 64bits
*
* SPD byte7 - module organiztion
* bit[2:0] sdram device width
* 000 4bits
* 001 8bits
* 010 16bits
* 011 32bits
*
*/
static unsigned long long
compute_ranksize(const ddr3_spd_eeprom_t *spd)
{
unsigned long long bsize;
int nbit_sdram_cap_bsize = 0;
int nbit_primary_bus_width = 0;
int nbit_sdram_width = 0;
if ((spd->density_banks & 0xf) < 7)
nbit_sdram_cap_bsize = (spd->density_banks & 0xf) + 28;
if ((spd->bus_width & 0x7) < 4)
nbit_primary_bus_width = (spd->bus_width & 0x7) + 3;
if ((spd->organization & 0x7) < 4)
nbit_sdram_width = (spd->organization & 0x7) + 2;
bsize = 1ULL << (nbit_sdram_cap_bsize - 3
+ nbit_primary_bus_width - nbit_sdram_width);
debug("DDR: DDR III rank density = 0x%16llx\n", bsize);
return bsize;
}
/*
* ddr_compute_dimm_parameters for DDR3 SPD
*
* Compute DIMM parameters based upon the SPD information in spd.
* Writes the results to the dimm_params_t structure pointed by pdimm.
*
*/
unsigned int
ddr_compute_dimm_parameters(const ddr3_spd_eeprom_t *spd,
dimm_params_t *pdimm,
unsigned int dimm_number)
{
unsigned int retval;
unsigned int mtb_ps;
int i;
if (spd->mem_type) {
if (spd->mem_type != SPD_MEMTYPE_DDR3) {
printf("DIMM %u: is not a DDR3 SPD.\n", dimm_number);
return 1;
}
} else {
memset(pdimm, 0, sizeof(dimm_params_t));
return 1;
}
retval = ddr3_spd_check(spd);
if (retval) {
printf("DIMM %u: failed checksum\n", dimm_number);
return 2;
}
/*
* The part name in ASCII in the SPD EEPROM is not null terminated.
* Guarantee null termination here by presetting all bytes to 0
* and copying the part name in ASCII from the SPD onto it
*/
memset(pdimm->mpart, 0, sizeof(pdimm->mpart));
if ((spd->info_size_crc & 0xF) > 1)
memcpy(pdimm->mpart, spd->mpart, sizeof(pdimm->mpart) - 1);
/* DIMM organization parameters */
pdimm->n_ranks = ((spd->organization >> 3) & 0x7) + 1;
pdimm->rank_density = compute_ranksize(spd);
pdimm->capacity = pdimm->n_ranks * pdimm->rank_density;
pdimm->primary_sdram_width = 1 << (3 + (spd->bus_width & 0x7));
if ((spd->bus_width >> 3) & 0x3)
pdimm->ec_sdram_width = 8;
else
pdimm->ec_sdram_width = 0;
pdimm->data_width = pdimm->primary_sdram_width
+ pdimm->ec_sdram_width;
/* These are the types defined by the JEDEC DDR3 SPD spec */
pdimm->mirrored_dimm = 0;
pdimm->registered_dimm = 0;
switch (spd->module_type & DDR3_SPD_MODULETYPE_MASK) {
case DDR3_SPD_MODULETYPE_RDIMM:
case DDR3_SPD_MODULETYPE_MINI_RDIMM:
case DDR3_SPD_MODULETYPE_72B_SO_RDIMM:
/* Registered/buffered DIMMs */
pdimm->registered_dimm = 1;
for (i = 0; i < 16; i += 2) {
u8 rcw = spd->mod_section.registered.rcw[i/2];
pdimm->rcw[i] = (rcw >> 0) & 0x0F;
pdimm->rcw[i+1] = (rcw >> 4) & 0x0F;
}
break;
case DDR3_SPD_MODULETYPE_UDIMM:
case DDR3_SPD_MODULETYPE_SO_DIMM:
case DDR3_SPD_MODULETYPE_MICRO_DIMM:
case DDR3_SPD_MODULETYPE_MINI_UDIMM:
case DDR3_SPD_MODULETYPE_MINI_CDIMM:
case DDR3_SPD_MODULETYPE_72B_SO_UDIMM:
case DDR3_SPD_MODULETYPE_72B_SO_CDIMM:
case DDR3_SPD_MODULETYPE_LRDIMM:
case DDR3_SPD_MODULETYPE_16B_SO_DIMM:
case DDR3_SPD_MODULETYPE_32B_SO_DIMM:
/* Unbuffered DIMMs */
if (spd->mod_section.unbuffered.addr_mapping & 0x1)
pdimm->mirrored_dimm = 1;
break;
default:
printf("unknown module_type 0x%02X\n", spd->module_type);
return 1;
}
/* SDRAM device parameters */
pdimm->n_row_addr = ((spd->addressing >> 3) & 0x7) + 12;
pdimm->n_col_addr = (spd->addressing & 0x7) + 9;
pdimm->n_banks_per_sdram_device = 8 << ((spd->density_banks >> 4) & 0x7);
/*
* The SPD spec has not the ECC bit,
* We consider the DIMM as ECC capability
* when the extension bus exist
*/
if (pdimm->ec_sdram_width)
pdimm->edc_config = 0x02;
else
pdimm->edc_config = 0x00;
/*
* The SPD spec has not the burst length byte
* but DDR3 spec has nature BL8 and BC4,
* BL8 -bit3, BC4 -bit2
*/
pdimm->burst_lengths_bitmask = 0x0c;
pdimm->row_density = __ilog2(pdimm->rank_density);
/* MTB - medium timebase
* The unit in the SPD spec is ns,
* We convert it to ps.
* eg: MTB = 0.125ns (125ps)
*/
mtb_ps = (spd->mtb_dividend * 1000) /spd->mtb_divisor;
pdimm->mtb_ps = mtb_ps;
/*
* sdram minimum cycle time
* we assume the MTB is 0.125ns
* eg:
* tCK_min=15 MTB (1.875ns) ->DDR3-1066
* =12 MTB (1.5ns) ->DDR3-1333
* =10 MTB (1.25ns) ->DDR3-1600
*/
pdimm->tCKmin_X_ps = spd->tCK_min * mtb_ps;
/*
* CAS latency supported
* bit4 - CL4
* bit5 - CL5
* bit18 - CL18
*/
pdimm->caslat_X = ((spd->caslat_msb << 8) | spd->caslat_lsb) << 4;
/*
* min CAS latency time
* eg: tAA_min =
* DDR3-800D 100 MTB (12.5ns)
* DDR3-1066F 105 MTB (13.125ns)
* DDR3-1333H 108 MTB (13.5ns)
* DDR3-1600H 90 MTB (11.25ns)
*/
pdimm->tAA_ps = spd->tAA_min * mtb_ps;
/*
* min write recovery time
* eg:
* tWR_min = 120 MTB (15ns) -> all speed grades.
*/
pdimm->tWR_ps = spd->tWR_min * mtb_ps;
/*
* min RAS to CAS delay time
* eg: tRCD_min =
* DDR3-800 100 MTB (12.5ns)
* DDR3-1066F 105 MTB (13.125ns)
* DDR3-1333H 108 MTB (13.5ns)
* DDR3-1600H 90 MTB (11.25)
*/
pdimm->tRCD_ps = spd->tRCD_min * mtb_ps;
/*
* min row active to row active delay time
* eg: tRRD_min =
* DDR3-800(1KB page) 80 MTB (10ns)
* DDR3-1333(1KB page) 48 MTB (6ns)
*/
pdimm->tRRD_ps = spd->tRRD_min * mtb_ps;
/*
* min row precharge delay time
* eg: tRP_min =
* DDR3-800D 100 MTB (12.5ns)
* DDR3-1066F 105 MTB (13.125ns)
* DDR3-1333H 108 MTB (13.5ns)
* DDR3-1600H 90 MTB (11.25ns)
*/
pdimm->tRP_ps = spd->tRP_min * mtb_ps;
/* min active to precharge delay time
* eg: tRAS_min =
* DDR3-800D 300 MTB (37.5ns)
* DDR3-1066F 300 MTB (37.5ns)
* DDR3-1333H 288 MTB (36ns)
* DDR3-1600H 280 MTB (35ns)
*/
pdimm->tRAS_ps = (((spd->tRAS_tRC_ext & 0xf) << 8) | spd->tRAS_min_lsb)
* mtb_ps;
/*
* min active to actice/refresh delay time
* eg: tRC_min =
* DDR3-800D 400 MTB (50ns)
* DDR3-1066F 405 MTB (50.625ns)
* DDR3-1333H 396 MTB (49.5ns)
* DDR3-1600H 370 MTB (46.25ns)
*/
pdimm->tRC_ps = (((spd->tRAS_tRC_ext & 0xf0) << 4) | spd->tRC_min_lsb)
* mtb_ps;
/*
* min refresh recovery delay time
* eg: tRFC_min =
* 512Mb 720 MTB (90ns)
* 1Gb 880 MTB (110ns)
* 2Gb 1280 MTB (160ns)
*/
pdimm->tRFC_ps = ((spd->tRFC_min_msb << 8) | spd->tRFC_min_lsb)
* mtb_ps;
/*
* min internal write to read command delay time
* eg: tWTR_min = 40 MTB (7.5ns) - all speed bins.
* tWRT is at least 4 mclk independent of operating freq.
*/
pdimm->tWTR_ps = spd->tWTR_min * mtb_ps;
/*
* min internal read to precharge command delay time
* eg: tRTP_min = 40 MTB (7.5ns) - all speed bins.
* tRTP is at least 4 mclk independent of operating freq.
*/
pdimm->tRTP_ps = spd->tRTP_min * mtb_ps;
/*
* Average periodic refresh interval
* tREFI = 7.8 us at normal temperature range
* = 3.9 us at ext temperature range
*/
pdimm->refresh_rate_ps = 7800000;
/*
* min four active window delay time
* eg: tFAW_min =
* DDR3-800(1KB page) 320 MTB (40ns)
* DDR3-1066(1KB page) 300 MTB (37.5ns)
* DDR3-1333(1KB page) 240 MTB (30ns)
* DDR3-1600(1KB page) 240 MTB (30ns)
*/
pdimm->tFAW_ps = (((spd->tFAW_msb & 0xf) << 8) | spd->tFAW_min)
* mtb_ps;
return 0;
}