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/*
* Copyright 2014 Freescale Semiconductor, Inc.
*
* calculate the organization and timing parameter
* from ddr3 spd, please refer to the spec
* JEDEC standard No.21-C 4_01_02_12R23A.pdf
*
*
*/
#include <common.h>
#include <fsl_ddr_sdram.h>
#include <fsl_ddr.h>
/*
* Calculate the Density of each Physical Rank.
* Returned size is in bytes.
*
* Total DIMM size =
* sdram capacity(bit) / 8 * primary bus width / sdram width
* * Logical Ranks per DIMM
*
* where: sdram capacity = spd byte4[3:0]
* primary bus width = spd byte13[2:0]
* sdram width = spd byte12[2:0]
* Logical Ranks per DIMM = spd byte12[5:3] for SDP, DDP, QDP
* spd byte12{5:3] * spd byte6[6:4] for 3DS
*
* To simplify each rank size = total DIMM size / Number of Package Ranks
* where Number of Package Ranks = spd byte12[5:3]
*
* 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
* 0111 32Gb 4GB
*
* SPD byte13 - module memory bus width
* bit[2:0] primary bus width
* 000 8bits
* 001 16bits
* 010 32bits
* 011 64bits
*
* SPD byte12 - module organization
* bit[2:0] sdram device width
* 000 4bits
* 001 8bits
* 010 16bits
* 011 32bits
*
* SPD byte12 - module organization
* bit[5:3] number of package ranks per DIMM
* 000 1
* 001 2
* 010 3
* 011 4
*
* SPD byte6 - SDRAM package type
* bit[6:4] Die count
* 000 1
* 001 2
* 010 3
* 011 4
* 100 5
* 101 6
* 110 7
* 111 8
*
* SPD byte6 - SRAM package type
* bit[1:0] Signal loading
* 00 Not specified
* 01 Multi load stack
* 10 Sigle load stack (3DS)
* 11 Reserved
*/
static unsigned long long
compute_ranksize(const struct ddr4_spd_eeprom_s *spd)
{
unsigned long long bsize;
int nbit_sdram_cap_bsize = 0;
int nbit_primary_bus_width = 0;
int nbit_sdram_width = 0;
int die_count = 0;
bool package_3ds;
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;
package_3ds = (spd->package_type & 0x3) == 0x2;
if (package_3ds)
die_count = (spd->package_type >> 4) & 0x7;
bsize = 1ULL << (nbit_sdram_cap_bsize - 3 +
nbit_primary_bus_width - nbit_sdram_width +
die_count);
debug("DDR: DDR III rank density = 0x%16llx\n", bsize);
return bsize;
}
#define spd_to_ps(mtb, ftb) \
(mtb * pdimm->mtb_ps + (ftb * pdimm->ftb_10th_ps) / 10)
/*
* 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 generic_spd_eeprom_t *spd,
dimm_params_t *pdimm,
unsigned int dimm_number)
{
unsigned int retval;
int i;
if (spd->mem_type) {
if (spd->mem_type != SPD_MEMTYPE_DDR4) {
printf("DIMM %u: is not a DDR4 SPD.\n", dimm_number);
return 1;
}
} else {
memset(pdimm, 0, sizeof(dimm_params_t));
return 1;
}
retval = ddr4_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) > 2)
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;
pdimm->device_width = 1 << ((spd->organization & 0x7) + 2);
/* 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:
/* Registered/buffered DIMMs */
pdimm->registered_dimm = 1;
break;
case DDR3_SPD_MODULETYPE_UDIMM:
case DDR3_SPD_MODULETYPE_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->bank_addr_bits = (spd->density_banks >> 4) & 0x3;
pdimm->bank_group_bits = (spd->density_banks >> 6) & 0x3;
/*
* 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 DDR4 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 MTB in the SPD spec is 125ps,
*
* FTB - fine timebase
* use 1/10th of ps as our unit to avoid floating point
* eg, 10 for 1ps, 25 for 2.5ps, 50 for 5ps
*/
if ((spd->timebases & 0xf) == 0x0) {
pdimm->mtb_ps = 125;
pdimm->ftb_10th_ps = 10;
} else {
printf("Unknown Timebases\n");
}
/* sdram minimum cycle time */
pdimm->tckmin_x_ps = spd_to_ps(spd->tck_min, spd->fine_tck_min);
/* sdram max cycle time */
pdimm->tckmax_ps = spd_to_ps(spd->tck_max, spd->fine_tck_max);
/*
* CAS latency supported
* bit0 - CL7
* bit4 - CL11
* bit8 - CL15
* bit12- CL19
* bit16- CL23
*/
pdimm->caslat_x = (spd->caslat_b1 << 7) |
(spd->caslat_b2 << 15) |
(spd->caslat_b3 << 23);
BUG_ON(spd->caslat_b4 != 0);
/*
* min CAS latency time
*/
pdimm->taa_ps = spd_to_ps(spd->taa_min, spd->fine_taa_min);
/*
* min RAS to CAS delay time
*/
pdimm->trcd_ps = spd_to_ps(spd->trcd_min, spd->fine_trcd_min);
/*
* Min Row Precharge Delay Time
*/
pdimm->trp_ps = spd_to_ps(spd->trp_min, spd->fine_trp_min);
/* min active to precharge delay time */
pdimm->tras_ps = (((spd->tras_trc_ext & 0xf) << 8) +
spd->tras_min_lsb) * pdimm->mtb_ps;
/* min active to actice/refresh delay time */
pdimm->trc_ps = spd_to_ps((((spd->tras_trc_ext & 0xf0) << 4) +
spd->trc_min_lsb), spd->fine_trc_min);
/* Min Refresh Recovery Delay Time */
pdimm->trfc1_ps = ((spd->trfc1_min_msb << 8) | (spd->trfc1_min_lsb)) *
pdimm->mtb_ps;
pdimm->trfc2_ps = ((spd->trfc2_min_msb << 8) | (spd->trfc2_min_lsb)) *
pdimm->mtb_ps;
pdimm->trfc4_ps = ((spd->trfc4_min_msb << 8) | (spd->trfc4_min_lsb)) *
pdimm->mtb_ps;
/* min four active window delay time */
pdimm->tfaw_ps = (((spd->tfaw_msb & 0xf) << 8) | spd->tfaw_min) *
pdimm->mtb_ps;
/* min row active to row active delay time, different bank group */
pdimm->trrds_ps = spd_to_ps(spd->trrds_min, spd->fine_trrds_min);
/* min row active to row active delay time, same bank group */
pdimm->trrdl_ps = spd_to_ps(spd->trrdl_min, spd->fine_trrdl_min);
/* min CAS to CAS Delay Time (tCCD_Lmin), same bank group */
pdimm->tccdl_ps = spd_to_ps(spd->tccdl_min, spd->fine_tccdl_min);
/*
* Average periodic refresh interval
* tREFI = 7.8 us at normal temperature range
*/
pdimm->refresh_rate_ps = 7800000;
for (i = 0; i < 18; i++)
pdimm->dq_mapping[i] = spd->mapping[i];
pdimm->dq_mapping_ors = ((spd->mapping[0] >> 6) & 0x3) == 0 ? 1 : 0;
return 0;
}
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