2 * Copyright 2014 Freescale Semiconductor, Inc.
4 * calculate the organization and timing parameter
5 * from ddr3 spd, please refer to the spec
6 * JEDEC standard No.21-C 4_01_02_12R23A.pdf
12 #include <fsl_ddr_sdram.h>
17 * Calculate the Density of each Physical Rank.
18 * Returned size is in bytes.
21 * sdram capacity(bit) / 8 * primary bus width / sdram width
22 * * Logical Ranks per DIMM
24 * where: sdram capacity = spd byte4[3:0]
25 * primary bus width = spd byte13[2:0]
26 * sdram width = spd byte12[2:0]
27 * Logical Ranks per DIMM = spd byte12[5:3] for SDP, DDP, QDP
28 * spd byte12{5:3] * spd byte6[6:4] for 3DS
30 * To simplify each rank size = total DIMM size / Number of Package Ranks
31 * where Number of Package Ranks = spd byte12[5:3]
33 * SPD byte4 - sdram density and banks
34 * bit[3:0] size(bit) size(byte)
44 * SPD byte13 - module memory bus width
45 * bit[2:0] primary bus width
51 * SPD byte12 - module organization
52 * bit[2:0] sdram device width
58 * SPD byte12 - module organization
59 * bit[5:3] number of package ranks per DIMM
65 * SPD byte6 - SDRAM package type
76 * SPD byte6 - SRAM package type
77 * bit[1:0] Signal loading
80 * 10 Sigle load stack (3DS)
83 static unsigned long long
84 compute_ranksize(const struct ddr4_spd_eeprom_s
*spd
)
86 unsigned long long bsize
;
88 int nbit_sdram_cap_bsize
= 0;
89 int nbit_primary_bus_width
= 0;
90 int nbit_sdram_width
= 0;
94 if ((spd
->density_banks
& 0xf) <= 7)
95 nbit_sdram_cap_bsize
= (spd
->density_banks
& 0xf) + 28;
96 if ((spd
->bus_width
& 0x7) < 4)
97 nbit_primary_bus_width
= (spd
->bus_width
& 0x7) + 3;
98 if ((spd
->organization
& 0x7) < 4)
99 nbit_sdram_width
= (spd
->organization
& 0x7) + 2;
100 package_3ds
= (spd
->package_type
& 0x3) == 0x2;
102 die_count
= (spd
->package_type
>> 4) & 0x7;
104 bsize
= 1ULL << (nbit_sdram_cap_bsize
- 3 +
105 nbit_primary_bus_width
- nbit_sdram_width
+
108 debug("DDR: DDR III rank density = 0x%16llx\n", bsize
);
113 #define spd_to_ps(mtb, ftb) \
114 (mtb * pdimm->mtb_ps + (ftb * pdimm->ftb_10th_ps) / 10)
116 * ddr_compute_dimm_parameters for DDR4 SPD
118 * Compute DIMM parameters based upon the SPD information in spd.
119 * Writes the results to the dimm_params_t structure pointed by pdimm.
122 unsigned int ddr_compute_dimm_parameters(const unsigned int ctrl_num
,
123 const generic_spd_eeprom_t
*spd
,
124 dimm_params_t
*pdimm
,
125 unsigned int dimm_number
)
129 const u8 udimm_rc_e_dq
[18] = {
130 0x0c, 0x2c, 0x15, 0x35, 0x15, 0x35, 0x0b, 0x2c, 0x15,
131 0x35, 0x0b, 0x35, 0x0b, 0x2c, 0x0b, 0x35, 0x15, 0x36
137 if (spd
->mem_type
!= SPD_MEMTYPE_DDR4
) {
138 printf("Ctrl %u DIMM %u: is not a DDR4 SPD.\n",
139 ctrl_num
, dimm_number
);
143 memset(pdimm
, 0, sizeof(dimm_params_t
));
147 retval
= ddr4_spd_check(spd
);
149 printf("DIMM %u: failed checksum\n", dimm_number
);
154 * The part name in ASCII in the SPD EEPROM is not null terminated.
155 * Guarantee null termination here by presetting all bytes to 0
156 * and copying the part name in ASCII from the SPD onto it
158 memset(pdimm
->mpart
, 0, sizeof(pdimm
->mpart
));
159 if ((spd
->info_size_crc
& 0xF) > 2)
160 memcpy(pdimm
->mpart
, spd
->mpart
, sizeof(pdimm
->mpart
) - 1);
162 /* DIMM organization parameters */
163 pdimm
->n_ranks
= ((spd
->organization
>> 3) & 0x7) + 1;
164 pdimm
->rank_density
= compute_ranksize(spd
);
165 pdimm
->capacity
= pdimm
->n_ranks
* pdimm
->rank_density
;
166 pdimm
->primary_sdram_width
= 1 << (3 + (spd
->bus_width
& 0x7));
167 if ((spd
->bus_width
>> 3) & 0x3)
168 pdimm
->ec_sdram_width
= 8;
170 pdimm
->ec_sdram_width
= 0;
171 pdimm
->data_width
= pdimm
->primary_sdram_width
172 + pdimm
->ec_sdram_width
;
173 pdimm
->device_width
= 1 << ((spd
->organization
& 0x7) + 2);
175 /* These are the types defined by the JEDEC SPD spec */
176 pdimm
->mirrored_dimm
= 0;
177 pdimm
->registered_dimm
= 0;
178 switch (spd
->module_type
& DDR4_SPD_MODULETYPE_MASK
) {
179 case DDR4_SPD_MODULETYPE_RDIMM
:
180 /* Registered/buffered DIMMs */
181 pdimm
->registered_dimm
= 1;
184 case DDR4_SPD_MODULETYPE_UDIMM
:
185 case DDR4_SPD_MODULETYPE_SO_DIMM
:
186 /* Unbuffered DIMMs */
187 if (spd
->mod_section
.unbuffered
.addr_mapping
& 0x1)
188 pdimm
->mirrored_dimm
= 1;
189 if ((spd
->mod_section
.unbuffered
.mod_height
& 0xe0) == 0 &&
190 (spd
->mod_section
.unbuffered
.ref_raw_card
== 0x04)) {
191 /* Fix SPD error found on DIMMs with raw card E0 */
192 for (i
= 0; i
< 18; i
++) {
193 if (spd
->mapping
[i
] == udimm_rc_e_dq
[i
])
196 debug("SPD byte %d: 0x%x, should be 0x%x\n",
197 60 + i
, spd
->mapping
[i
],
199 ptr
= (u8
*)&spd
->mapping
[i
];
200 *ptr
= udimm_rc_e_dq
[i
];
203 puts("SPD DQ mapping error fixed\n");
208 printf("unknown module_type 0x%02X\n", spd
->module_type
);
212 /* SDRAM device parameters */
213 pdimm
->n_row_addr
= ((spd
->addressing
>> 3) & 0x7) + 12;
214 pdimm
->n_col_addr
= (spd
->addressing
& 0x7) + 9;
215 pdimm
->bank_addr_bits
= (spd
->density_banks
>> 4) & 0x3;
216 pdimm
->bank_group_bits
= (spd
->density_banks
>> 6) & 0x3;
219 * The SPD spec has not the ECC bit,
220 * We consider the DIMM as ECC capability
221 * when the extension bus exist
223 if (pdimm
->ec_sdram_width
)
224 pdimm
->edc_config
= 0x02;
226 pdimm
->edc_config
= 0x00;
229 * The SPD spec has not the burst length byte
230 * but DDR4 spec has nature BL8 and BC4,
231 * BL8 -bit3, BC4 -bit2
233 pdimm
->burst_lengths_bitmask
= 0x0c;
234 pdimm
->row_density
= __ilog2(pdimm
->rank_density
);
236 /* MTB - medium timebase
237 * The MTB in the SPD spec is 125ps,
239 * FTB - fine timebase
240 * use 1/10th of ps as our unit to avoid floating point
241 * eg, 10 for 1ps, 25 for 2.5ps, 50 for 5ps
243 if ((spd
->timebases
& 0xf) == 0x0) {
245 pdimm
->ftb_10th_ps
= 10;
248 printf("Unknown Timebases\n");
251 /* sdram minimum cycle time */
252 pdimm
->tckmin_x_ps
= spd_to_ps(spd
->tck_min
, spd
->fine_tck_min
);
254 /* sdram max cycle time */
255 pdimm
->tckmax_ps
= spd_to_ps(spd
->tck_max
, spd
->fine_tck_max
);
258 * CAS latency supported
265 pdimm
->caslat_x
= (spd
->caslat_b1
<< 7) |
266 (spd
->caslat_b2
<< 15) |
267 (spd
->caslat_b3
<< 23);
269 BUG_ON(spd
->caslat_b4
!= 0);
272 * min CAS latency time
274 pdimm
->taa_ps
= spd_to_ps(spd
->taa_min
, spd
->fine_taa_min
);
277 * min RAS to CAS delay time
279 pdimm
->trcd_ps
= spd_to_ps(spd
->trcd_min
, spd
->fine_trcd_min
);
282 * Min Row Precharge Delay Time
284 pdimm
->trp_ps
= spd_to_ps(spd
->trp_min
, spd
->fine_trp_min
);
286 /* min active to precharge delay time */
287 pdimm
->tras_ps
= (((spd
->tras_trc_ext
& 0xf) << 8) +
288 spd
->tras_min_lsb
) * pdimm
->mtb_ps
;
290 /* min active to actice/refresh delay time */
291 pdimm
->trc_ps
= spd_to_ps((((spd
->tras_trc_ext
& 0xf0) << 4) +
292 spd
->trc_min_lsb
), spd
->fine_trc_min
);
293 /* Min Refresh Recovery Delay Time */
294 pdimm
->trfc1_ps
= ((spd
->trfc1_min_msb
<< 8) | (spd
->trfc1_min_lsb
)) *
296 pdimm
->trfc2_ps
= ((spd
->trfc2_min_msb
<< 8) | (spd
->trfc2_min_lsb
)) *
298 pdimm
->trfc4_ps
= ((spd
->trfc4_min_msb
<< 8) | (spd
->trfc4_min_lsb
)) *
300 /* min four active window delay time */
301 pdimm
->tfaw_ps
= (((spd
->tfaw_msb
& 0xf) << 8) | spd
->tfaw_min
) *
304 /* min row active to row active delay time, different bank group */
305 pdimm
->trrds_ps
= spd_to_ps(spd
->trrds_min
, spd
->fine_trrds_min
);
306 /* min row active to row active delay time, same bank group */
307 pdimm
->trrdl_ps
= spd_to_ps(spd
->trrdl_min
, spd
->fine_trrdl_min
);
308 /* min CAS to CAS Delay Time (tCCD_Lmin), same bank group */
309 pdimm
->tccdl_ps
= spd_to_ps(spd
->tccdl_min
, spd
->fine_tccdl_min
);
312 * Average periodic refresh interval
313 * tREFI = 7.8 us at normal temperature range
315 pdimm
->refresh_rate_ps
= 7800000;
317 for (i
= 0; i
< 18; i
++)
318 pdimm
->dq_mapping
[i
] = spd
->mapping
[i
];
320 pdimm
->dq_mapping_ors
= ((spd
->mapping
[0] >> 6) & 0x3) == 0 ? 1 : 0;