1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright 2008-2012 Freescale Semiconductor, Inc.
4  *	Dave Liu <daveliu@freescale.com>
5  *
6  * calculate the organization and timing parameter
7  * from ddr3 spd, please refer to the spec
8  * JEDEC standard No.21-C 4_01_02_11R18.pdf
9  */
10 
11 #include <common.h>
12 #include <fsl_ddr_sdram.h>
13 
14 #include <fsl_ddr.h>
15 
16 /*
17  * Calculate the Density of each Physical Rank.
18  * Returned size is in bytes.
19  *
20  * each rank size =
21  * sdram capacity(bit) / 8 * primary bus width / sdram width
22  *
23  * where: sdram capacity  = spd byte4[3:0]
24  *        primary bus width = spd byte8[2:0]
25  *        sdram width = spd byte7[2:0]
26  *
27  * SPD byte4 - sdram density and banks
28  *	bit[3:0]	size(bit)	size(byte)
29  *	0000		256Mb		32MB
30  *	0001		512Mb		64MB
31  *	0010		1Gb		128MB
32  *	0011		2Gb		256MB
33  *	0100		4Gb		512MB
34  *	0101		8Gb		1GB
35  *	0110		16Gb		2GB
36  *
37  * SPD byte8 - module memory bus width
38  * 	bit[2:0]	primary bus width
39  *	000		8bits
40  * 	001		16bits
41  * 	010		32bits
42  * 	011		64bits
43  *
44  * SPD byte7 - module organiztion
45  * 	bit[2:0]	sdram device width
46  * 	000		4bits
47  * 	001		8bits
48  * 	010		16bits
49  * 	011		32bits
50  *
51  */
52 static unsigned long long
53 compute_ranksize(const ddr3_spd_eeprom_t *spd)
54 {
55 	unsigned long long bsize;
56 
57 	int nbit_sdram_cap_bsize = 0;
58 	int nbit_primary_bus_width = 0;
59 	int nbit_sdram_width = 0;
60 
61 	if ((spd->density_banks & 0xf) < 7)
62 		nbit_sdram_cap_bsize = (spd->density_banks & 0xf) + 28;
63 	if ((spd->bus_width & 0x7) < 4)
64 		nbit_primary_bus_width = (spd->bus_width & 0x7) + 3;
65 	if ((spd->organization & 0x7) < 4)
66 		nbit_sdram_width = (spd->organization & 0x7) + 2;
67 
68 	bsize = 1ULL << (nbit_sdram_cap_bsize - 3
69 		    + nbit_primary_bus_width - nbit_sdram_width);
70 
71 	debug("DDR: DDR III rank density = 0x%16llx\n", bsize);
72 
73 	return bsize;
74 }
75 
76 /*
77  * ddr_compute_dimm_parameters for DDR3 SPD
78  *
79  * Compute DIMM parameters based upon the SPD information in spd.
80  * Writes the results to the dimm_params_t structure pointed by pdimm.
81  *
82  */
83 unsigned int ddr_compute_dimm_parameters(const unsigned int ctrl_num,
84 					 const ddr3_spd_eeprom_t *spd,
85 					 dimm_params_t *pdimm,
86 					 unsigned int dimm_number)
87 {
88 	unsigned int retval;
89 	unsigned int mtb_ps;
90 	int ftb_10th_ps;
91 	int i;
92 
93 	if (spd->mem_type) {
94 		if (spd->mem_type != SPD_MEMTYPE_DDR3) {
95 			printf("DIMM %u: is not a DDR3 SPD.\n", dimm_number);
96 			return 1;
97 		}
98 	} else {
99 		memset(pdimm, 0, sizeof(dimm_params_t));
100 		return 1;
101 	}
102 
103 	retval = ddr3_spd_check(spd);
104 	if (retval) {
105 		printf("DIMM %u: failed checksum\n", dimm_number);
106 		return 2;
107 	}
108 
109 	/*
110 	 * The part name in ASCII in the SPD EEPROM is not null terminated.
111 	 * Guarantee null termination here by presetting all bytes to 0
112 	 * and copying the part name in ASCII from the SPD onto it
113 	 */
114 	memset(pdimm->mpart, 0, sizeof(pdimm->mpart));
115 	if ((spd->info_size_crc & 0xF) > 1)
116 		memcpy(pdimm->mpart, spd->mpart, sizeof(pdimm->mpart) - 1);
117 
118 	/* DIMM organization parameters */
119 	pdimm->n_ranks = ((spd->organization >> 3) & 0x7) + 1;
120 	pdimm->rank_density = compute_ranksize(spd);
121 	pdimm->capacity = pdimm->n_ranks * pdimm->rank_density;
122 	pdimm->primary_sdram_width = 1 << (3 + (spd->bus_width & 0x7));
123 	if ((spd->bus_width >> 3) & 0x3)
124 		pdimm->ec_sdram_width = 8;
125 	else
126 		pdimm->ec_sdram_width = 0;
127 	pdimm->data_width = pdimm->primary_sdram_width
128 			  + pdimm->ec_sdram_width;
129 	pdimm->device_width = 1 << ((spd->organization & 0x7) + 2);
130 
131 	/* These are the types defined by the JEDEC DDR3 SPD spec */
132 	pdimm->mirrored_dimm = 0;
133 	pdimm->registered_dimm = 0;
134 	switch (spd->module_type & DDR3_SPD_MODULETYPE_MASK) {
135 	case DDR3_SPD_MODULETYPE_RDIMM:
136 	case DDR3_SPD_MODULETYPE_MINI_RDIMM:
137 	case DDR3_SPD_MODULETYPE_72B_SO_RDIMM:
138 		/* Registered/buffered DIMMs */
139 		pdimm->registered_dimm = 1;
140 		for (i = 0; i < 16; i += 2) {
141 			u8 rcw = spd->mod_section.registered.rcw[i/2];
142 			pdimm->rcw[i]   = (rcw >> 0) & 0x0F;
143 			pdimm->rcw[i+1] = (rcw >> 4) & 0x0F;
144 		}
145 		break;
146 
147 	case DDR3_SPD_MODULETYPE_UDIMM:
148 	case DDR3_SPD_MODULETYPE_SO_DIMM:
149 	case DDR3_SPD_MODULETYPE_MICRO_DIMM:
150 	case DDR3_SPD_MODULETYPE_MINI_UDIMM:
151 	case DDR3_SPD_MODULETYPE_MINI_CDIMM:
152 	case DDR3_SPD_MODULETYPE_72B_SO_UDIMM:
153 	case DDR3_SPD_MODULETYPE_72B_SO_CDIMM:
154 	case DDR3_SPD_MODULETYPE_LRDIMM:
155 	case DDR3_SPD_MODULETYPE_16B_SO_DIMM:
156 	case DDR3_SPD_MODULETYPE_32B_SO_DIMM:
157 		/* Unbuffered DIMMs */
158 		if (spd->mod_section.unbuffered.addr_mapping & 0x1)
159 			pdimm->mirrored_dimm = 1;
160 		break;
161 
162 	default:
163 		printf("unknown module_type 0x%02X\n", spd->module_type);
164 		return 1;
165 	}
166 
167 	/* SDRAM device parameters */
168 	pdimm->n_row_addr = ((spd->addressing >> 3) & 0x7) + 12;
169 	pdimm->n_col_addr = (spd->addressing & 0x7) + 9;
170 	pdimm->n_banks_per_sdram_device = 8 << ((spd->density_banks >> 4) & 0x7);
171 
172 	/*
173 	 * The SPD spec has not the ECC bit,
174 	 * We consider the DIMM as ECC capability
175 	 * when the extension bus exist
176 	 */
177 	if (pdimm->ec_sdram_width)
178 		pdimm->edc_config = 0x02;
179 	else
180 		pdimm->edc_config = 0x00;
181 
182 	/*
183 	 * The SPD spec has not the burst length byte
184 	 * but DDR3 spec has nature BL8 and BC4,
185 	 * BL8 -bit3, BC4 -bit2
186 	 */
187 	pdimm->burst_lengths_bitmask = 0x0c;
188 
189 	/* MTB - medium timebase
190 	 * The unit in the SPD spec is ns,
191 	 * We convert it to ps.
192 	 * eg: MTB = 0.125ns (125ps)
193 	 */
194 	mtb_ps = (spd->mtb_dividend * 1000) /spd->mtb_divisor;
195 	pdimm->mtb_ps = mtb_ps;
196 
197 	/*
198 	 * FTB - fine timebase
199 	 * use 1/10th of ps as our unit to avoid floating point
200 	 * eg, 10 for 1ps, 25 for 2.5ps, 50 for 5ps
201 	 */
202 	ftb_10th_ps =
203 		((spd->ftb_div & 0xf0) >> 4) * 10 / (spd->ftb_div & 0x0f);
204 	pdimm->ftb_10th_ps = ftb_10th_ps;
205 	/*
206 	 * sdram minimum cycle time
207 	 * we assume the MTB is 0.125ns
208 	 * eg:
209 	 * tck_min=15 MTB (1.875ns) ->DDR3-1066
210 	 *        =12 MTB (1.5ns) ->DDR3-1333
211 	 *        =10 MTB (1.25ns) ->DDR3-1600
212 	 */
213 	pdimm->tckmin_x_ps = spd->tck_min * mtb_ps +
214 		(spd->fine_tck_min * ftb_10th_ps) / 10;
215 
216 	/*
217 	 * CAS latency supported
218 	 * bit4 - CL4
219 	 * bit5 - CL5
220 	 * bit18 - CL18
221 	 */
222 	pdimm->caslat_x  = ((spd->caslat_msb << 8) | spd->caslat_lsb) << 4;
223 
224 	/*
225 	 * min CAS latency time
226 	 * eg: taa_min =
227 	 * DDR3-800D	100 MTB (12.5ns)
228 	 * DDR3-1066F	105 MTB (13.125ns)
229 	 * DDR3-1333H	108 MTB (13.5ns)
230 	 * DDR3-1600H	90 MTB (11.25ns)
231 	 */
232 	pdimm->taa_ps = spd->taa_min * mtb_ps +
233 		(spd->fine_taa_min * ftb_10th_ps) / 10;
234 
235 	/*
236 	 * min write recovery time
237 	 * eg:
238 	 * twr_min = 120 MTB (15ns) -> all speed grades.
239 	 */
240 	pdimm->twr_ps = spd->twr_min * mtb_ps;
241 
242 	/*
243 	 * min RAS to CAS delay time
244 	 * eg: trcd_min =
245 	 * DDR3-800	100 MTB (12.5ns)
246 	 * DDR3-1066F	105 MTB (13.125ns)
247 	 * DDR3-1333H	108 MTB (13.5ns)
248 	 * DDR3-1600H	90 MTB (11.25)
249 	 */
250 	pdimm->trcd_ps = spd->trcd_min * mtb_ps +
251 		(spd->fine_trcd_min * ftb_10th_ps) / 10;
252 
253 	/*
254 	 * min row active to row active delay time
255 	 * eg: trrd_min =
256 	 * DDR3-800(1KB page)	80 MTB (10ns)
257 	 * DDR3-1333(1KB page)	48 MTB (6ns)
258 	 */
259 	pdimm->trrd_ps = spd->trrd_min * mtb_ps;
260 
261 	/*
262 	 * min row precharge delay time
263 	 * eg: trp_min =
264 	 * DDR3-800D	100 MTB (12.5ns)
265 	 * DDR3-1066F	105 MTB (13.125ns)
266 	 * DDR3-1333H	108 MTB (13.5ns)
267 	 * DDR3-1600H	90 MTB (11.25ns)
268 	 */
269 	pdimm->trp_ps = spd->trp_min * mtb_ps +
270 		(spd->fine_trp_min * ftb_10th_ps) / 10;
271 
272 	/* min active to precharge delay time
273 	 * eg: tRAS_min =
274 	 * DDR3-800D	300 MTB (37.5ns)
275 	 * DDR3-1066F	300 MTB (37.5ns)
276 	 * DDR3-1333H	288 MTB (36ns)
277 	 * DDR3-1600H	280 MTB (35ns)
278 	 */
279 	pdimm->tras_ps = (((spd->tras_trc_ext & 0xf) << 8) | spd->tras_min_lsb)
280 			* mtb_ps;
281 	/*
282 	 * min active to actice/refresh delay time
283 	 * eg: tRC_min =
284 	 * DDR3-800D	400 MTB (50ns)
285 	 * DDR3-1066F	405 MTB (50.625ns)
286 	 * DDR3-1333H	396 MTB (49.5ns)
287 	 * DDR3-1600H	370 MTB (46.25ns)
288 	 */
289 	pdimm->trc_ps = (((spd->tras_trc_ext & 0xf0) << 4) | spd->trc_min_lsb)
290 			* mtb_ps + (spd->fine_trc_min * ftb_10th_ps) / 10;
291 	/*
292 	 * min refresh recovery delay time
293 	 * eg: tRFC_min =
294 	 * 512Mb	720 MTB (90ns)
295 	 * 1Gb		880 MTB (110ns)
296 	 * 2Gb		1280 MTB (160ns)
297 	 */
298 	pdimm->trfc_ps = ((spd->trfc_min_msb << 8) | spd->trfc_min_lsb)
299 			* mtb_ps;
300 	/*
301 	 * min internal write to read command delay time
302 	 * eg: twtr_min = 40 MTB (7.5ns) - all speed bins.
303 	 * tWRT is at least 4 mclk independent of operating freq.
304 	 */
305 	pdimm->twtr_ps = spd->twtr_min * mtb_ps;
306 
307 	/*
308 	 * min internal read to precharge command delay time
309 	 * eg: trtp_min = 40 MTB (7.5ns) - all speed bins.
310 	 * tRTP is at least 4 mclk independent of operating freq.
311 	 */
312 	pdimm->trtp_ps = spd->trtp_min * mtb_ps;
313 
314 	/*
315 	 * Average periodic refresh interval
316 	 * tREFI = 7.8 us at normal temperature range
317 	 *       = 3.9 us at ext temperature range
318 	 */
319 	pdimm->refresh_rate_ps = 7800000;
320 	if ((spd->therm_ref_opt & 0x1) && !(spd->therm_ref_opt & 0x2)) {
321 		pdimm->refresh_rate_ps = 3900000;
322 		pdimm->extended_op_srt = 1;
323 	}
324 
325 	/*
326 	 * min four active window delay time
327 	 * eg: tfaw_min =
328 	 * DDR3-800(1KB page)	320 MTB (40ns)
329 	 * DDR3-1066(1KB page)	300 MTB (37.5ns)
330 	 * DDR3-1333(1KB page)	240 MTB (30ns)
331 	 * DDR3-1600(1KB page)	240 MTB (30ns)
332 	 */
333 	pdimm->tfaw_ps = (((spd->tfaw_msb & 0xf) << 8) | spd->tfaw_min)
334 			* mtb_ps;
335 
336 	return 0;
337 }
338