xref: /openbmc/u-boot/drivers/ddr/fsl/main.c (revision 2399e401)
1 /*
2  * Copyright 2008-2014 Freescale Semiconductor, Inc.
3  *
4  * SPDX-License-Identifier:	GPL-2.0
5  */
6 
7 /*
8  * Generic driver for Freescale DDR/DDR2/DDR3 memory controller.
9  * Based on code from spd_sdram.c
10  * Author: James Yang [at freescale.com]
11  */
12 
13 #include <common.h>
14 #include <i2c.h>
15 #include <fsl_ddr_sdram.h>
16 #include <fsl_ddr.h>
17 
18 /*
19  * CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY is the physical address from the view
20  * of DDR controllers. It is the same as CONFIG_SYS_DDR_SDRAM_BASE for
21  * all Power SoCs. But it could be different for ARM SoCs. For example,
22  * fsl_lsch3 has a mapping mechanism to map DDR memory to ranges (in order) of
23  * 0x00_8000_0000 ~ 0x00_ffff_ffff
24  * 0x80_8000_0000 ~ 0xff_ffff_ffff
25  */
26 #ifndef CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
27 #define CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY CONFIG_SYS_DDR_SDRAM_BASE
28 #endif
29 
30 #ifdef CONFIG_PPC
31 #include <asm/fsl_law.h>
32 
33 void fsl_ddr_set_lawbar(
34 		const common_timing_params_t *memctl_common_params,
35 		unsigned int memctl_interleaved,
36 		unsigned int ctrl_num);
37 #endif
38 
39 void fsl_ddr_set_intl3r(const unsigned int granule_size);
40 #if defined(SPD_EEPROM_ADDRESS) || \
41     defined(SPD_EEPROM_ADDRESS1) || defined(SPD_EEPROM_ADDRESS2) || \
42     defined(SPD_EEPROM_ADDRESS3) || defined(SPD_EEPROM_ADDRESS4)
43 #if (CONFIG_SYS_NUM_DDR_CTLRS == 1) && (CONFIG_DIMM_SLOTS_PER_CTLR == 1)
44 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
45 	[0][0] = SPD_EEPROM_ADDRESS,
46 };
47 #elif (CONFIG_SYS_NUM_DDR_CTLRS == 1) && (CONFIG_DIMM_SLOTS_PER_CTLR == 2)
48 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
49 	[0][0] = SPD_EEPROM_ADDRESS1,	/* controller 1 */
50 	[0][1] = SPD_EEPROM_ADDRESS2,	/* controller 1 */
51 };
52 #elif (CONFIG_SYS_NUM_DDR_CTLRS == 2) && (CONFIG_DIMM_SLOTS_PER_CTLR == 1)
53 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
54 	[0][0] = SPD_EEPROM_ADDRESS1,	/* controller 1 */
55 	[1][0] = SPD_EEPROM_ADDRESS2,	/* controller 2 */
56 };
57 #elif (CONFIG_SYS_NUM_DDR_CTLRS == 2) && (CONFIG_DIMM_SLOTS_PER_CTLR == 2)
58 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
59 	[0][0] = SPD_EEPROM_ADDRESS1,	/* controller 1 */
60 	[0][1] = SPD_EEPROM_ADDRESS2,	/* controller 1 */
61 	[1][0] = SPD_EEPROM_ADDRESS3,	/* controller 2 */
62 	[1][1] = SPD_EEPROM_ADDRESS4,	/* controller 2 */
63 };
64 #elif (CONFIG_SYS_NUM_DDR_CTLRS == 3) && (CONFIG_DIMM_SLOTS_PER_CTLR == 1)
65 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
66 	[0][0] = SPD_EEPROM_ADDRESS1,	/* controller 1 */
67 	[1][0] = SPD_EEPROM_ADDRESS2,	/* controller 2 */
68 	[2][0] = SPD_EEPROM_ADDRESS3,	/* controller 3 */
69 };
70 #elif (CONFIG_SYS_NUM_DDR_CTLRS == 3) && (CONFIG_DIMM_SLOTS_PER_CTLR == 2)
71 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
72 	[0][0] = SPD_EEPROM_ADDRESS1,	/* controller 1 */
73 	[0][1] = SPD_EEPROM_ADDRESS2,	/* controller 1 */
74 	[1][0] = SPD_EEPROM_ADDRESS3,	/* controller 2 */
75 	[1][1] = SPD_EEPROM_ADDRESS4,	/* controller 2 */
76 	[2][0] = SPD_EEPROM_ADDRESS5,	/* controller 3 */
77 	[2][1] = SPD_EEPROM_ADDRESS6,	/* controller 3 */
78 };
79 
80 #endif
81 
82 #define SPD_SPA0_ADDRESS	0x36
83 #define SPD_SPA1_ADDRESS	0x37
84 
85 static void __get_spd(generic_spd_eeprom_t *spd, u8 i2c_address)
86 {
87 	int ret;
88 #ifdef CONFIG_SYS_FSL_DDR4
89 	uint8_t dummy = 0;
90 #endif
91 
92 	i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM);
93 
94 #ifdef CONFIG_SYS_FSL_DDR4
95 	/*
96 	 * DDR4 SPD has 384 to 512 bytes
97 	 * To access the lower 256 bytes, we need to set EE page address to 0
98 	 * To access the upper 256 bytes, we need to set EE page address to 1
99 	 * See Jedec standar No. 21-C for detail
100 	 */
101 	i2c_write(SPD_SPA0_ADDRESS, 0, 1, &dummy, 1);
102 	ret = i2c_read(i2c_address, 0, 1, (uchar *)spd, 256);
103 	if (!ret) {
104 		i2c_write(SPD_SPA1_ADDRESS, 0, 1, &dummy, 1);
105 		ret = i2c_read(i2c_address, 0, 1,
106 			       (uchar *)((ulong)spd + 256),
107 			       min(256,
108 				   (int)sizeof(generic_spd_eeprom_t) - 256));
109 	}
110 #else
111 	ret = i2c_read(i2c_address, 0, 1, (uchar *)spd,
112 				sizeof(generic_spd_eeprom_t));
113 #endif
114 
115 	if (ret) {
116 		if (i2c_address ==
117 #ifdef SPD_EEPROM_ADDRESS
118 				SPD_EEPROM_ADDRESS
119 #elif defined(SPD_EEPROM_ADDRESS1)
120 				SPD_EEPROM_ADDRESS1
121 #endif
122 				) {
123 			printf("DDR: failed to read SPD from address %u\n",
124 				i2c_address);
125 		} else {
126 			debug("DDR: failed to read SPD from address %u\n",
127 				i2c_address);
128 		}
129 		memset(spd, 0, sizeof(generic_spd_eeprom_t));
130 	}
131 }
132 
133 __attribute__((weak, alias("__get_spd")))
134 void get_spd(generic_spd_eeprom_t *spd, u8 i2c_address);
135 
136 /* This function allows boards to update SPD address */
137 __weak void update_spd_address(unsigned int ctrl_num,
138 			       unsigned int slot,
139 			       unsigned int *addr)
140 {
141 }
142 
143 void fsl_ddr_get_spd(generic_spd_eeprom_t *ctrl_dimms_spd,
144 		      unsigned int ctrl_num, unsigned int dimm_slots_per_ctrl)
145 {
146 	unsigned int i;
147 	unsigned int i2c_address = 0;
148 
149 	if (ctrl_num >= CONFIG_SYS_NUM_DDR_CTLRS) {
150 		printf("%s unexpected ctrl_num = %u\n", __FUNCTION__, ctrl_num);
151 		return;
152 	}
153 
154 	for (i = 0; i < dimm_slots_per_ctrl; i++) {
155 		i2c_address = spd_i2c_addr[ctrl_num][i];
156 		update_spd_address(ctrl_num, i, &i2c_address);
157 		get_spd(&(ctrl_dimms_spd[i]), i2c_address);
158 	}
159 }
160 #else
161 void fsl_ddr_get_spd(generic_spd_eeprom_t *ctrl_dimms_spd,
162 		      unsigned int ctrl_num, unsigned int dimm_slots_per_ctrl)
163 {
164 }
165 #endif /* SPD_EEPROM_ADDRESSx */
166 
167 /*
168  * ASSUMPTIONS:
169  *    - Same number of CONFIG_DIMM_SLOTS_PER_CTLR on each controller
170  *    - Same memory data bus width on all controllers
171  *
172  * NOTES:
173  *
174  * The memory controller and associated documentation use confusing
175  * terminology when referring to the orgranization of DRAM.
176  *
177  * Here is a terminology translation table:
178  *
179  * memory controller/documention  |industry   |this code  |signals
180  * -------------------------------|-----------|-----------|-----------------
181  * physical bank/bank		  |rank       |rank	  |chip select (CS)
182  * logical bank/sub-bank	  |bank       |bank	  |bank address (BA)
183  * page/row			  |row	      |page	  |row address
184  * ???				  |column     |column	  |column address
185  *
186  * The naming confusion is further exacerbated by the descriptions of the
187  * memory controller interleaving feature, where accesses are interleaved
188  * _BETWEEN_ two seperate memory controllers.  This is configured only in
189  * CS0_CONFIG[INTLV_CTL] of each memory controller.
190  *
191  * memory controller documentation | number of chip selects
192  *				   | per memory controller supported
193  * --------------------------------|-----------------------------------------
194  * cache line interleaving	   | 1 (CS0 only)
195  * page interleaving		   | 1 (CS0 only)
196  * bank interleaving		   | 1 (CS0 only)
197  * superbank interleraving	   | depends on bank (chip select)
198  *				   |   interleraving [rank interleaving]
199  *				   |   mode used on every memory controller
200  *
201  * Even further confusing is the existence of the interleaving feature
202  * _WITHIN_ each memory controller.  The feature is referred to in
203  * documentation as chip select interleaving or bank interleaving,
204  * although it is configured in the DDR_SDRAM_CFG field.
205  *
206  * Name of field		| documentation name	| this code
207  * -----------------------------|-----------------------|------------------
208  * DDR_SDRAM_CFG[BA_INTLV_CTL]	| Bank (chip select)	| rank interleaving
209  *				|  interleaving
210  */
211 
212 const char *step_string_tbl[] = {
213 	"STEP_GET_SPD",
214 	"STEP_COMPUTE_DIMM_PARMS",
215 	"STEP_COMPUTE_COMMON_PARMS",
216 	"STEP_GATHER_OPTS",
217 	"STEP_ASSIGN_ADDRESSES",
218 	"STEP_COMPUTE_REGS",
219 	"STEP_PROGRAM_REGS",
220 	"STEP_ALL"
221 };
222 
223 const char * step_to_string(unsigned int step) {
224 
225 	unsigned int s = __ilog2(step);
226 
227 	if ((1 << s) != step)
228 		return step_string_tbl[7];
229 
230 	if (s >= ARRAY_SIZE(step_string_tbl)) {
231 		printf("Error for the step in %s\n", __func__);
232 		s = 0;
233 	}
234 
235 	return step_string_tbl[s];
236 }
237 
238 static unsigned long long __step_assign_addresses(fsl_ddr_info_t *pinfo,
239 			  unsigned int dbw_cap_adj[])
240 {
241 	unsigned int i, j;
242 	unsigned long long total_mem, current_mem_base, total_ctlr_mem;
243 	unsigned long long rank_density, ctlr_density = 0;
244 	unsigned int first_ctrl = pinfo->first_ctrl;
245 	unsigned int last_ctrl = first_ctrl + pinfo->num_ctrls - 1;
246 
247 	/*
248 	 * If a reduced data width is requested, but the SPD
249 	 * specifies a physically wider device, adjust the
250 	 * computed dimm capacities accordingly before
251 	 * assigning addresses.
252 	 */
253 	for (i = first_ctrl; i <= last_ctrl; i++) {
254 		unsigned int found = 0;
255 
256 		switch (pinfo->memctl_opts[i].data_bus_width) {
257 		case 2:
258 			/* 16-bit */
259 			for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
260 				unsigned int dw;
261 				if (!pinfo->dimm_params[i][j].n_ranks)
262 					continue;
263 				dw = pinfo->dimm_params[i][j].primary_sdram_width;
264 				if ((dw == 72 || dw == 64)) {
265 					dbw_cap_adj[i] = 2;
266 					break;
267 				} else if ((dw == 40 || dw == 32)) {
268 					dbw_cap_adj[i] = 1;
269 					break;
270 				}
271 			}
272 			break;
273 
274 		case 1:
275 			/* 32-bit */
276 			for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
277 				unsigned int dw;
278 				dw = pinfo->dimm_params[i][j].data_width;
279 				if (pinfo->dimm_params[i][j].n_ranks
280 				    && (dw == 72 || dw == 64)) {
281 					/*
282 					 * FIXME: can't really do it
283 					 * like this because this just
284 					 * further reduces the memory
285 					 */
286 					found = 1;
287 					break;
288 				}
289 			}
290 			if (found) {
291 				dbw_cap_adj[i] = 1;
292 			}
293 			break;
294 
295 		case 0:
296 			/* 64-bit */
297 			break;
298 
299 		default:
300 			printf("unexpected data bus width "
301 				"specified controller %u\n", i);
302 			return 1;
303 		}
304 		debug("dbw_cap_adj[%d]=%d\n", i, dbw_cap_adj[i]);
305 	}
306 
307 	current_mem_base = pinfo->mem_base;
308 	total_mem = 0;
309 	if (pinfo->memctl_opts[first_ctrl].memctl_interleaving) {
310 		rank_density = pinfo->dimm_params[first_ctrl][0].rank_density >>
311 					dbw_cap_adj[first_ctrl];
312 		switch (pinfo->memctl_opts[first_ctrl].ba_intlv_ctl &
313 					FSL_DDR_CS0_CS1_CS2_CS3) {
314 		case FSL_DDR_CS0_CS1_CS2_CS3:
315 			ctlr_density = 4 * rank_density;
316 			break;
317 		case FSL_DDR_CS0_CS1:
318 		case FSL_DDR_CS0_CS1_AND_CS2_CS3:
319 			ctlr_density = 2 * rank_density;
320 			break;
321 		case FSL_DDR_CS2_CS3:
322 		default:
323 			ctlr_density = rank_density;
324 			break;
325 		}
326 		debug("rank density is 0x%llx, ctlr density is 0x%llx\n",
327 			rank_density, ctlr_density);
328 		for (i = first_ctrl; i <= last_ctrl; i++) {
329 			if (pinfo->memctl_opts[i].memctl_interleaving) {
330 				switch (pinfo->memctl_opts[i].memctl_interleaving_mode) {
331 				case FSL_DDR_256B_INTERLEAVING:
332 				case FSL_DDR_CACHE_LINE_INTERLEAVING:
333 				case FSL_DDR_PAGE_INTERLEAVING:
334 				case FSL_DDR_BANK_INTERLEAVING:
335 				case FSL_DDR_SUPERBANK_INTERLEAVING:
336 					total_ctlr_mem = 2 * ctlr_density;
337 					break;
338 				case FSL_DDR_3WAY_1KB_INTERLEAVING:
339 				case FSL_DDR_3WAY_4KB_INTERLEAVING:
340 				case FSL_DDR_3WAY_8KB_INTERLEAVING:
341 					total_ctlr_mem = 3 * ctlr_density;
342 					break;
343 				case FSL_DDR_4WAY_1KB_INTERLEAVING:
344 				case FSL_DDR_4WAY_4KB_INTERLEAVING:
345 				case FSL_DDR_4WAY_8KB_INTERLEAVING:
346 					total_ctlr_mem = 4 * ctlr_density;
347 					break;
348 				default:
349 					panic("Unknown interleaving mode");
350 				}
351 				pinfo->common_timing_params[i].base_address =
352 							current_mem_base;
353 				pinfo->common_timing_params[i].total_mem =
354 							total_ctlr_mem;
355 				total_mem = current_mem_base + total_ctlr_mem;
356 				debug("ctrl %d base 0x%llx\n", i, current_mem_base);
357 				debug("ctrl %d total 0x%llx\n", i, total_ctlr_mem);
358 			} else {
359 				/* when 3rd controller not interleaved */
360 				current_mem_base = total_mem;
361 				total_ctlr_mem = 0;
362 				pinfo->common_timing_params[i].base_address =
363 							current_mem_base;
364 				for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
365 					unsigned long long cap =
366 						pinfo->dimm_params[i][j].capacity >> dbw_cap_adj[i];
367 					pinfo->dimm_params[i][j].base_address =
368 						current_mem_base;
369 					debug("ctrl %d dimm %d base 0x%llx\n", i, j, current_mem_base);
370 					current_mem_base += cap;
371 					total_ctlr_mem += cap;
372 				}
373 				debug("ctrl %d total 0x%llx\n", i, total_ctlr_mem);
374 				pinfo->common_timing_params[i].total_mem =
375 							total_ctlr_mem;
376 				total_mem += total_ctlr_mem;
377 			}
378 		}
379 	} else {
380 		/*
381 		 * Simple linear assignment if memory
382 		 * controllers are not interleaved.
383 		 */
384 		for (i = first_ctrl; i <= last_ctrl; i++) {
385 			total_ctlr_mem = 0;
386 			pinfo->common_timing_params[i].base_address =
387 						current_mem_base;
388 			for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
389 				/* Compute DIMM base addresses. */
390 				unsigned long long cap =
391 					pinfo->dimm_params[i][j].capacity >> dbw_cap_adj[i];
392 				pinfo->dimm_params[i][j].base_address =
393 					current_mem_base;
394 				debug("ctrl %d dimm %d base 0x%llx\n", i, j, current_mem_base);
395 				current_mem_base += cap;
396 				total_ctlr_mem += cap;
397 			}
398 			debug("ctrl %d total 0x%llx\n", i, total_ctlr_mem);
399 			pinfo->common_timing_params[i].total_mem =
400 							total_ctlr_mem;
401 			total_mem += total_ctlr_mem;
402 		}
403 	}
404 	debug("Total mem by %s is 0x%llx\n", __func__, total_mem);
405 
406 	return total_mem;
407 }
408 
409 /* Use weak function to allow board file to override the address assignment */
410 __attribute__((weak, alias("__step_assign_addresses")))
411 unsigned long long step_assign_addresses(fsl_ddr_info_t *pinfo,
412 			  unsigned int dbw_cap_adj[]);
413 
414 unsigned long long
415 fsl_ddr_compute(fsl_ddr_info_t *pinfo, unsigned int start_step,
416 				       unsigned int size_only)
417 {
418 	unsigned int i, j;
419 	unsigned long long total_mem = 0;
420 	int assert_reset = 0;
421 	unsigned int first_ctrl =  pinfo->first_ctrl;
422 	unsigned int last_ctrl = first_ctrl + pinfo->num_ctrls - 1;
423 	__maybe_unused int retval;
424 	__maybe_unused bool goodspd = false;
425 	__maybe_unused int dimm_slots_per_ctrl = pinfo->dimm_slots_per_ctrl;
426 
427 	fsl_ddr_cfg_regs_t *ddr_reg = pinfo->fsl_ddr_config_reg;
428 	common_timing_params_t *timing_params = pinfo->common_timing_params;
429 	if (pinfo->board_need_mem_reset)
430 		assert_reset = pinfo->board_need_mem_reset();
431 
432 	/* data bus width capacity adjust shift amount */
433 	unsigned int dbw_capacity_adjust[CONFIG_SYS_NUM_DDR_CTLRS];
434 
435 	for (i = first_ctrl; i <= last_ctrl; i++)
436 		dbw_capacity_adjust[i] = 0;
437 
438 	debug("starting at step %u (%s)\n",
439 	      start_step, step_to_string(start_step));
440 
441 	switch (start_step) {
442 	case STEP_GET_SPD:
443 #if defined(CONFIG_DDR_SPD) || defined(CONFIG_SPD_EEPROM)
444 		/* STEP 1:  Gather all DIMM SPD data */
445 		for (i = first_ctrl; i <= last_ctrl; i++) {
446 			fsl_ddr_get_spd(pinfo->spd_installed_dimms[i], i,
447 					dimm_slots_per_ctrl);
448 		}
449 
450 	case STEP_COMPUTE_DIMM_PARMS:
451 		/* STEP 2:  Compute DIMM parameters from SPD data */
452 
453 		for (i = first_ctrl; i <= last_ctrl; i++) {
454 			for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
455 				generic_spd_eeprom_t *spd =
456 					&(pinfo->spd_installed_dimms[i][j]);
457 				dimm_params_t *pdimm =
458 					&(pinfo->dimm_params[i][j]);
459 				retval = compute_dimm_parameters(
460 							i, spd, pdimm, j);
461 #ifdef CONFIG_SYS_DDR_RAW_TIMING
462 				if (!j && retval) {
463 					printf("SPD error on controller %d! "
464 					"Trying fallback to raw timing "
465 					"calculation\n", i);
466 					retval = fsl_ddr_get_dimm_params(pdimm,
467 									 i, j);
468 				}
469 #else
470 				if (retval == 2) {
471 					printf("Error: compute_dimm_parameters"
472 					" non-zero returned FATAL value "
473 					"for memctl=%u dimm=%u\n", i, j);
474 					return 0;
475 				}
476 #endif
477 				if (retval) {
478 					debug("Warning: compute_dimm_parameters"
479 					" non-zero return value for memctl=%u "
480 					"dimm=%u\n", i, j);
481 				} else {
482 					goodspd = true;
483 				}
484 			}
485 		}
486 		if (!goodspd) {
487 			/*
488 			 * No valid SPD found
489 			 * Throw an error if this is for main memory, i.e.
490 			 * first_ctrl == 0. Otherwise, siliently return 0
491 			 * as the memory size.
492 			 */
493 			if (first_ctrl == 0)
494 				printf("Error: No valid SPD detected.\n");
495 
496 			return 0;
497 		}
498 #elif defined(CONFIG_SYS_DDR_RAW_TIMING)
499 	case STEP_COMPUTE_DIMM_PARMS:
500 		for (i = first_ctrl; i <= last_ctrl; i++) {
501 			for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
502 				dimm_params_t *pdimm =
503 					&(pinfo->dimm_params[i][j]);
504 				fsl_ddr_get_dimm_params(pdimm, i, j);
505 			}
506 		}
507 		debug("Filling dimm parameters from board specific file\n");
508 #endif
509 	case STEP_COMPUTE_COMMON_PARMS:
510 		/*
511 		 * STEP 3: Compute a common set of timing parameters
512 		 * suitable for all of the DIMMs on each memory controller
513 		 */
514 		for (i = first_ctrl; i <= last_ctrl; i++) {
515 			debug("Computing lowest common DIMM"
516 				" parameters for memctl=%u\n", i);
517 			compute_lowest_common_dimm_parameters
518 				(i,
519 				 pinfo->dimm_params[i],
520 				 &timing_params[i],
521 				 CONFIG_DIMM_SLOTS_PER_CTLR);
522 		}
523 
524 	case STEP_GATHER_OPTS:
525 		/* STEP 4:  Gather configuration requirements from user */
526 		for (i = first_ctrl; i <= last_ctrl; i++) {
527 			debug("Reloading memory controller "
528 				"configuration options for memctl=%u\n", i);
529 			/*
530 			 * This "reloads" the memory controller options
531 			 * to defaults.  If the user "edits" an option,
532 			 * next_step points to the step after this,
533 			 * which is currently STEP_ASSIGN_ADDRESSES.
534 			 */
535 			populate_memctl_options(
536 					&timing_params[i],
537 					&pinfo->memctl_opts[i],
538 					pinfo->dimm_params[i], i);
539 			/*
540 			 * For RDIMMs, JEDEC spec requires clocks to be stable
541 			 * before reset signal is deasserted. For the boards
542 			 * using fixed parameters, this function should be
543 			 * be called from board init file.
544 			 */
545 			if (timing_params[i].all_dimms_registered)
546 				assert_reset = 1;
547 		}
548 		if (assert_reset && !size_only) {
549 			if (pinfo->board_mem_reset) {
550 				debug("Asserting mem reset\n");
551 				pinfo->board_mem_reset();
552 			} else {
553 				debug("Asserting mem reset missing\n");
554 			}
555 		}
556 
557 	case STEP_ASSIGN_ADDRESSES:
558 		/* STEP 5:  Assign addresses to chip selects */
559 		check_interleaving_options(pinfo);
560 		total_mem = step_assign_addresses(pinfo, dbw_capacity_adjust);
561 		debug("Total mem %llu assigned\n", total_mem);
562 
563 	case STEP_COMPUTE_REGS:
564 		/* STEP 6:  compute controller register values */
565 		debug("FSL Memory ctrl register computation\n");
566 		for (i = first_ctrl; i <= last_ctrl; i++) {
567 			if (timing_params[i].ndimms_present == 0) {
568 				memset(&ddr_reg[i], 0,
569 					sizeof(fsl_ddr_cfg_regs_t));
570 				continue;
571 			}
572 
573 			compute_fsl_memctl_config_regs
574 				(i,
575 				 &pinfo->memctl_opts[i],
576 				 &ddr_reg[i], &timing_params[i],
577 				 pinfo->dimm_params[i],
578 				 dbw_capacity_adjust[i],
579 				 size_only);
580 		}
581 
582 	default:
583 		break;
584 	}
585 
586 	{
587 		/*
588 		 * Compute the amount of memory available just by
589 		 * looking for the highest valid CSn_BNDS value.
590 		 * This allows us to also experiment with using
591 		 * only CS0 when using dual-rank DIMMs.
592 		 */
593 		unsigned int max_end = 0;
594 
595 		for (i = first_ctrl; i <= last_ctrl; i++) {
596 			for (j = 0; j < CONFIG_CHIP_SELECTS_PER_CTRL; j++) {
597 				fsl_ddr_cfg_regs_t *reg = &ddr_reg[i];
598 				if (reg->cs[j].config & 0x80000000) {
599 					unsigned int end;
600 					/*
601 					 * 0xfffffff is a special value we put
602 					 * for unused bnds
603 					 */
604 					if (reg->cs[j].bnds == 0xffffffff)
605 						continue;
606 					end = reg->cs[j].bnds & 0xffff;
607 					if (end > max_end) {
608 						max_end = end;
609 					}
610 				}
611 			}
612 		}
613 
614 		total_mem = 1 + (((unsigned long long)max_end << 24ULL) |
615 			    0xFFFFFFULL) - pinfo->mem_base;
616 	}
617 
618 	return total_mem;
619 }
620 
621 phys_size_t __fsl_ddr_sdram(fsl_ddr_info_t *pinfo)
622 {
623 	unsigned int i, first_ctrl, last_ctrl;
624 #ifdef CONFIG_PPC
625 	unsigned int law_memctl = LAW_TRGT_IF_DDR_1;
626 #endif
627 	unsigned long long total_memory;
628 	int deassert_reset = 0;
629 
630 	first_ctrl = pinfo->first_ctrl;
631 	last_ctrl = first_ctrl + pinfo->num_ctrls - 1;
632 
633 	/* Compute it once normally. */
634 #ifdef CONFIG_FSL_DDR_INTERACTIVE
635 	if (tstc() && (getc() == 'd')) {	/* we got a key press of 'd' */
636 		total_memory = fsl_ddr_interactive(pinfo, 0);
637 	} else if (fsl_ddr_interactive_env_var_exists()) {
638 		total_memory = fsl_ddr_interactive(pinfo, 1);
639 	} else
640 #endif
641 		total_memory = fsl_ddr_compute(pinfo, STEP_GET_SPD, 0);
642 
643 	/* setup 3-way interleaving before enabling DDRC */
644 	switch (pinfo->memctl_opts[first_ctrl].memctl_interleaving_mode) {
645 	case FSL_DDR_3WAY_1KB_INTERLEAVING:
646 	case FSL_DDR_3WAY_4KB_INTERLEAVING:
647 	case FSL_DDR_3WAY_8KB_INTERLEAVING:
648 		fsl_ddr_set_intl3r(
649 			pinfo->memctl_opts[first_ctrl].
650 			memctl_interleaving_mode);
651 		break;
652 	default:
653 		break;
654 	}
655 
656 	/*
657 	 * Program configuration registers.
658 	 * JEDEC specs requires clocks to be stable before deasserting reset
659 	 * for RDIMMs. Clocks start after chip select is enabled and clock
660 	 * control register is set. During step 1, all controllers have their
661 	 * registers set but not enabled. Step 2 proceeds after deasserting
662 	 * reset through board FPGA or GPIO.
663 	 * For non-registered DIMMs, initialization can go through but it is
664 	 * also OK to follow the same flow.
665 	 */
666 	if (pinfo->board_need_mem_reset)
667 		deassert_reset = pinfo->board_need_mem_reset();
668 	for (i = first_ctrl; i <= last_ctrl; i++) {
669 		if (pinfo->common_timing_params[i].all_dimms_registered)
670 			deassert_reset = 1;
671 	}
672 	for (i = first_ctrl; i <= last_ctrl; i++) {
673 		debug("Programming controller %u\n", i);
674 		if (pinfo->common_timing_params[i].ndimms_present == 0) {
675 			debug("No dimms present on controller %u; "
676 					"skipping programming\n", i);
677 			continue;
678 		}
679 		/*
680 		 * The following call with step = 1 returns before enabling
681 		 * the controller. It has to finish with step = 2 later.
682 		 */
683 		fsl_ddr_set_memctl_regs(&(pinfo->fsl_ddr_config_reg[i]), i,
684 					deassert_reset ? 1 : 0);
685 	}
686 	if (deassert_reset) {
687 		/* Use board FPGA or GPIO to deassert reset signal */
688 		if (pinfo->board_mem_de_reset) {
689 			debug("Deasserting mem reset\n");
690 			pinfo->board_mem_de_reset();
691 		} else {
692 			debug("Deasserting mem reset missing\n");
693 		}
694 		for (i = first_ctrl; i <= last_ctrl; i++) {
695 			/* Call with step = 2 to continue initialization */
696 			fsl_ddr_set_memctl_regs(&(pinfo->fsl_ddr_config_reg[i]),
697 						i, 2);
698 		}
699 	}
700 
701 #ifdef CONFIG_FSL_DDR_SYNC_REFRESH
702 	fsl_ddr_sync_memctl_refresh(first_ctrl, last_ctrl);
703 #endif
704 
705 #ifdef CONFIG_PPC
706 	/* program LAWs */
707 	for (i = first_ctrl; i <= last_ctrl; i++) {
708 		if (pinfo->memctl_opts[i].memctl_interleaving) {
709 			switch (pinfo->memctl_opts[i].
710 				memctl_interleaving_mode) {
711 			case FSL_DDR_CACHE_LINE_INTERLEAVING:
712 			case FSL_DDR_PAGE_INTERLEAVING:
713 			case FSL_DDR_BANK_INTERLEAVING:
714 			case FSL_DDR_SUPERBANK_INTERLEAVING:
715 				if (i % 2)
716 					break;
717 				if (i == 0) {
718 					law_memctl = LAW_TRGT_IF_DDR_INTRLV;
719 					fsl_ddr_set_lawbar(
720 						&pinfo->common_timing_params[i],
721 						law_memctl, i);
722 				}
723 #if CONFIG_SYS_NUM_DDR_CTLRS > 3
724 				else if (i == 2) {
725 					law_memctl = LAW_TRGT_IF_DDR_INTLV_34;
726 					fsl_ddr_set_lawbar(
727 						&pinfo->common_timing_params[i],
728 						law_memctl, i);
729 				}
730 #endif
731 				break;
732 			case FSL_DDR_3WAY_1KB_INTERLEAVING:
733 			case FSL_DDR_3WAY_4KB_INTERLEAVING:
734 			case FSL_DDR_3WAY_8KB_INTERLEAVING:
735 				law_memctl = LAW_TRGT_IF_DDR_INTLV_123;
736 				if (i == 0) {
737 					fsl_ddr_set_lawbar(
738 						&pinfo->common_timing_params[i],
739 						law_memctl, i);
740 				}
741 				break;
742 			case FSL_DDR_4WAY_1KB_INTERLEAVING:
743 			case FSL_DDR_4WAY_4KB_INTERLEAVING:
744 			case FSL_DDR_4WAY_8KB_INTERLEAVING:
745 				law_memctl = LAW_TRGT_IF_DDR_INTLV_1234;
746 				if (i == 0)
747 					fsl_ddr_set_lawbar(
748 						&pinfo->common_timing_params[i],
749 						law_memctl, i);
750 				/* place holder for future 4-way interleaving */
751 				break;
752 			default:
753 				break;
754 			}
755 		} else {
756 			switch (i) {
757 			case 0:
758 				law_memctl = LAW_TRGT_IF_DDR_1;
759 				break;
760 			case 1:
761 				law_memctl = LAW_TRGT_IF_DDR_2;
762 				break;
763 			case 2:
764 				law_memctl = LAW_TRGT_IF_DDR_3;
765 				break;
766 			case 3:
767 				law_memctl = LAW_TRGT_IF_DDR_4;
768 				break;
769 			default:
770 				break;
771 			}
772 			fsl_ddr_set_lawbar(&pinfo->common_timing_params[i],
773 					   law_memctl, i);
774 		}
775 	}
776 #endif
777 
778 	debug("total_memory by %s = %llu\n", __func__, total_memory);
779 
780 #if !defined(CONFIG_PHYS_64BIT)
781 	/* Check for 4G or more.  Bad. */
782 	if ((first_ctrl == 0) && (total_memory >= (1ull << 32))) {
783 		puts("Detected ");
784 		print_size(total_memory, " of memory\n");
785 		printf("       This U-Boot only supports < 4G of DDR\n");
786 		printf("       You could rebuild it with CONFIG_PHYS_64BIT\n");
787 		printf("       "); /* re-align to match init_func_ram print */
788 		total_memory = CONFIG_MAX_MEM_MAPPED;
789 	}
790 #endif
791 
792 	return total_memory;
793 }
794 
795 /*
796  * fsl_ddr_sdram(void) -- this is the main function to be
797  * called by initdram() in the board file.
798  *
799  * It returns amount of memory configured in bytes.
800  */
801 phys_size_t fsl_ddr_sdram(void)
802 {
803 	fsl_ddr_info_t info;
804 
805 	/* Reset info structure. */
806 	memset(&info, 0, sizeof(fsl_ddr_info_t));
807 	info.mem_base = CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY;
808 	info.first_ctrl = 0;
809 	info.num_ctrls = CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS;
810 	info.dimm_slots_per_ctrl = CONFIG_DIMM_SLOTS_PER_CTLR;
811 	info.board_need_mem_reset = board_need_mem_reset;
812 	info.board_mem_reset = board_assert_mem_reset;
813 	info.board_mem_de_reset = board_deassert_mem_reset;
814 	remove_unused_controllers(&info);
815 
816 	return __fsl_ddr_sdram(&info);
817 }
818 
819 #ifdef CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
820 phys_size_t fsl_other_ddr_sdram(unsigned long long base,
821 				unsigned int first_ctrl,
822 				unsigned int num_ctrls,
823 				unsigned int dimm_slots_per_ctrl,
824 				int (*board_need_reset)(void),
825 				void (*board_reset)(void),
826 				void (*board_de_reset)(void))
827 {
828 	fsl_ddr_info_t info;
829 
830 	/* Reset info structure. */
831 	memset(&info, 0, sizeof(fsl_ddr_info_t));
832 	info.mem_base = base;
833 	info.first_ctrl = first_ctrl;
834 	info.num_ctrls = num_ctrls;
835 	info.dimm_slots_per_ctrl = dimm_slots_per_ctrl;
836 	info.board_need_mem_reset = board_need_reset;
837 	info.board_mem_reset = board_reset;
838 	info.board_mem_de_reset = board_de_reset;
839 
840 	return __fsl_ddr_sdram(&info);
841 }
842 #endif
843 
844 /*
845  * fsl_ddr_sdram_size(first_ctrl, last_intlv) - This function only returns the
846  * size of the total memory without setting ddr control registers.
847  */
848 phys_size_t
849 fsl_ddr_sdram_size(void)
850 {
851 	fsl_ddr_info_t  info;
852 	unsigned long long total_memory = 0;
853 
854 	memset(&info, 0 , sizeof(fsl_ddr_info_t));
855 	info.mem_base = CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY;
856 	info.first_ctrl = 0;
857 	info.num_ctrls = CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS;
858 	info.dimm_slots_per_ctrl = CONFIG_DIMM_SLOTS_PER_CTLR;
859 	info.board_need_mem_reset = NULL;
860 	remove_unused_controllers(&info);
861 
862 	/* Compute it once normally. */
863 	total_memory = fsl_ddr_compute(&info, STEP_GET_SPD, 1);
864 
865 	return total_memory;
866 }
867