xref: /openbmc/u-boot/drivers/ddr/fsl/main.c (revision 8ee59472)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright 2008-2014 Freescale Semiconductor, Inc.
4  */
5 
6 /*
7  * Generic driver for Freescale DDR/DDR2/DDR3 memory controller.
8  * Based on code from spd_sdram.c
9  * Author: James Yang [at freescale.com]
10  */
11 
12 #include <common.h>
13 #include <i2c.h>
14 #include <fsl_ddr_sdram.h>
15 #include <fsl_ddr.h>
16 
17 /*
18  * CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY is the physical address from the view
19  * of DDR controllers. It is the same as CONFIG_SYS_DDR_SDRAM_BASE for
20  * all Power SoCs. But it could be different for ARM SoCs. For example,
21  * fsl_lsch3 has a mapping mechanism to map DDR memory to ranges (in order) of
22  * 0x00_8000_0000 ~ 0x00_ffff_ffff
23  * 0x80_8000_0000 ~ 0xff_ffff_ffff
24  */
25 #ifndef CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
26 #define CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY CONFIG_SYS_DDR_SDRAM_BASE
27 #endif
28 
29 #ifdef CONFIG_PPC
30 #include <asm/fsl_law.h>
31 
32 void fsl_ddr_set_lawbar(
33 		const common_timing_params_t *memctl_common_params,
34 		unsigned int memctl_interleaved,
35 		unsigned int ctrl_num);
36 #endif
37 
38 void fsl_ddr_set_intl3r(const unsigned int granule_size);
39 #if defined(SPD_EEPROM_ADDRESS) || \
40     defined(SPD_EEPROM_ADDRESS1) || defined(SPD_EEPROM_ADDRESS2) || \
41     defined(SPD_EEPROM_ADDRESS3) || defined(SPD_EEPROM_ADDRESS4)
42 #if (CONFIG_SYS_NUM_DDR_CTLRS == 1) && (CONFIG_DIMM_SLOTS_PER_CTLR == 1)
43 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
44 	[0][0] = SPD_EEPROM_ADDRESS,
45 };
46 #elif (CONFIG_SYS_NUM_DDR_CTLRS == 1) && (CONFIG_DIMM_SLOTS_PER_CTLR == 2)
47 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
48 	[0][0] = SPD_EEPROM_ADDRESS1,	/* controller 1 */
49 	[0][1] = SPD_EEPROM_ADDRESS2,	/* controller 1 */
50 };
51 #elif (CONFIG_SYS_NUM_DDR_CTLRS == 2) && (CONFIG_DIMM_SLOTS_PER_CTLR == 1)
52 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
53 	[0][0] = SPD_EEPROM_ADDRESS1,	/* controller 1 */
54 	[1][0] = SPD_EEPROM_ADDRESS2,	/* controller 2 */
55 };
56 #elif (CONFIG_SYS_NUM_DDR_CTLRS == 2) && (CONFIG_DIMM_SLOTS_PER_CTLR == 2)
57 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
58 	[0][0] = SPD_EEPROM_ADDRESS1,	/* controller 1 */
59 	[0][1] = SPD_EEPROM_ADDRESS2,	/* controller 1 */
60 	[1][0] = SPD_EEPROM_ADDRESS3,	/* controller 2 */
61 	[1][1] = SPD_EEPROM_ADDRESS4,	/* controller 2 */
62 };
63 #elif (CONFIG_SYS_NUM_DDR_CTLRS == 3) && (CONFIG_DIMM_SLOTS_PER_CTLR == 1)
64 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
65 	[0][0] = SPD_EEPROM_ADDRESS1,	/* controller 1 */
66 	[1][0] = SPD_EEPROM_ADDRESS2,	/* controller 2 */
67 	[2][0] = SPD_EEPROM_ADDRESS3,	/* controller 3 */
68 };
69 #elif (CONFIG_SYS_NUM_DDR_CTLRS == 3) && (CONFIG_DIMM_SLOTS_PER_CTLR == 2)
70 u8 spd_i2c_addr[CONFIG_SYS_NUM_DDR_CTLRS][CONFIG_DIMM_SLOTS_PER_CTLR] = {
71 	[0][0] = SPD_EEPROM_ADDRESS1,	/* controller 1 */
72 	[0][1] = SPD_EEPROM_ADDRESS2,	/* controller 1 */
73 	[1][0] = SPD_EEPROM_ADDRESS3,	/* controller 2 */
74 	[1][1] = SPD_EEPROM_ADDRESS4,	/* controller 2 */
75 	[2][0] = SPD_EEPROM_ADDRESS5,	/* controller 3 */
76 	[2][1] = SPD_EEPROM_ADDRESS6,	/* controller 3 */
77 };
78 
79 #endif
80 
81 #define SPD_SPA0_ADDRESS	0x36
82 #define SPD_SPA1_ADDRESS	0x37
83 
84 static void __get_spd(generic_spd_eeprom_t *spd, u8 i2c_address)
85 {
86 	int ret;
87 #ifdef CONFIG_SYS_FSL_DDR4
88 	uint8_t dummy = 0;
89 #endif
90 
91 	i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM);
92 
93 #ifdef CONFIG_SYS_FSL_DDR4
94 	/*
95 	 * DDR4 SPD has 384 to 512 bytes
96 	 * To access the lower 256 bytes, we need to set EE page address to 0
97 	 * To access the upper 256 bytes, we need to set EE page address to 1
98 	 * See Jedec standar No. 21-C for detail
99 	 */
100 	i2c_write(SPD_SPA0_ADDRESS, 0, 1, &dummy, 1);
101 	ret = i2c_read(i2c_address, 0, 1, (uchar *)spd, 256);
102 	if (!ret) {
103 		i2c_write(SPD_SPA1_ADDRESS, 0, 1, &dummy, 1);
104 		ret = i2c_read(i2c_address, 0, 1,
105 			       (uchar *)((ulong)spd + 256),
106 			       min(256,
107 				   (int)sizeof(generic_spd_eeprom_t) - 256));
108 	}
109 #else
110 	ret = i2c_read(i2c_address, 0, 1, (uchar *)spd,
111 				sizeof(generic_spd_eeprom_t));
112 #endif
113 
114 	if (ret) {
115 		if (i2c_address ==
116 #ifdef SPD_EEPROM_ADDRESS
117 				SPD_EEPROM_ADDRESS
118 #elif defined(SPD_EEPROM_ADDRESS1)
119 				SPD_EEPROM_ADDRESS1
120 #endif
121 				) {
122 			printf("DDR: failed to read SPD from address %u\n",
123 				i2c_address);
124 		} else {
125 			debug("DDR: failed to read SPD from address %u\n",
126 				i2c_address);
127 		}
128 		memset(spd, 0, sizeof(generic_spd_eeprom_t));
129 	}
130 }
131 
132 __attribute__((weak, alias("__get_spd")))
133 void get_spd(generic_spd_eeprom_t *spd, u8 i2c_address);
134 
135 /* This function allows boards to update SPD address */
136 __weak void update_spd_address(unsigned int ctrl_num,
137 			       unsigned int slot,
138 			       unsigned int *addr)
139 {
140 }
141 
142 void fsl_ddr_get_spd(generic_spd_eeprom_t *ctrl_dimms_spd,
143 		      unsigned int ctrl_num, unsigned int dimm_slots_per_ctrl)
144 {
145 	unsigned int i;
146 	unsigned int i2c_address = 0;
147 
148 	if (ctrl_num >= CONFIG_SYS_NUM_DDR_CTLRS) {
149 		printf("%s unexpected ctrl_num = %u\n", __FUNCTION__, ctrl_num);
150 		return;
151 	}
152 
153 	for (i = 0; i < dimm_slots_per_ctrl; i++) {
154 		i2c_address = spd_i2c_addr[ctrl_num][i];
155 		update_spd_address(ctrl_num, i, &i2c_address);
156 		get_spd(&(ctrl_dimms_spd[i]), i2c_address);
157 	}
158 }
159 #else
160 void fsl_ddr_get_spd(generic_spd_eeprom_t *ctrl_dimms_spd,
161 		      unsigned int ctrl_num, unsigned int dimm_slots_per_ctrl)
162 {
163 }
164 #endif /* SPD_EEPROM_ADDRESSx */
165 
166 /*
167  * ASSUMPTIONS:
168  *    - Same number of CONFIG_DIMM_SLOTS_PER_CTLR on each controller
169  *    - Same memory data bus width on all controllers
170  *
171  * NOTES:
172  *
173  * The memory controller and associated documentation use confusing
174  * terminology when referring to the orgranization of DRAM.
175  *
176  * Here is a terminology translation table:
177  *
178  * memory controller/documention  |industry   |this code  |signals
179  * -------------------------------|-----------|-----------|-----------------
180  * physical bank/bank		  |rank       |rank	  |chip select (CS)
181  * logical bank/sub-bank	  |bank       |bank	  |bank address (BA)
182  * page/row			  |row	      |page	  |row address
183  * ???				  |column     |column	  |column address
184  *
185  * The naming confusion is further exacerbated by the descriptions of the
186  * memory controller interleaving feature, where accesses are interleaved
187  * _BETWEEN_ two seperate memory controllers.  This is configured only in
188  * CS0_CONFIG[INTLV_CTL] of each memory controller.
189  *
190  * memory controller documentation | number of chip selects
191  *				   | per memory controller supported
192  * --------------------------------|-----------------------------------------
193  * cache line interleaving	   | 1 (CS0 only)
194  * page interleaving		   | 1 (CS0 only)
195  * bank interleaving		   | 1 (CS0 only)
196  * superbank interleraving	   | depends on bank (chip select)
197  *				   |   interleraving [rank interleaving]
198  *				   |   mode used on every memory controller
199  *
200  * Even further confusing is the existence of the interleaving feature
201  * _WITHIN_ each memory controller.  The feature is referred to in
202  * documentation as chip select interleaving or bank interleaving,
203  * although it is configured in the DDR_SDRAM_CFG field.
204  *
205  * Name of field		| documentation name	| this code
206  * -----------------------------|-----------------------|------------------
207  * DDR_SDRAM_CFG[BA_INTLV_CTL]	| Bank (chip select)	| rank interleaving
208  *				|  interleaving
209  */
210 
211 const char *step_string_tbl[] = {
212 	"STEP_GET_SPD",
213 	"STEP_COMPUTE_DIMM_PARMS",
214 	"STEP_COMPUTE_COMMON_PARMS",
215 	"STEP_GATHER_OPTS",
216 	"STEP_ASSIGN_ADDRESSES",
217 	"STEP_COMPUTE_REGS",
218 	"STEP_PROGRAM_REGS",
219 	"STEP_ALL"
220 };
221 
222 const char * step_to_string(unsigned int step) {
223 
224 	unsigned int s = __ilog2(step);
225 
226 	if ((1 << s) != step)
227 		return step_string_tbl[7];
228 
229 	if (s >= ARRAY_SIZE(step_string_tbl)) {
230 		printf("Error for the step in %s\n", __func__);
231 		s = 0;
232 	}
233 
234 	return step_string_tbl[s];
235 }
236 
237 static unsigned long long __step_assign_addresses(fsl_ddr_info_t *pinfo,
238 			  unsigned int dbw_cap_adj[])
239 {
240 	unsigned int i, j;
241 	unsigned long long total_mem, current_mem_base, total_ctlr_mem;
242 	unsigned long long rank_density, ctlr_density = 0;
243 	unsigned int first_ctrl = pinfo->first_ctrl;
244 	unsigned int last_ctrl = first_ctrl + pinfo->num_ctrls - 1;
245 
246 	/*
247 	 * If a reduced data width is requested, but the SPD
248 	 * specifies a physically wider device, adjust the
249 	 * computed dimm capacities accordingly before
250 	 * assigning addresses.
251 	 */
252 	for (i = first_ctrl; i <= last_ctrl; i++) {
253 		unsigned int found = 0;
254 
255 		switch (pinfo->memctl_opts[i].data_bus_width) {
256 		case 2:
257 			/* 16-bit */
258 			for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
259 				unsigned int dw;
260 				if (!pinfo->dimm_params[i][j].n_ranks)
261 					continue;
262 				dw = pinfo->dimm_params[i][j].primary_sdram_width;
263 				if ((dw == 72 || dw == 64)) {
264 					dbw_cap_adj[i] = 2;
265 					break;
266 				} else if ((dw == 40 || dw == 32)) {
267 					dbw_cap_adj[i] = 1;
268 					break;
269 				}
270 			}
271 			break;
272 
273 		case 1:
274 			/* 32-bit */
275 			for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
276 				unsigned int dw;
277 				dw = pinfo->dimm_params[i][j].data_width;
278 				if (pinfo->dimm_params[i][j].n_ranks
279 				    && (dw == 72 || dw == 64)) {
280 					/*
281 					 * FIXME: can't really do it
282 					 * like this because this just
283 					 * further reduces the memory
284 					 */
285 					found = 1;
286 					break;
287 				}
288 			}
289 			if (found) {
290 				dbw_cap_adj[i] = 1;
291 			}
292 			break;
293 
294 		case 0:
295 			/* 64-bit */
296 			break;
297 
298 		default:
299 			printf("unexpected data bus width "
300 				"specified controller %u\n", i);
301 			return 1;
302 		}
303 		debug("dbw_cap_adj[%d]=%d\n", i, dbw_cap_adj[i]);
304 	}
305 
306 	current_mem_base = pinfo->mem_base;
307 	total_mem = 0;
308 	if (pinfo->memctl_opts[first_ctrl].memctl_interleaving) {
309 		rank_density = pinfo->dimm_params[first_ctrl][0].rank_density >>
310 					dbw_cap_adj[first_ctrl];
311 		switch (pinfo->memctl_opts[first_ctrl].ba_intlv_ctl &
312 					FSL_DDR_CS0_CS1_CS2_CS3) {
313 		case FSL_DDR_CS0_CS1_CS2_CS3:
314 			ctlr_density = 4 * rank_density;
315 			break;
316 		case FSL_DDR_CS0_CS1:
317 		case FSL_DDR_CS0_CS1_AND_CS2_CS3:
318 			ctlr_density = 2 * rank_density;
319 			break;
320 		case FSL_DDR_CS2_CS3:
321 		default:
322 			ctlr_density = rank_density;
323 			break;
324 		}
325 		debug("rank density is 0x%llx, ctlr density is 0x%llx\n",
326 			rank_density, ctlr_density);
327 		for (i = first_ctrl; i <= last_ctrl; i++) {
328 			if (pinfo->memctl_opts[i].memctl_interleaving) {
329 				switch (pinfo->memctl_opts[i].memctl_interleaving_mode) {
330 				case FSL_DDR_256B_INTERLEAVING:
331 				case FSL_DDR_CACHE_LINE_INTERLEAVING:
332 				case FSL_DDR_PAGE_INTERLEAVING:
333 				case FSL_DDR_BANK_INTERLEAVING:
334 				case FSL_DDR_SUPERBANK_INTERLEAVING:
335 					total_ctlr_mem = 2 * ctlr_density;
336 					break;
337 				case FSL_DDR_3WAY_1KB_INTERLEAVING:
338 				case FSL_DDR_3WAY_4KB_INTERLEAVING:
339 				case FSL_DDR_3WAY_8KB_INTERLEAVING:
340 					total_ctlr_mem = 3 * ctlr_density;
341 					break;
342 				case FSL_DDR_4WAY_1KB_INTERLEAVING:
343 				case FSL_DDR_4WAY_4KB_INTERLEAVING:
344 				case FSL_DDR_4WAY_8KB_INTERLEAVING:
345 					total_ctlr_mem = 4 * ctlr_density;
346 					break;
347 				default:
348 					panic("Unknown interleaving mode");
349 				}
350 				pinfo->common_timing_params[i].base_address =
351 							current_mem_base;
352 				pinfo->common_timing_params[i].total_mem =
353 							total_ctlr_mem;
354 				total_mem = current_mem_base + total_ctlr_mem;
355 				debug("ctrl %d base 0x%llx\n", i, current_mem_base);
356 				debug("ctrl %d total 0x%llx\n", i, total_ctlr_mem);
357 			} else {
358 				/* when 3rd controller not interleaved */
359 				current_mem_base = total_mem;
360 				total_ctlr_mem = 0;
361 				pinfo->common_timing_params[i].base_address =
362 							current_mem_base;
363 				for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
364 					unsigned long long cap =
365 						pinfo->dimm_params[i][j].capacity >> dbw_cap_adj[i];
366 					pinfo->dimm_params[i][j].base_address =
367 						current_mem_base;
368 					debug("ctrl %d dimm %d base 0x%llx\n", i, j, current_mem_base);
369 					current_mem_base += cap;
370 					total_ctlr_mem += cap;
371 				}
372 				debug("ctrl %d total 0x%llx\n", i, total_ctlr_mem);
373 				pinfo->common_timing_params[i].total_mem =
374 							total_ctlr_mem;
375 				total_mem += total_ctlr_mem;
376 			}
377 		}
378 	} else {
379 		/*
380 		 * Simple linear assignment if memory
381 		 * controllers are not interleaved.
382 		 */
383 		for (i = first_ctrl; i <= last_ctrl; i++) {
384 			total_ctlr_mem = 0;
385 			pinfo->common_timing_params[i].base_address =
386 						current_mem_base;
387 			for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
388 				/* Compute DIMM base addresses. */
389 				unsigned long long cap =
390 					pinfo->dimm_params[i][j].capacity >> dbw_cap_adj[i];
391 				pinfo->dimm_params[i][j].base_address =
392 					current_mem_base;
393 				debug("ctrl %d dimm %d base 0x%llx\n", i, j, current_mem_base);
394 				current_mem_base += cap;
395 				total_ctlr_mem += cap;
396 			}
397 			debug("ctrl %d total 0x%llx\n", i, total_ctlr_mem);
398 			pinfo->common_timing_params[i].total_mem =
399 							total_ctlr_mem;
400 			total_mem += total_ctlr_mem;
401 		}
402 	}
403 	debug("Total mem by %s is 0x%llx\n", __func__, total_mem);
404 
405 	return total_mem;
406 }
407 
408 /* Use weak function to allow board file to override the address assignment */
409 __attribute__((weak, alias("__step_assign_addresses")))
410 unsigned long long step_assign_addresses(fsl_ddr_info_t *pinfo,
411 			  unsigned int dbw_cap_adj[]);
412 
413 unsigned long long
414 fsl_ddr_compute(fsl_ddr_info_t *pinfo, unsigned int start_step,
415 				       unsigned int size_only)
416 {
417 	unsigned int i, j;
418 	unsigned long long total_mem = 0;
419 	int assert_reset = 0;
420 	unsigned int first_ctrl =  pinfo->first_ctrl;
421 	unsigned int last_ctrl = first_ctrl + pinfo->num_ctrls - 1;
422 	__maybe_unused int retval;
423 	__maybe_unused bool goodspd = false;
424 	__maybe_unused int dimm_slots_per_ctrl = pinfo->dimm_slots_per_ctrl;
425 
426 	fsl_ddr_cfg_regs_t *ddr_reg = pinfo->fsl_ddr_config_reg;
427 	common_timing_params_t *timing_params = pinfo->common_timing_params;
428 	if (pinfo->board_need_mem_reset)
429 		assert_reset = pinfo->board_need_mem_reset();
430 
431 	/* data bus width capacity adjust shift amount */
432 	unsigned int dbw_capacity_adjust[CONFIG_SYS_NUM_DDR_CTLRS];
433 
434 	for (i = first_ctrl; i <= last_ctrl; i++)
435 		dbw_capacity_adjust[i] = 0;
436 
437 	debug("starting at step %u (%s)\n",
438 	      start_step, step_to_string(start_step));
439 
440 	switch (start_step) {
441 	case STEP_GET_SPD:
442 #if defined(CONFIG_DDR_SPD) || defined(CONFIG_SPD_EEPROM)
443 		/* STEP 1:  Gather all DIMM SPD data */
444 		for (i = first_ctrl; i <= last_ctrl; i++) {
445 			fsl_ddr_get_spd(pinfo->spd_installed_dimms[i], i,
446 					dimm_slots_per_ctrl);
447 		}
448 
449 	case STEP_COMPUTE_DIMM_PARMS:
450 		/* STEP 2:  Compute DIMM parameters from SPD data */
451 
452 		for (i = first_ctrl; i <= last_ctrl; i++) {
453 			for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
454 				generic_spd_eeprom_t *spd =
455 					&(pinfo->spd_installed_dimms[i][j]);
456 				dimm_params_t *pdimm =
457 					&(pinfo->dimm_params[i][j]);
458 				retval = compute_dimm_parameters(
459 							i, spd, pdimm, j);
460 #ifdef CONFIG_SYS_DDR_RAW_TIMING
461 				if (!j && retval) {
462 					printf("SPD error on controller %d! "
463 					"Trying fallback to raw timing "
464 					"calculation\n", i);
465 					retval = fsl_ddr_get_dimm_params(pdimm,
466 									 i, j);
467 				}
468 #else
469 				if (retval == 2) {
470 					printf("Error: compute_dimm_parameters"
471 					" non-zero returned FATAL value "
472 					"for memctl=%u dimm=%u\n", i, j);
473 					return 0;
474 				}
475 #endif
476 				if (retval) {
477 					debug("Warning: compute_dimm_parameters"
478 					" non-zero return value for memctl=%u "
479 					"dimm=%u\n", i, j);
480 				} else {
481 					goodspd = true;
482 				}
483 			}
484 		}
485 		if (!goodspd) {
486 			/*
487 			 * No valid SPD found
488 			 * Throw an error if this is for main memory, i.e.
489 			 * first_ctrl == 0. Otherwise, siliently return 0
490 			 * as the memory size.
491 			 */
492 			if (first_ctrl == 0)
493 				printf("Error: No valid SPD detected.\n");
494 
495 			return 0;
496 		}
497 #elif defined(CONFIG_SYS_DDR_RAW_TIMING)
498 	case STEP_COMPUTE_DIMM_PARMS:
499 		for (i = first_ctrl; i <= last_ctrl; i++) {
500 			for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
501 				dimm_params_t *pdimm =
502 					&(pinfo->dimm_params[i][j]);
503 				fsl_ddr_get_dimm_params(pdimm, i, j);
504 			}
505 		}
506 		debug("Filling dimm parameters from board specific file\n");
507 #endif
508 	case STEP_COMPUTE_COMMON_PARMS:
509 		/*
510 		 * STEP 3: Compute a common set of timing parameters
511 		 * suitable for all of the DIMMs on each memory controller
512 		 */
513 		for (i = first_ctrl; i <= last_ctrl; i++) {
514 			debug("Computing lowest common DIMM"
515 				" parameters for memctl=%u\n", i);
516 			compute_lowest_common_dimm_parameters
517 				(i,
518 				 pinfo->dimm_params[i],
519 				 &timing_params[i],
520 				 CONFIG_DIMM_SLOTS_PER_CTLR);
521 		}
522 
523 	case STEP_GATHER_OPTS:
524 		/* STEP 4:  Gather configuration requirements from user */
525 		for (i = first_ctrl; i <= last_ctrl; i++) {
526 			debug("Reloading memory controller "
527 				"configuration options for memctl=%u\n", i);
528 			/*
529 			 * This "reloads" the memory controller options
530 			 * to defaults.  If the user "edits" an option,
531 			 * next_step points to the step after this,
532 			 * which is currently STEP_ASSIGN_ADDRESSES.
533 			 */
534 			populate_memctl_options(
535 					&timing_params[i],
536 					&pinfo->memctl_opts[i],
537 					pinfo->dimm_params[i], i);
538 			/*
539 			 * For RDIMMs, JEDEC spec requires clocks to be stable
540 			 * before reset signal is deasserted. For the boards
541 			 * using fixed parameters, this function should be
542 			 * be called from board init file.
543 			 */
544 			if (timing_params[i].all_dimms_registered)
545 				assert_reset = 1;
546 		}
547 		if (assert_reset && !size_only) {
548 			if (pinfo->board_mem_reset) {
549 				debug("Asserting mem reset\n");
550 				pinfo->board_mem_reset();
551 			} else {
552 				debug("Asserting mem reset missing\n");
553 			}
554 		}
555 
556 	case STEP_ASSIGN_ADDRESSES:
557 		/* STEP 5:  Assign addresses to chip selects */
558 		check_interleaving_options(pinfo);
559 		total_mem = step_assign_addresses(pinfo, dbw_capacity_adjust);
560 		debug("Total mem %llu assigned\n", total_mem);
561 
562 	case STEP_COMPUTE_REGS:
563 		/* STEP 6:  compute controller register values */
564 		debug("FSL Memory ctrl register computation\n");
565 		for (i = first_ctrl; i <= last_ctrl; i++) {
566 			if (timing_params[i].ndimms_present == 0) {
567 				memset(&ddr_reg[i], 0,
568 					sizeof(fsl_ddr_cfg_regs_t));
569 				continue;
570 			}
571 
572 			compute_fsl_memctl_config_regs
573 				(i,
574 				 &pinfo->memctl_opts[i],
575 				 &ddr_reg[i], &timing_params[i],
576 				 pinfo->dimm_params[i],
577 				 dbw_capacity_adjust[i],
578 				 size_only);
579 		}
580 
581 	default:
582 		break;
583 	}
584 
585 	{
586 		/*
587 		 * Compute the amount of memory available just by
588 		 * looking for the highest valid CSn_BNDS value.
589 		 * This allows us to also experiment with using
590 		 * only CS0 when using dual-rank DIMMs.
591 		 */
592 		unsigned int max_end = 0;
593 
594 		for (i = first_ctrl; i <= last_ctrl; i++) {
595 			for (j = 0; j < CONFIG_CHIP_SELECTS_PER_CTRL; j++) {
596 				fsl_ddr_cfg_regs_t *reg = &ddr_reg[i];
597 				if (reg->cs[j].config & 0x80000000) {
598 					unsigned int end;
599 					/*
600 					 * 0xfffffff is a special value we put
601 					 * for unused bnds
602 					 */
603 					if (reg->cs[j].bnds == 0xffffffff)
604 						continue;
605 					end = reg->cs[j].bnds & 0xffff;
606 					if (end > max_end) {
607 						max_end = end;
608 					}
609 				}
610 			}
611 		}
612 
613 		total_mem = 1 + (((unsigned long long)max_end << 24ULL) |
614 			    0xFFFFFFULL) - pinfo->mem_base;
615 	}
616 
617 	return total_mem;
618 }
619 
620 phys_size_t __fsl_ddr_sdram(fsl_ddr_info_t *pinfo)
621 {
622 	unsigned int i, first_ctrl, last_ctrl;
623 #ifdef CONFIG_PPC
624 	unsigned int law_memctl = LAW_TRGT_IF_DDR_1;
625 #endif
626 	unsigned long long total_memory;
627 	int deassert_reset = 0;
628 
629 	first_ctrl = pinfo->first_ctrl;
630 	last_ctrl = first_ctrl + pinfo->num_ctrls - 1;
631 
632 	/* Compute it once normally. */
633 #ifdef CONFIG_FSL_DDR_INTERACTIVE
634 	if (tstc() && (getc() == 'd')) {	/* we got a key press of 'd' */
635 		total_memory = fsl_ddr_interactive(pinfo, 0);
636 	} else if (fsl_ddr_interactive_env_var_exists()) {
637 		total_memory = fsl_ddr_interactive(pinfo, 1);
638 	} else
639 #endif
640 		total_memory = fsl_ddr_compute(pinfo, STEP_GET_SPD, 0);
641 
642 	/* setup 3-way interleaving before enabling DDRC */
643 	switch (pinfo->memctl_opts[first_ctrl].memctl_interleaving_mode) {
644 	case FSL_DDR_3WAY_1KB_INTERLEAVING:
645 	case FSL_DDR_3WAY_4KB_INTERLEAVING:
646 	case FSL_DDR_3WAY_8KB_INTERLEAVING:
647 		fsl_ddr_set_intl3r(
648 			pinfo->memctl_opts[first_ctrl].
649 			memctl_interleaving_mode);
650 		break;
651 	default:
652 		break;
653 	}
654 
655 	/*
656 	 * Program configuration registers.
657 	 * JEDEC specs requires clocks to be stable before deasserting reset
658 	 * for RDIMMs. Clocks start after chip select is enabled and clock
659 	 * control register is set. During step 1, all controllers have their
660 	 * registers set but not enabled. Step 2 proceeds after deasserting
661 	 * reset through board FPGA or GPIO.
662 	 * For non-registered DIMMs, initialization can go through but it is
663 	 * also OK to follow the same flow.
664 	 */
665 	if (pinfo->board_need_mem_reset)
666 		deassert_reset = pinfo->board_need_mem_reset();
667 	for (i = first_ctrl; i <= last_ctrl; i++) {
668 		if (pinfo->common_timing_params[i].all_dimms_registered)
669 			deassert_reset = 1;
670 	}
671 	for (i = first_ctrl; i <= last_ctrl; i++) {
672 		debug("Programming controller %u\n", i);
673 		if (pinfo->common_timing_params[i].ndimms_present == 0) {
674 			debug("No dimms present on controller %u; "
675 					"skipping programming\n", i);
676 			continue;
677 		}
678 		/*
679 		 * The following call with step = 1 returns before enabling
680 		 * the controller. It has to finish with step = 2 later.
681 		 */
682 		fsl_ddr_set_memctl_regs(&(pinfo->fsl_ddr_config_reg[i]), i,
683 					deassert_reset ? 1 : 0);
684 	}
685 	if (deassert_reset) {
686 		/* Use board FPGA or GPIO to deassert reset signal */
687 		if (pinfo->board_mem_de_reset) {
688 			debug("Deasserting mem reset\n");
689 			pinfo->board_mem_de_reset();
690 		} else {
691 			debug("Deasserting mem reset missing\n");
692 		}
693 		for (i = first_ctrl; i <= last_ctrl; i++) {
694 			/* Call with step = 2 to continue initialization */
695 			fsl_ddr_set_memctl_regs(&(pinfo->fsl_ddr_config_reg[i]),
696 						i, 2);
697 		}
698 	}
699 
700 #ifdef CONFIG_FSL_DDR_SYNC_REFRESH
701 	fsl_ddr_sync_memctl_refresh(first_ctrl, last_ctrl);
702 #endif
703 
704 #ifdef CONFIG_PPC
705 	/* program LAWs */
706 	for (i = first_ctrl; i <= last_ctrl; i++) {
707 		if (pinfo->memctl_opts[i].memctl_interleaving) {
708 			switch (pinfo->memctl_opts[i].
709 				memctl_interleaving_mode) {
710 			case FSL_DDR_CACHE_LINE_INTERLEAVING:
711 			case FSL_DDR_PAGE_INTERLEAVING:
712 			case FSL_DDR_BANK_INTERLEAVING:
713 			case FSL_DDR_SUPERBANK_INTERLEAVING:
714 				if (i % 2)
715 					break;
716 				if (i == 0) {
717 					law_memctl = LAW_TRGT_IF_DDR_INTRLV;
718 					fsl_ddr_set_lawbar(
719 						&pinfo->common_timing_params[i],
720 						law_memctl, i);
721 				}
722 #if CONFIG_SYS_NUM_DDR_CTLRS > 3
723 				else if (i == 2) {
724 					law_memctl = LAW_TRGT_IF_DDR_INTLV_34;
725 					fsl_ddr_set_lawbar(
726 						&pinfo->common_timing_params[i],
727 						law_memctl, i);
728 				}
729 #endif
730 				break;
731 			case FSL_DDR_3WAY_1KB_INTERLEAVING:
732 			case FSL_DDR_3WAY_4KB_INTERLEAVING:
733 			case FSL_DDR_3WAY_8KB_INTERLEAVING:
734 				law_memctl = LAW_TRGT_IF_DDR_INTLV_123;
735 				if (i == 0) {
736 					fsl_ddr_set_lawbar(
737 						&pinfo->common_timing_params[i],
738 						law_memctl, i);
739 				}
740 				break;
741 			case FSL_DDR_4WAY_1KB_INTERLEAVING:
742 			case FSL_DDR_4WAY_4KB_INTERLEAVING:
743 			case FSL_DDR_4WAY_8KB_INTERLEAVING:
744 				law_memctl = LAW_TRGT_IF_DDR_INTLV_1234;
745 				if (i == 0)
746 					fsl_ddr_set_lawbar(
747 						&pinfo->common_timing_params[i],
748 						law_memctl, i);
749 				/* place holder for future 4-way interleaving */
750 				break;
751 			default:
752 				break;
753 			}
754 		} else {
755 			switch (i) {
756 			case 0:
757 				law_memctl = LAW_TRGT_IF_DDR_1;
758 				break;
759 			case 1:
760 				law_memctl = LAW_TRGT_IF_DDR_2;
761 				break;
762 			case 2:
763 				law_memctl = LAW_TRGT_IF_DDR_3;
764 				break;
765 			case 3:
766 				law_memctl = LAW_TRGT_IF_DDR_4;
767 				break;
768 			default:
769 				break;
770 			}
771 			fsl_ddr_set_lawbar(&pinfo->common_timing_params[i],
772 					   law_memctl, i);
773 		}
774 	}
775 #endif
776 
777 	debug("total_memory by %s = %llu\n", __func__, total_memory);
778 
779 #if !defined(CONFIG_PHYS_64BIT)
780 	/* Check for 4G or more.  Bad. */
781 	if ((first_ctrl == 0) && (total_memory >= (1ull << 32))) {
782 		puts("Detected ");
783 		print_size(total_memory, " of memory\n");
784 		printf("       This U-Boot only supports < 4G of DDR\n");
785 		printf("       You could rebuild it with CONFIG_PHYS_64BIT\n");
786 		printf("       "); /* re-align to match init_dram print */
787 		total_memory = CONFIG_MAX_MEM_MAPPED;
788 	}
789 #endif
790 
791 	return total_memory;
792 }
793 
794 /*
795  * fsl_ddr_sdram(void) -- this is the main function to be
796  * called by dram_init() in the board file.
797  *
798  * It returns amount of memory configured in bytes.
799  */
800 phys_size_t fsl_ddr_sdram(void)
801 {
802 	fsl_ddr_info_t info;
803 
804 	/* Reset info structure. */
805 	memset(&info, 0, sizeof(fsl_ddr_info_t));
806 	info.mem_base = CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY;
807 	info.first_ctrl = 0;
808 	info.num_ctrls = CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS;
809 	info.dimm_slots_per_ctrl = CONFIG_DIMM_SLOTS_PER_CTLR;
810 	info.board_need_mem_reset = board_need_mem_reset;
811 	info.board_mem_reset = board_assert_mem_reset;
812 	info.board_mem_de_reset = board_deassert_mem_reset;
813 	remove_unused_controllers(&info);
814 
815 	return __fsl_ddr_sdram(&info);
816 }
817 
818 #ifdef CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
819 phys_size_t fsl_other_ddr_sdram(unsigned long long base,
820 				unsigned int first_ctrl,
821 				unsigned int num_ctrls,
822 				unsigned int dimm_slots_per_ctrl,
823 				int (*board_need_reset)(void),
824 				void (*board_reset)(void),
825 				void (*board_de_reset)(void))
826 {
827 	fsl_ddr_info_t info;
828 
829 	/* Reset info structure. */
830 	memset(&info, 0, sizeof(fsl_ddr_info_t));
831 	info.mem_base = base;
832 	info.first_ctrl = first_ctrl;
833 	info.num_ctrls = num_ctrls;
834 	info.dimm_slots_per_ctrl = dimm_slots_per_ctrl;
835 	info.board_need_mem_reset = board_need_reset;
836 	info.board_mem_reset = board_reset;
837 	info.board_mem_de_reset = board_de_reset;
838 
839 	return __fsl_ddr_sdram(&info);
840 }
841 #endif
842 
843 /*
844  * fsl_ddr_sdram_size(first_ctrl, last_intlv) - This function only returns the
845  * size of the total memory without setting ddr control registers.
846  */
847 phys_size_t
848 fsl_ddr_sdram_size(void)
849 {
850 	fsl_ddr_info_t  info;
851 	unsigned long long total_memory = 0;
852 
853 	memset(&info, 0 , sizeof(fsl_ddr_info_t));
854 	info.mem_base = CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY;
855 	info.first_ctrl = 0;
856 	info.num_ctrls = CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS;
857 	info.dimm_slots_per_ctrl = CONFIG_DIMM_SLOTS_PER_CTLR;
858 	info.board_need_mem_reset = NULL;
859 	remove_unused_controllers(&info);
860 
861 	/* Compute it once normally. */
862 	total_memory = fsl_ddr_compute(&info, STEP_GET_SPD, 1);
863 
864 	return total_memory;
865 }
866