arch/powerpc/cpu/mpc8xxx/ddr/main.c

   1 /*
   2  * Copyright 2008 Freescale Semiconductor, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * Version 2 as published by the Free Software Foundation.
   7  */
   8
   9 /*
  10  * Generic driver for Freescale DDR/DDR2/DDR3 memory controller.
  11  * Based on code from spd_sdram.c
  12  * Author: James Yang [at freescale.com]
  13  */
  14
  15 #include <common.h>
  16 #include <asm/fsl_ddr_sdram.h>
  17
  18 #include "ddr.h"
  19
  20 extern void fsl_ddr_set_lawbar(
  21                 const common_timing_params_t *memctl_common_params,
  22                 unsigned int memctl_interleaved,
  23                 unsigned int ctrl_num);
  24
  25 /* processor specific function */
  26 extern void fsl_ddr_set_memctl_regs(const fsl_ddr_cfg_regs_t *regs,
  27                                    unsigned int ctrl_num);
  28
  29 /* Board-specific functions defined in each board's ddr.c */
  30 extern void fsl_ddr_get_spd(generic_spd_eeprom_t *ctrl_dimms_spd,
  31                            unsigned int ctrl_num);
  32
  33 /*
  34  * ASSUMPTIONS:
  35  *    - Same number of CONFIG_DIMM_SLOTS_PER_CTLR on each controller
  36  *    - Same memory data bus width on all controllers
  37  *
  38  * NOTES:
  39  *
  40  * The memory controller and associated documentation use confusing
  41  * terminology when referring to the orgranization of DRAM.
  42  *
  43  * Here is a terminology translation table:
  44  *
  45  * memory controller/documention  |industry   |this code  |signals
  46  * -------------------------------|-----------|-----------|-----------------
  47  * physical bank/bank             |rank       |rank       |chip select (CS)
  48  * logical bank/sub-bank          |bank       |bank       |bank address (BA)
  49  * page/row                       |row        |page       |row address
  50  * ???                            |column     |column     |column address
  51  *
  52  * The naming confusion is further exacerbated by the descriptions of the
  53  * memory controller interleaving feature, where accesses are interleaved
  54  * _BETWEEN_ two seperate memory controllers.  This is configured only in
  55  * CS0_CONFIG[INTLV_CTL] of each memory controller.
  56  *
  57  * memory controller documentation | number of chip selects
  58  *                                 | per memory controller supported
  59  * --------------------------------|-----------------------------------------
  60  * cache line interleaving         | 1 (CS0 only)
  61  * page interleaving               | 1 (CS0 only)
  62  * bank interleaving               | 1 (CS0 only)
  63  * superbank interleraving         | depends on bank (chip select)
  64  *                                 |   interleraving [rank interleaving]
  65  *                                 |   mode used on every memory controller
  66  *
  67  * Even further confusing is the existence of the interleaving feature
  68  * _WITHIN_ each memory controller.  The feature is referred to in
  69  * documentation as chip select interleaving or bank interleaving,
  70  * although it is configured in the DDR_SDRAM_CFG field.
  71  *
  72  * Name of field                | documentation name    | this code
  73  * -----------------------------|-----------------------|------------------
  74  * DDR_SDRAM_CFG[BA_INTLV_CTL]  | Bank (chip select)    | rank interleaving
  75  *                              |  interleaving
  76  */
  77
  78 #ifdef DEBUG
  79 const char *step_string_tbl[] = {
  80         "STEP_GET_SPD",
  81         "STEP_COMPUTE_DIMM_PARMS",
  82         "STEP_COMPUTE_COMMON_PARMS",
  83         "STEP_GATHER_OPTS",
  84         "STEP_ASSIGN_ADDRESSES",
  85         "STEP_COMPUTE_REGS",
  86         "STEP_PROGRAM_REGS",
  87         "STEP_ALL"
  88 };
  89
  90 const char * step_to_string(unsigned int step) {
  91
  92         unsigned int s = __ilog2(step);
  93
  94         if ((1 << s) != step)
  95                 return step_string_tbl[7];
  96
  97         return step_string_tbl[s];
  98 }
  99 #endif
 100
 101 int step_assign_addresses(fsl_ddr_info_t *pinfo,
 102                           unsigned int dbw_cap_adj[],
 103                           unsigned int *memctl_interleaving,
 104                           unsigned int *rank_interleaving)
 105 {
 106         int i, j;
 107
 108         /*
 109          * If a reduced data width is requested, but the SPD
 110          * specifies a physically wider device, adjust the
 111          * computed dimm capacities accordingly before
 112          * assigning addresses.
 113          */
 114         for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 115                 unsigned int found = 0;
 116
 117                 switch (pinfo->memctl_opts[i].data_bus_width) {
 118                 case 2:
 119                         /* 16-bit */
 120                         printf("can't handle 16-bit mode yet\n");
 121                         break;
 122
 123                 case 1:
 124                         /* 32-bit */
 125                         for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
 126                                 unsigned int dw;
 127                                 dw = pinfo->dimm_params[i][j].data_width;
 128                                 if (pinfo->dimm_params[i][j].n_ranks
 129                                     && (dw == 72 || dw == 64)) {
 130                                         /*
 131                                          * FIXME: can't really do it
 132                                          * like this because this just
 133                                          * further reduces the memory
 134                                          */
 135                                         found = 1;
 136                                         break;
 137                                 }
 138                         }
 139                         if (found) {
 140                                 dbw_cap_adj[i] = 1;
 141                         }
 142                         break;
 143
 144                 case 0:
 145                         /* 64-bit */
 146                         break;
 147
 148                 default:
 149                         printf("unexpected data bus width "
 150                                 "specified controller %u\n", i);
 151                         return 1;
 152                 }
 153         }
 154
 155         /*
 156          * Check if all controllers are configured for memory
 157          * controller interleaving.
 158          */
 159         j = 0;
 160         for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 161                 if (pinfo->memctl_opts[i].memctl_interleaving) {
 162                         j++;
 163                 }
 164         }
 165         if (j == 2)
 166                 *memctl_interleaving = 1;
 167
 168         /* Check that all controllers are rank interleaving. */
 169         j = 0;
 170         for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 171                 if (pinfo->memctl_opts[i].ba_intlv_ctl) {
 172                         j++;
 173                 }
 174         }
 175         if (j == 2)
 176                 *rank_interleaving = 1;
 177
 178         if (*memctl_interleaving) {
 179                 unsigned long long addr, total_mem_per_ctlr = 0;
 180                 /*
 181                  * If interleaving between memory controllers,
 182                  * make each controller start at a base address
 183                  * of 0.
 184                  *
 185                  * Also, if bank interleaving (chip select
 186                  * interleaving) is enabled on each memory
 187                  * controller, CS0 needs to be programmed to
 188                  * cover the entire memory range on that memory
 189                  * controller
 190                  *
 191                  * Bank interleaving also implies that each
 192                  * addressed chip select is identical in size.
 193                  */
 194
 195                 for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 196                         addr = 0;
 197                         pinfo->common_timing_params[i].base_address = 0ull;
 198                         for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
 199                                 unsigned long long cap
 200                                         = pinfo->dimm_params[i][j].capacity;
 201
 202                                 pinfo->dimm_params[i][j].base_address = addr;
 203                                 addr += cap >> dbw_cap_adj[i];
 204                                 total_mem_per_ctlr += cap >> dbw_cap_adj[i];
 205                         }
 206                 }
 207                 pinfo->common_timing_params[0].total_mem = total_mem_per_ctlr;
 208         } else {
 209                 /*
 210                  * Simple linear assignment if memory
 211                  * controllers are not interleaved.
 212                  */
 213                 unsigned long long cur_memsize = 0;
 214                 for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 215                         u64 total_mem_per_ctlr = 0;
 216                         pinfo->common_timing_params[i].base_address =
 217                                                 cur_memsize;
 218                         for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
 219                                 /* Compute DIMM base addresses. */
 220                                 unsigned long long cap =
 221                                         pinfo->dimm_params[i][j].capacity;
 222                                 pinfo->dimm_params[i][j].base_address =
 223                                         cur_memsize;
 224                                 cur_memsize += cap >> dbw_cap_adj[i];
 225                                 total_mem_per_ctlr += cap >> dbw_cap_adj[i];
 226                         }
 227                         pinfo->common_timing_params[i].total_mem =
 228                                                         total_mem_per_ctlr;
 229                 }
 230         }
 231
 232         return 0;
 233 }
 234
 235 unsigned long long
 236 fsl_ddr_compute(fsl_ddr_info_t *pinfo, unsigned int start_step)
 237 {
 238         unsigned int i, j;
 239         unsigned int all_controllers_memctl_interleaving = 0;
 240         unsigned int all_controllers_rank_interleaving = 0;
 241         unsigned long long total_mem = 0;
 242
 243         fsl_ddr_cfg_regs_t *ddr_reg = pinfo->fsl_ddr_config_reg;
 244         common_timing_params_t *timing_params = pinfo->common_timing_params;
 245
 246         /* data bus width capacity adjust shift amount */
 247         unsigned int dbw_capacity_adjust[CONFIG_NUM_DDR_CONTROLLERS];
 248
 249         for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 250                 dbw_capacity_adjust[i] = 0;
 251         }
 252
 253         debug("starting at step %u (%s)\n",
 254               start_step, step_to_string(start_step));
 255
 256         switch (start_step) {
 257         case STEP_GET_SPD:
 258                 /* STEP 1:  Gather all DIMM SPD data */
 259                 for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 260                         fsl_ddr_get_spd(pinfo->spd_installed_dimms[i], i);
 261                 }
 262
 263         case STEP_COMPUTE_DIMM_PARMS:
 264                 /* STEP 2:  Compute DIMM parameters from SPD data */
 265
 266                 for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 267                         for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
 268                                 unsigned int retval;
 269                                 generic_spd_eeprom_t *spd =
 270                                         &(pinfo->spd_installed_dimms[i][j]);
 271                                 dimm_params_t *pdimm =
 272                                         &(pinfo->dimm_params[i][j]);
 273
 274                                 retval = compute_dimm_parameters(spd, pdimm, i);
 275                                 if (retval == 2) {
 276                                         printf("Error: compute_dimm_parameters"
 277                                         " non-zero returned FATAL value "
 278                                         "for memctl=%u dimm=%u\n", i, j);
 279                                         return 0;
 280                                 }
 281                                 if (retval) {
 282                                         debug("Warning: compute_dimm_parameters"
 283                                         " non-zero return value for memctl=%u "
 284                                         "dimm=%u\n", i, j);
 285                                 }
 286                         }
 287                 }
 288
 289         case STEP_COMPUTE_COMMON_PARMS:
 290                 /*
 291                  * STEP 3: Compute a common set of timing parameters
 292                  * suitable for all of the DIMMs on each memory controller
 293                  */
 294                 for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 295                         debug("Computing lowest common DIMM"
 296                                 " parameters for memctl=%u\n", i);
 297                         compute_lowest_common_dimm_parameters(
 298                                 pinfo->dimm_params[i],
 299                                 &timing_params[i],
 300                                 CONFIG_DIMM_SLOTS_PER_CTLR);
 301                 }
 302
 303         case STEP_GATHER_OPTS:
 304                 /* STEP 4:  Gather configuration requirements from user */
 305                 for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 306                         debug("Reloading memory controller "
 307                                 "configuration options for memctl=%u\n", i);
 308                         /*
 309                          * This "reloads" the memory controller options
 310                          * to defaults.  If the user "edits" an option,
 311                          * next_step points to the step after this,
 312                          * which is currently STEP_ASSIGN_ADDRESSES.
 313                          */
 314                         populate_memctl_options(
 315                                         timing_params[i].all_DIMMs_registered,
 316                                         &pinfo->memctl_opts[i],
 317                                         pinfo->dimm_params[i], i);
 318                 }
 319
 320         case STEP_ASSIGN_ADDRESSES:
 321                 /* STEP 5:  Assign addresses to chip selects */
 322                 step_assign_addresses(pinfo,
 323                                 dbw_capacity_adjust,
 324                                 &all_controllers_memctl_interleaving,
 325                                 &all_controllers_rank_interleaving);
 326
 327         case STEP_COMPUTE_REGS:
 328                 /* STEP 6:  compute controller register values */
 329                 debug("FSL Memory ctrl cg register computation\n");
 330                 for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 331                         if (timing_params[i].ndimms_present == 0) {
 332                                 memset(&ddr_reg[i], 0,
 333                                         sizeof(fsl_ddr_cfg_regs_t));
 334                                 continue;
 335                         }
 336
 337                         compute_fsl_memctl_config_regs(
 338                                         &pinfo->memctl_opts[i],
 339                                         &ddr_reg[i], &timing_params[i],
 340                                         pinfo->dimm_params[i],
 341                                         dbw_capacity_adjust[i]);
 342                 }
 343
 344         default:
 345                 break;
 346         }
 347
 348         /* Compute the total amount of memory. */
 349
 350         /*
 351          * If bank interleaving but NOT memory controller interleaving
 352          * CS_BNDS describe the quantity of memory on each memory
 353          * controller, so the total is the sum across.
 354          */
 355         if (!all_controllers_memctl_interleaving
 356             && all_controllers_rank_interleaving) {
 357                 total_mem = 0;
 358                 for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 359                         total_mem += timing_params[i].total_mem;
 360                 }
 361
 362         } else {
 363                 /*
 364                  * Compute the amount of memory available just by
 365                  * looking for the highest valid CSn_BNDS value.
 366                  * This allows us to also experiment with using
 367                  * only CS0 when using dual-rank DIMMs.
 368                  */
 369                 unsigned int max_end = 0;
 370
 371                 for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 372                         for (j = 0; j < CONFIG_CHIP_SELECTS_PER_CTRL; j++) {
 373                                 fsl_ddr_cfg_regs_t *reg = &ddr_reg[i];
 374                                 if (reg->cs[j].config & 0x80000000) {
 375                                         unsigned int end;
 376                                         end = reg->cs[j].bnds & 0xFFF;
 377                                         if (end > max_end) {
 378                                                 max_end = end;
 379                                         }
 380                                 }
 381                         }
 382                 }
 383
 384                 total_mem = 1 + (((unsigned long long)max_end << 24ULL)
 385                                     | 0xFFFFFFULL);
 386         }
 387
 388         return total_mem;
 389 }
 390
 391 /*
 392  * fsl_ddr_sdram() -- this is the main function to be called by
 393  *      initdram() in the board file.
 394  *
 395  * It returns amount of memory configured in bytes.
 396  */
 397 phys_size_t fsl_ddr_sdram(void)
 398 {
 399         unsigned int i;
 400         unsigned int memctl_interleaved;
 401         unsigned long long total_memory;
 402         fsl_ddr_info_t info;
 403
 404         /* Reset info structure. */
 405         memset(&info, 0, sizeof(fsl_ddr_info_t));
 406
 407         /* Compute it once normally. */
 408         total_memory = fsl_ddr_compute(&info, STEP_GET_SPD);
 409
 410         /* Check for memory controller interleaving. */
 411         memctl_interleaved = 0;
 412         for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 413                 memctl_interleaved +=
 414                         info.memctl_opts[i].memctl_interleaving;
 415         }
 416
 417         if (memctl_interleaved) {
 418                 if (memctl_interleaved == CONFIG_NUM_DDR_CONTROLLERS) {
 419                         debug("memctl interleaving\n");
 420                         /*
 421                          * Change the meaning of memctl_interleaved
 422                          * to be "boolean".
 423                          */
 424                         memctl_interleaved = 1;
 425                 } else {
 426                         printf("Warning: memctl interleaving not "
 427                                 "properly configured on all controllers\n");
 428                         memctl_interleaved = 0;
 429                         for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++)
 430                                 info.memctl_opts[i].memctl_interleaving = 0;
 431                         debug("Recomputing with memctl_interleaving off.\n");
 432                         total_memory = fsl_ddr_compute(&info,
 433                                                        STEP_ASSIGN_ADDRESSES);
 434                 }
 435         }
 436
 437         /* Program configuration registers. */
 438         for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 439                 debug("Programming controller %u\n", i);
 440                 if (info.common_timing_params[i].ndimms_present == 0) {
 441                         debug("No dimms present on controller %u; "
 442                                         "skipping programming\n", i);
 443                         continue;
 444                 }
 445
 446                 fsl_ddr_set_memctl_regs(&(info.fsl_ddr_config_reg[i]), i);
 447         }
 448
 449         if (memctl_interleaved) {
 450                 const unsigned int ctrl_num = 0;
 451
 452                 /* Only set LAWBAR1 if memory controller interleaving is on. */
 453                 fsl_ddr_set_lawbar(&info.common_timing_params[0],
 454                                          memctl_interleaved, ctrl_num);
 455         } else {
 456                 /*
 457                  * Memory controller interleaving is NOT on;
 458                  * set each lawbar individually.
 459                  */
 460                 for (i = 0; i < CONFIG_NUM_DDR_CONTROLLERS; i++) {
 461                         fsl_ddr_set_lawbar(&info.common_timing_params[i],
 462                                                  0, i);
 463                 }
 464         }
 465
 466         debug("total_memory = %llu\n", total_memory);
 467
 468 #if !defined(CONFIG_PHYS_64BIT)
 469         /* Check for 4G or more.  Bad. */
 470         if (total_memory >= (1ull << 32)) {
 471                 printf("Detected %lld MB of memory\n", total_memory >> 20);
 472                 printf("This U-Boot only supports < 4G of DDR\n");
 473                 printf("You could rebuild it with CONFIG_PHYS_64BIT\n");
 474                 total_memory = CONFIG_MAX_MEM_MAPPED;
 475         }
 476 #endif
 477
 478         return total_memory;
 479 }