drivers/memory/atmel-ebi.c

   1 /*
   2  * EBI driver for Atmel chips
   3  * inspired by the fsl weim bus driver
   4  *
   5  * Copyright (C) 2013 Jean-Jacques Hiblot <jjhiblot@traphandler.com>
   6  *
   7  * This file is licensed under the terms of the GNU General Public
   8  * License version 2. This program is licensed "as is" without any
   9  * warranty of any kind, whether express or implied.
  10  */
  11
  12 #include <linux/clk.h>
  13 #include <linux/io.h>
  14 #include <linux/mfd/syscon.h>
  15 #include <linux/mfd/syscon/atmel-matrix.h>
  16 #include <linux/mfd/syscon/atmel-smc.h>
  17 #include <linux/init.h>
  18 #include <linux/of_device.h>
  19 #include <linux/regmap.h>
  20
  21 struct atmel_ebi_dev_config {
  22         int cs;
  23         struct atmel_smc_cs_conf smcconf;
  24 };
  25
  26 struct atmel_ebi;
  27
  28 struct atmel_ebi_dev {
  29         struct list_head node;
  30         struct atmel_ebi *ebi;
  31         u32 mode;
  32         int numcs;
  33         struct atmel_ebi_dev_config configs[];
  34 };
  35
  36 struct atmel_ebi_caps {
  37         unsigned int available_cs;
  38         unsigned int ebi_csa_offs;
  39         void (*get_config)(struct atmel_ebi_dev *ebid,
  40                            struct atmel_ebi_dev_config *conf);
  41         int (*xlate_config)(struct atmel_ebi_dev *ebid,
  42                             struct device_node *configs_np,
  43                             struct atmel_ebi_dev_config *conf);
  44         void (*apply_config)(struct atmel_ebi_dev *ebid,
  45                              struct atmel_ebi_dev_config *conf);
  46 };
  47
  48 struct atmel_ebi {
  49         struct clk *clk;
  50         struct regmap *matrix;
  51         struct  {
  52                 struct regmap *regmap;
  53                 struct clk *clk;
  54         } smc;
  55
  56         struct device *dev;
  57         const struct atmel_ebi_caps *caps;
  58         struct list_head devs;
  59 };
  60
  61 struct atmel_smc_timing_xlate {
  62         const char *name;
  63         int (*converter)(struct atmel_smc_cs_conf *conf,
  64                          unsigned int shift, unsigned int nycles);
  65         unsigned int shift;
  66 };
  67
  68 #define ATMEL_SMC_SETUP_XLATE(nm, pos)  \
  69         { .name = nm, .converter = atmel_smc_cs_conf_set_setup, .shift = pos}
  70
  71 #define ATMEL_SMC_PULSE_XLATE(nm, pos)  \
  72         { .name = nm, .converter = atmel_smc_cs_conf_set_pulse, .shift = pos}
  73
  74 #define ATMEL_SMC_CYCLE_XLATE(nm, pos)  \
  75         { .name = nm, .converter = atmel_smc_cs_conf_set_cycle, .shift = pos}
  76
  77 static void at91sam9_ebi_get_config(struct atmel_ebi_dev *ebid,
  78                                     struct atmel_ebi_dev_config *conf)
  79 {
  80         atmel_smc_cs_conf_get(ebid->ebi->smc.regmap, conf->cs,
  81                               &conf->smcconf);
  82 }
  83
  84 static void sama5_ebi_get_config(struct atmel_ebi_dev *ebid,
  85                                  struct atmel_ebi_dev_config *conf)
  86 {
  87         atmel_hsmc_cs_conf_get(ebid->ebi->smc.regmap, conf->cs,
  88                                &conf->smcconf);
  89 }
  90
  91 static const struct atmel_smc_timing_xlate timings_xlate_table[] = {
  92         ATMEL_SMC_SETUP_XLATE("atmel,smc-ncs-rd-setup-ns",
  93                               ATMEL_SMC_NCS_RD_SHIFT),
  94         ATMEL_SMC_SETUP_XLATE("atmel,smc-ncs-wr-setup-ns",
  95                               ATMEL_SMC_NCS_WR_SHIFT),
  96         ATMEL_SMC_SETUP_XLATE("atmel,smc-nrd-setup-ns", ATMEL_SMC_NRD_SHIFT),
  97         ATMEL_SMC_SETUP_XLATE("atmel,smc-nwe-setup-ns", ATMEL_SMC_NWE_SHIFT),
  98         ATMEL_SMC_PULSE_XLATE("atmel,smc-ncs-rd-pulse-ns",
  99                               ATMEL_SMC_NCS_RD_SHIFT),
 100         ATMEL_SMC_PULSE_XLATE("atmel,smc-ncs-wr-pulse-ns",
 101                               ATMEL_SMC_NCS_WR_SHIFT),
 102         ATMEL_SMC_PULSE_XLATE("atmel,smc-nrd-pulse-ns", ATMEL_SMC_NRD_SHIFT),
 103         ATMEL_SMC_PULSE_XLATE("atmel,smc-nwe-pulse-ns", ATMEL_SMC_NWE_SHIFT),
 104         ATMEL_SMC_CYCLE_XLATE("atmel,smc-nrd-cycle-ns", ATMEL_SMC_NRD_SHIFT),
 105         ATMEL_SMC_CYCLE_XLATE("atmel,smc-nwe-cycle-ns", ATMEL_SMC_NWE_SHIFT),
 106 };
 107
 108 static int atmel_ebi_xslate_smc_timings(struct atmel_ebi_dev *ebid,
 109                                         struct device_node *np,
 110                                         struct atmel_smc_cs_conf *smcconf)
 111 {
 112         unsigned int clk_rate = clk_get_rate(ebid->ebi->clk);
 113         unsigned int clk_period_ns = NSEC_PER_SEC / clk_rate;
 114         bool required = false;
 115         unsigned int ncycles;
 116         int ret, i;
 117         u32 val;
 118
 119         ret = of_property_read_u32(np, "atmel,smc-tdf-ns", &val);
 120         if (!ret) {
 121                 required = true;
 122                 ncycles = DIV_ROUND_UP(val, clk_period_ns);
 123                 if (ncycles > ATMEL_SMC_MODE_TDF_MAX) {
 124                         ret = -EINVAL;
 125                         goto out;
 126                 }
 127
 128                 if (ncycles < ATMEL_SMC_MODE_TDF_MIN)
 129                         ncycles = ATMEL_SMC_MODE_TDF_MIN;
 130
 131                 smcconf->mode |= ATMEL_SMC_MODE_TDF(ncycles);
 132         }
 133
 134         for (i = 0; i < ARRAY_SIZE(timings_xlate_table); i++) {
 135                 const struct atmel_smc_timing_xlate *xlate;
 136
 137                 xlate = &timings_xlate_table[i];
 138
 139                 ret = of_property_read_u32(np, xlate->name, &val);
 140                 if (ret) {
 141                         if (!required)
 142                                 continue;
 143                         else
 144                                 break;
 145                 }
 146
 147                 if (!required) {
 148                         ret = -EINVAL;
 149                         break;
 150                 }
 151
 152                 ncycles = DIV_ROUND_UP(val, clk_period_ns);
 153                 ret = xlate->converter(smcconf, xlate->shift, ncycles);
 154                 if (ret)
 155                         goto out;
 156         }
 157
 158 out:
 159         if (ret) {
 160                 dev_err(ebid->ebi->dev,
 161                         "missing or invalid timings definition in %s",
 162                         np->full_name);
 163                 return ret;
 164         }
 165
 166         return required;
 167 }
 168
 169 static int atmel_ebi_xslate_smc_config(struct atmel_ebi_dev *ebid,
 170                                        struct device_node *np,
 171                                        struct atmel_ebi_dev_config *conf)
 172 {
 173         struct atmel_smc_cs_conf *smcconf = &conf->smcconf;
 174         bool required = false;
 175         const char *tmp_str;
 176         u32 tmp;
 177         int ret;
 178
 179         ret = of_property_read_u32(np, "atmel,smc-bus-width", &tmp);
 180         if (!ret) {
 181                 switch (tmp) {
 182                 case 8:
 183                         smcconf->mode |= ATMEL_SMC_MODE_DBW_8;
 184                         break;
 185
 186                 case 16:
 187                         smcconf->mode |= ATMEL_SMC_MODE_DBW_16;
 188                         break;
 189
 190                 case 32:
 191                         smcconf->mode |= ATMEL_SMC_MODE_DBW_32;
 192                         break;
 193
 194                 default:
 195                         return -EINVAL;
 196                 }
 197
 198                 required = true;
 199         }
 200
 201         if (of_property_read_bool(np, "atmel,smc-tdf-optimized")) {
 202                 smcconf->mode |= ATMEL_SMC_MODE_TDFMODE_OPTIMIZED;
 203                 required = true;
 204         }
 205
 206         tmp_str = NULL;
 207         of_property_read_string(np, "atmel,smc-byte-access-type", &tmp_str);
 208         if (tmp_str && !strcmp(tmp_str, "write")) {
 209                 smcconf->mode |= ATMEL_SMC_MODE_BAT_WRITE;
 210                 required = true;
 211         }
 212
 213         tmp_str = NULL;
 214         of_property_read_string(np, "atmel,smc-read-mode", &tmp_str);
 215         if (tmp_str && !strcmp(tmp_str, "nrd")) {
 216                 smcconf->mode |= ATMEL_SMC_MODE_READMODE_NRD;
 217                 required = true;
 218         }
 219
 220         tmp_str = NULL;
 221         of_property_read_string(np, "atmel,smc-write-mode", &tmp_str);
 222         if (tmp_str && !strcmp(tmp_str, "nwe")) {
 223                 smcconf->mode |= ATMEL_SMC_MODE_WRITEMODE_NWE;
 224                 required = true;
 225         }
 226
 227         tmp_str = NULL;
 228         of_property_read_string(np, "atmel,smc-exnw-mode", &tmp_str);
 229         if (tmp_str) {
 230                 if (!strcmp(tmp_str, "frozen"))
 231                         smcconf->mode |= ATMEL_SMC_MODE_EXNWMODE_FROZEN;
 232                 else if (!strcmp(tmp_str, "ready"))
 233                         smcconf->mode |= ATMEL_SMC_MODE_EXNWMODE_READY;
 234                 else if (strcmp(tmp_str, "disabled"))
 235                         return -EINVAL;
 236
 237                 required = true;
 238         }
 239
 240         ret = of_property_read_u32(np, "atmel,smc-page-mode", &tmp);
 241         if (!ret) {
 242                 switch (tmp) {
 243                 case 4:
 244                         smcconf->mode |= ATMEL_SMC_MODE_PS_4;
 245                         break;
 246
 247                 case 8:
 248                         smcconf->mode |= ATMEL_SMC_MODE_PS_8;
 249                         break;
 250
 251                 case 16:
 252                         smcconf->mode |= ATMEL_SMC_MODE_PS_16;
 253                         break;
 254
 255                 case 32:
 256                         smcconf->mode |= ATMEL_SMC_MODE_PS_32;
 257                         break;
 258
 259                 default:
 260                         return -EINVAL;
 261                 }
 262
 263                 smcconf->mode |= ATMEL_SMC_MODE_PMEN;
 264                 required = true;
 265         }
 266
 267         ret = atmel_ebi_xslate_smc_timings(ebid, np, &conf->smcconf);
 268         if (ret < 0)
 269                 return -EINVAL;
 270
 271         if ((ret > 0 && !required) || (!ret && required)) {
 272                 dev_err(ebid->ebi->dev, "missing atmel,smc- properties in %s",
 273                         np->full_name);
 274                 return -EINVAL;
 275         }
 276
 277         return required;
 278 }
 279
 280 static void at91sam9_ebi_apply_config(struct atmel_ebi_dev *ebid,
 281                                       struct atmel_ebi_dev_config *conf)
 282 {
 283         atmel_smc_cs_conf_apply(ebid->ebi->smc.regmap, conf->cs,
 284                                 &conf->smcconf);
 285 }
 286
 287 static void sama5_ebi_apply_config(struct atmel_ebi_dev *ebid,
 288                                    struct atmel_ebi_dev_config *conf)
 289 {
 290         atmel_hsmc_cs_conf_apply(ebid->ebi->smc.regmap, conf->cs,
 291                                  &conf->smcconf);
 292 }
 293
 294 static int atmel_ebi_dev_setup(struct atmel_ebi *ebi, struct device_node *np,
 295                                int reg_cells)
 296 {
 297         const struct atmel_ebi_caps *caps = ebi->caps;
 298         struct atmel_ebi_dev_config conf = { };
 299         struct device *dev = ebi->dev;
 300         struct atmel_ebi_dev *ebid;
 301         unsigned long cslines = 0;
 302         int ret, numcs = 0, nentries, i;
 303         bool apply = false;
 304         u32 cs;
 305
 306         nentries = of_property_count_elems_of_size(np, "reg",
 307                                                    reg_cells * sizeof(u32));
 308         for (i = 0; i < nentries; i++) {
 309                 ret = of_property_read_u32_index(np, "reg", i * reg_cells,
 310                                                  &cs);
 311                 if (ret)
 312                         return ret;
 313
 314                 if (cs >= AT91_MATRIX_EBI_NUM_CS ||
 315                     !(ebi->caps->available_cs & BIT(cs))) {
 316                         dev_err(dev, "invalid reg property in %s\n",
 317                                 np->full_name);
 318                         return -EINVAL;
 319                 }
 320
 321                 if (!test_and_set_bit(cs, &cslines))
 322                         numcs++;
 323         }
 324
 325         if (!numcs) {
 326                 dev_err(dev, "invalid reg property in %s\n", np->full_name);
 327                 return -EINVAL;
 328         }
 329
 330         ebid = devm_kzalloc(ebi->dev,
 331                             sizeof(*ebid) + (numcs * sizeof(*ebid->configs)),
 332                             GFP_KERNEL);
 333         if (!ebid)
 334                 return -ENOMEM;
 335
 336         ebid->ebi = ebi;
 337         ebid->numcs = numcs;
 338
 339         ret = caps->xlate_config(ebid, np, &conf);
 340         if (ret < 0)
 341                 return ret;
 342         else if (ret)
 343                 apply = true;
 344
 345         i = 0;
 346         for_each_set_bit(cs, &cslines, AT91_MATRIX_EBI_NUM_CS) {
 347                 ebid->configs[i].cs = cs;
 348
 349                 if (apply) {
 350                         conf.cs = cs;
 351                         caps->apply_config(ebid, &conf);
 352                 }
 353
 354                 caps->get_config(ebid, &ebid->configs[i]);
 355
 356                 /*
 357                  * Attach the EBI device to the generic SMC logic if at least
 358                  * one "atmel,smc-" property is present.
 359                  */
 360                 if (ebi->caps->ebi_csa_offs && apply)
 361                         regmap_update_bits(ebi->matrix,
 362                                            ebi->caps->ebi_csa_offs,
 363                                            BIT(cs), 0);
 364
 365                 i++;
 366         }
 367
 368         list_add_tail(&ebid->node, &ebi->devs);
 369
 370         return 0;
 371 }
 372
 373 static const struct atmel_ebi_caps at91sam9260_ebi_caps = {
 374         .available_cs = 0xff,
 375         .ebi_csa_offs = AT91SAM9260_MATRIX_EBICSA,
 376         .get_config = at91sam9_ebi_get_config,
 377         .xlate_config = atmel_ebi_xslate_smc_config,
 378         .apply_config = at91sam9_ebi_apply_config,
 379 };
 380
 381 static const struct atmel_ebi_caps at91sam9261_ebi_caps = {
 382         .available_cs = 0xff,
 383         .ebi_csa_offs = AT91SAM9261_MATRIX_EBICSA,
 384         .get_config = at91sam9_ebi_get_config,
 385         .xlate_config = atmel_ebi_xslate_smc_config,
 386         .apply_config = at91sam9_ebi_apply_config,
 387 };
 388
 389 static const struct atmel_ebi_caps at91sam9263_ebi0_caps = {
 390         .available_cs = 0x3f,
 391         .ebi_csa_offs = AT91SAM9263_MATRIX_EBI0CSA,
 392         .get_config = at91sam9_ebi_get_config,
 393         .xlate_config = atmel_ebi_xslate_smc_config,
 394         .apply_config = at91sam9_ebi_apply_config,
 395 };
 396
 397 static const struct atmel_ebi_caps at91sam9263_ebi1_caps = {
 398         .available_cs = 0x7,
 399         .ebi_csa_offs = AT91SAM9263_MATRIX_EBI1CSA,
 400         .get_config = at91sam9_ebi_get_config,
 401         .xlate_config = atmel_ebi_xslate_smc_config,
 402         .apply_config = at91sam9_ebi_apply_config,
 403 };
 404
 405 static const struct atmel_ebi_caps at91sam9rl_ebi_caps = {
 406         .available_cs = 0x3f,
 407         .ebi_csa_offs = AT91SAM9RL_MATRIX_EBICSA,
 408         .get_config = at91sam9_ebi_get_config,
 409         .xlate_config = atmel_ebi_xslate_smc_config,
 410         .apply_config = at91sam9_ebi_apply_config,
 411 };
 412
 413 static const struct atmel_ebi_caps at91sam9g45_ebi_caps = {
 414         .available_cs = 0x3f,
 415         .ebi_csa_offs = AT91SAM9G45_MATRIX_EBICSA,
 416         .get_config = at91sam9_ebi_get_config,
 417         .xlate_config = atmel_ebi_xslate_smc_config,
 418         .apply_config = at91sam9_ebi_apply_config,
 419 };
 420
 421 static const struct atmel_ebi_caps at91sam9x5_ebi_caps = {
 422         .available_cs = 0x3f,
 423         .ebi_csa_offs = AT91SAM9X5_MATRIX_EBICSA,
 424         .get_config = at91sam9_ebi_get_config,
 425         .xlate_config = atmel_ebi_xslate_smc_config,
 426         .apply_config = at91sam9_ebi_apply_config,
 427 };
 428
 429 static const struct atmel_ebi_caps sama5d3_ebi_caps = {
 430         .available_cs = 0xf,
 431         .get_config = sama5_ebi_get_config,
 432         .xlate_config = atmel_ebi_xslate_smc_config,
 433         .apply_config = sama5_ebi_apply_config,
 434 };
 435
 436 static const struct of_device_id atmel_ebi_id_table[] = {
 437         {
 438                 .compatible = "atmel,at91sam9260-ebi",
 439                 .data = &at91sam9260_ebi_caps,
 440         },
 441         {
 442                 .compatible = "atmel,at91sam9261-ebi",
 443                 .data = &at91sam9261_ebi_caps,
 444         },
 445         {
 446                 .compatible = "atmel,at91sam9263-ebi0",
 447                 .data = &at91sam9263_ebi0_caps,
 448         },
 449         {
 450                 .compatible = "atmel,at91sam9263-ebi1",
 451                 .data = &at91sam9263_ebi1_caps,
 452         },
 453         {
 454                 .compatible = "atmel,at91sam9rl-ebi",
 455                 .data = &at91sam9rl_ebi_caps,
 456         },
 457         {
 458                 .compatible = "atmel,at91sam9g45-ebi",
 459                 .data = &at91sam9g45_ebi_caps,
 460         },
 461         {
 462                 .compatible = "atmel,at91sam9x5-ebi",
 463                 .data = &at91sam9x5_ebi_caps,
 464         },
 465         {
 466                 .compatible = "atmel,sama5d3-ebi",
 467                 .data = &sama5d3_ebi_caps,
 468         },
 469         { /* sentinel */ }
 470 };
 471
 472 static int atmel_ebi_dev_disable(struct atmel_ebi *ebi, struct device_node *np)
 473 {
 474         struct device *dev = ebi->dev;
 475         struct property *newprop;
 476
 477         newprop = devm_kzalloc(dev, sizeof(*newprop), GFP_KERNEL);
 478         if (!newprop)
 479                 return -ENOMEM;
 480
 481         newprop->name = devm_kstrdup(dev, "status", GFP_KERNEL);
 482         if (!newprop->name)
 483                 return -ENOMEM;
 484
 485         newprop->value = devm_kstrdup(dev, "disabled", GFP_KERNEL);
 486         if (!newprop->value)
 487                 return -ENOMEM;
 488
 489         newprop->length = sizeof("disabled");
 490
 491         return of_update_property(np, newprop);
 492 }
 493
 494 static int atmel_ebi_probe(struct platform_device *pdev)
 495 {
 496         struct device *dev = &pdev->dev;
 497         struct device_node *child, *np = dev->of_node, *smc_np;
 498         const struct of_device_id *match;
 499         struct atmel_ebi *ebi;
 500         int ret, reg_cells;
 501         struct clk *clk;
 502         u32 val;
 503
 504         match = of_match_device(atmel_ebi_id_table, dev);
 505         if (!match || !match->data)
 506                 return -EINVAL;
 507
 508         ebi = devm_kzalloc(dev, sizeof(*ebi), GFP_KERNEL);
 509         if (!ebi)
 510                 return -ENOMEM;
 511
 512         platform_set_drvdata(pdev, ebi);
 513
 514         INIT_LIST_HEAD(&ebi->devs);
 515         ebi->caps = match->data;
 516         ebi->dev = dev;
 517
 518         clk = devm_clk_get(dev, NULL);
 519         if (IS_ERR(clk))
 520                 return PTR_ERR(clk);
 521
 522         ebi->clk = clk;
 523
 524         smc_np = of_parse_phandle(dev->of_node, "atmel,smc", 0);
 525
 526         ebi->smc.regmap = syscon_node_to_regmap(smc_np);
 527         if (IS_ERR(ebi->smc.regmap))
 528                 return PTR_ERR(ebi->smc.regmap);
 529
 530         ebi->smc.clk = of_clk_get(smc_np, 0);
 531         if (IS_ERR(ebi->smc.clk)) {
 532                 if (PTR_ERR(ebi->smc.clk) != -ENOENT)
 533                         return PTR_ERR(ebi->smc.clk);
 534
 535                 ebi->smc.clk = NULL;
 536         }
 537         ret = clk_prepare_enable(ebi->smc.clk);
 538         if (ret)
 539                 return ret;
 540
 541         /*
 542          * The sama5d3 does not provide an EBICSA register and thus does need
 543          * to access the matrix registers.
 544          */
 545         if (ebi->caps->ebi_csa_offs) {
 546                 ebi->matrix =
 547                         syscon_regmap_lookup_by_phandle(np, "atmel,matrix");
 548                 if (IS_ERR(ebi->matrix))
 549                         return PTR_ERR(ebi->matrix);
 550         }
 551
 552         ret = of_property_read_u32(np, "#address-cells", &val);
 553         if (ret) {
 554                 dev_err(dev, "missing #address-cells property\n");
 555                 return ret;
 556         }
 557
 558         reg_cells = val;
 559
 560         ret = of_property_read_u32(np, "#size-cells", &val);
 561         if (ret) {
 562                 dev_err(dev, "missing #address-cells property\n");
 563                 return ret;
 564         }
 565
 566         reg_cells += val;
 567
 568         for_each_available_child_of_node(np, child) {
 569                 if (!of_find_property(child, "reg", NULL))
 570                         continue;
 571
 572                 ret = atmel_ebi_dev_setup(ebi, child, reg_cells);
 573                 if (ret) {
 574                         dev_err(dev, "failed to configure EBI bus for %s, disabling the device",
 575                                 child->full_name);
 576
 577                         ret = atmel_ebi_dev_disable(ebi, child);
 578                         if (ret)
 579                                 return ret;
 580                 }
 581         }
 582
 583         return of_platform_populate(np, NULL, NULL, dev);
 584 }
 585
 586 static __maybe_unused int atmel_ebi_resume(struct device *dev)
 587 {
 588         struct atmel_ebi *ebi = dev_get_drvdata(dev);
 589         struct atmel_ebi_dev *ebid;
 590
 591         list_for_each_entry(ebid, &ebi->devs, node) {
 592                 int i;
 593
 594                 for (i = 0; i < ebid->numcs; i++)
 595                         ebid->ebi->caps->apply_config(ebid, &ebid->configs[i]);
 596         }
 597
 598         return 0;
 599 }
 600
 601 static SIMPLE_DEV_PM_OPS(atmel_ebi_pm_ops, NULL, atmel_ebi_resume);
 602
 603 static struct platform_driver atmel_ebi_driver = {
 604         .driver = {
 605                 .name = "atmel-ebi",
 606                 .of_match_table = atmel_ebi_id_table,
 607                 .pm = &atmel_ebi_pm_ops,
 608         },
 609 };
 610 builtin_platform_driver_probe(atmel_ebi_driver, atmel_ebi_probe);