drivers/bus/ti-sysc.c

   1 /*
   2  * ti-sysc.c - Texas Instruments sysc interconnect target driver
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
   9  * kind, whether express or implied; without even the implied warranty
  10  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <linux/io.h>
  15 #include <linux/clk.h>
  16 #include <linux/module.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/pm_runtime.h>
  19 #include <linux/of_address.h>
  20 #include <linux/of_platform.h>
  21
  22 enum sysc_registers {
  23         SYSC_REVISION,
  24         SYSC_SYSCONFIG,
  25         SYSC_SYSSTATUS,
  26         SYSC_MAX_REGS,
  27 };
  28
  29 static const char * const reg_names[] = { "rev", "sysc", "syss", };
  30
  31 enum sysc_clocks {
  32         SYSC_FCK,
  33         SYSC_ICK,
  34         SYSC_MAX_CLOCKS,
  35 };
  36
  37 static const char * const clock_names[] = { "fck", "ick", };
  38
  39 /**
  40  * struct sysc - TI sysc interconnect target module registers and capabilities
  41  * @dev: struct device pointer
  42  * @module_pa: physical address of the interconnect target module
  43  * @module_size: size of the interconnect target module
  44  * @module_va: virtual address of the interconnect target module
  45  * @offsets: register offsets from module base
  46  * @clocks: clocks used by the interconnect target module
  47  * @legacy_mode: configured for legacy mode if set
  48  */
  49 struct sysc {
  50         struct device *dev;
  51         u64 module_pa;
  52         u32 module_size;
  53         void __iomem *module_va;
  54         int offsets[SYSC_MAX_REGS];
  55         struct clk *clocks[SYSC_MAX_CLOCKS];
  56         const char *legacy_mode;
  57 };
  58
  59 static u32 sysc_read_revision(struct sysc *ddata)
  60 {
  61         return readl_relaxed(ddata->module_va +
  62                              ddata->offsets[SYSC_REVISION]);
  63 }
  64
  65 static int sysc_get_one_clock(struct sysc *ddata,
  66                               enum sysc_clocks index)
  67 {
  68         const char *name;
  69         int error;
  70
  71         switch (index) {
  72         case SYSC_FCK:
  73                 break;
  74         case SYSC_ICK:
  75                 break;
  76         default:
  77                 return -EINVAL;
  78         }
  79         name = clock_names[index];
  80
  81         ddata->clocks[index] = devm_clk_get(ddata->dev, name);
  82         if (IS_ERR(ddata->clocks[index])) {
  83                 if (PTR_ERR(ddata->clocks[index]) == -ENOENT)
  84                         return 0;
  85
  86                 dev_err(ddata->dev, "clock get error for %s: %li\n",
  87                         name, PTR_ERR(ddata->clocks[index]));
  88
  89                 return PTR_ERR(ddata->clocks[index]);
  90         }
  91
  92         error = clk_prepare(ddata->clocks[index]);
  93         if (error) {
  94                 dev_err(ddata->dev, "clock prepare error for %s: %i\n",
  95                         name, error);
  96
  97                 return error;
  98         }
  99
 100         return 0;
 101 }
 102
 103 static int sysc_get_clocks(struct sysc *ddata)
 104 {
 105         int i, error;
 106
 107         if (ddata->legacy_mode)
 108                 return 0;
 109
 110         for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 111                 error = sysc_get_one_clock(ddata, i);
 112                 if (error && error != -ENOENT)
 113                         return error;
 114         }
 115
 116         return 0;
 117 }
 118
 119 /**
 120  * sysc_parse_and_check_child_range - parses module IO region from ranges
 121  * @ddata: device driver data
 122  *
 123  * In general we only need rev, syss, and sysc registers and not the whole
 124  * module range. But we do want the offsets for these registers from the
 125  * module base. This allows us to check them against the legacy hwmod
 126  * platform data. Let's also check the ranges are configured properly.
 127  */
 128 static int sysc_parse_and_check_child_range(struct sysc *ddata)
 129 {
 130         struct device_node *np = ddata->dev->of_node;
 131         const __be32 *ranges;
 132         u32 nr_addr, nr_size;
 133         int len, error;
 134
 135         ranges = of_get_property(np, "ranges", &len);
 136         if (!ranges) {
 137                 dev_err(ddata->dev, "missing ranges for %pOF\n", np);
 138
 139                 return -ENOENT;
 140         }
 141
 142         len /= sizeof(*ranges);
 143
 144         if (len < 3) {
 145                 dev_err(ddata->dev, "incomplete ranges for %pOF\n", np);
 146
 147                 return -EINVAL;
 148         }
 149
 150         error = of_property_read_u32(np, "#address-cells", &nr_addr);
 151         if (error)
 152                 return -ENOENT;
 153
 154         error = of_property_read_u32(np, "#size-cells", &nr_size);
 155         if (error)
 156                 return -ENOENT;
 157
 158         if (nr_addr != 1 || nr_size != 1) {
 159                 dev_err(ddata->dev, "invalid ranges for %pOF\n", np);
 160
 161                 return -EINVAL;
 162         }
 163
 164         ranges++;
 165         ddata->module_pa = of_translate_address(np, ranges++);
 166         ddata->module_size = be32_to_cpup(ranges);
 167
 168         dev_dbg(ddata->dev, "interconnect target 0x%llx size 0x%x for %pOF\n",
 169                 ddata->module_pa, ddata->module_size, np);
 170
 171         return 0;
 172 }
 173
 174 /**
 175  * sysc_check_one_child - check child configuration
 176  * @ddata: device driver data
 177  * @np: child device node
 178  *
 179  * Let's avoid messy situations where we have new interconnect target
 180  * node but children have "ti,hwmods". These belong to the interconnect
 181  * target node and are managed by this driver.
 182  */
 183 static int sysc_check_one_child(struct sysc *ddata,
 184                                 struct device_node *np)
 185 {
 186         const char *name;
 187
 188         name = of_get_property(np, "ti,hwmods", NULL);
 189         if (name)
 190                 dev_warn(ddata->dev, "really a child ti,hwmods property?");
 191
 192         return 0;
 193 }
 194
 195 static int sysc_check_children(struct sysc *ddata)
 196 {
 197         struct device_node *child;
 198         int error;
 199
 200         for_each_child_of_node(ddata->dev->of_node, child) {
 201                 error = sysc_check_one_child(ddata, child);
 202                 if (error)
 203                         return error;
 204         }
 205
 206         return 0;
 207 }
 208
 209 /**
 210  * sysc_parse_one - parses the interconnect target module registers
 211  * @ddata: device driver data
 212  * @reg: register to parse
 213  */
 214 static int sysc_parse_one(struct sysc *ddata, enum sysc_registers reg)
 215 {
 216         struct resource *res;
 217         const char *name;
 218
 219         switch (reg) {
 220         case SYSC_REVISION:
 221         case SYSC_SYSCONFIG:
 222         case SYSC_SYSSTATUS:
 223                 name = reg_names[reg];
 224                 break;
 225         default:
 226                 return -EINVAL;
 227         }
 228
 229         res = platform_get_resource_byname(to_platform_device(ddata->dev),
 230                                            IORESOURCE_MEM, name);
 231         if (!res) {
 232                 dev_dbg(ddata->dev, "has no %s register\n", name);
 233                 ddata->offsets[reg] = -ENODEV;
 234
 235                 return 0;
 236         }
 237
 238         ddata->offsets[reg] = res->start - ddata->module_pa;
 239
 240         return 0;
 241 }
 242
 243 static int sysc_parse_registers(struct sysc *ddata)
 244 {
 245         int i, error;
 246
 247         for (i = 0; i < SYSC_MAX_REGS; i++) {
 248                 error = sysc_parse_one(ddata, i);
 249                 if (error)
 250                         return error;
 251         }
 252
 253         return 0;
 254 }
 255
 256 /**
 257  * sysc_check_registers - check for misconfigured register overlaps
 258  * @ddata: device driver data
 259  */
 260 static int sysc_check_registers(struct sysc *ddata)
 261 {
 262         int i, j, nr_regs = 0, nr_matches = 0;
 263
 264         for (i = 0; i < SYSC_MAX_REGS; i++) {
 265                 if (ddata->offsets[i] < 0)
 266                         continue;
 267
 268                 if (ddata->offsets[i] > (ddata->module_size - 4)) {
 269                         dev_err(ddata->dev, "register outside module range");
 270
 271                                 return -EINVAL;
 272                 }
 273
 274                 for (j = 0; j < SYSC_MAX_REGS; j++) {
 275                         if (ddata->offsets[j] < 0)
 276                                 continue;
 277
 278                         if (ddata->offsets[i] == ddata->offsets[j])
 279                                 nr_matches++;
 280                 }
 281                 nr_regs++;
 282         }
 283
 284         if (nr_regs < 1) {
 285                 dev_err(ddata->dev, "missing registers\n");
 286
 287                 return -EINVAL;
 288         }
 289
 290         if (nr_matches > nr_regs) {
 291                 dev_err(ddata->dev, "overlapping registers: (%i/%i)",
 292                         nr_regs, nr_matches);
 293
 294                 return -EINVAL;
 295         }
 296
 297         return 0;
 298 }
 299
 300 /**
 301  * syc_ioremap - ioremap register space for the interconnect target module
 302  * @ddata: deviec driver data
 303  *
 304  * Note that the interconnect target module registers can be anywhere
 305  * within the first child device address space. For example, SGX has
 306  * them at offset 0x1fc00 in the 32MB module address space. We just
 307  * what we need around the interconnect target module registers.
 308  */
 309 static int sysc_ioremap(struct sysc *ddata)
 310 {
 311         u32 size = 0;
 312
 313         if (ddata->offsets[SYSC_SYSSTATUS] >= 0)
 314                 size = ddata->offsets[SYSC_SYSSTATUS];
 315         else if (ddata->offsets[SYSC_SYSCONFIG] >= 0)
 316                 size = ddata->offsets[SYSC_SYSCONFIG];
 317         else if (ddata->offsets[SYSC_REVISION] >= 0)
 318                 size = ddata->offsets[SYSC_REVISION];
 319         else
 320                 return -EINVAL;
 321
 322         size &= 0xfff00;
 323         size += SZ_256;
 324
 325         ddata->module_va = devm_ioremap(ddata->dev,
 326                                         ddata->module_pa,
 327                                         size);
 328         if (!ddata->module_va)
 329                 return -EIO;
 330
 331         return 0;
 332 }
 333
 334 /**
 335  * sysc_map_and_check_registers - ioremap and check device registers
 336  * @ddata: device driver data
 337  */
 338 static int sysc_map_and_check_registers(struct sysc *ddata)
 339 {
 340         int error;
 341
 342         error = sysc_parse_and_check_child_range(ddata);
 343         if (error)
 344                 return error;
 345
 346         error = sysc_check_children(ddata);
 347         if (error)
 348                 return error;
 349
 350         error = sysc_parse_registers(ddata);
 351         if (error)
 352                 return error;
 353
 354         error = sysc_ioremap(ddata);
 355         if (error)
 356                 return error;
 357
 358         error = sysc_check_registers(ddata);
 359         if (error)
 360                 return error;
 361
 362         return 0;
 363 }
 364
 365 /**
 366  * sysc_show_rev - read and show interconnect target module revision
 367  * @bufp: buffer to print the information to
 368  * @ddata: device driver data
 369  */
 370 static int sysc_show_rev(char *bufp, struct sysc *ddata)
 371 {
 372         int error, len;
 373
 374         if (ddata->offsets[SYSC_REVISION] < 0)
 375                 return sprintf(bufp, ":NA");
 376
 377         error = pm_runtime_get_sync(ddata->dev);
 378         if (error < 0) {
 379                 pm_runtime_put_noidle(ddata->dev);
 380
 381                 return 0;
 382         }
 383
 384         len = sprintf(bufp, ":%08x", sysc_read_revision(ddata));
 385
 386         pm_runtime_mark_last_busy(ddata->dev);
 387         pm_runtime_put_autosuspend(ddata->dev);
 388
 389         return len;
 390 }
 391
 392 static int sysc_show_reg(struct sysc *ddata,
 393                          char *bufp, enum sysc_registers reg)
 394 {
 395         if (ddata->offsets[reg] < 0)
 396                 return sprintf(bufp, ":NA");
 397
 398         return sprintf(bufp, ":%x", ddata->offsets[reg]);
 399 }
 400
 401 /**
 402  * sysc_show_registers - show information about interconnect target module
 403  * @ddata: device driver data
 404  */
 405 static void sysc_show_registers(struct sysc *ddata)
 406 {
 407         char buf[128];
 408         char *bufp = buf;
 409         int i;
 410
 411         for (i = 0; i < SYSC_MAX_REGS; i++)
 412                 bufp += sysc_show_reg(ddata, bufp, i);
 413
 414         bufp += sysc_show_rev(bufp, ddata);
 415
 416         dev_dbg(ddata->dev, "%llx:%x%s\n",
 417                 ddata->module_pa, ddata->module_size,
 418                 buf);
 419 }
 420
 421 static int __maybe_unused sysc_runtime_suspend(struct device *dev)
 422 {
 423         struct sysc *ddata;
 424         int i;
 425
 426         ddata = dev_get_drvdata(dev);
 427
 428         if (ddata->legacy_mode)
 429                 return 0;
 430
 431         for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 432                 if (IS_ERR_OR_NULL(ddata->clocks[i]))
 433                         continue;
 434                 clk_disable(ddata->clocks[i]);
 435         }
 436
 437         return 0;
 438 }
 439
 440 static int __maybe_unused sysc_runtime_resume(struct device *dev)
 441 {
 442         struct sysc *ddata;
 443         int i, error;
 444
 445         ddata = dev_get_drvdata(dev);
 446
 447         if (ddata->legacy_mode)
 448                 return 0;
 449
 450         for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 451                 if (IS_ERR_OR_NULL(ddata->clocks[i]))
 452                         continue;
 453                 error = clk_enable(ddata->clocks[i]);
 454                 if (error)
 455                         return error;
 456         }
 457
 458         return 0;
 459 }
 460
 461 static const struct dev_pm_ops sysc_pm_ops = {
 462         SET_RUNTIME_PM_OPS(sysc_runtime_suspend,
 463                            sysc_runtime_resume,
 464                            NULL)
 465 };
 466
 467 static void sysc_unprepare(struct sysc *ddata)
 468 {
 469         int i;
 470
 471         for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 472                 if (!IS_ERR_OR_NULL(ddata->clocks[i]))
 473                         clk_unprepare(ddata->clocks[i]);
 474         }
 475 }
 476
 477 static int sysc_probe(struct platform_device *pdev)
 478 {
 479         struct device_node *np = pdev->dev.of_node;
 480         struct sysc *ddata;
 481         int error;
 482
 483         ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
 484         if (!ddata)
 485                 return -ENOMEM;
 486
 487         ddata->dev = &pdev->dev;
 488         ddata->legacy_mode = of_get_property(np, "ti,hwmods", NULL);
 489
 490         error = sysc_get_clocks(ddata);
 491         if (error)
 492                 return error;
 493
 494         error = sysc_map_and_check_registers(ddata);
 495         if (error)
 496                 goto unprepare;
 497
 498         platform_set_drvdata(pdev, ddata);
 499
 500         pm_runtime_enable(ddata->dev);
 501         error = pm_runtime_get_sync(ddata->dev);
 502         if (error < 0) {
 503                 pm_runtime_put_noidle(ddata->dev);
 504                 pm_runtime_disable(ddata->dev);
 505                 goto unprepare;
 506         }
 507
 508         pm_runtime_use_autosuspend(ddata->dev);
 509
 510         sysc_show_registers(ddata);
 511
 512         error = of_platform_populate(ddata->dev->of_node,
 513                                      NULL, NULL, ddata->dev);
 514         if (error)
 515                 goto err;
 516
 517         pm_runtime_mark_last_busy(ddata->dev);
 518         pm_runtime_put_autosuspend(ddata->dev);
 519
 520         return 0;
 521
 522 err:
 523         pm_runtime_dont_use_autosuspend(&pdev->dev);
 524         pm_runtime_put_sync(&pdev->dev);
 525         pm_runtime_disable(&pdev->dev);
 526 unprepare:
 527         sysc_unprepare(ddata);
 528
 529         return error;
 530 }
 531
 532 static int sysc_remove(struct platform_device *pdev)
 533 {
 534         struct sysc *ddata = platform_get_drvdata(pdev);
 535         int error;
 536
 537         error = pm_runtime_get_sync(ddata->dev);
 538         if (error < 0) {
 539                 pm_runtime_put_noidle(ddata->dev);
 540                 pm_runtime_disable(ddata->dev);
 541                 goto unprepare;
 542         }
 543
 544         of_platform_depopulate(&pdev->dev);
 545
 546         pm_runtime_dont_use_autosuspend(&pdev->dev);
 547         pm_runtime_put_sync(&pdev->dev);
 548         pm_runtime_disable(&pdev->dev);
 549
 550 unprepare:
 551         sysc_unprepare(ddata);
 552
 553         return 0;
 554 }
 555
 556 static const struct of_device_id sysc_match[] = {
 557         { .compatible = "ti,sysc-omap2" },
 558         { .compatible = "ti,sysc-omap4" },
 559         { .compatible = "ti,sysc-omap4-simple" },
 560         { .compatible = "ti,sysc-omap3430-sr" },
 561         { .compatible = "ti,sysc-omap3630-sr" },
 562         { .compatible = "ti,sysc-omap4-sr" },
 563         { .compatible = "ti,sysc-omap3-sham" },
 564         { .compatible = "ti,sysc-omap-aes" },
 565         { .compatible = "ti,sysc-mcasp" },
 566         { .compatible = "ti,sysc-usb-host-fs" },
 567         {  },
 568 };
 569 MODULE_DEVICE_TABLE(of, sysc_match);
 570
 571 static struct platform_driver sysc_driver = {
 572         .probe          = sysc_probe,
 573         .remove         = sysc_remove,
 574         .driver         = {
 575                 .name   = "ti-sysc",
 576                 .of_match_table = sysc_match,
 577                 .pm = &sysc_pm_ops,
 578         },
 579 };
 580 module_platform_driver(sysc_driver);
 581
 582 MODULE_DESCRIPTION("TI sysc interconnect target driver");
 583 MODULE_LICENSE("GPL v2");