drivers/soc/ti/pm33xx.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * AM33XX Power Management Routines
   4  *
   5  * Copyright (C) 2012-2018 Texas Instruments Incorporated - http://www.ti.com/
   6  *      Vaibhav Bedia, Dave Gerlach
   7  */
   8
   9 #include <linux/clk.h>
  10 #include <linux/cpu.h>
  11 #include <linux/err.h>
  12 #include <linux/genalloc.h>
  13 #include <linux/kernel.h>
  14 #include <linux/init.h>
  15 #include <linux/io.h>
  16 #include <linux/module.h>
  17 #include <linux/nvmem-consumer.h>
  18 #include <linux/of.h>
  19 #include <linux/platform_data/pm33xx.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/rtc.h>
  22 #include <linux/sizes.h>
  23 #include <linux/sram.h>
  24 #include <linux/suspend.h>
  25 #include <linux/ti-emif-sram.h>
  26 #include <linux/wkup_m3_ipc.h>
  27
  28 #include <asm/proc-fns.h>
  29 #include <asm/suspend.h>
  30 #include <asm/system_misc.h>
  31
  32 #define AMX3_PM_SRAM_SYMBOL_OFFSET(sym) ((unsigned long)(sym) - \
  33                                          (unsigned long)pm_sram->do_wfi)
  34
  35 #define RTC_SCRATCH_RESUME_REG  0
  36 #define RTC_SCRATCH_MAGIC_REG   1
  37 #define RTC_REG_BOOT_MAGIC      0x8cd0 /* RTC */
  38 #define GIC_INT_SET_PENDING_BASE 0x200
  39 #define AM43XX_GIC_DIST_BASE    0x48241000
  40
  41 static u32 rtc_magic_val;
  42
  43 static int (*am33xx_do_wfi_sram)(unsigned long unused);
  44 static phys_addr_t am33xx_do_wfi_sram_phys;
  45
  46 static struct gen_pool *sram_pool, *sram_pool_data;
  47 static unsigned long ocmcram_location, ocmcram_location_data;
  48
  49 static struct rtc_device *omap_rtc;
  50 static void __iomem *gic_dist_base;
  51
  52 static struct am33xx_pm_platform_data *pm_ops;
  53 static struct am33xx_pm_sram_addr *pm_sram;
  54
  55 static struct device *pm33xx_dev;
  56 static struct wkup_m3_ipc *m3_ipc;
  57
  58 #ifdef CONFIG_SUSPEND
  59
  60 static int rtc_only_idle;
  61 static int retrigger_irq;
  62
  63 static unsigned long suspend_wfi_flags;
  64
  65 static struct wkup_m3_wakeup_src wakeup_src = {.irq_nr = 0,
  66         .src = "Unknown",
  67 };
  68
  69 static struct wkup_m3_wakeup_src rtc_alarm_wakeup = {
  70         .irq_nr = 108, .src = "RTC Alarm",
  71 };
  72
  73 static struct wkup_m3_wakeup_src rtc_ext_wakeup = {
  74         .irq_nr = 0, .src = "Ext wakeup",
  75 };
  76
  77 #endif
  78
  79 static u32 sram_suspend_address(unsigned long addr)
  80 {
  81         return ((unsigned long)am33xx_do_wfi_sram +
  82                 AMX3_PM_SRAM_SYMBOL_OFFSET(addr));
  83 }
  84
  85 static int am33xx_push_sram_idle(void)
  86 {
  87         struct am33xx_pm_ro_sram_data ro_sram_data;
  88         int ret;
  89         u32 table_addr, ro_data_addr;
  90         void *copy_addr;
  91
  92         ro_sram_data.amx3_pm_sram_data_virt = ocmcram_location_data;
  93         ro_sram_data.amx3_pm_sram_data_phys =
  94                 gen_pool_virt_to_phys(sram_pool_data, ocmcram_location_data);
  95         ro_sram_data.rtc_base_virt = pm_ops->get_rtc_base_addr();
  96
  97         /* Save physical address to calculate resume offset during pm init */
  98         am33xx_do_wfi_sram_phys = gen_pool_virt_to_phys(sram_pool,
  99                                                         ocmcram_location);
 100
 101         am33xx_do_wfi_sram = sram_exec_copy(sram_pool, (void *)ocmcram_location,
 102                                             pm_sram->do_wfi,
 103                                             *pm_sram->do_wfi_sz);
 104         if (!am33xx_do_wfi_sram) {
 105                 dev_err(pm33xx_dev,
 106                         "PM: %s: am33xx_do_wfi copy to sram failed\n",
 107                         __func__);
 108                 return -ENODEV;
 109         }
 110
 111         table_addr =
 112                 sram_suspend_address((unsigned long)pm_sram->emif_sram_table);
 113         ret = ti_emif_copy_pm_function_table(sram_pool, (void *)table_addr);
 114         if (ret) {
 115                 dev_dbg(pm33xx_dev,
 116                         "PM: %s: EMIF function copy failed\n", __func__);
 117                 return -EPROBE_DEFER;
 118         }
 119
 120         ro_data_addr =
 121                 sram_suspend_address((unsigned long)pm_sram->ro_sram_data);
 122         copy_addr = sram_exec_copy(sram_pool, (void *)ro_data_addr,
 123                                    &ro_sram_data,
 124                                    sizeof(ro_sram_data));
 125         if (!copy_addr) {
 126                 dev_err(pm33xx_dev,
 127                         "PM: %s: ro_sram_data copy to sram failed\n",
 128                         __func__);
 129                 return -ENODEV;
 130         }
 131
 132         return 0;
 133 }
 134
 135 static int __init am43xx_map_gic(void)
 136 {
 137         gic_dist_base = ioremap(AM43XX_GIC_DIST_BASE, SZ_4K);
 138
 139         if (!gic_dist_base)
 140                 return -ENOMEM;
 141
 142         return 0;
 143 }
 144
 145 #ifdef CONFIG_SUSPEND
 146
 147 static int rtc_only_idle;
 148 static int retrigger_irq;
 149
 150 struct wkup_m3_wakeup_src rtc_wake_src(void)
 151 {
 152         u32 i;
 153
 154         i = __raw_readl(pm_ops->get_rtc_base_addr() + 0x44) & 0x40;
 155
 156         if (i) {
 157                 retrigger_irq = rtc_alarm_wakeup.irq_nr;
 158                 return rtc_alarm_wakeup;
 159         }
 160
 161         retrigger_irq = rtc_ext_wakeup.irq_nr;
 162
 163         return rtc_ext_wakeup;
 164 }
 165
 166 int am33xx_rtc_only_idle(unsigned long wfi_flags)
 167 {
 168         rtc_power_off_program(omap_rtc);
 169         am33xx_do_wfi_sram(wfi_flags);
 170         return 0;
 171 }
 172
 173 static int am33xx_pm_suspend(suspend_state_t suspend_state)
 174 {
 175         int i, ret = 0;
 176
 177         if (suspend_state == PM_SUSPEND_MEM &&
 178             pm_ops->check_off_mode_enable()) {
 179                 pm_ops->prepare_rtc_suspend();
 180                 pm_ops->save_context();
 181                 suspend_wfi_flags |= WFI_FLAG_RTC_ONLY;
 182                 clk_save_context();
 183                 ret = pm_ops->soc_suspend(suspend_state, am33xx_rtc_only_idle,
 184                                           suspend_wfi_flags);
 185
 186                 suspend_wfi_flags &= ~WFI_FLAG_RTC_ONLY;
 187
 188                 if (!ret) {
 189                         clk_restore_context();
 190                         pm_ops->restore_context();
 191                         m3_ipc->ops->set_rtc_only(m3_ipc);
 192                         am33xx_push_sram_idle();
 193                 }
 194         } else {
 195                 ret = pm_ops->soc_suspend(suspend_state, am33xx_do_wfi_sram,
 196                                           suspend_wfi_flags);
 197         }
 198
 199         if (ret) {
 200                 dev_err(pm33xx_dev, "PM: Kernel suspend failure\n");
 201         } else {
 202                 i = m3_ipc->ops->request_pm_status(m3_ipc);
 203
 204                 switch (i) {
 205                 case 0:
 206                         dev_info(pm33xx_dev,
 207                                  "PM: Successfully put all powerdomains to target state\n");
 208                         break;
 209                 case 1:
 210                         dev_err(pm33xx_dev,
 211                                 "PM: Could not transition all powerdomains to target state\n");
 212                         ret = -1;
 213                         break;
 214                 default:
 215                         dev_err(pm33xx_dev,
 216                                 "PM: CM3 returned unknown result = %d\n", i);
 217                         ret = -1;
 218                 }
 219
 220                 /* print the wakeup reason */
 221                 if (rtc_only_idle) {
 222                         wakeup_src = rtc_wake_src();
 223                         pr_info("PM: Wakeup source %s\n", wakeup_src.src);
 224                 } else {
 225                         pr_info("PM: Wakeup source %s\n",
 226                                 m3_ipc->ops->request_wake_src(m3_ipc));
 227                 }
 228         }
 229
 230         if (suspend_state == PM_SUSPEND_MEM && pm_ops->check_off_mode_enable())
 231                 pm_ops->prepare_rtc_resume();
 232
 233         return ret;
 234 }
 235
 236 static int am33xx_pm_enter(suspend_state_t suspend_state)
 237 {
 238         int ret = 0;
 239
 240         switch (suspend_state) {
 241         case PM_SUSPEND_MEM:
 242         case PM_SUSPEND_STANDBY:
 243                 ret = am33xx_pm_suspend(suspend_state);
 244                 break;
 245         default:
 246                 ret = -EINVAL;
 247         }
 248
 249         return ret;
 250 }
 251
 252 static int am33xx_pm_begin(suspend_state_t state)
 253 {
 254         int ret = -EINVAL;
 255
 256         if (state == PM_SUSPEND_MEM && pm_ops->check_off_mode_enable()) {
 257                 nvmem_device_write(omap_rtc->nvmem, RTC_SCRATCH_MAGIC_REG * 4,
 258                                    4, (void *)&rtc_magic_val);
 259                 rtc_only_idle = 1;
 260         } else {
 261                 rtc_only_idle = 0;
 262         }
 263
 264         cpu_idle_poll_ctrl(true);
 265
 266         switch (state) {
 267         case PM_SUSPEND_MEM:
 268                 ret = m3_ipc->ops->prepare_low_power(m3_ipc, WKUP_M3_DEEPSLEEP);
 269                 break;
 270         case PM_SUSPEND_STANDBY:
 271                 ret = m3_ipc->ops->prepare_low_power(m3_ipc, WKUP_M3_STANDBY);
 272                 break;
 273         }
 274
 275         return ret;
 276 }
 277
 278 static void am33xx_pm_end(void)
 279 {
 280         u32 val = 0;
 281
 282         m3_ipc->ops->finish_low_power(m3_ipc);
 283         if (rtc_only_idle) {
 284                 if (retrigger_irq)
 285                         /*
 286                          * 32 bits of Interrupt Set-Pending correspond to 32
 287                          * 32 interupts. Compute the bit offset of the
 288                          * Interrupt and set that particular bit
 289                          * Compute the register offset by dividing interrupt
 290                          * number by 32 and mutiplying by 4
 291                          */
 292                         writel_relaxed(1 << (retrigger_irq & 31),
 293                                        gic_dist_base + GIC_INT_SET_PENDING_BASE
 294                                        + retrigger_irq / 32 * 4);
 295                         nvmem_device_write(omap_rtc->nvmem,
 296                                            RTC_SCRATCH_MAGIC_REG * 4,
 297                                            4, (void *)&val);
 298         }
 299
 300         rtc_only_idle = 0;
 301
 302         cpu_idle_poll_ctrl(false);
 303 }
 304
 305 static int am33xx_pm_valid(suspend_state_t state)
 306 {
 307         switch (state) {
 308         case PM_SUSPEND_STANDBY:
 309         case PM_SUSPEND_MEM:
 310                 return 1;
 311         default:
 312                 return 0;
 313         }
 314 }
 315
 316 static const struct platform_suspend_ops am33xx_pm_ops = {
 317         .begin          = am33xx_pm_begin,
 318         .end            = am33xx_pm_end,
 319         .enter          = am33xx_pm_enter,
 320         .valid          = am33xx_pm_valid,
 321 };
 322 #endif /* CONFIG_SUSPEND */
 323
 324 static void am33xx_pm_set_ipc_ops(void)
 325 {
 326         u32 resume_address;
 327         int temp;
 328
 329         temp = ti_emif_get_mem_type();
 330         if (temp < 0) {
 331                 dev_err(pm33xx_dev, "PM: Cannot determine memory type, no PM available\n");
 332                 return;
 333         }
 334         m3_ipc->ops->set_mem_type(m3_ipc, temp);
 335
 336         /* Physical resume address to be used by ROM code */
 337         resume_address = am33xx_do_wfi_sram_phys +
 338                          *pm_sram->resume_offset + 0x4;
 339
 340         m3_ipc->ops->set_resume_address(m3_ipc, (void *)resume_address);
 341 }
 342
 343 static void am33xx_pm_free_sram(void)
 344 {
 345         gen_pool_free(sram_pool, ocmcram_location, *pm_sram->do_wfi_sz);
 346         gen_pool_free(sram_pool_data, ocmcram_location_data,
 347                       sizeof(struct am33xx_pm_ro_sram_data));
 348 }
 349
 350 /*
 351  * Push the minimal suspend-resume code to SRAM
 352  */
 353 static int am33xx_pm_alloc_sram(void)
 354 {
 355         struct device_node *np;
 356         int ret = 0;
 357
 358         np = of_find_compatible_node(NULL, NULL, "ti,omap3-mpu");
 359         if (!np) {
 360                 np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu");
 361                 if (!np) {
 362                         dev_err(pm33xx_dev, "PM: %s: Unable to find device node for mpu\n",
 363                                 __func__);
 364                         return -ENODEV;
 365                 }
 366         }
 367
 368         sram_pool = of_gen_pool_get(np, "pm-sram", 0);
 369         if (!sram_pool) {
 370                 dev_err(pm33xx_dev, "PM: %s: Unable to get sram pool for ocmcram\n",
 371                         __func__);
 372                 ret = -ENODEV;
 373                 goto mpu_put_node;
 374         }
 375
 376         sram_pool_data = of_gen_pool_get(np, "pm-sram", 1);
 377         if (!sram_pool_data) {
 378                 dev_err(pm33xx_dev, "PM: %s: Unable to get sram data pool for ocmcram\n",
 379                         __func__);
 380                 ret = -ENODEV;
 381                 goto mpu_put_node;
 382         }
 383
 384         ocmcram_location = gen_pool_alloc(sram_pool, *pm_sram->do_wfi_sz);
 385         if (!ocmcram_location) {
 386                 dev_err(pm33xx_dev, "PM: %s: Unable to allocate memory from ocmcram\n",
 387                         __func__);
 388                 ret = -ENOMEM;
 389                 goto mpu_put_node;
 390         }
 391
 392         ocmcram_location_data = gen_pool_alloc(sram_pool_data,
 393                                                sizeof(struct emif_regs_amx3));
 394         if (!ocmcram_location_data) {
 395                 dev_err(pm33xx_dev, "PM: Unable to allocate memory from ocmcram\n");
 396                 gen_pool_free(sram_pool, ocmcram_location, *pm_sram->do_wfi_sz);
 397                 ret = -ENOMEM;
 398         }
 399
 400 mpu_put_node:
 401         of_node_put(np);
 402         return ret;
 403 }
 404
 405 static int am33xx_pm_rtc_setup(void)
 406 {
 407         struct device_node *np;
 408         unsigned long val = 0;
 409
 410         np = of_find_node_by_name(NULL, "rtc");
 411
 412         if (of_device_is_available(np)) {
 413                 omap_rtc = rtc_class_open("rtc0");
 414                 if (!omap_rtc) {
 415                         pr_warn("PM: rtc0 not available");
 416                         return -EPROBE_DEFER;
 417                 }
 418
 419                 nvmem_device_read(omap_rtc->nvmem, RTC_SCRATCH_MAGIC_REG * 4,
 420                                   4, (void *)&rtc_magic_val);
 421                 if ((rtc_magic_val & 0xffff) != RTC_REG_BOOT_MAGIC)
 422                         pr_warn("PM: bootloader does not support rtc-only!\n");
 423
 424                 nvmem_device_write(omap_rtc->nvmem, RTC_SCRATCH_MAGIC_REG * 4,
 425                                    4, (void *)&val);
 426                 val = pm_sram->resume_address;
 427                 nvmem_device_write(omap_rtc->nvmem, RTC_SCRATCH_RESUME_REG * 4,
 428                                    4, (void *)&val);
 429         } else {
 430                 pr_warn("PM: no-rtc available, rtc-only mode disabled.\n");
 431         }
 432
 433         return 0;
 434 }
 435
 436 static int am33xx_pm_probe(struct platform_device *pdev)
 437 {
 438         struct device *dev = &pdev->dev;
 439         int ret;
 440
 441         if (!of_machine_is_compatible("ti,am33xx") &&
 442             !of_machine_is_compatible("ti,am43"))
 443                 return -ENODEV;
 444
 445         pm_ops = dev->platform_data;
 446         if (!pm_ops) {
 447                 dev_err(dev, "PM: Cannot get core PM ops!\n");
 448                 return -ENODEV;
 449         }
 450
 451         ret = am43xx_map_gic();
 452         if (ret) {
 453                 pr_err("PM: Could not ioremap GIC base\n");
 454                 return ret;
 455         }
 456
 457         pm_sram = pm_ops->get_sram_addrs();
 458         if (!pm_sram) {
 459                 dev_err(dev, "PM: Cannot get PM asm function addresses!!\n");
 460                 return -ENODEV;
 461         }
 462
 463         m3_ipc = wkup_m3_ipc_get();
 464         if (!m3_ipc) {
 465                 pr_err("PM: Cannot get wkup_m3_ipc handle\n");
 466                 return -EPROBE_DEFER;
 467         }
 468
 469         pm33xx_dev = dev;
 470
 471         ret = am33xx_pm_alloc_sram();
 472         if (ret)
 473                 return ret;
 474
 475         ret = am33xx_pm_rtc_setup();
 476         if (ret)
 477                 goto err_free_sram;
 478
 479         ret = am33xx_push_sram_idle();
 480         if (ret)
 481                 goto err_free_sram;
 482
 483         am33xx_pm_set_ipc_ops();
 484
 485 #ifdef CONFIG_SUSPEND
 486         suspend_set_ops(&am33xx_pm_ops);
 487
 488         /*
 489          * For a system suspend we must flush the caches, we want
 490          * the DDR in self-refresh, we want to save the context
 491          * of the EMIF, and we want the wkup_m3 to handle low-power
 492          * transition.
 493          */
 494         suspend_wfi_flags |= WFI_FLAG_FLUSH_CACHE;
 495         suspend_wfi_flags |= WFI_FLAG_SELF_REFRESH;
 496         suspend_wfi_flags |= WFI_FLAG_SAVE_EMIF;
 497         suspend_wfi_flags |= WFI_FLAG_WAKE_M3;
 498 #endif /* CONFIG_SUSPEND */
 499
 500         ret = pm_ops->init(NULL);
 501         if (ret) {
 502                 dev_err(dev, "Unable to call core pm init!\n");
 503                 ret = -ENODEV;
 504                 goto err_put_wkup_m3_ipc;
 505         }
 506
 507         return 0;
 508
 509 err_put_wkup_m3_ipc:
 510         wkup_m3_ipc_put(m3_ipc);
 511 err_free_sram:
 512         am33xx_pm_free_sram();
 513         pm33xx_dev = NULL;
 514         return ret;
 515 }
 516
 517 static int am33xx_pm_remove(struct platform_device *pdev)
 518 {
 519         suspend_set_ops(NULL);
 520         wkup_m3_ipc_put(m3_ipc);
 521         am33xx_pm_free_sram();
 522         return 0;
 523 }
 524
 525 static struct platform_driver am33xx_pm_driver = {
 526         .driver = {
 527                 .name   = "pm33xx",
 528         },
 529         .probe = am33xx_pm_probe,
 530         .remove = am33xx_pm_remove,
 531 };
 532 module_platform_driver(am33xx_pm_driver);
 533
 534 MODULE_ALIAS("platform:pm33xx");
 535 MODULE_LICENSE("GPL v2");
 536 MODULE_DESCRIPTION("am33xx power management driver");