arch/arm/mach-exynos/suspend.c

   1 /*
   2  * Copyright (c) 2011-2014 Samsung Electronics Co., Ltd.
   3  *              http://www.samsung.com
   4  *
   5  * EXYNOS - Suspend support
   6  *
   7  * Based on arch/arm/mach-s3c2410/pm.c
   8  * Copyright (c) 2006 Simtec Electronics
   9  *      Ben Dooks <ben@simtec.co.uk>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15
  16 #include <linux/init.h>
  17 #include <linux/suspend.h>
  18 #include <linux/syscore_ops.h>
  19 #include <linux/cpu_pm.h>
  20 #include <linux/io.h>
  21 #include <linux/irq.h>
  22 #include <linux/irqchip.h>
  23 #include <linux/irqdomain.h>
  24 #include <linux/of_address.h>
  25 #include <linux/err.h>
  26 #include <linux/regulator/machine.h>
  27 #include <linux/soc/samsung/exynos-pmu.h>
  28 #include <linux/soc/samsung/exynos-regs-pmu.h>
  29
  30 #include <asm/cacheflush.h>
  31 #include <asm/hardware/cache-l2x0.h>
  32 #include <asm/firmware.h>
  33 #include <asm/mcpm.h>
  34 #include <asm/smp_scu.h>
  35 #include <asm/suspend.h>
  36
  37 #include <mach/map.h>
  38
  39 #include <plat/pm-common.h>
  40
  41 #include "common.h"
  42
  43 #define REG_TABLE_END (-1U)
  44
  45 #define EXYNOS5420_CPU_STATE    0x28
  46
  47 /**
  48  * struct exynos_wkup_irq - PMU IRQ to mask mapping
  49  * @hwirq: Hardware IRQ signal of the PMU
  50  * @mask: Mask in PMU wake-up mask register
  51  */
  52 struct exynos_wkup_irq {
  53         unsigned int hwirq;
  54         u32 mask;
  55 };
  56
  57 struct exynos_pm_data {
  58         const struct exynos_wkup_irq *wkup_irq;
  59         unsigned int wake_disable_mask;
  60         unsigned int *release_ret_regs;
  61
  62         void (*pm_prepare)(void);
  63         void (*pm_resume_prepare)(void);
  64         void (*pm_resume)(void);
  65         int (*pm_suspend)(void);
  66         int (*cpu_suspend)(unsigned long);
  67 };
  68
  69 static const struct exynos_pm_data *pm_data;
  70
  71 static int exynos5420_cpu_state;
  72 static unsigned int exynos_pmu_spare3;
  73
  74 /*
  75  * GIC wake-up support
  76  */
  77
  78 static u32 exynos_irqwake_intmask = 0xffffffff;
  79
  80 static const struct exynos_wkup_irq exynos3250_wkup_irq[] = {
  81         { 73, BIT(1) }, /* RTC alarm */
  82         { 74, BIT(2) }, /* RTC tick */
  83         { /* sentinel */ },
  84 };
  85
  86 static const struct exynos_wkup_irq exynos4_wkup_irq[] = {
  87         { 44, BIT(1) }, /* RTC alarm */
  88         { 45, BIT(2) }, /* RTC tick */
  89         { /* sentinel */ },
  90 };
  91
  92 static const struct exynos_wkup_irq exynos5250_wkup_irq[] = {
  93         { 43, BIT(1) }, /* RTC alarm */
  94         { 44, BIT(2) }, /* RTC tick */
  95         { /* sentinel */ },
  96 };
  97
  98 static unsigned int exynos_release_ret_regs[] = {
  99         S5P_PAD_RET_MAUDIO_OPTION,
 100         S5P_PAD_RET_GPIO_OPTION,
 101         S5P_PAD_RET_UART_OPTION,
 102         S5P_PAD_RET_MMCA_OPTION,
 103         S5P_PAD_RET_MMCB_OPTION,
 104         S5P_PAD_RET_EBIA_OPTION,
 105         S5P_PAD_RET_EBIB_OPTION,
 106         REG_TABLE_END,
 107 };
 108
 109 static unsigned int exynos3250_release_ret_regs[] = {
 110         S5P_PAD_RET_MAUDIO_OPTION,
 111         S5P_PAD_RET_GPIO_OPTION,
 112         S5P_PAD_RET_UART_OPTION,
 113         S5P_PAD_RET_MMCA_OPTION,
 114         S5P_PAD_RET_MMCB_OPTION,
 115         S5P_PAD_RET_EBIA_OPTION,
 116         S5P_PAD_RET_EBIB_OPTION,
 117         S5P_PAD_RET_MMC2_OPTION,
 118         S5P_PAD_RET_SPI_OPTION,
 119         REG_TABLE_END,
 120 };
 121
 122 static unsigned int exynos5420_release_ret_regs[] = {
 123         EXYNOS_PAD_RET_DRAM_OPTION,
 124         EXYNOS_PAD_RET_MAUDIO_OPTION,
 125         EXYNOS_PAD_RET_JTAG_OPTION,
 126         EXYNOS5420_PAD_RET_GPIO_OPTION,
 127         EXYNOS5420_PAD_RET_UART_OPTION,
 128         EXYNOS5420_PAD_RET_MMCA_OPTION,
 129         EXYNOS5420_PAD_RET_MMCB_OPTION,
 130         EXYNOS5420_PAD_RET_MMCC_OPTION,
 131         EXYNOS5420_PAD_RET_HSI_OPTION,
 132         EXYNOS_PAD_RET_EBIA_OPTION,
 133         EXYNOS_PAD_RET_EBIB_OPTION,
 134         EXYNOS5420_PAD_RET_SPI_OPTION,
 135         EXYNOS5420_PAD_RET_DRAM_COREBLK_OPTION,
 136         REG_TABLE_END,
 137 };
 138
 139 static int exynos_irq_set_wake(struct irq_data *data, unsigned int state)
 140 {
 141         const struct exynos_wkup_irq *wkup_irq;
 142
 143         if (!pm_data->wkup_irq)
 144                 return -ENOENT;
 145         wkup_irq = pm_data->wkup_irq;
 146
 147         while (wkup_irq->mask) {
 148                 if (wkup_irq->hwirq == data->hwirq) {
 149                         if (!state)
 150                                 exynos_irqwake_intmask |= wkup_irq->mask;
 151                         else
 152                                 exynos_irqwake_intmask &= ~wkup_irq->mask;
 153                         return 0;
 154                 }
 155                 ++wkup_irq;
 156         }
 157
 158         return -ENOENT;
 159 }
 160
 161 static struct irq_chip exynos_pmu_chip = {
 162         .name                   = "PMU",
 163         .irq_eoi                = irq_chip_eoi_parent,
 164         .irq_mask               = irq_chip_mask_parent,
 165         .irq_unmask             = irq_chip_unmask_parent,
 166         .irq_retrigger          = irq_chip_retrigger_hierarchy,
 167         .irq_set_wake           = exynos_irq_set_wake,
 168 #ifdef CONFIG_SMP
 169         .irq_set_affinity       = irq_chip_set_affinity_parent,
 170 #endif
 171 };
 172
 173 static int exynos_pmu_domain_translate(struct irq_domain *d,
 174                                        struct irq_fwspec *fwspec,
 175                                        unsigned long *hwirq,
 176                                        unsigned int *type)
 177 {
 178         if (is_of_node(fwspec->fwnode)) {
 179                 if (fwspec->param_count != 3)
 180                         return -EINVAL;
 181
 182                 /* No PPI should point to this domain */
 183                 if (fwspec->param[0] != 0)
 184                         return -EINVAL;
 185
 186                 *hwirq = fwspec->param[1];
 187                 *type = fwspec->param[2];
 188                 return 0;
 189         }
 190
 191         return -EINVAL;
 192 }
 193
 194 static int exynos_pmu_domain_alloc(struct irq_domain *domain,
 195                                    unsigned int virq,
 196                                    unsigned int nr_irqs, void *data)
 197 {
 198         struct irq_fwspec *fwspec = data;
 199         struct irq_fwspec parent_fwspec;
 200         irq_hw_number_t hwirq;
 201         int i;
 202
 203         if (fwspec->param_count != 3)
 204                 return -EINVAL; /* Not GIC compliant */
 205         if (fwspec->param[0] != 0)
 206                 return -EINVAL; /* No PPI should point to this domain */
 207
 208         hwirq = fwspec->param[1];
 209
 210         for (i = 0; i < nr_irqs; i++)
 211                 irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
 212                                               &exynos_pmu_chip, NULL);
 213
 214         parent_fwspec = *fwspec;
 215         parent_fwspec.fwnode = domain->parent->fwnode;
 216         return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
 217                                             &parent_fwspec);
 218 }
 219
 220 static const struct irq_domain_ops exynos_pmu_domain_ops = {
 221         .translate      = exynos_pmu_domain_translate,
 222         .alloc          = exynos_pmu_domain_alloc,
 223         .free           = irq_domain_free_irqs_common,
 224 };
 225
 226 static int __init exynos_pmu_irq_init(struct device_node *node,
 227                                       struct device_node *parent)
 228 {
 229         struct irq_domain *parent_domain, *domain;
 230
 231         if (!parent) {
 232                 pr_err("%s: no parent, giving up\n", node->full_name);
 233                 return -ENODEV;
 234         }
 235
 236         parent_domain = irq_find_host(parent);
 237         if (!parent_domain) {
 238                 pr_err("%s: unable to obtain parent domain\n", node->full_name);
 239                 return -ENXIO;
 240         }
 241
 242         pmu_base_addr = of_iomap(node, 0);
 243
 244         if (!pmu_base_addr) {
 245                 pr_err("%s: failed to find exynos pmu register\n",
 246                        node->full_name);
 247                 return -ENOMEM;
 248         }
 249
 250         domain = irq_domain_add_hierarchy(parent_domain, 0, 0,
 251                                           node, &exynos_pmu_domain_ops,
 252                                           NULL);
 253         if (!domain) {
 254                 iounmap(pmu_base_addr);
 255                 pmu_base_addr = NULL;
 256                 return -ENOMEM;
 257         }
 258
 259         /*
 260          * Clear the OF_POPULATED flag set in of_irq_init so that
 261          * later the Exynos PMU platform device won't be skipped.
 262          */
 263         of_node_clear_flag(node, OF_POPULATED);
 264
 265         return 0;
 266 }
 267
 268 #define EXYNOS_PMU_IRQ(symbol, name)    IRQCHIP_DECLARE(symbol, name, exynos_pmu_irq_init)
 269
 270 EXYNOS_PMU_IRQ(exynos3250_pmu_irq, "samsung,exynos3250-pmu");
 271 EXYNOS_PMU_IRQ(exynos4210_pmu_irq, "samsung,exynos4210-pmu");
 272 EXYNOS_PMU_IRQ(exynos4212_pmu_irq, "samsung,exynos4212-pmu");
 273 EXYNOS_PMU_IRQ(exynos4412_pmu_irq, "samsung,exynos4412-pmu");
 274 EXYNOS_PMU_IRQ(exynos4415_pmu_irq, "samsung,exynos4415-pmu");
 275 EXYNOS_PMU_IRQ(exynos5250_pmu_irq, "samsung,exynos5250-pmu");
 276 EXYNOS_PMU_IRQ(exynos5420_pmu_irq, "samsung,exynos5420-pmu");
 277
 278 static int exynos_cpu_do_idle(void)
 279 {
 280         /* issue the standby signal into the pm unit. */
 281         cpu_do_idle();
 282
 283         pr_info("Failed to suspend the system\n");
 284         return 1; /* Aborting suspend */
 285 }
 286 static void exynos_flush_cache_all(void)
 287 {
 288         flush_cache_all();
 289         outer_flush_all();
 290 }
 291
 292 static int exynos_cpu_suspend(unsigned long arg)
 293 {
 294         exynos_flush_cache_all();
 295         return exynos_cpu_do_idle();
 296 }
 297
 298 static int exynos3250_cpu_suspend(unsigned long arg)
 299 {
 300         flush_cache_all();
 301         return exynos_cpu_do_idle();
 302 }
 303
 304 static int exynos5420_cpu_suspend(unsigned long arg)
 305 {
 306         /* MCPM works with HW CPU identifiers */
 307         unsigned int mpidr = read_cpuid_mpidr();
 308         unsigned int cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
 309         unsigned int cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
 310
 311         writel_relaxed(0x0, sysram_base_addr + EXYNOS5420_CPU_STATE);
 312
 313         if (IS_ENABLED(CONFIG_EXYNOS5420_MCPM)) {
 314                 mcpm_set_entry_vector(cpu, cluster, exynos_cpu_resume);
 315                 mcpm_cpu_suspend();
 316         }
 317
 318         pr_info("Failed to suspend the system\n");
 319
 320         /* return value != 0 means failure */
 321         return 1;
 322 }
 323
 324 static void exynos_pm_set_wakeup_mask(void)
 325 {
 326         /* Set wake-up mask registers */
 327         pmu_raw_writel(exynos_get_eint_wake_mask(), S5P_EINT_WAKEUP_MASK);
 328         pmu_raw_writel(exynos_irqwake_intmask & ~(1 << 31), S5P_WAKEUP_MASK);
 329 }
 330
 331 static void exynos_pm_enter_sleep_mode(void)
 332 {
 333         /* Set value of power down register for sleep mode */
 334         exynos_sys_powerdown_conf(SYS_SLEEP);
 335         pmu_raw_writel(EXYNOS_SLEEP_MAGIC, S5P_INFORM1);
 336 }
 337
 338 static void exynos_pm_prepare(void)
 339 {
 340         exynos_set_delayed_reset_assertion(false);
 341
 342         /* Set wake-up mask registers */
 343         exynos_pm_set_wakeup_mask();
 344
 345         exynos_pm_enter_sleep_mode();
 346
 347         /* ensure at least INFORM0 has the resume address */
 348         pmu_raw_writel(virt_to_phys(exynos_cpu_resume), S5P_INFORM0);
 349 }
 350
 351 static void exynos3250_pm_prepare(void)
 352 {
 353         unsigned int tmp;
 354
 355         /* Set wake-up mask registers */
 356         exynos_pm_set_wakeup_mask();
 357
 358         tmp = pmu_raw_readl(EXYNOS3_ARM_L2_OPTION);
 359         tmp &= ~EXYNOS5_OPTION_USE_RETENTION;
 360         pmu_raw_writel(tmp, EXYNOS3_ARM_L2_OPTION);
 361
 362         exynos_pm_enter_sleep_mode();
 363
 364         /* ensure at least INFORM0 has the resume address */
 365         pmu_raw_writel(virt_to_phys(exynos_cpu_resume), S5P_INFORM0);
 366 }
 367
 368 static void exynos5420_pm_prepare(void)
 369 {
 370         unsigned int tmp;
 371
 372         /* Set wake-up mask registers */
 373         exynos_pm_set_wakeup_mask();
 374
 375         exynos_pmu_spare3 = pmu_raw_readl(S5P_PMU_SPARE3);
 376         /*
 377          * The cpu state needs to be saved and restored so that the
 378          * secondary CPUs will enter low power start. Though the U-Boot
 379          * is setting the cpu state with low power flag, the kernel
 380          * needs to restore it back in case, the primary cpu fails to
 381          * suspend for any reason.
 382          */
 383         exynos5420_cpu_state = readl_relaxed(sysram_base_addr +
 384                                              EXYNOS5420_CPU_STATE);
 385
 386         exynos_pm_enter_sleep_mode();
 387
 388         /* ensure at least INFORM0 has the resume address */
 389         if (IS_ENABLED(CONFIG_EXYNOS5420_MCPM))
 390                 pmu_raw_writel(virt_to_phys(mcpm_entry_point), S5P_INFORM0);
 391
 392         tmp = pmu_raw_readl(EXYNOS5_ARM_L2_OPTION);
 393         tmp &= ~EXYNOS5_USE_RETENTION;
 394         pmu_raw_writel(tmp, EXYNOS5_ARM_L2_OPTION);
 395
 396         tmp = pmu_raw_readl(EXYNOS5420_SFR_AXI_CGDIS1);
 397         tmp |= EXYNOS5420_UFS;
 398         pmu_raw_writel(tmp, EXYNOS5420_SFR_AXI_CGDIS1);
 399
 400         tmp = pmu_raw_readl(EXYNOS5420_ARM_COMMON_OPTION);
 401         tmp &= ~EXYNOS5420_L2RSTDISABLE_VALUE;
 402         pmu_raw_writel(tmp, EXYNOS5420_ARM_COMMON_OPTION);
 403
 404         tmp = pmu_raw_readl(EXYNOS5420_FSYS2_OPTION);
 405         tmp |= EXYNOS5420_EMULATION;
 406         pmu_raw_writel(tmp, EXYNOS5420_FSYS2_OPTION);
 407
 408         tmp = pmu_raw_readl(EXYNOS5420_PSGEN_OPTION);
 409         tmp |= EXYNOS5420_EMULATION;
 410         pmu_raw_writel(tmp, EXYNOS5420_PSGEN_OPTION);
 411 }
 412
 413
 414 static int exynos_pm_suspend(void)
 415 {
 416         exynos_pm_central_suspend();
 417
 418         /* Setting SEQ_OPTION register */
 419         pmu_raw_writel(S5P_USE_STANDBY_WFI0 | S5P_USE_STANDBY_WFE0,
 420                        S5P_CENTRAL_SEQ_OPTION);
 421
 422         if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
 423                 exynos_cpu_save_register();
 424
 425         return 0;
 426 }
 427
 428 static int exynos5420_pm_suspend(void)
 429 {
 430         u32 this_cluster;
 431
 432         exynos_pm_central_suspend();
 433
 434         /* Setting SEQ_OPTION register */
 435
 436         this_cluster = MPIDR_AFFINITY_LEVEL(read_cpuid_mpidr(), 1);
 437         if (!this_cluster)
 438                 pmu_raw_writel(EXYNOS5420_ARM_USE_STANDBY_WFI0,
 439                                 S5P_CENTRAL_SEQ_OPTION);
 440         else
 441                 pmu_raw_writel(EXYNOS5420_KFC_USE_STANDBY_WFI0,
 442                                 S5P_CENTRAL_SEQ_OPTION);
 443         return 0;
 444 }
 445
 446 static void exynos_pm_release_retention(void)
 447 {
 448         unsigned int i;
 449
 450         for (i = 0; (pm_data->release_ret_regs[i] != REG_TABLE_END); i++)
 451                 pmu_raw_writel(EXYNOS_WAKEUP_FROM_LOWPWR,
 452                                 pm_data->release_ret_regs[i]);
 453 }
 454
 455 static void exynos_pm_resume(void)
 456 {
 457         u32 cpuid = read_cpuid_part();
 458
 459         if (exynos_pm_central_resume())
 460                 goto early_wakeup;
 461
 462         /* For release retention */
 463         exynos_pm_release_retention();
 464
 465         if (cpuid == ARM_CPU_PART_CORTEX_A9)
 466                 scu_enable(S5P_VA_SCU);
 467
 468         if (call_firmware_op(resume) == -ENOSYS
 469             && cpuid == ARM_CPU_PART_CORTEX_A9)
 470                 exynos_cpu_restore_register();
 471
 472 early_wakeup:
 473
 474         /* Clear SLEEP mode set in INFORM1 */
 475         pmu_raw_writel(0x0, S5P_INFORM1);
 476         exynos_set_delayed_reset_assertion(true);
 477 }
 478
 479 static void exynos3250_pm_resume(void)
 480 {
 481         u32 cpuid = read_cpuid_part();
 482
 483         if (exynos_pm_central_resume())
 484                 goto early_wakeup;
 485
 486         /* For release retention */
 487         exynos_pm_release_retention();
 488
 489         pmu_raw_writel(S5P_USE_STANDBY_WFI_ALL, S5P_CENTRAL_SEQ_OPTION);
 490
 491         if (call_firmware_op(resume) == -ENOSYS
 492             && cpuid == ARM_CPU_PART_CORTEX_A9)
 493                 exynos_cpu_restore_register();
 494
 495 early_wakeup:
 496
 497         /* Clear SLEEP mode set in INFORM1 */
 498         pmu_raw_writel(0x0, S5P_INFORM1);
 499 }
 500
 501 static void exynos5420_prepare_pm_resume(void)
 502 {
 503         unsigned int mpidr, cluster;
 504
 505         mpidr = read_cpuid_mpidr();
 506         cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
 507
 508         if (IS_ENABLED(CONFIG_EXYNOS5420_MCPM))
 509                 WARN_ON(mcpm_cpu_powered_up());
 510
 511         if (IS_ENABLED(CONFIG_HW_PERF_EVENTS) && cluster != 0) {
 512                 /*
 513                  * When system is resumed on the LITTLE/KFC core (cluster 1),
 514                  * the DSCR is not properly updated until the power is turned
 515                  * on also for the cluster 0. Enable it for a while to
 516                  * propagate the SPNIDEN and SPIDEN signals from Secure JTAG
 517                  * block and avoid undefined instruction issue on CP14 reset.
 518                  */
 519                 pmu_raw_writel(S5P_CORE_LOCAL_PWR_EN,
 520                                 EXYNOS_COMMON_CONFIGURATION(0));
 521                 pmu_raw_writel(0,
 522                                 EXYNOS_COMMON_CONFIGURATION(0));
 523         }
 524 }
 525
 526 static void exynos5420_pm_resume(void)
 527 {
 528         unsigned long tmp;
 529
 530         /* Restore the CPU0 low power state register */
 531         tmp = pmu_raw_readl(EXYNOS5_ARM_CORE0_SYS_PWR_REG);
 532         pmu_raw_writel(tmp | S5P_CORE_LOCAL_PWR_EN,
 533                        EXYNOS5_ARM_CORE0_SYS_PWR_REG);
 534
 535         /* Restore the sysram cpu state register */
 536         writel_relaxed(exynos5420_cpu_state,
 537                        sysram_base_addr + EXYNOS5420_CPU_STATE);
 538
 539         pmu_raw_writel(EXYNOS5420_USE_STANDBY_WFI_ALL,
 540                         S5P_CENTRAL_SEQ_OPTION);
 541
 542         if (exynos_pm_central_resume())
 543                 goto early_wakeup;
 544
 545         /* For release retention */
 546         exynos_pm_release_retention();
 547
 548         pmu_raw_writel(exynos_pmu_spare3, S5P_PMU_SPARE3);
 549
 550 early_wakeup:
 551
 552         tmp = pmu_raw_readl(EXYNOS5420_SFR_AXI_CGDIS1);
 553         tmp &= ~EXYNOS5420_UFS;
 554         pmu_raw_writel(tmp, EXYNOS5420_SFR_AXI_CGDIS1);
 555
 556         tmp = pmu_raw_readl(EXYNOS5420_FSYS2_OPTION);
 557         tmp &= ~EXYNOS5420_EMULATION;
 558         pmu_raw_writel(tmp, EXYNOS5420_FSYS2_OPTION);
 559
 560         tmp = pmu_raw_readl(EXYNOS5420_PSGEN_OPTION);
 561         tmp &= ~EXYNOS5420_EMULATION;
 562         pmu_raw_writel(tmp, EXYNOS5420_PSGEN_OPTION);
 563
 564         /* Clear SLEEP mode set in INFORM1 */
 565         pmu_raw_writel(0x0, S5P_INFORM1);
 566 }
 567
 568 /*
 569  * Suspend Ops
 570  */
 571
 572 static int exynos_suspend_enter(suspend_state_t state)
 573 {
 574         int ret;
 575
 576         s3c_pm_debug_init();
 577
 578         S3C_PMDBG("%s: suspending the system...\n", __func__);
 579
 580         S3C_PMDBG("%s: wakeup masks: %08x,%08x\n", __func__,
 581                         exynos_irqwake_intmask, exynos_get_eint_wake_mask());
 582
 583         if (exynos_irqwake_intmask == -1U
 584             && exynos_get_eint_wake_mask() == -1U) {
 585                 pr_err("%s: No wake-up sources!\n", __func__);
 586                 pr_err("%s: Aborting sleep\n", __func__);
 587                 return -EINVAL;
 588         }
 589
 590         s3c_pm_save_uarts();
 591         if (pm_data->pm_prepare)
 592                 pm_data->pm_prepare();
 593         flush_cache_all();
 594         s3c_pm_check_store();
 595
 596         ret = call_firmware_op(suspend);
 597         if (ret == -ENOSYS)
 598                 ret = cpu_suspend(0, pm_data->cpu_suspend);
 599         if (ret)
 600                 return ret;
 601
 602         if (pm_data->pm_resume_prepare)
 603                 pm_data->pm_resume_prepare();
 604         s3c_pm_restore_uarts();
 605
 606         S3C_PMDBG("%s: wakeup stat: %08x\n", __func__,
 607                         pmu_raw_readl(S5P_WAKEUP_STAT));
 608
 609         s3c_pm_check_restore();
 610
 611         S3C_PMDBG("%s: resuming the system...\n", __func__);
 612
 613         return 0;
 614 }
 615
 616 static int exynos_suspend_prepare(void)
 617 {
 618         int ret;
 619
 620         /*
 621          * REVISIT: It would be better if struct platform_suspend_ops
 622          * .prepare handler get the suspend_state_t as a parameter to
 623          * avoid hard-coding the suspend to mem state. It's safe to do
 624          * it now only because the suspend_valid_only_mem function is
 625          * used as the .valid callback used to check if a given state
 626          * is supported by the platform anyways.
 627          */
 628         ret = regulator_suspend_prepare(PM_SUSPEND_MEM);
 629         if (ret) {
 630                 pr_err("Failed to prepare regulators for suspend (%d)\n", ret);
 631                 return ret;
 632         }
 633
 634         s3c_pm_check_prepare();
 635
 636         return 0;
 637 }
 638
 639 static void exynos_suspend_finish(void)
 640 {
 641         int ret;
 642
 643         s3c_pm_check_cleanup();
 644
 645         ret = regulator_suspend_finish();
 646         if (ret)
 647                 pr_warn("Failed to resume regulators from suspend (%d)\n", ret);
 648 }
 649
 650 static const struct platform_suspend_ops exynos_suspend_ops = {
 651         .enter          = exynos_suspend_enter,
 652         .prepare        = exynos_suspend_prepare,
 653         .finish         = exynos_suspend_finish,
 654         .valid          = suspend_valid_only_mem,
 655 };
 656
 657 static const struct exynos_pm_data exynos3250_pm_data = {
 658         .wkup_irq       = exynos3250_wkup_irq,
 659         .wake_disable_mask = ((0xFF << 8) | (0x1F << 1)),
 660         .release_ret_regs = exynos3250_release_ret_regs,
 661         .pm_suspend     = exynos_pm_suspend,
 662         .pm_resume      = exynos3250_pm_resume,
 663         .pm_prepare     = exynos3250_pm_prepare,
 664         .cpu_suspend    = exynos3250_cpu_suspend,
 665 };
 666
 667 static const struct exynos_pm_data exynos4_pm_data = {
 668         .wkup_irq       = exynos4_wkup_irq,
 669         .wake_disable_mask = ((0xFF << 8) | (0x1F << 1)),
 670         .release_ret_regs = exynos_release_ret_regs,
 671         .pm_suspend     = exynos_pm_suspend,
 672         .pm_resume      = exynos_pm_resume,
 673         .pm_prepare     = exynos_pm_prepare,
 674         .cpu_suspend    = exynos_cpu_suspend,
 675 };
 676
 677 static const struct exynos_pm_data exynos5250_pm_data = {
 678         .wkup_irq       = exynos5250_wkup_irq,
 679         .wake_disable_mask = ((0xFF << 8) | (0x1F << 1)),
 680         .release_ret_regs = exynos_release_ret_regs,
 681         .pm_suspend     = exynos_pm_suspend,
 682         .pm_resume      = exynos_pm_resume,
 683         .pm_prepare     = exynos_pm_prepare,
 684         .cpu_suspend    = exynos_cpu_suspend,
 685 };
 686
 687 static const struct exynos_pm_data exynos5420_pm_data = {
 688         .wkup_irq       = exynos5250_wkup_irq,
 689         .wake_disable_mask = (0x7F << 7) | (0x1F << 1),
 690         .release_ret_regs = exynos5420_release_ret_regs,
 691         .pm_resume_prepare = exynos5420_prepare_pm_resume,
 692         .pm_resume      = exynos5420_pm_resume,
 693         .pm_suspend     = exynos5420_pm_suspend,
 694         .pm_prepare     = exynos5420_pm_prepare,
 695         .cpu_suspend    = exynos5420_cpu_suspend,
 696 };
 697
 698 static const struct of_device_id exynos_pmu_of_device_ids[] __initconst = {
 699         {
 700                 .compatible = "samsung,exynos3250-pmu",
 701                 .data = &exynos3250_pm_data,
 702         }, {
 703                 .compatible = "samsung,exynos4210-pmu",
 704                 .data = &exynos4_pm_data,
 705         }, {
 706                 .compatible = "samsung,exynos4212-pmu",
 707                 .data = &exynos4_pm_data,
 708         }, {
 709                 .compatible = "samsung,exynos4412-pmu",
 710                 .data = &exynos4_pm_data,
 711         }, {
 712                 .compatible = "samsung,exynos5250-pmu",
 713                 .data = &exynos5250_pm_data,
 714         }, {
 715                 .compatible = "samsung,exynos5420-pmu",
 716                 .data = &exynos5420_pm_data,
 717         },
 718         { /*sentinel*/ },
 719 };
 720
 721 static struct syscore_ops exynos_pm_syscore_ops;
 722
 723 void __init exynos_pm_init(void)
 724 {
 725         const struct of_device_id *match;
 726         struct device_node *np;
 727         u32 tmp;
 728
 729         np = of_find_matching_node_and_match(NULL, exynos_pmu_of_device_ids, &match);
 730         if (!np) {
 731                 pr_err("Failed to find PMU node\n");
 732                 return;
 733         }
 734
 735         if (WARN_ON(!of_find_property(np, "interrupt-controller", NULL))) {
 736                 pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
 737                 of_node_put(np);
 738                 return;
 739         }
 740         of_node_put(np);
 741
 742         pm_data = (const struct exynos_pm_data *) match->data;
 743
 744         /* All wakeup disable */
 745         tmp = pmu_raw_readl(S5P_WAKEUP_MASK);
 746         tmp |= pm_data->wake_disable_mask;
 747         pmu_raw_writel(tmp, S5P_WAKEUP_MASK);
 748
 749         exynos_pm_syscore_ops.suspend   = pm_data->pm_suspend;
 750         exynos_pm_syscore_ops.resume    = pm_data->pm_resume;
 751
 752         register_syscore_ops(&exynos_pm_syscore_ops);
 753         suspend_set_ops(&exynos_suspend_ops);
 754 }