linux/drivers/soc/bcm/bcm2835-power.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Power domain driver for Broadcom BCM2835
   4 *
   5 * Copyright (C) 2018 Broadcom
   6 */
   7
   8#include <dt-bindings/soc/bcm2835-pm.h>
   9#include <linux/clk.h>
  10#include <linux/delay.h>
  11#include <linux/io.h>
  12#include <linux/mfd/bcm2835-pm.h>
  13#include <linux/module.h>
  14#include <linux/platform_device.h>
  15#include <linux/pm_domain.h>
  16#include <linux/reset-controller.h>
  17#include <linux/types.h>
  18
  19#define PM_GNRIC                        0x00
  20#define PM_AUDIO                        0x04
  21#define PM_STATUS                       0x18
  22#define PM_RSTC                         0x1c
  23#define PM_RSTS                         0x20
  24#define PM_WDOG                         0x24
  25#define PM_PADS0                        0x28
  26#define PM_PADS2                        0x2c
  27#define PM_PADS3                        0x30
  28#define PM_PADS4                        0x34
  29#define PM_PADS5                        0x38
  30#define PM_PADS6                        0x3c
  31#define PM_CAM0                         0x44
  32#define PM_CAM0_LDOHPEN                 BIT(2)
  33#define PM_CAM0_LDOLPEN                 BIT(1)
  34#define PM_CAM0_CTRLEN                  BIT(0)
  35
  36#define PM_CAM1                         0x48
  37#define PM_CAM1_LDOHPEN                 BIT(2)
  38#define PM_CAM1_LDOLPEN                 BIT(1)
  39#define PM_CAM1_CTRLEN                  BIT(0)
  40
  41#define PM_CCP2TX                       0x4c
  42#define PM_CCP2TX_LDOEN                 BIT(1)
  43#define PM_CCP2TX_CTRLEN                BIT(0)
  44
  45#define PM_DSI0                         0x50
  46#define PM_DSI0_LDOHPEN                 BIT(2)
  47#define PM_DSI0_LDOLPEN                 BIT(1)
  48#define PM_DSI0_CTRLEN                  BIT(0)
  49
  50#define PM_DSI1                         0x54
  51#define PM_DSI1_LDOHPEN                 BIT(2)
  52#define PM_DSI1_LDOLPEN                 BIT(1)
  53#define PM_DSI1_CTRLEN                  BIT(0)
  54
  55#define PM_HDMI                         0x58
  56#define PM_HDMI_RSTDR                   BIT(19)
  57#define PM_HDMI_LDOPD                   BIT(1)
  58#define PM_HDMI_CTRLEN                  BIT(0)
  59
  60#define PM_USB                          0x5c
  61/* The power gates must be enabled with this bit before enabling the LDO in the
  62 * USB block.
  63 */
  64#define PM_USB_CTRLEN                   BIT(0)
  65
  66#define PM_PXLDO                        0x60
  67#define PM_PXBG                         0x64
  68#define PM_DFT                          0x68
  69#define PM_SMPS                         0x6c
  70#define PM_XOSC                         0x70
  71#define PM_SPAREW                       0x74
  72#define PM_SPARER                       0x78
  73#define PM_AVS_RSTDR                    0x7c
  74#define PM_AVS_STAT                     0x80
  75#define PM_AVS_EVENT                    0x84
  76#define PM_AVS_INTEN                    0x88
  77#define PM_DUMMY                        0xfc
  78
  79#define PM_IMAGE                        0x108
  80#define PM_GRAFX                        0x10c
  81#define PM_PROC                         0x110
  82#define PM_ENAB                         BIT(12)
  83#define PM_ISPRSTN                      BIT(8)
  84#define PM_H264RSTN                     BIT(7)
  85#define PM_PERIRSTN                     BIT(6)
  86#define PM_V3DRSTN                      BIT(6)
  87#define PM_ISFUNC                       BIT(5)
  88#define PM_MRDONE                       BIT(4)
  89#define PM_MEMREP                       BIT(3)
  90#define PM_ISPOW                        BIT(2)
  91#define PM_POWOK                        BIT(1)
  92#define PM_POWUP                        BIT(0)
  93#define PM_INRUSH_SHIFT                 13
  94#define PM_INRUSH_3_5_MA                0
  95#define PM_INRUSH_5_MA                  1
  96#define PM_INRUSH_10_MA                 2
  97#define PM_INRUSH_20_MA                 3
  98#define PM_INRUSH_MASK                  (3 << PM_INRUSH_SHIFT)
  99
 100#define PM_PASSWORD                     0x5a000000
 101
 102#define PM_WDOG_TIME_SET                0x000fffff
 103#define PM_RSTC_WRCFG_CLR               0xffffffcf
 104#define PM_RSTS_HADWRH_SET              0x00000040
 105#define PM_RSTC_WRCFG_SET               0x00000030
 106#define PM_RSTC_WRCFG_FULL_RESET        0x00000020
 107#define PM_RSTC_RESET                   0x00000102
 108
 109#define PM_READ(reg) readl(power->base + (reg))
 110#define PM_WRITE(reg, val) writel(PM_PASSWORD | (val), power->base + (reg))
 111
 112#define ASB_BRDG_VERSION                0x00
 113#define ASB_CPR_CTRL                    0x04
 114
 115#define ASB_V3D_S_CTRL                  0x08
 116#define ASB_V3D_M_CTRL                  0x0c
 117#define ASB_ISP_S_CTRL                  0x10
 118#define ASB_ISP_M_CTRL                  0x14
 119#define ASB_H264_S_CTRL                 0x18
 120#define ASB_H264_M_CTRL                 0x1c
 121
 122#define ASB_REQ_STOP                    BIT(0)
 123#define ASB_ACK                         BIT(1)
 124#define ASB_EMPTY                       BIT(2)
 125#define ASB_FULL                        BIT(3)
 126
 127#define ASB_AXI_BRDG_ID                 0x20
 128
 129#define ASB_READ(reg) readl(power->asb + (reg))
 130#define ASB_WRITE(reg, val) writel(PM_PASSWORD | (val), power->asb + (reg))
 131
 132struct bcm2835_power_domain {
 133        struct generic_pm_domain base;
 134        struct bcm2835_power *power;
 135        u32 domain;
 136        struct clk *clk;
 137};
 138
 139struct bcm2835_power {
 140        struct device           *dev;
 141        /* PM registers. */
 142        void __iomem            *base;
 143        /* AXI Async bridge registers. */
 144        void __iomem            *asb;
 145
 146        struct genpd_onecell_data pd_xlate;
 147        struct bcm2835_power_domain domains[BCM2835_POWER_DOMAIN_COUNT];
 148        struct reset_controller_dev reset;
 149};
 150
 151static int bcm2835_asb_enable(struct bcm2835_power *power, u32 reg)
 152{
 153        u64 start;
 154
 155        if (!reg)
 156                return 0;
 157
 158        start = ktime_get_ns();
 159
 160        /* Enable the module's async AXI bridges. */
 161        ASB_WRITE(reg, ASB_READ(reg) & ~ASB_REQ_STOP);
 162        while (ASB_READ(reg) & ASB_ACK) {
 163                cpu_relax();
 164                if (ktime_get_ns() - start >= 1000)
 165                        return -ETIMEDOUT;
 166        }
 167
 168        return 0;
 169}
 170
 171static int bcm2835_asb_disable(struct bcm2835_power *power, u32 reg)
 172{
 173        u64 start;
 174
 175        if (!reg)
 176                return 0;
 177
 178        start = ktime_get_ns();
 179
 180        /* Enable the module's async AXI bridges. */
 181        ASB_WRITE(reg, ASB_READ(reg) | ASB_REQ_STOP);
 182        while (!(ASB_READ(reg) & ASB_ACK)) {
 183                cpu_relax();
 184                if (ktime_get_ns() - start >= 1000)
 185                        return -ETIMEDOUT;
 186        }
 187
 188        return 0;
 189}
 190
 191static int bcm2835_power_power_off(struct bcm2835_power_domain *pd, u32 pm_reg)
 192{
 193        struct bcm2835_power *power = pd->power;
 194
 195        /* Enable functional isolation */
 196        PM_WRITE(pm_reg, PM_READ(pm_reg) & ~PM_ISFUNC);
 197
 198        /* Enable electrical isolation */
 199        PM_WRITE(pm_reg, PM_READ(pm_reg) & ~PM_ISPOW);
 200
 201        /* Open the power switches. */
 202        PM_WRITE(pm_reg, PM_READ(pm_reg) & ~PM_POWUP);
 203
 204        return 0;
 205}
 206
 207static int bcm2835_power_power_on(struct bcm2835_power_domain *pd, u32 pm_reg)
 208{
 209        struct bcm2835_power *power = pd->power;
 210        struct device *dev = power->dev;
 211        u64 start;
 212        int ret;
 213        int inrush;
 214        bool powok;
 215
 216        /* If it was already powered on by the fw, leave it that way. */
 217        if (PM_READ(pm_reg) & PM_POWUP)
 218                return 0;
 219
 220        /* Enable power.  Allowing too much current at once may result
 221         * in POWOK never getting set, so start low and ramp it up as
 222         * necessary to succeed.
 223         */
 224        powok = false;
 225        for (inrush = PM_INRUSH_3_5_MA; inrush <= PM_INRUSH_20_MA; inrush++) {
 226                PM_WRITE(pm_reg,
 227                         (PM_READ(pm_reg) & ~PM_INRUSH_MASK) |
 228                         (inrush << PM_INRUSH_SHIFT) |
 229                         PM_POWUP);
 230
 231                start = ktime_get_ns();
 232                while (!(powok = !!(PM_READ(pm_reg) & PM_POWOK))) {
 233                        cpu_relax();
 234                        if (ktime_get_ns() - start >= 3000)
 235                                break;
 236                }
 237        }
 238        if (!powok) {
 239                dev_err(dev, "Timeout waiting for %s power OK\n",
 240                        pd->base.name);
 241                ret = -ETIMEDOUT;
 242                goto err_disable_powup;
 243        }
 244
 245        /* Disable electrical isolation */
 246        PM_WRITE(pm_reg, PM_READ(pm_reg) | PM_ISPOW);
 247
 248        /* Repair memory */
 249        PM_WRITE(pm_reg, PM_READ(pm_reg) | PM_MEMREP);
 250        start = ktime_get_ns();
 251        while (!(PM_READ(pm_reg) & PM_MRDONE)) {
 252                cpu_relax();
 253                if (ktime_get_ns() - start >= 1000) {
 254                        dev_err(dev, "Timeout waiting for %s memory repair\n",
 255                                pd->base.name);
 256                        ret = -ETIMEDOUT;
 257                        goto err_disable_ispow;
 258                }
 259        }
 260
 261        /* Disable functional isolation */
 262        PM_WRITE(pm_reg, PM_READ(pm_reg) | PM_ISFUNC);
 263
 264        return 0;
 265
 266err_disable_ispow:
 267        PM_WRITE(pm_reg, PM_READ(pm_reg) & ~PM_ISPOW);
 268err_disable_powup:
 269        PM_WRITE(pm_reg, PM_READ(pm_reg) & ~(PM_POWUP | PM_INRUSH_MASK));
 270        return ret;
 271}
 272
 273static int bcm2835_asb_power_on(struct bcm2835_power_domain *pd,
 274                                u32 pm_reg,
 275                                u32 asb_m_reg,
 276                                u32 asb_s_reg,
 277                                u32 reset_flags)
 278{
 279        struct bcm2835_power *power = pd->power;
 280        int ret;
 281
 282        ret = clk_prepare_enable(pd->clk);
 283        if (ret) {
 284                dev_err(power->dev, "Failed to enable clock for %s\n",
 285                        pd->base.name);
 286                return ret;
 287        }
 288
 289        /* Wait 32 clocks for reset to propagate, 1 us will be enough */
 290        udelay(1);
 291
 292        clk_disable_unprepare(pd->clk);
 293
 294        /* Deassert the resets. */
 295        PM_WRITE(pm_reg, PM_READ(pm_reg) | reset_flags);
 296
 297        ret = clk_prepare_enable(pd->clk);
 298        if (ret) {
 299                dev_err(power->dev, "Failed to enable clock for %s\n",
 300                        pd->base.name);
 301                goto err_enable_resets;
 302        }
 303
 304        ret = bcm2835_asb_enable(power, asb_m_reg);
 305        if (ret) {
 306                dev_err(power->dev, "Failed to enable ASB master for %s\n",
 307                        pd->base.name);
 308                goto err_disable_clk;
 309        }
 310        ret = bcm2835_asb_enable(power, asb_s_reg);
 311        if (ret) {
 312                dev_err(power->dev, "Failed to enable ASB slave for %s\n",
 313                        pd->base.name);
 314                goto err_disable_asb_master;
 315        }
 316
 317        return 0;
 318
 319err_disable_asb_master:
 320        bcm2835_asb_disable(power, asb_m_reg);
 321err_disable_clk:
 322        clk_disable_unprepare(pd->clk);
 323err_enable_resets:
 324        PM_WRITE(pm_reg, PM_READ(pm_reg) & ~reset_flags);
 325        return ret;
 326}
 327
 328static int bcm2835_asb_power_off(struct bcm2835_power_domain *pd,
 329                                 u32 pm_reg,
 330                                 u32 asb_m_reg,
 331                                 u32 asb_s_reg,
 332                                 u32 reset_flags)
 333{
 334        struct bcm2835_power *power = pd->power;
 335        int ret;
 336
 337        ret = bcm2835_asb_disable(power, asb_s_reg);
 338        if (ret) {
 339                dev_warn(power->dev, "Failed to disable ASB slave for %s\n",
 340                         pd->base.name);
 341                return ret;
 342        }
 343        ret = bcm2835_asb_disable(power, asb_m_reg);
 344        if (ret) {
 345                dev_warn(power->dev, "Failed to disable ASB master for %s\n",
 346                         pd->base.name);
 347                bcm2835_asb_enable(power, asb_s_reg);
 348                return ret;
 349        }
 350
 351        clk_disable_unprepare(pd->clk);
 352
 353        /* Assert the resets. */
 354        PM_WRITE(pm_reg, PM_READ(pm_reg) & ~reset_flags);
 355
 356        return 0;
 357}
 358
 359static int bcm2835_power_pd_power_on(struct generic_pm_domain *domain)
 360{
 361        struct bcm2835_power_domain *pd =
 362                container_of(domain, struct bcm2835_power_domain, base);
 363        struct bcm2835_power *power = pd->power;
 364
 365        switch (pd->domain) {
 366        case BCM2835_POWER_DOMAIN_GRAFX:
 367                return bcm2835_power_power_on(pd, PM_GRAFX);
 368
 369        case BCM2835_POWER_DOMAIN_GRAFX_V3D:
 370                return bcm2835_asb_power_on(pd, PM_GRAFX,
 371                                            ASB_V3D_M_CTRL, ASB_V3D_S_CTRL,
 372                                            PM_V3DRSTN);
 373
 374        case BCM2835_POWER_DOMAIN_IMAGE:
 375                return bcm2835_power_power_on(pd, PM_IMAGE);
 376
 377        case BCM2835_POWER_DOMAIN_IMAGE_PERI:
 378                return bcm2835_asb_power_on(pd, PM_IMAGE,
 379                                            0, 0,
 380                                            PM_PERIRSTN);
 381
 382        case BCM2835_POWER_DOMAIN_IMAGE_ISP:
 383                return bcm2835_asb_power_on(pd, PM_IMAGE,
 384                                            ASB_ISP_M_CTRL, ASB_ISP_S_CTRL,
 385                                            PM_ISPRSTN);
 386
 387        case BCM2835_POWER_DOMAIN_IMAGE_H264:
 388                return bcm2835_asb_power_on(pd, PM_IMAGE,
 389                                            ASB_H264_M_CTRL, ASB_H264_S_CTRL,
 390                                            PM_H264RSTN);
 391
 392        case BCM2835_POWER_DOMAIN_USB:
 393                PM_WRITE(PM_USB, PM_USB_CTRLEN);
 394                return 0;
 395
 396        case BCM2835_POWER_DOMAIN_DSI0:
 397                PM_WRITE(PM_DSI0, PM_DSI0_CTRLEN);
 398                PM_WRITE(PM_DSI0, PM_DSI0_CTRLEN | PM_DSI0_LDOHPEN);
 399                return 0;
 400
 401        case BCM2835_POWER_DOMAIN_DSI1:
 402                PM_WRITE(PM_DSI1, PM_DSI1_CTRLEN);
 403                PM_WRITE(PM_DSI1, PM_DSI1_CTRLEN | PM_DSI1_LDOHPEN);
 404                return 0;
 405
 406        case BCM2835_POWER_DOMAIN_CCP2TX:
 407                PM_WRITE(PM_CCP2TX, PM_CCP2TX_CTRLEN);
 408                PM_WRITE(PM_CCP2TX, PM_CCP2TX_CTRLEN | PM_CCP2TX_LDOEN);
 409                return 0;
 410
 411        case BCM2835_POWER_DOMAIN_HDMI:
 412                PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) | PM_HDMI_RSTDR);
 413                PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) | PM_HDMI_CTRLEN);
 414                PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) & ~PM_HDMI_LDOPD);
 415                usleep_range(100, 200);
 416                PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) & ~PM_HDMI_RSTDR);
 417                return 0;
 418
 419        default:
 420                dev_err(power->dev, "Invalid domain %d\n", pd->domain);
 421                return -EINVAL;
 422        }
 423}
 424
 425static int bcm2835_power_pd_power_off(struct generic_pm_domain *domain)
 426{
 427        struct bcm2835_power_domain *pd =
 428                container_of(domain, struct bcm2835_power_domain, base);
 429        struct bcm2835_power *power = pd->power;
 430
 431        switch (pd->domain) {
 432        case BCM2835_POWER_DOMAIN_GRAFX:
 433                return bcm2835_power_power_off(pd, PM_GRAFX);
 434
 435        case BCM2835_POWER_DOMAIN_GRAFX_V3D:
 436                return bcm2835_asb_power_off(pd, PM_GRAFX,
 437                                             ASB_V3D_M_CTRL, ASB_V3D_S_CTRL,
 438                                             PM_V3DRSTN);
 439
 440        case BCM2835_POWER_DOMAIN_IMAGE:
 441                return bcm2835_power_power_off(pd, PM_IMAGE);
 442
 443        case BCM2835_POWER_DOMAIN_IMAGE_PERI:
 444                return bcm2835_asb_power_off(pd, PM_IMAGE,
 445                                             0, 0,
 446                                             PM_PERIRSTN);
 447
 448        case BCM2835_POWER_DOMAIN_IMAGE_ISP:
 449                return bcm2835_asb_power_off(pd, PM_IMAGE,
 450                                             ASB_ISP_M_CTRL, ASB_ISP_S_CTRL,
 451                                             PM_ISPRSTN);
 452
 453        case BCM2835_POWER_DOMAIN_IMAGE_H264:
 454                return bcm2835_asb_power_off(pd, PM_IMAGE,
 455                                             ASB_H264_M_CTRL, ASB_H264_S_CTRL,
 456                                             PM_H264RSTN);
 457
 458        case BCM2835_POWER_DOMAIN_USB:
 459                PM_WRITE(PM_USB, 0);
 460                return 0;
 461
 462        case BCM2835_POWER_DOMAIN_DSI0:
 463                PM_WRITE(PM_DSI0, PM_DSI0_CTRLEN);
 464                PM_WRITE(PM_DSI0, 0);
 465                return 0;
 466
 467        case BCM2835_POWER_DOMAIN_DSI1:
 468                PM_WRITE(PM_DSI1, PM_DSI1_CTRLEN);
 469                PM_WRITE(PM_DSI1, 0);
 470                return 0;
 471
 472        case BCM2835_POWER_DOMAIN_CCP2TX:
 473                PM_WRITE(PM_CCP2TX, PM_CCP2TX_CTRLEN);
 474                PM_WRITE(PM_CCP2TX, 0);
 475                return 0;
 476
 477        case BCM2835_POWER_DOMAIN_HDMI:
 478                PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) | PM_HDMI_LDOPD);
 479                PM_WRITE(PM_HDMI, PM_READ(PM_HDMI) & ~PM_HDMI_CTRLEN);
 480                return 0;
 481
 482        default:
 483                dev_err(power->dev, "Invalid domain %d\n", pd->domain);
 484                return -EINVAL;
 485        }
 486}
 487
 488static int
 489bcm2835_init_power_domain(struct bcm2835_power *power,
 490                          int pd_xlate_index, const char *name)
 491{
 492        struct device *dev = power->dev;
 493        struct bcm2835_power_domain *dom = &power->domains[pd_xlate_index];
 494
 495        dom->clk = devm_clk_get(dev->parent, name);
 496        if (IS_ERR(dom->clk)) {
 497                int ret = PTR_ERR(dom->clk);
 498
 499                if (ret == -EPROBE_DEFER)
 500                        return ret;
 501
 502                /* Some domains don't have a clk, so make sure that we
 503                 * don't deref an error pointer later.
 504                 */
 505                dom->clk = NULL;
 506        }
 507
 508        dom->base.name = name;
 509        dom->base.power_on = bcm2835_power_pd_power_on;
 510        dom->base.power_off = bcm2835_power_pd_power_off;
 511
 512        dom->domain = pd_xlate_index;
 513        dom->power = power;
 514
 515        /* XXX: on/off at boot? */
 516        pm_genpd_init(&dom->base, NULL, true);
 517
 518        power->pd_xlate.domains[pd_xlate_index] = &dom->base;
 519
 520        return 0;
 521}
 522
 523/** bcm2835_reset_reset - Resets a block that has a reset line in the
 524 * PM block.
 525 *
 526 * The consumer of the reset controller must have the power domain up
 527 * -- there's no reset ability with the power domain down.  To reset
 528 * the sub-block, we just disable its access to memory through the
 529 * ASB, reset, and re-enable.
 530 */
 531static int bcm2835_reset_reset(struct reset_controller_dev *rcdev,
 532                               unsigned long id)
 533{
 534        struct bcm2835_power *power = container_of(rcdev, struct bcm2835_power,
 535                                                   reset);
 536        struct bcm2835_power_domain *pd;
 537        int ret;
 538
 539        switch (id) {
 540        case BCM2835_RESET_V3D:
 541                pd = &power->domains[BCM2835_POWER_DOMAIN_GRAFX_V3D];
 542                break;
 543        case BCM2835_RESET_H264:
 544                pd = &power->domains[BCM2835_POWER_DOMAIN_IMAGE_H264];
 545                break;
 546        case BCM2835_RESET_ISP:
 547                pd = &power->domains[BCM2835_POWER_DOMAIN_IMAGE_ISP];
 548                break;
 549        default:
 550                dev_err(power->dev, "Bad reset id %ld\n", id);
 551                return -EINVAL;
 552        }
 553
 554        ret = bcm2835_power_pd_power_off(&pd->base);
 555        if (ret)
 556                return ret;
 557
 558        return bcm2835_power_pd_power_on(&pd->base);
 559}
 560
 561static int bcm2835_reset_status(struct reset_controller_dev *rcdev,
 562                                unsigned long id)
 563{
 564        struct bcm2835_power *power = container_of(rcdev, struct bcm2835_power,
 565                                                   reset);
 566
 567        switch (id) {
 568        case BCM2835_RESET_V3D:
 569                return !PM_READ(PM_GRAFX & PM_V3DRSTN);
 570        case BCM2835_RESET_H264:
 571                return !PM_READ(PM_IMAGE & PM_H264RSTN);
 572        case BCM2835_RESET_ISP:
 573                return !PM_READ(PM_IMAGE & PM_ISPRSTN);
 574        default:
 575                return -EINVAL;
 576        }
 577}
 578
 579static const struct reset_control_ops bcm2835_reset_ops = {
 580        .reset = bcm2835_reset_reset,
 581        .status = bcm2835_reset_status,
 582};
 583
 584static const char *const power_domain_names[] = {
 585        [BCM2835_POWER_DOMAIN_GRAFX] = "grafx",
 586        [BCM2835_POWER_DOMAIN_GRAFX_V3D] = "v3d",
 587
 588        [BCM2835_POWER_DOMAIN_IMAGE] = "image",
 589        [BCM2835_POWER_DOMAIN_IMAGE_PERI] = "peri_image",
 590        [BCM2835_POWER_DOMAIN_IMAGE_H264] = "h264",
 591        [BCM2835_POWER_DOMAIN_IMAGE_ISP] = "isp",
 592
 593        [BCM2835_POWER_DOMAIN_USB] = "usb",
 594        [BCM2835_POWER_DOMAIN_DSI0] = "dsi0",
 595        [BCM2835_POWER_DOMAIN_DSI1] = "dsi1",
 596        [BCM2835_POWER_DOMAIN_CAM0] = "cam0",
 597        [BCM2835_POWER_DOMAIN_CAM1] = "cam1",
 598        [BCM2835_POWER_DOMAIN_CCP2TX] = "ccp2tx",
 599        [BCM2835_POWER_DOMAIN_HDMI] = "hdmi",
 600};
 601
 602static int bcm2835_power_probe(struct platform_device *pdev)
 603{
 604        struct bcm2835_pm *pm = dev_get_drvdata(pdev->dev.parent);
 605        struct device *dev = &pdev->dev;
 606        struct bcm2835_power *power;
 607        static const struct {
 608                int parent, child;
 609        } domain_deps[] = {
 610                { BCM2835_POWER_DOMAIN_GRAFX, BCM2835_POWER_DOMAIN_GRAFX_V3D },
 611                { BCM2835_POWER_DOMAIN_IMAGE, BCM2835_POWER_DOMAIN_IMAGE_PERI },
 612                { BCM2835_POWER_DOMAIN_IMAGE, BCM2835_POWER_DOMAIN_IMAGE_H264 },
 613                { BCM2835_POWER_DOMAIN_IMAGE, BCM2835_POWER_DOMAIN_IMAGE_ISP },
 614                { BCM2835_POWER_DOMAIN_IMAGE_PERI, BCM2835_POWER_DOMAIN_USB },
 615                { BCM2835_POWER_DOMAIN_IMAGE_PERI, BCM2835_POWER_DOMAIN_CAM0 },
 616                { BCM2835_POWER_DOMAIN_IMAGE_PERI, BCM2835_POWER_DOMAIN_CAM1 },
 617        };
 618        int ret = 0, i;
 619        u32 id;
 620
 621        power = devm_kzalloc(dev, sizeof(*power), GFP_KERNEL);
 622        if (!power)
 623                return -ENOMEM;
 624        platform_set_drvdata(pdev, power);
 625
 626        power->dev = dev;
 627        power->base = pm->base;
 628        power->asb = pm->asb;
 629
 630        id = ASB_READ(ASB_AXI_BRDG_ID);
 631        if (id != 0x62726467 /* "BRDG" */) {
 632                dev_err(dev, "ASB register ID returned 0x%08x\n", id);
 633                return -ENODEV;
 634        }
 635
 636        power->pd_xlate.domains = devm_kcalloc(dev,
 637                                               ARRAY_SIZE(power_domain_names),
 638                                               sizeof(*power->pd_xlate.domains),
 639                                               GFP_KERNEL);
 640        if (!power->pd_xlate.domains)
 641                return -ENOMEM;
 642
 643        power->pd_xlate.num_domains = ARRAY_SIZE(power_domain_names);
 644
 645        for (i = 0; i < ARRAY_SIZE(power_domain_names); i++) {
 646                ret = bcm2835_init_power_domain(power, i, power_domain_names[i]);
 647                if (ret)
 648                        goto fail;
 649        }
 650
 651        for (i = 0; i < ARRAY_SIZE(domain_deps); i++) {
 652                pm_genpd_add_subdomain(&power->domains[domain_deps[i].parent].base,
 653                                       &power->domains[domain_deps[i].child].base);
 654        }
 655
 656        power->reset.owner = THIS_MODULE;
 657        power->reset.nr_resets = BCM2835_RESET_COUNT;
 658        power->reset.ops = &bcm2835_reset_ops;
 659        power->reset.of_node = dev->parent->of_node;
 660
 661        ret = devm_reset_controller_register(dev, &power->reset);
 662        if (ret)
 663                goto fail;
 664
 665        of_genpd_add_provider_onecell(dev->parent->of_node, &power->pd_xlate);
 666
 667        dev_info(dev, "Broadcom BCM2835 power domains driver");
 668        return 0;
 669
 670fail:
 671        for (i = 0; i < ARRAY_SIZE(power_domain_names); i++) {
 672                struct generic_pm_domain *dom = &power->domains[i].base;
 673
 674                if (dom->name)
 675                        pm_genpd_remove(dom);
 676        }
 677        return ret;
 678}
 679
 680static int bcm2835_power_remove(struct platform_device *pdev)
 681{
 682        return 0;
 683}
 684
 685static struct platform_driver bcm2835_power_driver = {
 686        .probe          = bcm2835_power_probe,
 687        .remove         = bcm2835_power_remove,
 688        .driver = {
 689                .name = "bcm2835-power",
 690        },
 691};
 692module_platform_driver(bcm2835_power_driver);
 693
 694MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
 695MODULE_DESCRIPTION("Driver for Broadcom BCM2835 PM power domains and reset");
 696MODULE_LICENSE("GPL");
 697