linux/drivers/gpu/drm/amd/amdgpu/smu_v11_0_i2c.c
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   1/*
   2 * Copyright 2019 Advanced Micro Devices, Inc.
   3 *
   4 * Permission is hereby granted, free of charge, to any person obtaining a
   5 * copy of this software and associated documentation files (the "Software"),
   6 * to deal in the Software without restriction, including without limitation
   7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8 * and/or sell copies of the Software, and to permit persons to whom the
   9 * Software is furnished to do so, subject to the following conditions:
  10 *
  11 * The above copyright notice and this permission notice shall be included in
  12 * all copies or substantial portions of the Software.
  13 *
  14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  20 * OTHER DEALINGS IN THE SOFTWARE.
  21 *
  22 */
  23
  24#include "smuio/smuio_11_0_0_offset.h"
  25#include "smuio/smuio_11_0_0_sh_mask.h"
  26
  27#include "smu_v11_0_i2c.h"
  28#include "amdgpu.h"
  29#include "soc15_common.h"
  30#include <drm/drm_fixed.h>
  31#include <drm/drm_drv.h>
  32#include "amdgpu_amdkfd.h"
  33#include <linux/i2c.h>
  34#include <linux/pci.h>
  35#include "amdgpu_ras.h"
  36
  37/* error codes */
  38#define I2C_OK                0
  39#define I2C_NAK_7B_ADDR_NOACK 1
  40#define I2C_NAK_TXDATA_NOACK  2
  41#define I2C_TIMEOUT           4
  42#define I2C_SW_TIMEOUT        8
  43#define I2C_ABORT             0x10
  44
  45/* I2C transaction flags */
  46#define I2C_NO_STOP     1
  47#define I2C_RESTART     2
  48
  49#define to_amdgpu_device(x) (container_of(x, struct amdgpu_ras, eeprom_control.eeprom_accessor))->adev
  50#define to_eeprom_control(x) container_of(x, struct amdgpu_ras_eeprom_control, eeprom_accessor)
  51
  52static void smu_v11_0_i2c_set_clock_gating(struct i2c_adapter *control, bool en)
  53{
  54        struct amdgpu_device *adev = to_amdgpu_device(control);
  55        uint32_t reg = RREG32_SOC15(SMUIO, 0, mmSMUIO_PWRMGT);
  56
  57        reg = REG_SET_FIELD(reg, SMUIO_PWRMGT, i2c_clk_gate_en, en ? 1 : 0);
  58        WREG32_SOC15(SMUIO, 0, mmSMUIO_PWRMGT, reg);
  59}
  60
  61
  62static void smu_v11_0_i2c_enable(struct i2c_adapter *control, bool enable)
  63{
  64        struct amdgpu_device *adev = to_amdgpu_device(control);
  65
  66        WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE, enable ? 1 : 0);
  67}
  68
  69static void smu_v11_0_i2c_clear_status(struct i2c_adapter *control)
  70{
  71        struct amdgpu_device *adev = to_amdgpu_device(control);
  72        /* do */
  73        {
  74                RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_CLR_INTR);
  75
  76        } /* while (reg_CKSVII2C_ic_clr_intr == 0) */
  77}
  78
  79static void smu_v11_0_i2c_configure(struct i2c_adapter *control)
  80{
  81        struct amdgpu_device *adev = to_amdgpu_device(control);
  82        uint32_t reg = 0;
  83
  84        reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_SLAVE_DISABLE, 1);
  85        reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_RESTART_EN, 1);
  86        reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_10BITADDR_MASTER, 0);
  87        reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_10BITADDR_SLAVE, 0);
  88        /* Standard mode */
  89        reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_MAX_SPEED_MODE, 2);
  90        reg = REG_SET_FIELD(reg, CKSVII2C_IC_CON, IC_MASTER_MODE, 1);
  91
  92        WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_CON, reg);
  93}
  94
  95static void smu_v11_0_i2c_set_clock(struct i2c_adapter *control)
  96{
  97        struct amdgpu_device *adev = to_amdgpu_device(control);
  98
  99        /*
 100         * Standard mode speed, These values are taken from SMUIO MAS,
 101         * but are different from what is given is
 102         * Synopsys spec. The values here are based on assumption
 103         * that refclock is 100MHz
 104         *
 105         * Configuration for standard mode; Speed = 100kbps
 106         * Scale linearly, for now only support standard speed clock
 107         * This will work only with 100M ref clock
 108         *
 109         * TBD:Change the calculation to take into account ref clock values also.
 110         */
 111
 112        WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_FS_SPKLEN, 2);
 113        WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_SS_SCL_HCNT, 120);
 114        WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_SS_SCL_LCNT, 130);
 115        WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_SDA_HOLD, 20);
 116}
 117
 118static void smu_v11_0_i2c_set_address(struct i2c_adapter *control, uint8_t address)
 119{
 120        struct amdgpu_device *adev = to_amdgpu_device(control);
 121
 122        /* Convert fromr 8-bit to 7-bit address */
 123        address >>= 1;
 124        WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_TAR, (address & 0xFF));
 125}
 126
 127static uint32_t smu_v11_0_i2c_poll_tx_status(struct i2c_adapter *control)
 128{
 129        struct amdgpu_device *adev = to_amdgpu_device(control);
 130        uint32_t ret = I2C_OK;
 131        uint32_t reg, reg_c_tx_abrt_source;
 132
 133        /*Check if transmission is completed */
 134        unsigned long  timeout_counter = jiffies + msecs_to_jiffies(20);
 135
 136        do {
 137                if (time_after(jiffies, timeout_counter)) {
 138                        ret |= I2C_SW_TIMEOUT;
 139                        break;
 140                }
 141
 142                reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_STATUS);
 143
 144        } while (REG_GET_FIELD(reg, CKSVII2C_IC_STATUS, TFE) == 0);
 145
 146        if (ret != I2C_OK)
 147                return ret;
 148
 149        /* This only checks if NAK is received and transaction got aborted */
 150        reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_INTR_STAT);
 151
 152        if (REG_GET_FIELD(reg, CKSVII2C_IC_INTR_STAT, R_TX_ABRT) == 1) {
 153                reg_c_tx_abrt_source = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_TX_ABRT_SOURCE);
 154                DRM_INFO("TX was terminated, IC_TX_ABRT_SOURCE val is:%x", reg_c_tx_abrt_source);
 155
 156                /* Check for stop due to NACK */
 157                if (REG_GET_FIELD(reg_c_tx_abrt_source,
 158                                  CKSVII2C_IC_TX_ABRT_SOURCE,
 159                                  ABRT_TXDATA_NOACK) == 1) {
 160
 161                        ret |= I2C_NAK_TXDATA_NOACK;
 162
 163                } else if (REG_GET_FIELD(reg_c_tx_abrt_source,
 164                                         CKSVII2C_IC_TX_ABRT_SOURCE,
 165                                         ABRT_7B_ADDR_NOACK) == 1) {
 166
 167                        ret |= I2C_NAK_7B_ADDR_NOACK;
 168                } else {
 169                        ret |= I2C_ABORT;
 170                }
 171
 172                smu_v11_0_i2c_clear_status(control);
 173        }
 174
 175        return ret;
 176}
 177
 178static uint32_t smu_v11_0_i2c_poll_rx_status(struct i2c_adapter *control)
 179{
 180        struct amdgpu_device *adev = to_amdgpu_device(control);
 181        uint32_t ret = I2C_OK;
 182        uint32_t reg_ic_status, reg_c_tx_abrt_source;
 183
 184        reg_c_tx_abrt_source = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_TX_ABRT_SOURCE);
 185
 186        /* If slave is not present */
 187        if (REG_GET_FIELD(reg_c_tx_abrt_source,
 188                          CKSVII2C_IC_TX_ABRT_SOURCE,
 189                          ABRT_7B_ADDR_NOACK) == 1) {
 190                ret |= I2C_NAK_7B_ADDR_NOACK;
 191
 192                smu_v11_0_i2c_clear_status(control);
 193        } else {  /* wait till some data is there in RXFIFO */
 194                /* Poll for some byte in RXFIFO */
 195                unsigned long  timeout_counter = jiffies + msecs_to_jiffies(20);
 196
 197                do {
 198                        if (time_after(jiffies, timeout_counter)) {
 199                                ret |= I2C_SW_TIMEOUT;
 200                                break;
 201                        }
 202
 203                        reg_ic_status = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_STATUS);
 204
 205                } while (REG_GET_FIELD(reg_ic_status, CKSVII2C_IC_STATUS, RFNE) == 0);
 206        }
 207
 208        return ret;
 209}
 210
 211
 212
 213
 214/**
 215 * smu_v11_0_i2c_transmit - Send a block of data over the I2C bus to a slave device.
 216 *
 217 * @address: The I2C address of the slave device.
 218 * @data: The data to transmit over the bus.
 219 * @numbytes: The amount of data to transmit.
 220 * @i2c_flag: Flags for transmission
 221 *
 222 * Returns 0 on success or error.
 223 */
 224static uint32_t smu_v11_0_i2c_transmit(struct i2c_adapter *control,
 225                                  uint8_t address, uint8_t *data,
 226                                  uint32_t numbytes, uint32_t i2c_flag)
 227{
 228        struct amdgpu_device *adev = to_amdgpu_device(control);
 229        uint32_t bytes_sent, reg, ret = 0;
 230        unsigned long  timeout_counter;
 231
 232        bytes_sent = 0;
 233
 234        DRM_DEBUG_DRIVER("I2C_Transmit(), address = %x, bytes = %d , data: ",
 235                 (uint16_t)address, numbytes);
 236
 237        if (drm_debug & DRM_UT_DRIVER) {
 238                print_hex_dump(KERN_INFO, "data: ", DUMP_PREFIX_NONE,
 239                               16, 1, data, numbytes, false);
 240        }
 241
 242        /* Set the I2C slave address */
 243        smu_v11_0_i2c_set_address(control, address);
 244        /* Enable I2C */
 245        smu_v11_0_i2c_enable(control, true);
 246
 247        /* Clear status bits */
 248        smu_v11_0_i2c_clear_status(control);
 249
 250
 251        timeout_counter = jiffies + msecs_to_jiffies(20);
 252
 253        while (numbytes > 0) {
 254                reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_STATUS);
 255                if (REG_GET_FIELD(reg, CKSVII2C_IC_STATUS, TFNF)) {
 256                        do {
 257                                reg = 0;
 258                                /*
 259                                 * Prepare transaction, no need to set RESTART. I2C engine will send
 260                                 * START as soon as it sees data in TXFIFO
 261                                 */
 262                                if (bytes_sent == 0)
 263                                        reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, RESTART,
 264                                                            (i2c_flag & I2C_RESTART) ? 1 : 0);
 265                                reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, DAT, data[bytes_sent]);
 266
 267                                /* determine if we need to send STOP bit or not */
 268                                if (numbytes == 1)
 269                                        /* Final transaction, so send stop unless I2C_NO_STOP */
 270                                        reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, STOP,
 271                                                            (i2c_flag & I2C_NO_STOP) ? 0 : 1);
 272                                /* Write */
 273                                reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, CMD, 0);
 274                                WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_DATA_CMD, reg);
 275
 276                                /* Record that the bytes were transmitted */
 277                                bytes_sent++;
 278                                numbytes--;
 279
 280                                reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_STATUS);
 281
 282                        } while (numbytes &&  REG_GET_FIELD(reg, CKSVII2C_IC_STATUS, TFNF));
 283                }
 284
 285                /*
 286                 * We waited too long for the transmission FIFO to become not-full.
 287                 * Exit the loop with error.
 288                 */
 289                if (time_after(jiffies, timeout_counter)) {
 290                        ret |= I2C_SW_TIMEOUT;
 291                        goto Err;
 292                }
 293        }
 294
 295        ret = smu_v11_0_i2c_poll_tx_status(control);
 296
 297Err:
 298        /* Any error, no point in proceeding */
 299        if (ret != I2C_OK) {
 300                if (ret & I2C_SW_TIMEOUT)
 301                        DRM_ERROR("TIMEOUT ERROR !!!");
 302
 303                if (ret & I2C_NAK_7B_ADDR_NOACK)
 304                        DRM_ERROR("Received I2C_NAK_7B_ADDR_NOACK !!!");
 305
 306
 307                if (ret & I2C_NAK_TXDATA_NOACK)
 308                        DRM_ERROR("Received I2C_NAK_TXDATA_NOACK !!!");
 309        }
 310
 311        return ret;
 312}
 313
 314
 315/**
 316 * smu_v11_0_i2c_receive - Receive a block of data over the I2C bus from a slave device.
 317 *
 318 * @address: The I2C address of the slave device.
 319 * @numbytes: The amount of data to transmit.
 320 * @i2c_flag: Flags for transmission
 321 *
 322 * Returns 0 on success or error.
 323 */
 324static uint32_t smu_v11_0_i2c_receive(struct i2c_adapter *control,
 325                                 uint8_t address, uint8_t *data,
 326                                 uint32_t numbytes, uint8_t i2c_flag)
 327{
 328        struct amdgpu_device *adev = to_amdgpu_device(control);
 329        uint32_t bytes_received, ret = I2C_OK;
 330
 331        bytes_received = 0;
 332
 333        /* Set the I2C slave address */
 334        smu_v11_0_i2c_set_address(control, address);
 335
 336        /* Enable I2C */
 337        smu_v11_0_i2c_enable(control, true);
 338
 339        while (numbytes > 0) {
 340                uint32_t reg = 0;
 341
 342                smu_v11_0_i2c_clear_status(control);
 343
 344
 345                /* Prepare transaction */
 346
 347                /* Each time we disable I2C, so this is not a restart */
 348                if (bytes_received == 0)
 349                        reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, RESTART,
 350                                            (i2c_flag & I2C_RESTART) ? 1 : 0);
 351
 352                reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, DAT, 0);
 353                /* Read */
 354                reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, CMD, 1);
 355
 356                /* Transmitting last byte */
 357                if (numbytes == 1)
 358                        /* Final transaction, so send stop if requested */
 359                        reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, STOP,
 360                                            (i2c_flag & I2C_NO_STOP) ? 0 : 1);
 361
 362                WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_DATA_CMD, reg);
 363
 364                ret = smu_v11_0_i2c_poll_rx_status(control);
 365
 366                /* Any error, no point in proceeding */
 367                if (ret != I2C_OK) {
 368                        if (ret & I2C_SW_TIMEOUT)
 369                                DRM_ERROR("TIMEOUT ERROR !!!");
 370
 371                        if (ret & I2C_NAK_7B_ADDR_NOACK)
 372                                DRM_ERROR("Received I2C_NAK_7B_ADDR_NOACK !!!");
 373
 374                        if (ret & I2C_NAK_TXDATA_NOACK)
 375                                DRM_ERROR("Received I2C_NAK_TXDATA_NOACK !!!");
 376
 377                        break;
 378                }
 379
 380                reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_DATA_CMD);
 381                data[bytes_received] = REG_GET_FIELD(reg, CKSVII2C_IC_DATA_CMD, DAT);
 382
 383                /* Record that the bytes were received */
 384                bytes_received++;
 385                numbytes--;
 386        }
 387
 388        DRM_DEBUG_DRIVER("I2C_Receive(), address = %x, bytes = %d, data :",
 389                  (uint16_t)address, bytes_received);
 390
 391        if (drm_debug & DRM_UT_DRIVER) {
 392                print_hex_dump(KERN_INFO, "data: ", DUMP_PREFIX_NONE,
 393                               16, 1, data, bytes_received, false);
 394        }
 395
 396        return ret;
 397}
 398
 399static void smu_v11_0_i2c_abort(struct i2c_adapter *control)
 400{
 401        struct amdgpu_device *adev = to_amdgpu_device(control);
 402        uint32_t reg = 0;
 403
 404        /* Enable I2C engine; */
 405        reg = REG_SET_FIELD(reg, CKSVII2C_IC_ENABLE, ENABLE, 1);
 406        WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE, reg);
 407
 408        /* Abort previous transaction */
 409        reg = REG_SET_FIELD(reg, CKSVII2C_IC_ENABLE, ABORT, 1);
 410        WREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE, reg);
 411
 412        DRM_DEBUG_DRIVER("I2C_Abort() Done.");
 413}
 414
 415
 416static bool smu_v11_0_i2c_activity_done(struct i2c_adapter *control)
 417{
 418        struct amdgpu_device *adev = to_amdgpu_device(control);
 419
 420        const uint32_t IDLE_TIMEOUT = 1024;
 421        uint32_t timeout_count = 0;
 422        uint32_t reg_ic_enable, reg_ic_enable_status, reg_ic_clr_activity;
 423
 424        reg_ic_enable_status = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE_STATUS);
 425        reg_ic_enable = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE);
 426
 427
 428        if ((REG_GET_FIELD(reg_ic_enable, CKSVII2C_IC_ENABLE, ENABLE) == 0) &&
 429            (REG_GET_FIELD(reg_ic_enable_status, CKSVII2C_IC_ENABLE_STATUS, IC_EN) == 1)) {
 430                /*
 431                 * Nobody is using I2C engine, but engine remains active because
 432                 * someone missed to send STOP
 433                 */
 434                smu_v11_0_i2c_abort(control);
 435        } else if (REG_GET_FIELD(reg_ic_enable, CKSVII2C_IC_ENABLE, ENABLE) == 0) {
 436                /* Nobody is using I2C engine */
 437                return true;
 438        }
 439
 440        /* Keep reading activity bit until it's cleared */
 441        do {
 442                reg_ic_clr_activity = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_CLR_ACTIVITY);
 443
 444                if (REG_GET_FIELD(reg_ic_clr_activity,
 445                    CKSVII2C_IC_CLR_ACTIVITY, CLR_ACTIVITY) == 0)
 446                        return true;
 447
 448                ++timeout_count;
 449
 450        } while (timeout_count < IDLE_TIMEOUT);
 451
 452        return false;
 453}
 454
 455static void smu_v11_0_i2c_init(struct i2c_adapter *control)
 456{
 457        /* Disable clock gating */
 458        smu_v11_0_i2c_set_clock_gating(control, false);
 459
 460        if (!smu_v11_0_i2c_activity_done(control))
 461                DRM_WARN("I2C busy !");
 462
 463        /* Disable I2C */
 464        smu_v11_0_i2c_enable(control, false);
 465
 466        /* Configure I2C to operate as master and in standard mode */
 467        smu_v11_0_i2c_configure(control);
 468
 469        /* Initialize the clock to 50 kHz default */
 470        smu_v11_0_i2c_set_clock(control);
 471
 472}
 473
 474static void smu_v11_0_i2c_fini(struct i2c_adapter *control)
 475{
 476        struct amdgpu_device *adev = to_amdgpu_device(control);
 477        uint32_t reg_ic_enable_status, reg_ic_enable;
 478
 479        smu_v11_0_i2c_enable(control, false);
 480
 481        /* Double check if disabled, else force abort */
 482        reg_ic_enable_status = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE_STATUS);
 483        reg_ic_enable = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_ENABLE);
 484
 485        if ((REG_GET_FIELD(reg_ic_enable, CKSVII2C_IC_ENABLE, ENABLE) == 0) &&
 486            (REG_GET_FIELD(reg_ic_enable_status,
 487                           CKSVII2C_IC_ENABLE_STATUS, IC_EN) == 1)) {
 488                /*
 489                 * Nobody is using I2C engine, but engine remains active because
 490                 * someone missed to send STOP
 491                 */
 492                smu_v11_0_i2c_abort(control);
 493        }
 494
 495        /* Restore clock gating */
 496
 497        /*
 498         * TODO Reenabling clock gating seems to break subsequent SMU operation
 499         *      on the I2C bus. My guess is that SMU doesn't disable clock gating like
 500         *      we do here before working with the bus. So for now just don't restore
 501         *      it but later work with SMU to see if they have this issue and can
 502         *      update their code appropriately
 503         */
 504        /* smu_v11_0_i2c_set_clock_gating(control, true); */
 505
 506}
 507
 508static bool smu_v11_0_i2c_bus_lock(struct i2c_adapter *control)
 509{
 510        struct amdgpu_device *adev = to_amdgpu_device(control);
 511
 512        /* Send  PPSMC_MSG_RequestI2CBus */
 513        if (!adev->powerplay.pp_funcs->smu_i2c_bus_access)
 514                goto Fail;
 515
 516
 517        if (!adev->powerplay.pp_funcs->smu_i2c_bus_access(adev->powerplay.pp_handle, true))
 518                return true;
 519
 520Fail:
 521        return false;
 522}
 523
 524static bool smu_v11_0_i2c_bus_unlock(struct i2c_adapter *control)
 525{
 526        struct amdgpu_device *adev = to_amdgpu_device(control);
 527
 528        /* Send  PPSMC_MSG_RequestI2CBus */
 529        if (!adev->powerplay.pp_funcs->smu_i2c_bus_access)
 530                goto Fail;
 531
 532        /* Send  PPSMC_MSG_ReleaseI2CBus */
 533        if (!adev->powerplay.pp_funcs->smu_i2c_bus_access(adev->powerplay.pp_handle,
 534                                                             false))
 535                return true;
 536
 537Fail:
 538        return false;
 539}
 540
 541/***************************** EEPROM I2C GLUE ****************************/
 542
 543static uint32_t smu_v11_0_i2c_eeprom_read_data(struct i2c_adapter *control,
 544                                               uint8_t address,
 545                                               uint8_t *data,
 546                                               uint32_t numbytes)
 547{
 548        uint32_t  ret = 0;
 549
 550        /* First 2 bytes are dummy write to set EEPROM address */
 551        ret = smu_v11_0_i2c_transmit(control, address, data, 2, I2C_NO_STOP);
 552        if (ret != I2C_OK)
 553                goto Fail;
 554
 555        /* Now read data starting with that address */
 556        ret = smu_v11_0_i2c_receive(control, address, data + 2, numbytes - 2,
 557                                    I2C_RESTART);
 558
 559Fail:
 560        if (ret != I2C_OK)
 561                DRM_ERROR("ReadData() - I2C error occurred :%x", ret);
 562
 563        return ret;
 564}
 565
 566static uint32_t smu_v11_0_i2c_eeprom_write_data(struct i2c_adapter *control,
 567                                                uint8_t address,
 568                                                uint8_t *data,
 569                                                uint32_t numbytes)
 570{
 571        uint32_t  ret;
 572
 573        ret = smu_v11_0_i2c_transmit(control, address, data, numbytes, 0);
 574
 575        if (ret != I2C_OK)
 576                DRM_ERROR("WriteI2CData() - I2C error occurred :%x", ret);
 577        else
 578                /*
 579                 * According to EEPROM spec there is a MAX of 10 ms required for
 580                 * EEPROM to flush internal RX buffer after STOP was issued at the
 581                 * end of write transaction. During this time the EEPROM will not be
 582                 * responsive to any more commands - so wait a bit more.
 583                 *
 584                 * TODO Improve to wait for first ACK for slave address after
 585                 * internal write cycle done.
 586                 */
 587                msleep(10);
 588
 589        return ret;
 590
 591}
 592
 593static void lock_bus(struct i2c_adapter *i2c, unsigned int flags)
 594{
 595        struct amdgpu_ras_eeprom_control *control = to_eeprom_control(i2c);
 596
 597        if (!smu_v11_0_i2c_bus_lock(i2c)) {
 598                DRM_ERROR("Failed to lock the bus from SMU");
 599                return;
 600        }
 601
 602        control->bus_locked = true;
 603}
 604
 605static int trylock_bus(struct i2c_adapter *i2c, unsigned int flags)
 606{
 607        WARN_ONCE(1, "This operation not supposed to run in atomic context!");
 608        return false;
 609}
 610
 611static void unlock_bus(struct i2c_adapter *i2c, unsigned int flags)
 612{
 613        struct amdgpu_ras_eeprom_control *control = to_eeprom_control(i2c);
 614
 615        if (!smu_v11_0_i2c_bus_unlock(i2c)) {
 616                DRM_ERROR("Failed to unlock the bus from SMU");
 617                return;
 618        }
 619
 620        control->bus_locked = false;
 621}
 622
 623static const struct i2c_lock_operations smu_v11_0_i2c_i2c_lock_ops = {
 624        .lock_bus = lock_bus,
 625        .trylock_bus = trylock_bus,
 626        .unlock_bus = unlock_bus,
 627};
 628
 629static int smu_v11_0_i2c_eeprom_i2c_xfer(struct i2c_adapter *i2c_adap,
 630                              struct i2c_msg *msgs, int num)
 631{
 632        int i, ret;
 633        struct amdgpu_ras_eeprom_control *control = to_eeprom_control(i2c_adap);
 634
 635        if (!control->bus_locked) {
 636                DRM_ERROR("I2C bus unlocked, stopping transaction!");
 637                return -EIO;
 638        }
 639
 640        smu_v11_0_i2c_init(i2c_adap);
 641
 642        for (i = 0; i < num; i++) {
 643                if (msgs[i].flags & I2C_M_RD)
 644                        ret = smu_v11_0_i2c_eeprom_read_data(i2c_adap,
 645                                                        (uint8_t)msgs[i].addr,
 646                                                        msgs[i].buf, msgs[i].len);
 647                else
 648                        ret = smu_v11_0_i2c_eeprom_write_data(i2c_adap,
 649                                                         (uint8_t)msgs[i].addr,
 650                                                         msgs[i].buf, msgs[i].len);
 651
 652                if (ret != I2C_OK) {
 653                        num = -EIO;
 654                        break;
 655                }
 656        }
 657
 658        smu_v11_0_i2c_fini(i2c_adap);
 659        return num;
 660}
 661
 662static u32 smu_v11_0_i2c_eeprom_i2c_func(struct i2c_adapter *adap)
 663{
 664        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 665}
 666
 667
 668static const struct i2c_algorithm smu_v11_0_i2c_eeprom_i2c_algo = {
 669        .master_xfer = smu_v11_0_i2c_eeprom_i2c_xfer,
 670        .functionality = smu_v11_0_i2c_eeprom_i2c_func,
 671};
 672
 673int smu_v11_0_i2c_eeprom_control_init(struct i2c_adapter *control)
 674{
 675        struct amdgpu_device *adev = to_amdgpu_device(control);
 676        int res;
 677
 678        control->owner = THIS_MODULE;
 679        control->class = I2C_CLASS_SPD;
 680        control->dev.parent = &adev->pdev->dev;
 681        control->algo = &smu_v11_0_i2c_eeprom_i2c_algo;
 682        snprintf(control->name, sizeof(control->name), "RAS EEPROM");
 683        control->lock_ops = &smu_v11_0_i2c_i2c_lock_ops;
 684
 685        res = i2c_add_adapter(control);
 686        if (res)
 687                DRM_ERROR("Failed to register hw i2c, err: %d\n", res);
 688
 689        return res;
 690}
 691
 692void smu_v11_0_i2c_eeprom_control_fini(struct i2c_adapter *control)
 693{
 694        i2c_del_adapter(control);
 695}
 696
 697/*
 698 * Keep this for future unit test if bugs arise
 699 */
 700#if 0
 701#define I2C_TARGET_ADDR 0xA0
 702
 703bool smu_v11_0_i2c_test_bus(struct i2c_adapter *control)
 704{
 705
 706        uint32_t ret = I2C_OK;
 707        uint8_t data[6] = {0xf, 0, 0xde, 0xad, 0xbe, 0xef};
 708
 709
 710        DRM_INFO("Begin");
 711
 712        if (!smu_v11_0_i2c_bus_lock(control)) {
 713                DRM_ERROR("Failed to lock the bus!.");
 714                return false;
 715        }
 716
 717        smu_v11_0_i2c_init(control);
 718
 719        /* Write 0xde to address 0x0000 on the EEPROM */
 720        ret = smu_v11_0_i2c_eeprom_write_data(control, I2C_TARGET_ADDR, data, 6);
 721
 722        ret = smu_v11_0_i2c_eeprom_read_data(control, I2C_TARGET_ADDR, data, 6);
 723
 724        smu_v11_0_i2c_fini(control);
 725
 726        smu_v11_0_i2c_bus_unlock(control);
 727
 728
 729        DRM_INFO("End");
 730        return true;
 731}
 732#endif
 733