drivers/gpu/drm/amd/amdgpu/amdgpu_atpx_handler.c

   1 /*
   2  * Copyright (c) 2010 Red Hat Inc.
   3  * Author : Dave Airlie <airlied@redhat.com>
   4  *
   5  * Licensed under GPLv2
   6  *
   7  * ATPX support for both Intel/ATI
   8  */
   9 #include <linux/vga_switcheroo.h>
  10 #include <linux/slab.h>
  11 #include <linux/acpi.h>
  12 #include <linux/pci.h>
  13
  14 #include "amd_acpi.h"
  15
  16 struct amdgpu_atpx_functions {
  17         bool px_params;
  18         bool power_cntl;
  19         bool disp_mux_cntl;
  20         bool i2c_mux_cntl;
  21         bool switch_start;
  22         bool switch_end;
  23         bool disp_connectors_mapping;
  24         bool disp_detetion_ports;
  25 };
  26
  27 struct amdgpu_atpx {
  28         acpi_handle handle;
  29         struct amdgpu_atpx_functions functions;
  30 };
  31
  32 static struct amdgpu_atpx_priv {
  33         bool atpx_detected;
  34         /* handle for device - and atpx */
  35         acpi_handle dhandle;
  36         acpi_handle other_handle;
  37         struct amdgpu_atpx atpx;
  38 } amdgpu_atpx_priv;
  39
  40 struct atpx_verify_interface {
  41         u16 size;               /* structure size in bytes (includes size field) */
  42         u16 version;            /* version */
  43         u32 function_bits;      /* supported functions bit vector */
  44 } __packed;
  45
  46 struct atpx_px_params {
  47         u16 size;               /* structure size in bytes (includes size field) */
  48         u32 valid_flags;        /* which flags are valid */
  49         u32 flags;              /* flags */
  50 } __packed;
  51
  52 struct atpx_power_control {
  53         u16 size;
  54         u8 dgpu_state;
  55 } __packed;
  56
  57 struct atpx_mux {
  58         u16 size;
  59         u16 mux;
  60 } __packed;
  61
  62 bool amdgpu_has_atpx(void) {
  63         return amdgpu_atpx_priv.atpx_detected;
  64 }
  65
  66 /**
  67  * amdgpu_atpx_call - call an ATPX method
  68  *
  69  * @handle: acpi handle
  70  * @function: the ATPX function to execute
  71  * @params: ATPX function params
  72  *
  73  * Executes the requested ATPX function (all asics).
  74  * Returns a pointer to the acpi output buffer.
  75  */
  76 static union acpi_object *amdgpu_atpx_call(acpi_handle handle, int function,
  77                                            struct acpi_buffer *params)
  78 {
  79         acpi_status status;
  80         union acpi_object atpx_arg_elements[2];
  81         struct acpi_object_list atpx_arg;
  82         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  83
  84         atpx_arg.count = 2;
  85         atpx_arg.pointer = &atpx_arg_elements[0];
  86
  87         atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
  88         atpx_arg_elements[0].integer.value = function;
  89
  90         if (params) {
  91                 atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
  92                 atpx_arg_elements[1].buffer.length = params->length;
  93                 atpx_arg_elements[1].buffer.pointer = params->pointer;
  94         } else {
  95                 /* We need a second fake parameter */
  96                 atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
  97                 atpx_arg_elements[1].integer.value = 0;
  98         }
  99
 100         status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);
 101
 102         /* Fail only if calling the method fails and ATPX is supported */
 103         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 104                 printk("failed to evaluate ATPX got %s\n",
 105                        acpi_format_exception(status));
 106                 kfree(buffer.pointer);
 107                 return NULL;
 108         }
 109
 110         return buffer.pointer;
 111 }
 112
 113 /**
 114  * amdgpu_atpx_parse_functions - parse supported functions
 115  *
 116  * @f: supported functions struct
 117  * @mask: supported functions mask from ATPX
 118  *
 119  * Use the supported functions mask from ATPX function
 120  * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
 121  * are supported (all asics).
 122  */
 123 static void amdgpu_atpx_parse_functions(struct amdgpu_atpx_functions *f, u32 mask)
 124 {
 125         f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
 126         f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
 127         f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
 128         f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
 129         f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
 130         f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
 131         f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
 132         f->disp_detetion_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
 133 }
 134
 135 /**
 136  * amdgpu_atpx_validate_functions - validate ATPX functions
 137  *
 138  * @atpx: amdgpu atpx struct
 139  *
 140  * Validate that required functions are enabled (all asics).
 141  * returns 0 on success, error on failure.
 142  */
 143 static int amdgpu_atpx_validate(struct amdgpu_atpx *atpx)
 144 {
 145         /* make sure required functions are enabled */
 146         /* dGPU power control is required */
 147         if (atpx->functions.power_cntl == false) {
 148                 printk("ATPX dGPU power cntl not present, forcing\n");
 149                 atpx->functions.power_cntl = true;
 150         }
 151
 152         if (atpx->functions.px_params) {
 153                 union acpi_object *info;
 154                 struct atpx_px_params output;
 155                 size_t size;
 156                 u32 valid_bits;
 157
 158                 info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
 159                 if (!info)
 160                         return -EIO;
 161
 162                 memset(&output, 0, sizeof(output));
 163
 164                 size = *(u16 *) info->buffer.pointer;
 165                 if (size < 10) {
 166                         printk("ATPX buffer is too small: %zu\n", size);
 167                         kfree(info);
 168                         return -EINVAL;
 169                 }
 170                 size = min(sizeof(output), size);
 171
 172                 memcpy(&output, info->buffer.pointer, size);
 173
 174                 valid_bits = output.flags & output.valid_flags;
 175                 /* if separate mux flag is set, mux controls are required */
 176                 if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
 177                         atpx->functions.i2c_mux_cntl = true;
 178                         atpx->functions.disp_mux_cntl = true;
 179                 }
 180                 /* if any outputs are muxed, mux controls are required */
 181                 if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
 182                                   ATPX_TV_SIGNAL_MUXED |
 183                                   ATPX_DFP_SIGNAL_MUXED))
 184                         atpx->functions.disp_mux_cntl = true;
 185
 186                 kfree(info);
 187         }
 188         return 0;
 189 }
 190
 191 /**
 192  * amdgpu_atpx_verify_interface - verify ATPX
 193  *
 194  * @atpx: amdgpu atpx struct
 195  *
 196  * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
 197  * to initialize ATPX and determine what features are supported
 198  * (all asics).
 199  * returns 0 on success, error on failure.
 200  */
 201 static int amdgpu_atpx_verify_interface(struct amdgpu_atpx *atpx)
 202 {
 203         union acpi_object *info;
 204         struct atpx_verify_interface output;
 205         size_t size;
 206         int err = 0;
 207
 208         info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
 209         if (!info)
 210                 return -EIO;
 211
 212         memset(&output, 0, sizeof(output));
 213
 214         size = *(u16 *) info->buffer.pointer;
 215         if (size < 8) {
 216                 printk("ATPX buffer is too small: %zu\n", size);
 217                 err = -EINVAL;
 218                 goto out;
 219         }
 220         size = min(sizeof(output), size);
 221
 222         memcpy(&output, info->buffer.pointer, size);
 223
 224         /* TODO: check version? */
 225         printk("ATPX version %u, functions 0x%08x\n",
 226                output.version, output.function_bits);
 227
 228         amdgpu_atpx_parse_functions(&atpx->functions, output.function_bits);
 229
 230 out:
 231         kfree(info);
 232         return err;
 233 }
 234
 235 /**
 236  * amdgpu_atpx_set_discrete_state - power up/down discrete GPU
 237  *
 238  * @atpx: atpx info struct
 239  * @state: discrete GPU state (0 = power down, 1 = power up)
 240  *
 241  * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
 242  * power down/up the discrete GPU (all asics).
 243  * Returns 0 on success, error on failure.
 244  */
 245 static int amdgpu_atpx_set_discrete_state(struct amdgpu_atpx *atpx, u8 state)
 246 {
 247         struct acpi_buffer params;
 248         union acpi_object *info;
 249         struct atpx_power_control input;
 250
 251         if (atpx->functions.power_cntl) {
 252                 input.size = 3;
 253                 input.dgpu_state = state;
 254                 params.length = input.size;
 255                 params.pointer = &input;
 256                 info = amdgpu_atpx_call(atpx->handle,
 257                                         ATPX_FUNCTION_POWER_CONTROL,
 258                                         &params);
 259                 if (!info)
 260                         return -EIO;
 261                 kfree(info);
 262         }
 263         return 0;
 264 }
 265
 266 /**
 267  * amdgpu_atpx_switch_disp_mux - switch display mux
 268  *
 269  * @atpx: atpx info struct
 270  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 271  *
 272  * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
 273  * switch the display mux between the discrete GPU and integrated GPU
 274  * (all asics).
 275  * Returns 0 on success, error on failure.
 276  */
 277 static int amdgpu_atpx_switch_disp_mux(struct amdgpu_atpx *atpx, u16 mux_id)
 278 {
 279         struct acpi_buffer params;
 280         union acpi_object *info;
 281         struct atpx_mux input;
 282
 283         if (atpx->functions.disp_mux_cntl) {
 284                 input.size = 4;
 285                 input.mux = mux_id;
 286                 params.length = input.size;
 287                 params.pointer = &input;
 288                 info = amdgpu_atpx_call(atpx->handle,
 289                                         ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
 290                                         &params);
 291                 if (!info)
 292                         return -EIO;
 293                 kfree(info);
 294         }
 295         return 0;
 296 }
 297
 298 /**
 299  * amdgpu_atpx_switch_i2c_mux - switch i2c/hpd mux
 300  *
 301  * @atpx: atpx info struct
 302  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 303  *
 304  * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
 305  * switch the i2c/hpd mux between the discrete GPU and integrated GPU
 306  * (all asics).
 307  * Returns 0 on success, error on failure.
 308  */
 309 static int amdgpu_atpx_switch_i2c_mux(struct amdgpu_atpx *atpx, u16 mux_id)
 310 {
 311         struct acpi_buffer params;
 312         union acpi_object *info;
 313         struct atpx_mux input;
 314
 315         if (atpx->functions.i2c_mux_cntl) {
 316                 input.size = 4;
 317                 input.mux = mux_id;
 318                 params.length = input.size;
 319                 params.pointer = &input;
 320                 info = amdgpu_atpx_call(atpx->handle,
 321                                         ATPX_FUNCTION_I2C_MUX_CONTROL,
 322                                         &params);
 323                 if (!info)
 324                         return -EIO;
 325                 kfree(info);
 326         }
 327         return 0;
 328 }
 329
 330 /**
 331  * amdgpu_atpx_switch_start - notify the sbios of a GPU switch
 332  *
 333  * @atpx: atpx info struct
 334  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 335  *
 336  * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
 337  * function to notify the sbios that a switch between the discrete GPU and
 338  * integrated GPU has begun (all asics).
 339  * Returns 0 on success, error on failure.
 340  */
 341 static int amdgpu_atpx_switch_start(struct amdgpu_atpx *atpx, u16 mux_id)
 342 {
 343         struct acpi_buffer params;
 344         union acpi_object *info;
 345         struct atpx_mux input;
 346
 347         if (atpx->functions.switch_start) {
 348                 input.size = 4;
 349                 input.mux = mux_id;
 350                 params.length = input.size;
 351                 params.pointer = &input;
 352                 info = amdgpu_atpx_call(atpx->handle,
 353                                         ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
 354                                         &params);
 355                 if (!info)
 356                         return -EIO;
 357                 kfree(info);
 358         }
 359         return 0;
 360 }
 361
 362 /**
 363  * amdgpu_atpx_switch_end - notify the sbios of a GPU switch
 364  *
 365  * @atpx: atpx info struct
 366  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 367  *
 368  * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
 369  * function to notify the sbios that a switch between the discrete GPU and
 370  * integrated GPU has ended (all asics).
 371  * Returns 0 on success, error on failure.
 372  */
 373 static int amdgpu_atpx_switch_end(struct amdgpu_atpx *atpx, u16 mux_id)
 374 {
 375         struct acpi_buffer params;
 376         union acpi_object *info;
 377         struct atpx_mux input;
 378
 379         if (atpx->functions.switch_end) {
 380                 input.size = 4;
 381                 input.mux = mux_id;
 382                 params.length = input.size;
 383                 params.pointer = &input;
 384                 info = amdgpu_atpx_call(atpx->handle,
 385                                         ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
 386                                         &params);
 387                 if (!info)
 388                         return -EIO;
 389                 kfree(info);
 390         }
 391         return 0;
 392 }
 393
 394 /**
 395  * amdgpu_atpx_switchto - switch to the requested GPU
 396  *
 397  * @id: GPU to switch to
 398  *
 399  * Execute the necessary ATPX functions to switch between the discrete GPU and
 400  * integrated GPU (all asics).
 401  * Returns 0 on success, error on failure.
 402  */
 403 static int amdgpu_atpx_switchto(enum vga_switcheroo_client_id id)
 404 {
 405         u16 gpu_id;
 406
 407         if (id == VGA_SWITCHEROO_IGD)
 408                 gpu_id = ATPX_INTEGRATED_GPU;
 409         else
 410                 gpu_id = ATPX_DISCRETE_GPU;
 411
 412         amdgpu_atpx_switch_start(&amdgpu_atpx_priv.atpx, gpu_id);
 413         amdgpu_atpx_switch_disp_mux(&amdgpu_atpx_priv.atpx, gpu_id);
 414         amdgpu_atpx_switch_i2c_mux(&amdgpu_atpx_priv.atpx, gpu_id);
 415         amdgpu_atpx_switch_end(&amdgpu_atpx_priv.atpx, gpu_id);
 416
 417         return 0;
 418 }
 419
 420 /**
 421  * amdgpu_atpx_power_state - power down/up the requested GPU
 422  *
 423  * @id: GPU to power down/up
 424  * @state: requested power state (0 = off, 1 = on)
 425  *
 426  * Execute the necessary ATPX function to power down/up the discrete GPU
 427  * (all asics).
 428  * Returns 0 on success, error on failure.
 429  */
 430 static int amdgpu_atpx_power_state(enum vga_switcheroo_client_id id,
 431                                    enum vga_switcheroo_state state)
 432 {
 433         /* on w500 ACPI can't change intel gpu state */
 434         if (id == VGA_SWITCHEROO_IGD)
 435                 return 0;
 436
 437         amdgpu_atpx_set_discrete_state(&amdgpu_atpx_priv.atpx, state);
 438         return 0;
 439 }
 440
 441 /**
 442  * amdgpu_atpx_pci_probe_handle - look up the ATPX handle
 443  *
 444  * @pdev: pci device
 445  *
 446  * Look up the ATPX handles (all asics).
 447  * Returns true if the handles are found, false if not.
 448  */
 449 static bool amdgpu_atpx_pci_probe_handle(struct pci_dev *pdev)
 450 {
 451         acpi_handle dhandle, atpx_handle;
 452         acpi_status status;
 453
 454         dhandle = ACPI_HANDLE(&pdev->dev);
 455         if (!dhandle)
 456                 return false;
 457
 458         status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
 459         if (ACPI_FAILURE(status)) {
 460                 amdgpu_atpx_priv.other_handle = dhandle;
 461                 return false;
 462         }
 463         amdgpu_atpx_priv.dhandle = dhandle;
 464         amdgpu_atpx_priv.atpx.handle = atpx_handle;
 465         return true;
 466 }
 467
 468 /**
 469  * amdgpu_atpx_init - verify the ATPX interface
 470  *
 471  * Verify the ATPX interface (all asics).
 472  * Returns 0 on success, error on failure.
 473  */
 474 static int amdgpu_atpx_init(void)
 475 {
 476         int r;
 477
 478         /* set up the ATPX handle */
 479         r = amdgpu_atpx_verify_interface(&amdgpu_atpx_priv.atpx);
 480         if (r)
 481                 return r;
 482
 483         /* validate the atpx setup */
 484         r = amdgpu_atpx_validate(&amdgpu_atpx_priv.atpx);
 485         if (r)
 486                 return r;
 487
 488         return 0;
 489 }
 490
 491 /**
 492  * amdgpu_atpx_get_client_id - get the client id
 493  *
 494  * @pdev: pci device
 495  *
 496  * look up whether we are the integrated or discrete GPU (all asics).
 497  * Returns the client id.
 498  */
 499 static int amdgpu_atpx_get_client_id(struct pci_dev *pdev)
 500 {
 501         if (amdgpu_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
 502                 return VGA_SWITCHEROO_IGD;
 503         else
 504                 return VGA_SWITCHEROO_DIS;
 505 }
 506
 507 static const struct vga_switcheroo_handler amdgpu_atpx_handler = {
 508         .switchto = amdgpu_atpx_switchto,
 509         .power_state = amdgpu_atpx_power_state,
 510         .init = amdgpu_atpx_init,
 511         .get_client_id = amdgpu_atpx_get_client_id,
 512 };
 513
 514 /**
 515  * amdgpu_atpx_detect - detect whether we have PX
 516  *
 517  * Check if we have a PX system (all asics).
 518  * Returns true if we have a PX system, false if not.
 519  */
 520 static bool amdgpu_atpx_detect(void)
 521 {
 522         char acpi_method_name[255] = { 0 };
 523         struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
 524         struct pci_dev *pdev = NULL;
 525         bool has_atpx = false;
 526         int vga_count = 0;
 527
 528         while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
 529                 vga_count++;
 530
 531                 has_atpx |= (amdgpu_atpx_pci_probe_handle(pdev) == true);
 532         }
 533
 534         while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
 535                 vga_count++;
 536
 537                 has_atpx |= (amdgpu_atpx_pci_probe_handle(pdev) == true);
 538         }
 539
 540         if (has_atpx && vga_count == 2) {
 541                 acpi_get_name(amdgpu_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
 542                 printk(KERN_INFO "vga_switcheroo: detected switching method %s handle\n",
 543                        acpi_method_name);
 544                 amdgpu_atpx_priv.atpx_detected = true;
 545                 return true;
 546         }
 547         return false;
 548 }
 549
 550 /**
 551  * amdgpu_register_atpx_handler - register with vga_switcheroo
 552  *
 553  * Register the PX callbacks with vga_switcheroo (all asics).
 554  */
 555 void amdgpu_register_atpx_handler(void)
 556 {
 557         bool r;
 558         enum vga_switcheroo_handler_flags_t handler_flags = 0;
 559
 560         /* detect if we have any ATPX + 2 VGA in the system */
 561         r = amdgpu_atpx_detect();
 562         if (!r)
 563                 return;
 564
 565         vga_switcheroo_register_handler(&amdgpu_atpx_handler, handler_flags);
 566 }
 567
 568 /**
 569  * amdgpu_unregister_atpx_handler - unregister with vga_switcheroo
 570  *
 571  * Unregister the PX callbacks with vga_switcheroo (all asics).
 572  */
 573 void amdgpu_unregister_atpx_handler(void)
 574 {
 575         vga_switcheroo_unregister_handler();
 576 }