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 "amdgpu_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         atpx->functions.power_cntl = true;
 148
 149         if (atpx->functions.px_params) {
 150                 union acpi_object *info;
 151                 struct atpx_px_params output;
 152                 size_t size;
 153                 u32 valid_bits;
 154
 155                 info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
 156                 if (!info)
 157                         return -EIO;
 158
 159                 memset(&output, 0, sizeof(output));
 160
 161                 size = *(u16 *) info->buffer.pointer;
 162                 if (size < 10) {
 163                         printk("ATPX buffer is too small: %zu\n", size);
 164                         kfree(info);
 165                         return -EINVAL;
 166                 }
 167                 size = min(sizeof(output), size);
 168
 169                 memcpy(&output, info->buffer.pointer, size);
 170
 171                 valid_bits = output.flags & output.valid_flags;
 172                 /* if separate mux flag is set, mux controls are required */
 173                 if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
 174                         atpx->functions.i2c_mux_cntl = true;
 175                         atpx->functions.disp_mux_cntl = true;
 176                 }
 177                 /* if any outputs are muxed, mux controls are required */
 178                 if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
 179                                   ATPX_TV_SIGNAL_MUXED |
 180                                   ATPX_DFP_SIGNAL_MUXED))
 181                         atpx->functions.disp_mux_cntl = true;
 182
 183                 kfree(info);
 184         }
 185         return 0;
 186 }
 187
 188 /**
 189  * amdgpu_atpx_verify_interface - verify ATPX
 190  *
 191  * @atpx: amdgpu atpx struct
 192  *
 193  * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
 194  * to initialize ATPX and determine what features are supported
 195  * (all asics).
 196  * returns 0 on success, error on failure.
 197  */
 198 static int amdgpu_atpx_verify_interface(struct amdgpu_atpx *atpx)
 199 {
 200         union acpi_object *info;
 201         struct atpx_verify_interface output;
 202         size_t size;
 203         int err = 0;
 204
 205         info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
 206         if (!info)
 207                 return -EIO;
 208
 209         memset(&output, 0, sizeof(output));
 210
 211         size = *(u16 *) info->buffer.pointer;
 212         if (size < 8) {
 213                 printk("ATPX buffer is too small: %zu\n", size);
 214                 err = -EINVAL;
 215                 goto out;
 216         }
 217         size = min(sizeof(output), size);
 218
 219         memcpy(&output, info->buffer.pointer, size);
 220
 221         /* TODO: check version? */
 222         printk("ATPX version %u, functions 0x%08x\n",
 223                output.version, output.function_bits);
 224
 225         amdgpu_atpx_parse_functions(&atpx->functions, output.function_bits);
 226
 227 out:
 228         kfree(info);
 229         return err;
 230 }
 231
 232 /**
 233  * amdgpu_atpx_set_discrete_state - power up/down discrete GPU
 234  *
 235  * @atpx: atpx info struct
 236  * @state: discrete GPU state (0 = power down, 1 = power up)
 237  *
 238  * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
 239  * power down/up the discrete GPU (all asics).
 240  * Returns 0 on success, error on failure.
 241  */
 242 static int amdgpu_atpx_set_discrete_state(struct amdgpu_atpx *atpx, u8 state)
 243 {
 244         struct acpi_buffer params;
 245         union acpi_object *info;
 246         struct atpx_power_control input;
 247
 248         if (atpx->functions.power_cntl) {
 249                 input.size = 3;
 250                 input.dgpu_state = state;
 251                 params.length = input.size;
 252                 params.pointer = &input;
 253                 info = amdgpu_atpx_call(atpx->handle,
 254                                         ATPX_FUNCTION_POWER_CONTROL,
 255                                         &params);
 256                 if (!info)
 257                         return -EIO;
 258                 kfree(info);
 259         }
 260         return 0;
 261 }
 262
 263 /**
 264  * amdgpu_atpx_switch_disp_mux - switch display mux
 265  *
 266  * @atpx: atpx info struct
 267  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 268  *
 269  * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
 270  * switch the display mux between the discrete GPU and integrated GPU
 271  * (all asics).
 272  * Returns 0 on success, error on failure.
 273  */
 274 static int amdgpu_atpx_switch_disp_mux(struct amdgpu_atpx *atpx, u16 mux_id)
 275 {
 276         struct acpi_buffer params;
 277         union acpi_object *info;
 278         struct atpx_mux input;
 279
 280         if (atpx->functions.disp_mux_cntl) {
 281                 input.size = 4;
 282                 input.mux = mux_id;
 283                 params.length = input.size;
 284                 params.pointer = &input;
 285                 info = amdgpu_atpx_call(atpx->handle,
 286                                         ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
 287                                         &params);
 288                 if (!info)
 289                         return -EIO;
 290                 kfree(info);
 291         }
 292         return 0;
 293 }
 294
 295 /**
 296  * amdgpu_atpx_switch_i2c_mux - switch i2c/hpd mux
 297  *
 298  * @atpx: atpx info struct
 299  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 300  *
 301  * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
 302  * switch the i2c/hpd mux between the discrete GPU and integrated GPU
 303  * (all asics).
 304  * Returns 0 on success, error on failure.
 305  */
 306 static int amdgpu_atpx_switch_i2c_mux(struct amdgpu_atpx *atpx, u16 mux_id)
 307 {
 308         struct acpi_buffer params;
 309         union acpi_object *info;
 310         struct atpx_mux input;
 311
 312         if (atpx->functions.i2c_mux_cntl) {
 313                 input.size = 4;
 314                 input.mux = mux_id;
 315                 params.length = input.size;
 316                 params.pointer = &input;
 317                 info = amdgpu_atpx_call(atpx->handle,
 318                                         ATPX_FUNCTION_I2C_MUX_CONTROL,
 319                                         &params);
 320                 if (!info)
 321                         return -EIO;
 322                 kfree(info);
 323         }
 324         return 0;
 325 }
 326
 327 /**
 328  * amdgpu_atpx_switch_start - notify the sbios of a GPU switch
 329  *
 330  * @atpx: atpx info struct
 331  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 332  *
 333  * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
 334  * function to notify the sbios that a switch between the discrete GPU and
 335  * integrated GPU has begun (all asics).
 336  * Returns 0 on success, error on failure.
 337  */
 338 static int amdgpu_atpx_switch_start(struct amdgpu_atpx *atpx, u16 mux_id)
 339 {
 340         struct acpi_buffer params;
 341         union acpi_object *info;
 342         struct atpx_mux input;
 343
 344         if (atpx->functions.switch_start) {
 345                 input.size = 4;
 346                 input.mux = mux_id;
 347                 params.length = input.size;
 348                 params.pointer = &input;
 349                 info = amdgpu_atpx_call(atpx->handle,
 350                                         ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
 351                                         &params);
 352                 if (!info)
 353                         return -EIO;
 354                 kfree(info);
 355         }
 356         return 0;
 357 }
 358
 359 /**
 360  * amdgpu_atpx_switch_end - notify the sbios of a GPU switch
 361  *
 362  * @atpx: atpx info struct
 363  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 364  *
 365  * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
 366  * function to notify the sbios that a switch between the discrete GPU and
 367  * integrated GPU has ended (all asics).
 368  * Returns 0 on success, error on failure.
 369  */
 370 static int amdgpu_atpx_switch_end(struct amdgpu_atpx *atpx, u16 mux_id)
 371 {
 372         struct acpi_buffer params;
 373         union acpi_object *info;
 374         struct atpx_mux input;
 375
 376         if (atpx->functions.switch_end) {
 377                 input.size = 4;
 378                 input.mux = mux_id;
 379                 params.length = input.size;
 380                 params.pointer = &input;
 381                 info = amdgpu_atpx_call(atpx->handle,
 382                                         ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
 383                                         &params);
 384                 if (!info)
 385                         return -EIO;
 386                 kfree(info);
 387         }
 388         return 0;
 389 }
 390
 391 /**
 392  * amdgpu_atpx_switchto - switch to the requested GPU
 393  *
 394  * @id: GPU to switch to
 395  *
 396  * Execute the necessary ATPX functions to switch between the discrete GPU and
 397  * integrated GPU (all asics).
 398  * Returns 0 on success, error on failure.
 399  */
 400 static int amdgpu_atpx_switchto(enum vga_switcheroo_client_id id)
 401 {
 402         u16 gpu_id;
 403
 404         if (id == VGA_SWITCHEROO_IGD)
 405                 gpu_id = ATPX_INTEGRATED_GPU;
 406         else
 407                 gpu_id = ATPX_DISCRETE_GPU;
 408
 409         amdgpu_atpx_switch_start(&amdgpu_atpx_priv.atpx, gpu_id);
 410         amdgpu_atpx_switch_disp_mux(&amdgpu_atpx_priv.atpx, gpu_id);
 411         amdgpu_atpx_switch_i2c_mux(&amdgpu_atpx_priv.atpx, gpu_id);
 412         amdgpu_atpx_switch_end(&amdgpu_atpx_priv.atpx, gpu_id);
 413
 414         return 0;
 415 }
 416
 417 /**
 418  * amdgpu_atpx_power_state - power down/up the requested GPU
 419  *
 420  * @id: GPU to power down/up
 421  * @state: requested power state (0 = off, 1 = on)
 422  *
 423  * Execute the necessary ATPX function to power down/up the discrete GPU
 424  * (all asics).
 425  * Returns 0 on success, error on failure.
 426  */
 427 static int amdgpu_atpx_power_state(enum vga_switcheroo_client_id id,
 428                                    enum vga_switcheroo_state state)
 429 {
 430         /* on w500 ACPI can't change intel gpu state */
 431         if (id == VGA_SWITCHEROO_IGD)
 432                 return 0;
 433
 434         amdgpu_atpx_set_discrete_state(&amdgpu_atpx_priv.atpx, state);
 435         return 0;
 436 }
 437
 438 /**
 439  * amdgpu_atpx_pci_probe_handle - look up the ATPX handle
 440  *
 441  * @pdev: pci device
 442  *
 443  * Look up the ATPX handles (all asics).
 444  * Returns true if the handles are found, false if not.
 445  */
 446 static bool amdgpu_atpx_pci_probe_handle(struct pci_dev *pdev)
 447 {
 448         acpi_handle dhandle, atpx_handle;
 449         acpi_status status;
 450
 451         dhandle = ACPI_HANDLE(&pdev->dev);
 452         if (!dhandle)
 453                 return false;
 454
 455         status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
 456         if (ACPI_FAILURE(status)) {
 457                 amdgpu_atpx_priv.other_handle = dhandle;
 458                 return false;
 459         }
 460         amdgpu_atpx_priv.dhandle = dhandle;
 461         amdgpu_atpx_priv.atpx.handle = atpx_handle;
 462         return true;
 463 }
 464
 465 /**
 466  * amdgpu_atpx_init - verify the ATPX interface
 467  *
 468  * Verify the ATPX interface (all asics).
 469  * Returns 0 on success, error on failure.
 470  */
 471 static int amdgpu_atpx_init(void)
 472 {
 473         int r;
 474
 475         /* set up the ATPX handle */
 476         r = amdgpu_atpx_verify_interface(&amdgpu_atpx_priv.atpx);
 477         if (r)
 478                 return r;
 479
 480         /* validate the atpx setup */
 481         r = amdgpu_atpx_validate(&amdgpu_atpx_priv.atpx);
 482         if (r)
 483                 return r;
 484
 485         return 0;
 486 }
 487
 488 /**
 489  * amdgpu_atpx_get_client_id - get the client id
 490  *
 491  * @pdev: pci device
 492  *
 493  * look up whether we are the integrated or discrete GPU (all asics).
 494  * Returns the client id.
 495  */
 496 static int amdgpu_atpx_get_client_id(struct pci_dev *pdev)
 497 {
 498         if (amdgpu_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
 499                 return VGA_SWITCHEROO_IGD;
 500         else
 501                 return VGA_SWITCHEROO_DIS;
 502 }
 503
 504 static const struct vga_switcheroo_handler amdgpu_atpx_handler = {
 505         .switchto = amdgpu_atpx_switchto,
 506         .power_state = amdgpu_atpx_power_state,
 507         .init = amdgpu_atpx_init,
 508         .get_client_id = amdgpu_atpx_get_client_id,
 509 };
 510
 511 /**
 512  * amdgpu_atpx_detect - detect whether we have PX
 513  *
 514  * Check if we have a PX system (all asics).
 515  * Returns true if we have a PX system, false if not.
 516  */
 517 static bool amdgpu_atpx_detect(void)
 518 {
 519         char acpi_method_name[255] = { 0 };
 520         struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
 521         struct pci_dev *pdev = NULL;
 522         bool has_atpx = false;
 523         int vga_count = 0;
 524
 525         while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
 526                 vga_count++;
 527
 528                 has_atpx |= (amdgpu_atpx_pci_probe_handle(pdev) == true);
 529         }
 530
 531         while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
 532                 vga_count++;
 533
 534                 has_atpx |= (amdgpu_atpx_pci_probe_handle(pdev) == true);
 535         }
 536
 537         if (has_atpx && vga_count == 2) {
 538                 acpi_get_name(amdgpu_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
 539                 printk(KERN_INFO "vga_switcheroo: detected switching method %s handle\n",
 540                        acpi_method_name);
 541                 amdgpu_atpx_priv.atpx_detected = true;
 542                 return true;
 543         }
 544         return false;
 545 }
 546
 547 /**
 548  * amdgpu_register_atpx_handler - register with vga_switcheroo
 549  *
 550  * Register the PX callbacks with vga_switcheroo (all asics).
 551  */
 552 void amdgpu_register_atpx_handler(void)
 553 {
 554         bool r;
 555
 556         /* detect if we have any ATPX + 2 VGA in the system */
 557         r = amdgpu_atpx_detect();
 558         if (!r)
 559                 return;
 560
 561         vga_switcheroo_register_handler(&amdgpu_atpx_handler);
 562 }
 563
 564 /**
 565  * amdgpu_unregister_atpx_handler - unregister with vga_switcheroo
 566  *
 567  * Unregister the PX callbacks with vga_switcheroo (all asics).
 568  */
 569 void amdgpu_unregister_atpx_handler(void)
 570 {
 571         vga_switcheroo_unregister_handler();
 572 }