drivers/gpu/drm/radeon/radeon_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 "radeon_acpi.h"
  15
  16 struct radeon_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 radeon_atpx {
  28         acpi_handle handle;
  29         struct radeon_atpx_functions functions;
  30 };
  31
  32 static struct radeon_atpx_priv {
  33         bool atpx_detected;
  34         /* handle for device - and atpx */
  35         acpi_handle dhandle;
  36         struct radeon_atpx atpx;
  37 } radeon_atpx_priv;
  38
  39 struct atpx_verify_interface {
  40         u16 size;               /* structure size in bytes (includes size field) */
  41         u16 version;            /* version */
  42         u32 function_bits;      /* supported functions bit vector */
  43 } __packed;
  44
  45 struct atpx_px_params {
  46         u16 size;               /* structure size in bytes (includes size field) */
  47         u32 valid_flags;        /* which flags are valid */
  48         u32 flags;              /* flags */
  49 } __packed;
  50
  51 struct atpx_power_control {
  52         u16 size;
  53         u8 dgpu_state;
  54 } __packed;
  55
  56 struct atpx_mux {
  57         u16 size;
  58         u16 mux;
  59 } __packed;
  60
  61 bool radeon_has_atpx(void) {
  62         return radeon_atpx_priv.atpx_detected;
  63 }
  64
  65 /**
  66  * radeon_atpx_call - call an ATPX method
  67  *
  68  * @handle: acpi handle
  69  * @function: the ATPX function to execute
  70  * @params: ATPX function params
  71  *
  72  * Executes the requested ATPX function (all asics).
  73  * Returns a pointer to the acpi output buffer.
  74  */
  75 static union acpi_object *radeon_atpx_call(acpi_handle handle, int function,
  76                                            struct acpi_buffer *params)
  77 {
  78         acpi_status status;
  79         union acpi_object atpx_arg_elements[2];
  80         struct acpi_object_list atpx_arg;
  81         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  82
  83         atpx_arg.count = 2;
  84         atpx_arg.pointer = &atpx_arg_elements[0];
  85
  86         atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
  87         atpx_arg_elements[0].integer.value = function;
  88
  89         if (params) {
  90                 atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
  91                 atpx_arg_elements[1].buffer.length = params->length;
  92                 atpx_arg_elements[1].buffer.pointer = params->pointer;
  93         } else {
  94                 /* We need a second fake parameter */
  95                 atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
  96                 atpx_arg_elements[1].integer.value = 0;
  97         }
  98
  99         status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);
 100
 101         /* Fail only if calling the method fails and ATPX is supported */
 102         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 103                 printk("failed to evaluate ATPX got %s\n",
 104                        acpi_format_exception(status));
 105                 kfree(buffer.pointer);
 106                 return NULL;
 107         }
 108
 109         return buffer.pointer;
 110 }
 111
 112 /**
 113  * radeon_atpx_parse_functions - parse supported functions
 114  *
 115  * @f: supported functions struct
 116  * @mask: supported functions mask from ATPX
 117  *
 118  * Use the supported functions mask from ATPX function
 119  * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
 120  * are supported (all asics).
 121  */
 122 static void radeon_atpx_parse_functions(struct radeon_atpx_functions *f, u32 mask)
 123 {
 124         f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
 125         f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
 126         f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
 127         f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
 128         f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
 129         f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
 130         f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
 131         f->disp_detetion_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
 132 }
 133
 134 /**
 135  * radeon_atpx_validate_functions - validate ATPX functions
 136  *
 137  * @atpx: radeon atpx struct
 138  *
 139  * Validate that required functions are enabled (all asics).
 140  * returns 0 on success, error on failure.
 141  */
 142 static int radeon_atpx_validate(struct radeon_atpx *atpx)
 143 {
 144         /* make sure required functions are enabled */
 145         /* dGPU power control is required */
 146         if (atpx->functions.power_cntl == false) {
 147                 printk("ATPX dGPU power cntl not present, forcing\n");
 148                 atpx->functions.power_cntl = true;
 149         }
 150
 151         if (atpx->functions.px_params) {
 152                 union acpi_object *info;
 153                 struct atpx_px_params output;
 154                 size_t size;
 155                 u32 valid_bits;
 156
 157                 info = radeon_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
 158                 if (!info)
 159                         return -EIO;
 160
 161                 memset(&output, 0, sizeof(output));
 162
 163                 size = *(u16 *) info->buffer.pointer;
 164                 if (size < 10) {
 165                         printk("ATPX buffer is too small: %zu\n", size);
 166                         kfree(info);
 167                         return -EINVAL;
 168                 }
 169                 size = min(sizeof(output), size);
 170
 171                 memcpy(&output, info->buffer.pointer, size);
 172
 173                 valid_bits = output.flags & output.valid_flags;
 174                 /* if separate mux flag is set, mux controls are required */
 175                 if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
 176                         atpx->functions.i2c_mux_cntl = true;
 177                         atpx->functions.disp_mux_cntl = true;
 178                 }
 179                 /* if any outputs are muxed, mux controls are required */
 180                 if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
 181                                   ATPX_TV_SIGNAL_MUXED |
 182                                   ATPX_DFP_SIGNAL_MUXED))
 183                         atpx->functions.disp_mux_cntl = true;
 184
 185                 kfree(info);
 186         }
 187         return 0;
 188 }
 189
 190 /**
 191  * radeon_atpx_verify_interface - verify ATPX
 192  *
 193  * @atpx: radeon atpx struct
 194  *
 195  * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
 196  * to initialize ATPX and determine what features are supported
 197  * (all asics).
 198  * returns 0 on success, error on failure.
 199  */
 200 static int radeon_atpx_verify_interface(struct radeon_atpx *atpx)
 201 {
 202         union acpi_object *info;
 203         struct atpx_verify_interface output;
 204         size_t size;
 205         int err = 0;
 206
 207         info = radeon_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
 208         if (!info)
 209                 return -EIO;
 210
 211         memset(&output, 0, sizeof(output));
 212
 213         size = *(u16 *) info->buffer.pointer;
 214         if (size < 8) {
 215                 printk("ATPX buffer is too small: %zu\n", size);
 216                 err = -EINVAL;
 217                 goto out;
 218         }
 219         size = min(sizeof(output), size);
 220
 221         memcpy(&output, info->buffer.pointer, size);
 222
 223         /* TODO: check version? */
 224         printk("ATPX version %u, functions 0x%08x\n",
 225                output.version, output.function_bits);
 226
 227         radeon_atpx_parse_functions(&atpx->functions, output.function_bits);
 228
 229 out:
 230         kfree(info);
 231         return err;
 232 }
 233
 234 /**
 235  * radeon_atpx_set_discrete_state - power up/down discrete GPU
 236  *
 237  * @atpx: atpx info struct
 238  * @state: discrete GPU state (0 = power down, 1 = power up)
 239  *
 240  * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
 241  * power down/up the discrete GPU (all asics).
 242  * Returns 0 on success, error on failure.
 243  */
 244 static int radeon_atpx_set_discrete_state(struct radeon_atpx *atpx, u8 state)
 245 {
 246         struct acpi_buffer params;
 247         union acpi_object *info;
 248         struct atpx_power_control input;
 249
 250         if (atpx->functions.power_cntl) {
 251                 input.size = 3;
 252                 input.dgpu_state = state;
 253                 params.length = input.size;
 254                 params.pointer = &input;
 255                 info = radeon_atpx_call(atpx->handle,
 256                                         ATPX_FUNCTION_POWER_CONTROL,
 257                                         &params);
 258                 if (!info)
 259                         return -EIO;
 260                 kfree(info);
 261         }
 262         return 0;
 263 }
 264
 265 /**
 266  * radeon_atpx_switch_disp_mux - switch display mux
 267  *
 268  * @atpx: atpx info struct
 269  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 270  *
 271  * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
 272  * switch the display mux between the discrete GPU and integrated GPU
 273  * (all asics).
 274  * Returns 0 on success, error on failure.
 275  */
 276 static int radeon_atpx_switch_disp_mux(struct radeon_atpx *atpx, u16 mux_id)
 277 {
 278         struct acpi_buffer params;
 279         union acpi_object *info;
 280         struct atpx_mux input;
 281
 282         if (atpx->functions.disp_mux_cntl) {
 283                 input.size = 4;
 284                 input.mux = mux_id;
 285                 params.length = input.size;
 286                 params.pointer = &input;
 287                 info = radeon_atpx_call(atpx->handle,
 288                                         ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
 289                                         &params);
 290                 if (!info)
 291                         return -EIO;
 292                 kfree(info);
 293         }
 294         return 0;
 295 }
 296
 297 /**
 298  * radeon_atpx_switch_i2c_mux - switch i2c/hpd mux
 299  *
 300  * @atpx: atpx info struct
 301  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 302  *
 303  * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
 304  * switch the i2c/hpd mux between the discrete GPU and integrated GPU
 305  * (all asics).
 306  * Returns 0 on success, error on failure.
 307  */
 308 static int radeon_atpx_switch_i2c_mux(struct radeon_atpx *atpx, u16 mux_id)
 309 {
 310         struct acpi_buffer params;
 311         union acpi_object *info;
 312         struct atpx_mux input;
 313
 314         if (atpx->functions.i2c_mux_cntl) {
 315                 input.size = 4;
 316                 input.mux = mux_id;
 317                 params.length = input.size;
 318                 params.pointer = &input;
 319                 info = radeon_atpx_call(atpx->handle,
 320                                         ATPX_FUNCTION_I2C_MUX_CONTROL,
 321                                         &params);
 322                 if (!info)
 323                         return -EIO;
 324                 kfree(info);
 325         }
 326         return 0;
 327 }
 328
 329 /**
 330  * radeon_atpx_switch_start - notify the sbios of a GPU switch
 331  *
 332  * @atpx: atpx info struct
 333  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 334  *
 335  * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
 336  * function to notify the sbios that a switch between the discrete GPU and
 337  * integrated GPU has begun (all asics).
 338  * Returns 0 on success, error on failure.
 339  */
 340 static int radeon_atpx_switch_start(struct radeon_atpx *atpx, u16 mux_id)
 341 {
 342         struct acpi_buffer params;
 343         union acpi_object *info;
 344         struct atpx_mux input;
 345
 346         if (atpx->functions.switch_start) {
 347                 input.size = 4;
 348                 input.mux = mux_id;
 349                 params.length = input.size;
 350                 params.pointer = &input;
 351                 info = radeon_atpx_call(atpx->handle,
 352                                         ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
 353                                         &params);
 354                 if (!info)
 355                         return -EIO;
 356                 kfree(info);
 357         }
 358         return 0;
 359 }
 360
 361 /**
 362  * radeon_atpx_switch_end - notify the sbios of a GPU switch
 363  *
 364  * @atpx: atpx info struct
 365  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 366  *
 367  * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
 368  * function to notify the sbios that a switch between the discrete GPU and
 369  * integrated GPU has ended (all asics).
 370  * Returns 0 on success, error on failure.
 371  */
 372 static int radeon_atpx_switch_end(struct radeon_atpx *atpx, u16 mux_id)
 373 {
 374         struct acpi_buffer params;
 375         union acpi_object *info;
 376         struct atpx_mux input;
 377
 378         if (atpx->functions.switch_end) {
 379                 input.size = 4;
 380                 input.mux = mux_id;
 381                 params.length = input.size;
 382                 params.pointer = &input;
 383                 info = radeon_atpx_call(atpx->handle,
 384                                         ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
 385                                         &params);
 386                 if (!info)
 387                         return -EIO;
 388                 kfree(info);
 389         }
 390         return 0;
 391 }
 392
 393 /**
 394  * radeon_atpx_switchto - switch to the requested GPU
 395  *
 396  * @id: GPU to switch to
 397  *
 398  * Execute the necessary ATPX functions to switch between the discrete GPU and
 399  * integrated GPU (all asics).
 400  * Returns 0 on success, error on failure.
 401  */
 402 static int radeon_atpx_switchto(enum vga_switcheroo_client_id id)
 403 {
 404         u16 gpu_id;
 405
 406         if (id == VGA_SWITCHEROO_IGD)
 407                 gpu_id = ATPX_INTEGRATED_GPU;
 408         else
 409                 gpu_id = ATPX_DISCRETE_GPU;
 410
 411         radeon_atpx_switch_start(&radeon_atpx_priv.atpx, gpu_id);
 412         radeon_atpx_switch_disp_mux(&radeon_atpx_priv.atpx, gpu_id);
 413         radeon_atpx_switch_i2c_mux(&radeon_atpx_priv.atpx, gpu_id);
 414         radeon_atpx_switch_end(&radeon_atpx_priv.atpx, gpu_id);
 415
 416         return 0;
 417 }
 418
 419 /**
 420  * radeon_atpx_power_state - power down/up the requested GPU
 421  *
 422  * @id: GPU to power down/up
 423  * @state: requested power state (0 = off, 1 = on)
 424  *
 425  * Execute the necessary ATPX function to power down/up the discrete GPU
 426  * (all asics).
 427  * Returns 0 on success, error on failure.
 428  */
 429 static int radeon_atpx_power_state(enum vga_switcheroo_client_id id,
 430                                    enum vga_switcheroo_state state)
 431 {
 432         /* on w500 ACPI can't change intel gpu state */
 433         if (id == VGA_SWITCHEROO_IGD)
 434                 return 0;
 435
 436         radeon_atpx_set_discrete_state(&radeon_atpx_priv.atpx, state);
 437         return 0;
 438 }
 439
 440 /**
 441  * radeon_atpx_pci_probe_handle - look up the ATPX handle
 442  *
 443  * @pdev: pci device
 444  *
 445  * Look up the ATPX handles (all asics).
 446  * Returns true if the handles are found, false if not.
 447  */
 448 static bool radeon_atpx_pci_probe_handle(struct pci_dev *pdev)
 449 {
 450         acpi_handle dhandle, atpx_handle;
 451         acpi_status status;
 452
 453         dhandle = ACPI_HANDLE(&pdev->dev);
 454         if (!dhandle)
 455                 return false;
 456
 457         status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
 458         if (ACPI_FAILURE(status))
 459                 return false;
 460
 461         radeon_atpx_priv.dhandle = dhandle;
 462         radeon_atpx_priv.atpx.handle = atpx_handle;
 463         return true;
 464 }
 465
 466 /**
 467  * radeon_atpx_init - verify the ATPX interface
 468  *
 469  * Verify the ATPX interface (all asics).
 470  * Returns 0 on success, error on failure.
 471  */
 472 static int radeon_atpx_init(void)
 473 {
 474         int r;
 475
 476         /* set up the ATPX handle */
 477         r = radeon_atpx_verify_interface(&radeon_atpx_priv.atpx);
 478         if (r)
 479                 return r;
 480
 481         /* validate the atpx setup */
 482         r = radeon_atpx_validate(&radeon_atpx_priv.atpx);
 483         if (r)
 484                 return r;
 485
 486         return 0;
 487 }
 488
 489 /**
 490  * radeon_atpx_get_client_id - get the client id
 491  *
 492  * @pdev: pci device
 493  *
 494  * look up whether we are the integrated or discrete GPU (all asics).
 495  * Returns the client id.
 496  */
 497 static int radeon_atpx_get_client_id(struct pci_dev *pdev)
 498 {
 499         if (radeon_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
 500                 return VGA_SWITCHEROO_IGD;
 501         else
 502                 return VGA_SWITCHEROO_DIS;
 503 }
 504
 505 static const struct vga_switcheroo_handler radeon_atpx_handler = {
 506         .switchto = radeon_atpx_switchto,
 507         .power_state = radeon_atpx_power_state,
 508         .init = radeon_atpx_init,
 509         .get_client_id = radeon_atpx_get_client_id,
 510 };
 511
 512 /**
 513  * radeon_atpx_detect - detect whether we have PX
 514  *
 515  * Check if we have a PX system (all asics).
 516  * Returns true if we have a PX system, false if not.
 517  */
 518 static bool radeon_atpx_detect(void)
 519 {
 520         char acpi_method_name[255] = { 0 };
 521         struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
 522         struct pci_dev *pdev = NULL;
 523         bool has_atpx = false;
 524         int vga_count = 0;
 525
 526         while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
 527                 vga_count++;
 528
 529                 has_atpx |= (radeon_atpx_pci_probe_handle(pdev) == true);
 530         }
 531
 532         /* some newer PX laptops mark the dGPU as a non-VGA display device */
 533         while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
 534                 vga_count++;
 535
 536                 has_atpx |= (radeon_atpx_pci_probe_handle(pdev) == true);
 537         }
 538
 539         if (has_atpx && vga_count == 2) {
 540                 acpi_get_name(radeon_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
 541                 printk(KERN_INFO "vga_switcheroo: detected switching method %s handle\n",
 542                        acpi_method_name);
 543                 radeon_atpx_priv.atpx_detected = true;
 544                 return true;
 545         }
 546         return false;
 547 }
 548
 549 /**
 550  * radeon_register_atpx_handler - register with vga_switcheroo
 551  *
 552  * Register the PX callbacks with vga_switcheroo (all asics).
 553  */
 554 void radeon_register_atpx_handler(void)
 555 {
 556         bool r;
 557         enum vga_switcheroo_handler_flags_t handler_flags = 0;
 558
 559         /* detect if we have any ATPX + 2 VGA in the system */
 560         r = radeon_atpx_detect();
 561         if (!r)
 562                 return;
 563
 564         vga_switcheroo_register_handler(&radeon_atpx_handler, handler_flags);
 565 }
 566
 567 /**
 568  * radeon_unregister_atpx_handler - unregister with vga_switcheroo
 569  *
 570  * Unregister the PX callbacks with vga_switcheroo (all asics).
 571  */
 572 void radeon_unregister_atpx_handler(void)
 573 {
 574         vga_switcheroo_unregister_handler();
 575 }