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