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 <acpi/acpi.h>
  12 #include <acpi/acpi_bus.h>
  13 #include <linux/pci.h>
  14
  15 #include "radeon_acpi.h"
  16
  17 struct radeon_atpx_functions {
  18         bool px_params;
  19         bool power_cntl;
  20         bool disp_mux_cntl;
  21         bool i2c_mux_cntl;
  22         bool switch_start;
  23         bool switch_end;
  24         bool disp_connectors_mapping;
  25         bool disp_detetion_ports;
  26 };
  27
  28 struct radeon_atpx {
  29         acpi_handle handle;
  30         struct radeon_atpx_functions functions;
  31 };
  32
  33 static struct radeon_atpx_priv {
  34         bool atpx_detected;
  35         /* handle for device - and atpx */
  36         acpi_handle dhandle;
  37         struct radeon_atpx atpx;
  38 } radeon_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 /**
  63  * radeon_atpx_call - call an ATPX method
  64  *
  65  * @handle: acpi handle
  66  * @function: the ATPX function to execute
  67  * @params: ATPX function params
  68  *
  69  * Executes the requested ATPX function (all asics).
  70  * Returns a pointer to the acpi output buffer.
  71  */
  72 static union acpi_object *radeon_atpx_call(acpi_handle handle, int function,
  73                                            struct acpi_buffer *params)
  74 {
  75         acpi_status status;
  76         union acpi_object atpx_arg_elements[2];
  77         struct acpi_object_list atpx_arg;
  78         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  79
  80         atpx_arg.count = 2;
  81         atpx_arg.pointer = &atpx_arg_elements[0];
  82
  83         atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
  84         atpx_arg_elements[0].integer.value = function;
  85
  86         if (params) {
  87                 atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
  88                 atpx_arg_elements[1].buffer.length = params->length;
  89                 atpx_arg_elements[1].buffer.pointer = params->pointer;
  90         } else {
  91                 /* We need a second fake parameter */
  92                 atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
  93                 atpx_arg_elements[1].integer.value = 0;
  94         }
  95
  96         status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);
  97
  98         /* Fail only if calling the method fails and ATPX is supported */
  99         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 100                 printk("failed to evaluate ATPX got %s\n",
 101                        acpi_format_exception(status));
 102                 kfree(buffer.pointer);
 103                 return NULL;
 104         }
 105
 106         return buffer.pointer;
 107 }
 108
 109 /**
 110  * radeon_atpx_parse_functions - parse supported functions
 111  *
 112  * @f: supported functions struct
 113  * @mask: supported functions mask from ATPX
 114  *
 115  * Use the supported functions mask from ATPX function
 116  * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
 117  * are supported (all asics).
 118  */
 119 static void radeon_atpx_parse_functions(struct radeon_atpx_functions *f, u32 mask)
 120 {
 121         f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
 122         f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
 123         f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
 124         f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
 125         f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
 126         f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
 127         f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
 128         f->disp_detetion_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
 129 }
 130
 131 /**
 132  * radeon_atpx_validate_functions - validate ATPX functions
 133  *
 134  * @atpx: radeon atpx struct
 135  *
 136  * Validate that required functions are enabled (all asics).
 137  * returns 0 on success, error on failure.
 138  */
 139 static int radeon_atpx_validate(struct radeon_atpx *atpx)
 140 {
 141         /* make sure required functions are enabled */
 142         /* dGPU power control is required */
 143         atpx->functions.power_cntl = true;
 144
 145         if (atpx->functions.px_params) {
 146                 union acpi_object *info;
 147                 struct atpx_px_params output;
 148                 size_t size;
 149                 u32 valid_bits;
 150
 151                 info = radeon_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
 152                 if (!info)
 153                         return -EIO;
 154
 155                 memset(&output, 0, sizeof(output));
 156
 157                 size = *(u16 *) info->buffer.pointer;
 158                 if (size < 10) {
 159                         printk("ATPX buffer is too small: %zu\n", size);
 160                         kfree(info);
 161                         return -EINVAL;
 162                 }
 163                 size = min(sizeof(output), size);
 164
 165                 memcpy(&output, info->buffer.pointer, size);
 166
 167                 valid_bits = output.flags & output.valid_flags;
 168                 /* if separate mux flag is set, mux controls are required */
 169                 if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
 170                         atpx->functions.i2c_mux_cntl = true;
 171                         atpx->functions.disp_mux_cntl = true;
 172                 }
 173                 /* if any outputs are muxed, mux controls are required */
 174                 if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
 175                                   ATPX_TV_SIGNAL_MUXED |
 176                                   ATPX_DFP_SIGNAL_MUXED))
 177                         atpx->functions.disp_mux_cntl = true;
 178
 179                 kfree(info);
 180         }
 181         return 0;
 182 }
 183
 184 /**
 185  * radeon_atpx_verify_interface - verify ATPX
 186  *
 187  * @atpx: radeon atpx struct
 188  *
 189  * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
 190  * to initialize ATPX and determine what features are supported
 191  * (all asics).
 192  * returns 0 on success, error on failure.
 193  */
 194 static int radeon_atpx_verify_interface(struct radeon_atpx *atpx)
 195 {
 196         union acpi_object *info;
 197         struct atpx_verify_interface output;
 198         size_t size;
 199         int err = 0;
 200
 201         info = radeon_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
 202         if (!info)
 203                 return -EIO;
 204
 205         memset(&output, 0, sizeof(output));
 206
 207         size = *(u16 *) info->buffer.pointer;
 208         if (size < 8) {
 209                 printk("ATPX buffer is too small: %zu\n", size);
 210                 err = -EINVAL;
 211                 goto out;
 212         }
 213         size = min(sizeof(output), size);
 214
 215         memcpy(&output, info->buffer.pointer, size);
 216
 217         /* TODO: check version? */
 218         printk("ATPX version %u, functions 0x%08x\n",
 219                output.version, output.function_bits);
 220
 221         radeon_atpx_parse_functions(&atpx->functions, output.function_bits);
 222
 223 out:
 224         kfree(info);
 225         return err;
 226 }
 227
 228 /**
 229  * radeon_atpx_set_discrete_state - power up/down discrete GPU
 230  *
 231  * @atpx: atpx info struct
 232  * @state: discrete GPU state (0 = power down, 1 = power up)
 233  *
 234  * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
 235  * power down/up the discrete GPU (all asics).
 236  * Returns 0 on success, error on failure.
 237  */
 238 static int radeon_atpx_set_discrete_state(struct radeon_atpx *atpx, u8 state)
 239 {
 240         struct acpi_buffer params;
 241         union acpi_object *info;
 242         struct atpx_power_control input;
 243
 244         if (atpx->functions.power_cntl) {
 245                 input.size = 3;
 246                 input.dgpu_state = state;
 247                 params.length = input.size;
 248                 params.pointer = &input;
 249                 info = radeon_atpx_call(atpx->handle,
 250                                         ATPX_FUNCTION_POWER_CONTROL,
 251                                         &params);
 252                 if (!info)
 253                         return -EIO;
 254                 kfree(info);
 255         }
 256         return 0;
 257 }
 258
 259 /**
 260  * radeon_atpx_switch_disp_mux - switch display mux
 261  *
 262  * @atpx: atpx info struct
 263  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 264  *
 265  * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
 266  * switch the display mux between the discrete GPU and integrated GPU
 267  * (all asics).
 268  * Returns 0 on success, error on failure.
 269  */
 270 static int radeon_atpx_switch_disp_mux(struct radeon_atpx *atpx, u16 mux_id)
 271 {
 272         struct acpi_buffer params;
 273         union acpi_object *info;
 274         struct atpx_mux input;
 275
 276         if (atpx->functions.disp_mux_cntl) {
 277                 input.size = 4;
 278                 input.mux = mux_id;
 279                 params.length = input.size;
 280                 params.pointer = &input;
 281                 info = radeon_atpx_call(atpx->handle,
 282                                         ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
 283                                         &params);
 284                 if (!info)
 285                         return -EIO;
 286                 kfree(info);
 287         }
 288         return 0;
 289 }
 290
 291 /**
 292  * radeon_atpx_switch_i2c_mux - switch i2c/hpd mux
 293  *
 294  * @atpx: atpx info struct
 295  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 296  *
 297  * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
 298  * switch the i2c/hpd mux between the discrete GPU and integrated GPU
 299  * (all asics).
 300  * Returns 0 on success, error on failure.
 301  */
 302 static int radeon_atpx_switch_i2c_mux(struct radeon_atpx *atpx, u16 mux_id)
 303 {
 304         struct acpi_buffer params;
 305         union acpi_object *info;
 306         struct atpx_mux input;
 307
 308         if (atpx->functions.i2c_mux_cntl) {
 309                 input.size = 4;
 310                 input.mux = mux_id;
 311                 params.length = input.size;
 312                 params.pointer = &input;
 313                 info = radeon_atpx_call(atpx->handle,
 314                                         ATPX_FUNCTION_I2C_MUX_CONTROL,
 315                                         &params);
 316                 if (!info)
 317                         return -EIO;
 318                 kfree(info);
 319         }
 320         return 0;
 321 }
 322
 323 /**
 324  * radeon_atpx_switch_start - notify the sbios of a GPU switch
 325  *
 326  * @atpx: atpx info struct
 327  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 328  *
 329  * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
 330  * function to notify the sbios that a switch between the discrete GPU and
 331  * integrated GPU has begun (all asics).
 332  * Returns 0 on success, error on failure.
 333  */
 334 static int radeon_atpx_switch_start(struct radeon_atpx *atpx, u16 mux_id)
 335 {
 336         struct acpi_buffer params;
 337         union acpi_object *info;
 338         struct atpx_mux input;
 339
 340         if (atpx->functions.switch_start) {
 341                 input.size = 4;
 342                 input.mux = mux_id;
 343                 params.length = input.size;
 344                 params.pointer = &input;
 345                 info = radeon_atpx_call(atpx->handle,
 346                                         ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
 347                                         &params);
 348                 if (!info)
 349                         return -EIO;
 350                 kfree(info);
 351         }
 352         return 0;
 353 }
 354
 355 /**
 356  * radeon_atpx_switch_end - notify the sbios of a GPU switch
 357  *
 358  * @atpx: atpx info struct
 359  * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
 360  *
 361  * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
 362  * function to notify the sbios that a switch between the discrete GPU and
 363  * integrated GPU has ended (all asics).
 364  * Returns 0 on success, error on failure.
 365  */
 366 static int radeon_atpx_switch_end(struct radeon_atpx *atpx, u16 mux_id)
 367 {
 368         struct acpi_buffer params;
 369         union acpi_object *info;
 370         struct atpx_mux input;
 371
 372         if (atpx->functions.switch_end) {
 373                 input.size = 4;
 374                 input.mux = mux_id;
 375                 params.length = input.size;
 376                 params.pointer = &input;
 377                 info = radeon_atpx_call(atpx->handle,
 378                                         ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
 379                                         &params);
 380                 if (!info)
 381                         return -EIO;
 382                 kfree(info);
 383         }
 384         return 0;
 385 }
 386
 387 /**
 388  * radeon_atpx_switchto - switch to the requested GPU
 389  *
 390  * @id: GPU to switch to
 391  *
 392  * Execute the necessary ATPX functions to switch between the discrete GPU and
 393  * integrated GPU (all asics).
 394  * Returns 0 on success, error on failure.
 395  */
 396 static int radeon_atpx_switchto(enum vga_switcheroo_client_id id)
 397 {
 398         u16 gpu_id;
 399
 400         if (id == VGA_SWITCHEROO_IGD)
 401                 gpu_id = ATPX_INTEGRATED_GPU;
 402         else
 403                 gpu_id = ATPX_DISCRETE_GPU;
 404
 405         radeon_atpx_switch_start(&radeon_atpx_priv.atpx, gpu_id);
 406         radeon_atpx_switch_disp_mux(&radeon_atpx_priv.atpx, gpu_id);
 407         radeon_atpx_switch_i2c_mux(&radeon_atpx_priv.atpx, gpu_id);
 408         radeon_atpx_switch_end(&radeon_atpx_priv.atpx, gpu_id);
 409
 410         return 0;
 411 }
 412
 413 /**
 414  * radeon_atpx_power_state - power down/up the requested GPU
 415  *
 416  * @id: GPU to power down/up
 417  * @state: requested power state (0 = off, 1 = on)
 418  *
 419  * Execute the necessary ATPX function to power down/up the discrete GPU
 420  * (all asics).
 421  * Returns 0 on success, error on failure.
 422  */
 423 static int radeon_atpx_power_state(enum vga_switcheroo_client_id id,
 424                                    enum vga_switcheroo_state state)
 425 {
 426         /* on w500 ACPI can't change intel gpu state */
 427         if (id == VGA_SWITCHEROO_IGD)
 428                 return 0;
 429
 430         radeon_atpx_set_discrete_state(&radeon_atpx_priv.atpx, state);
 431         return 0;
 432 }
 433
 434 /**
 435  * radeon_atpx_pci_probe_handle - look up the ATPX handle
 436  *
 437  * @pdev: pci device
 438  *
 439  * Look up the ATPX handles (all asics).
 440  * Returns true if the handles are found, false if not.
 441  */
 442 static bool radeon_atpx_pci_probe_handle(struct pci_dev *pdev)
 443 {
 444         acpi_handle dhandle, atpx_handle;
 445         acpi_status status;
 446
 447         dhandle = DEVICE_ACPI_HANDLE(&pdev->dev);
 448         if (!dhandle)
 449                 return false;
 450
 451         status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
 452         if (ACPI_FAILURE(status))
 453                 return false;
 454
 455         radeon_atpx_priv.dhandle = dhandle;
 456         radeon_atpx_priv.atpx.handle = atpx_handle;
 457         return true;
 458 }
 459
 460 /**
 461  * radeon_atpx_init - verify the ATPX interface
 462  *
 463  * Verify the ATPX interface (all asics).
 464  * Returns 0 on success, error on failure.
 465  */
 466 static int radeon_atpx_init(void)
 467 {
 468         int r;
 469
 470         /* set up the ATPX handle */
 471         r = radeon_atpx_verify_interface(&radeon_atpx_priv.atpx);
 472         if (r)
 473                 return r;
 474
 475         /* validate the atpx setup */
 476         r = radeon_atpx_validate(&radeon_atpx_priv.atpx);
 477         if (r)
 478                 return r;
 479
 480         return 0;
 481 }
 482
 483 /**
 484  * radeon_atpx_get_client_id - get the client id
 485  *
 486  * @pdev: pci device
 487  *
 488  * look up whether we are the integrated or discrete GPU (all asics).
 489  * Returns the client id.
 490  */
 491 static int radeon_atpx_get_client_id(struct pci_dev *pdev)
 492 {
 493         if (radeon_atpx_priv.dhandle == DEVICE_ACPI_HANDLE(&pdev->dev))
 494                 return VGA_SWITCHEROO_IGD;
 495         else
 496                 return VGA_SWITCHEROO_DIS;
 497 }
 498
 499 static struct vga_switcheroo_handler radeon_atpx_handler = {
 500         .switchto = radeon_atpx_switchto,
 501         .power_state = radeon_atpx_power_state,
 502         .init = radeon_atpx_init,
 503         .get_client_id = radeon_atpx_get_client_id,
 504 };
 505
 506 /**
 507  * radeon_atpx_detect - detect whether we have PX
 508  *
 509  * Check if we have a PX system (all asics).
 510  * Returns true if we have a PX system, false if not.
 511  */
 512 static bool radeon_atpx_detect(void)
 513 {
 514         char acpi_method_name[255] = { 0 };
 515         struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
 516         struct pci_dev *pdev = NULL;
 517         bool has_atpx = false;
 518         int vga_count = 0;
 519
 520         while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
 521                 vga_count++;
 522
 523                 has_atpx |= (radeon_atpx_pci_probe_handle(pdev) == true);
 524         }
 525
 526         if (has_atpx && vga_count == 2) {
 527                 acpi_get_name(radeon_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
 528                 printk(KERN_INFO "VGA switcheroo: detected switching method %s handle\n",
 529                        acpi_method_name);
 530                 radeon_atpx_priv.atpx_detected = true;
 531                 return true;
 532         }
 533         return false;
 534 }
 535
 536 /**
 537  * radeon_register_atpx_handler - register with vga_switcheroo
 538  *
 539  * Register the PX callbacks with vga_switcheroo (all asics).
 540  */
 541 void radeon_register_atpx_handler(void)
 542 {
 543         bool r;
 544
 545         /* detect if we have any ATPX + 2 VGA in the system */
 546         r = radeon_atpx_detect();
 547         if (!r)
 548                 return;
 549
 550         vga_switcheroo_register_handler(&radeon_atpx_handler);
 551 }
 552
 553 /**
 554  * radeon_unregister_atpx_handler - unregister with vga_switcheroo
 555  *
 556  * Unregister the PX callbacks with vga_switcheroo (all asics).
 557  */
 558 void radeon_unregister_atpx_handler(void)
 559 {
 560         vga_switcheroo_unregister_handler();
 561 }