1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2010 Red Hat Inc.
4 * Author : Dave Airlie <airlied@redhat.com>
5 *
6 * ATPX support for both Intel/ATI
7 */
8 #include <linux/vga_switcheroo.h>
9 #include <linux/slab.h>
10 #include <linux/acpi.h>
11 #include <linux/pci.h>
12 #include <linux/delay.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 bool is_hybrid;
31 bool dgpu_req_power_for_displays;
32 };
33
34 static struct radeon_atpx_priv {
35 bool atpx_detected;
36 bool bridge_pm_usable;
37 /* handle for device - and atpx */
38 acpi_handle dhandle;
39 struct radeon_atpx atpx;
40 } radeon_atpx_priv;
41
42 struct atpx_verify_interface {
43 u16 size; /* structure size in bytes (includes size field) */
44 u16 version; /* version */
45 u32 function_bits; /* supported functions bit vector */
46 } __packed;
47
48 struct atpx_px_params {
49 u16 size; /* structure size in bytes (includes size field) */
50 u32 valid_flags; /* which flags are valid */
51 u32 flags; /* flags */
52 } __packed;
53
54 struct atpx_power_control {
55 u16 size;
56 u8 dgpu_state;
57 } __packed;
58
59 struct atpx_mux {
60 u16 size;
61 u16 mux;
62 } __packed;
63
radeon_has_atpx(void)64 bool radeon_has_atpx(void) {
65 return radeon_atpx_priv.atpx_detected;
66 }
67
radeon_has_atpx_dgpu_power_cntl(void)68 bool radeon_has_atpx_dgpu_power_cntl(void) {
69 return radeon_atpx_priv.atpx.functions.power_cntl;
70 }
71
radeon_is_atpx_hybrid(void)72 bool radeon_is_atpx_hybrid(void) {
73 return radeon_atpx_priv.atpx.is_hybrid;
74 }
75
radeon_atpx_dgpu_req_power_for_displays(void)76 bool radeon_atpx_dgpu_req_power_for_displays(void) {
77 return radeon_atpx_priv.atpx.dgpu_req_power_for_displays;
78 }
79
80 /**
81 * radeon_atpx_call - call an ATPX method
82 *
83 * @handle: acpi handle
84 * @function: the ATPX function to execute
85 * @params: ATPX function params
86 *
87 * Executes the requested ATPX function (all asics).
88 * Returns a pointer to the acpi output buffer.
89 */
radeon_atpx_call(acpi_handle handle,int function,struct acpi_buffer * params)90 static union acpi_object *radeon_atpx_call(acpi_handle handle, int function,
91 struct acpi_buffer *params)
92 {
93 acpi_status status;
94 union acpi_object atpx_arg_elements[2];
95 struct acpi_object_list atpx_arg;
96 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
97
98 atpx_arg.count = 2;
99 atpx_arg.pointer = &atpx_arg_elements[0];
100
101 atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
102 atpx_arg_elements[0].integer.value = function;
103
104 if (params) {
105 atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
106 atpx_arg_elements[1].buffer.length = params->length;
107 atpx_arg_elements[1].buffer.pointer = params->pointer;
108 } else {
109 /* We need a second fake parameter */
110 atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
111 atpx_arg_elements[1].integer.value = 0;
112 }
113
114 status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);
115
116 /* Fail only if calling the method fails and ATPX is supported */
117 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
118 pr_err("failed to evaluate ATPX got %s\n",
119 acpi_format_exception(status));
120 kfree(buffer.pointer);
121 return NULL;
122 }
123
124 return buffer.pointer;
125 }
126
127 /**
128 * radeon_atpx_parse_functions - parse supported functions
129 *
130 * @f: supported functions struct
131 * @mask: supported functions mask from ATPX
132 *
133 * Use the supported functions mask from ATPX function
134 * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
135 * are supported (all asics).
136 */
radeon_atpx_parse_functions(struct radeon_atpx_functions * f,u32 mask)137 static void radeon_atpx_parse_functions(struct radeon_atpx_functions *f, u32 mask)
138 {
139 f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
140 f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
141 f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
142 f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
143 f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
144 f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
145 f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
146 f->disp_detetion_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
147 }
148
149 /**
150 * radeon_atpx_validate() - validate ATPX functions
151 *
152 * @atpx: radeon atpx struct
153 *
154 * Validate that required functions are enabled (all asics).
155 * returns 0 on success, error on failure.
156 */
radeon_atpx_validate(struct radeon_atpx * atpx)157 static int radeon_atpx_validate(struct radeon_atpx *atpx)
158 {
159 u32 valid_bits = 0;
160
161 if (atpx->functions.px_params) {
162 union acpi_object *info;
163 struct atpx_px_params output;
164 size_t size;
165
166 info = radeon_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
167 if (!info)
168 return -EIO;
169
170 memset(&output, 0, sizeof(output));
171
172 size = *(u16 *) info->buffer.pointer;
173 if (size < 10) {
174 pr_err("ATPX buffer is too small: %zu\n", size);
175 kfree(info);
176 return -EINVAL;
177 }
178 size = min(sizeof(output), size);
179
180 memcpy(&output, info->buffer.pointer, size);
181
182 valid_bits = output.flags & output.valid_flags;
183
184 kfree(info);
185 }
186
187 /* if separate mux flag is set, mux controls are required */
188 if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
189 atpx->functions.i2c_mux_cntl = true;
190 atpx->functions.disp_mux_cntl = true;
191 }
192 /* if any outputs are muxed, mux controls are required */
193 if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
194 ATPX_TV_SIGNAL_MUXED |
195 ATPX_DFP_SIGNAL_MUXED))
196 atpx->functions.disp_mux_cntl = true;
197
198 /* some bioses set these bits rather than flagging power_cntl as supported */
199 if (valid_bits & (ATPX_DYNAMIC_PX_SUPPORTED |
200 ATPX_DYNAMIC_DGPU_POWER_OFF_SUPPORTED))
201 atpx->functions.power_cntl = true;
202
203 atpx->is_hybrid = false;
204 if (valid_bits & ATPX_MS_HYBRID_GFX_SUPPORTED) {
205 pr_info("ATPX Hybrid Graphics\n");
206 /*
207 * Disable legacy PM methods only when pcie port PM is usable,
208 * otherwise the device might fail to power off or power on.
209 */
210 atpx->functions.power_cntl = !radeon_atpx_priv.bridge_pm_usable;
211 atpx->is_hybrid = true;
212 }
213
214 return 0;
215 }
216
217 /**
218 * radeon_atpx_verify_interface - verify ATPX
219 *
220 * @atpx: radeon atpx struct
221 *
222 * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
223 * to initialize ATPX and determine what features are supported
224 * (all asics).
225 * returns 0 on success, error on failure.
226 */
radeon_atpx_verify_interface(struct radeon_atpx * atpx)227 static int radeon_atpx_verify_interface(struct radeon_atpx *atpx)
228 {
229 union acpi_object *info;
230 struct atpx_verify_interface output;
231 size_t size;
232 int err = 0;
233
234 info = radeon_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
235 if (!info)
236 return -EIO;
237
238 memset(&output, 0, sizeof(output));
239
240 size = *(u16 *) info->buffer.pointer;
241 if (size < 8) {
242 pr_err("ATPX buffer is too small: %zu\n", size);
243 err = -EINVAL;
244 goto out;
245 }
246 size = min(sizeof(output), size);
247
248 memcpy(&output, info->buffer.pointer, size);
249
250 /* TODO: check version? */
251 pr_info("ATPX version %u, functions 0x%08x\n",
252 output.version, output.function_bits);
253
254 radeon_atpx_parse_functions(&atpx->functions, output.function_bits);
255
256 out:
257 kfree(info);
258 return err;
259 }
260
261 /**
262 * radeon_atpx_set_discrete_state - power up/down discrete GPU
263 *
264 * @atpx: atpx info struct
265 * @state: discrete GPU state (0 = power down, 1 = power up)
266 *
267 * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
268 * power down/up the discrete GPU (all asics).
269 * Returns 0 on success, error on failure.
270 */
radeon_atpx_set_discrete_state(struct radeon_atpx * atpx,u8 state)271 static int radeon_atpx_set_discrete_state(struct radeon_atpx *atpx, u8 state)
272 {
273 struct acpi_buffer params;
274 union acpi_object *info;
275 struct atpx_power_control input;
276
277 if (atpx->functions.power_cntl) {
278 input.size = 3;
279 input.dgpu_state = state;
280 params.length = input.size;
281 params.pointer = &input;
282 info = radeon_atpx_call(atpx->handle,
283 ATPX_FUNCTION_POWER_CONTROL,
284 ¶ms);
285 if (!info)
286 return -EIO;
287 kfree(info);
288
289 /* 200ms delay is required after off */
290 if (state == 0)
291 msleep(200);
292 }
293 return 0;
294 }
295
296 /**
297 * radeon_atpx_switch_disp_mux - switch display mux
298 *
299 * @atpx: atpx info struct
300 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
301 *
302 * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
303 * switch the display mux between the discrete GPU and integrated GPU
304 * (all asics).
305 * Returns 0 on success, error on failure.
306 */
radeon_atpx_switch_disp_mux(struct radeon_atpx * atpx,u16 mux_id)307 static int radeon_atpx_switch_disp_mux(struct radeon_atpx *atpx, u16 mux_id)
308 {
309 struct acpi_buffer params;
310 union acpi_object *info;
311 struct atpx_mux input;
312
313 if (atpx->functions.disp_mux_cntl) {
314 input.size = 4;
315 input.mux = mux_id;
316 params.length = input.size;
317 params.pointer = &input;
318 info = radeon_atpx_call(atpx->handle,
319 ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
320 ¶ms);
321 if (!info)
322 return -EIO;
323 kfree(info);
324 }
325 return 0;
326 }
327
328 /**
329 * radeon_atpx_switch_i2c_mux - switch i2c/hpd mux
330 *
331 * @atpx: atpx info struct
332 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
333 *
334 * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
335 * switch the i2c/hpd mux between the discrete GPU and integrated GPU
336 * (all asics).
337 * Returns 0 on success, error on failure.
338 */
radeon_atpx_switch_i2c_mux(struct radeon_atpx * atpx,u16 mux_id)339 static int radeon_atpx_switch_i2c_mux(struct radeon_atpx *atpx, u16 mux_id)
340 {
341 struct acpi_buffer params;
342 union acpi_object *info;
343 struct atpx_mux input;
344
345 if (atpx->functions.i2c_mux_cntl) {
346 input.size = 4;
347 input.mux = mux_id;
348 params.length = input.size;
349 params.pointer = &input;
350 info = radeon_atpx_call(atpx->handle,
351 ATPX_FUNCTION_I2C_MUX_CONTROL,
352 ¶ms);
353 if (!info)
354 return -EIO;
355 kfree(info);
356 }
357 return 0;
358 }
359
360 /**
361 * radeon_atpx_switch_start - notify the sbios of a GPU switch
362 *
363 * @atpx: atpx info struct
364 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
365 *
366 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
367 * function to notify the sbios that a switch between the discrete GPU and
368 * integrated GPU has begun (all asics).
369 * Returns 0 on success, error on failure.
370 */
radeon_atpx_switch_start(struct radeon_atpx * atpx,u16 mux_id)371 static int radeon_atpx_switch_start(struct radeon_atpx *atpx, u16 mux_id)
372 {
373 struct acpi_buffer params;
374 union acpi_object *info;
375 struct atpx_mux input;
376
377 if (atpx->functions.switch_start) {
378 input.size = 4;
379 input.mux = mux_id;
380 params.length = input.size;
381 params.pointer = &input;
382 info = radeon_atpx_call(atpx->handle,
383 ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
384 ¶ms);
385 if (!info)
386 return -EIO;
387 kfree(info);
388 }
389 return 0;
390 }
391
392 /**
393 * radeon_atpx_switch_end - notify the sbios of a GPU switch
394 *
395 * @atpx: atpx info struct
396 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
397 *
398 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
399 * function to notify the sbios that a switch between the discrete GPU and
400 * integrated GPU has ended (all asics).
401 * Returns 0 on success, error on failure.
402 */
radeon_atpx_switch_end(struct radeon_atpx * atpx,u16 mux_id)403 static int radeon_atpx_switch_end(struct radeon_atpx *atpx, u16 mux_id)
404 {
405 struct acpi_buffer params;
406 union acpi_object *info;
407 struct atpx_mux input;
408
409 if (atpx->functions.switch_end) {
410 input.size = 4;
411 input.mux = mux_id;
412 params.length = input.size;
413 params.pointer = &input;
414 info = radeon_atpx_call(atpx->handle,
415 ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
416 ¶ms);
417 if (!info)
418 return -EIO;
419 kfree(info);
420 }
421 return 0;
422 }
423
424 /**
425 * radeon_atpx_switchto - switch to the requested GPU
426 *
427 * @id: GPU to switch to
428 *
429 * Execute the necessary ATPX functions to switch between the discrete GPU and
430 * integrated GPU (all asics).
431 * Returns 0 on success, error on failure.
432 */
radeon_atpx_switchto(enum vga_switcheroo_client_id id)433 static int radeon_atpx_switchto(enum vga_switcheroo_client_id id)
434 {
435 u16 gpu_id;
436
437 if (id == VGA_SWITCHEROO_IGD)
438 gpu_id = ATPX_INTEGRATED_GPU;
439 else
440 gpu_id = ATPX_DISCRETE_GPU;
441
442 radeon_atpx_switch_start(&radeon_atpx_priv.atpx, gpu_id);
443 radeon_atpx_switch_disp_mux(&radeon_atpx_priv.atpx, gpu_id);
444 radeon_atpx_switch_i2c_mux(&radeon_atpx_priv.atpx, gpu_id);
445 radeon_atpx_switch_end(&radeon_atpx_priv.atpx, gpu_id);
446
447 return 0;
448 }
449
450 /**
451 * radeon_atpx_power_state - power down/up the requested GPU
452 *
453 * @id: GPU to power down/up
454 * @state: requested power state (0 = off, 1 = on)
455 *
456 * Execute the necessary ATPX function to power down/up the discrete GPU
457 * (all asics).
458 * Returns 0 on success, error on failure.
459 */
radeon_atpx_power_state(enum vga_switcheroo_client_id id,enum vga_switcheroo_state state)460 static int radeon_atpx_power_state(enum vga_switcheroo_client_id id,
461 enum vga_switcheroo_state state)
462 {
463 /* on w500 ACPI can't change intel gpu state */
464 if (id == VGA_SWITCHEROO_IGD)
465 return 0;
466
467 radeon_atpx_set_discrete_state(&radeon_atpx_priv.atpx, state);
468 return 0;
469 }
470
471 /**
472 * radeon_atpx_pci_probe_handle - look up the ATPX handle
473 *
474 * @pdev: pci device
475 *
476 * Look up the ATPX handles (all asics).
477 * Returns true if the handles are found, false if not.
478 */
radeon_atpx_pci_probe_handle(struct pci_dev * pdev)479 static bool radeon_atpx_pci_probe_handle(struct pci_dev *pdev)
480 {
481 acpi_handle dhandle, atpx_handle;
482 acpi_status status;
483
484 dhandle = ACPI_HANDLE(&pdev->dev);
485 if (!dhandle)
486 return false;
487
488 status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
489 if (ACPI_FAILURE(status))
490 return false;
491
492 radeon_atpx_priv.dhandle = dhandle;
493 radeon_atpx_priv.atpx.handle = atpx_handle;
494 return true;
495 }
496
497 /**
498 * radeon_atpx_init - verify the ATPX interface
499 *
500 * Verify the ATPX interface (all asics).
501 * Returns 0 on success, error on failure.
502 */
radeon_atpx_init(void)503 static int radeon_atpx_init(void)
504 {
505 int r;
506
507 /* set up the ATPX handle */
508 r = radeon_atpx_verify_interface(&radeon_atpx_priv.atpx);
509 if (r)
510 return r;
511
512 /* validate the atpx setup */
513 r = radeon_atpx_validate(&radeon_atpx_priv.atpx);
514 if (r)
515 return r;
516
517 return 0;
518 }
519
520 /**
521 * radeon_atpx_get_client_id - get the client id
522 *
523 * @pdev: pci device
524 *
525 * look up whether we are the integrated or discrete GPU (all asics).
526 * Returns the client id.
527 */
radeon_atpx_get_client_id(struct pci_dev * pdev)528 static enum vga_switcheroo_client_id radeon_atpx_get_client_id(struct pci_dev *pdev)
529 {
530 if (radeon_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
531 return VGA_SWITCHEROO_IGD;
532 else
533 return VGA_SWITCHEROO_DIS;
534 }
535
536 static const struct vga_switcheroo_handler radeon_atpx_handler = {
537 .switchto = radeon_atpx_switchto,
538 .power_state = radeon_atpx_power_state,
539 .get_client_id = radeon_atpx_get_client_id,
540 };
541
542 /**
543 * radeon_atpx_detect - detect whether we have PX
544 *
545 * Check if we have a PX system (all asics).
546 * Returns true if we have a PX system, false if not.
547 */
radeon_atpx_detect(void)548 static bool radeon_atpx_detect(void)
549 {
550 char acpi_method_name[255] = { 0 };
551 struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
552 struct pci_dev *pdev = NULL;
553 bool has_atpx = false;
554 int vga_count = 0;
555 bool d3_supported = false;
556 struct pci_dev *parent_pdev;
557
558 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
559 vga_count++;
560
561 has_atpx |= (radeon_atpx_pci_probe_handle(pdev) == true);
562
563 parent_pdev = pci_upstream_bridge(pdev);
564 d3_supported |= parent_pdev && parent_pdev->bridge_d3;
565 }
566
567 /* some newer PX laptops mark the dGPU as a non-VGA display device */
568 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
569 vga_count++;
570
571 has_atpx |= (radeon_atpx_pci_probe_handle(pdev) == true);
572
573 parent_pdev = pci_upstream_bridge(pdev);
574 d3_supported |= parent_pdev && parent_pdev->bridge_d3;
575 }
576
577 if (has_atpx && vga_count == 2) {
578 acpi_get_name(radeon_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
579 pr_info("vga_switcheroo: detected switching method %s handle\n",
580 acpi_method_name);
581 radeon_atpx_priv.atpx_detected = true;
582 radeon_atpx_priv.bridge_pm_usable = d3_supported;
583 radeon_atpx_init();
584 return true;
585 }
586 return false;
587 }
588
589 /**
590 * radeon_register_atpx_handler - register with vga_switcheroo
591 *
592 * Register the PX callbacks with vga_switcheroo (all asics).
593 */
radeon_register_atpx_handler(void)594 void radeon_register_atpx_handler(void)
595 {
596 bool r;
597 enum vga_switcheroo_handler_flags_t handler_flags = 0;
598
599 /* detect if we have any ATPX + 2 VGA in the system */
600 r = radeon_atpx_detect();
601 if (!r)
602 return;
603
604 vga_switcheroo_register_handler(&radeon_atpx_handler, handler_flags);
605 }
606
607 /**
608 * radeon_unregister_atpx_handler - unregister with vga_switcheroo
609 *
610 * Unregister the PX callbacks with vga_switcheroo (all asics).
611 */
radeon_unregister_atpx_handler(void)612 void radeon_unregister_atpx_handler(void)
613 {
614 vga_switcheroo_unregister_handler();
615 }
616