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
16struct 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
27struct 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
34static 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
42struct 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
48struct 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
54struct atpx_power_control {
55 u16 size;
56 u8 dgpu_state;
57} __packed;
58
59struct atpx_mux {
60 u16 size;
61 u16 mux;
62} __packed;
63
64bool radeon_has_atpx(void)
65{
66 return radeon_atpx_priv.atpx_detected;
67}
68
69bool radeon_has_atpx_dgpu_power_cntl(void)
70{
71 return radeon_atpx_priv.atpx.functions.power_cntl;
72}
73
74bool radeon_is_atpx_hybrid(void)
75{
76 return radeon_atpx_priv.atpx.is_hybrid;
77}
78
79bool radeon_atpx_dgpu_req_power_for_displays(void)
80{
81 return radeon_atpx_priv.atpx.dgpu_req_power_for_displays;
82}
83
84/**
85 * radeon_atpx_call - call an ATPX method
86 *
87 * @handle: acpi handle
88 * @function: the ATPX function to execute
89 * @params: ATPX function params
90 *
91 * Executes the requested ATPX function (all asics).
92 * Returns a pointer to the acpi output buffer.
93 */
94static union acpi_object *radeon_atpx_call(acpi_handle handle, int function,
95 struct acpi_buffer *params)
96{
97 acpi_status status;
98 union acpi_object atpx_arg_elements[2];
99 struct acpi_object_list atpx_arg;
100 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
101
102 atpx_arg.count = 2;
103 atpx_arg.pointer = &atpx_arg_elements[0];
104
105 atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
106 atpx_arg_elements[0].integer.value = function;
107
108 if (params) {
109 atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
110 atpx_arg_elements[1].buffer.length = params->length;
111 atpx_arg_elements[1].buffer.pointer = params->pointer;
112 } else {
113 /* We need a second fake parameter */
114 atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
115 atpx_arg_elements[1].integer.value = 0;
116 }
117
118 status = acpi_evaluate_object(object: handle, NULL, parameter_objects: &atpx_arg, return_object_buffer: &buffer);
119
120 /* Fail only if calling the method fails and ATPX is supported */
121 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
122 pr_err("failed to evaluate ATPX got %s\n",
123 acpi_format_exception(status));
124 kfree(objp: buffer.pointer);
125 return NULL;
126 }
127
128 return buffer.pointer;
129}
130
131/**
132 * radeon_atpx_parse_functions - parse supported functions
133 *
134 * @f: supported functions struct
135 * @mask: supported functions mask from ATPX
136 *
137 * Use the supported functions mask from ATPX function
138 * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
139 * are supported (all asics).
140 */
141static void radeon_atpx_parse_functions(struct radeon_atpx_functions *f, u32 mask)
142{
143 f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
144 f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
145 f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
146 f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
147 f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
148 f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
149 f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
150 f->disp_detetion_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
151}
152
153/**
154 * radeon_atpx_validate() - validate ATPX functions
155 *
156 * @atpx: radeon atpx struct
157 *
158 * Validate that required functions are enabled (all asics).
159 * returns 0 on success, error on failure.
160 */
161static int radeon_atpx_validate(struct radeon_atpx *atpx)
162{
163 u32 valid_bits = 0;
164
165 if (atpx->functions.px_params) {
166 union acpi_object *info;
167 struct atpx_px_params output;
168 size_t size;
169
170 info = radeon_atpx_call(handle: atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
171 if (!info)
172 return -EIO;
173
174 memset(&output, 0, sizeof(output));
175
176 size = *(u16 *) info->buffer.pointer;
177 if (size < 10) {
178 pr_err("ATPX buffer is too small: %zu\n", size);
179 kfree(objp: info);
180 return -EINVAL;
181 }
182 size = min(sizeof(output), size);
183
184 memcpy(&output, info->buffer.pointer, size);
185
186 valid_bits = output.flags & output.valid_flags;
187
188 kfree(objp: info);
189 }
190
191 /* if separate mux flag is set, mux controls are required */
192 if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
193 atpx->functions.i2c_mux_cntl = true;
194 atpx->functions.disp_mux_cntl = true;
195 }
196 /* if any outputs are muxed, mux controls are required */
197 if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
198 ATPX_TV_SIGNAL_MUXED |
199 ATPX_DFP_SIGNAL_MUXED))
200 atpx->functions.disp_mux_cntl = true;
201
202 /* some bioses set these bits rather than flagging power_cntl as supported */
203 if (valid_bits & (ATPX_DYNAMIC_PX_SUPPORTED |
204 ATPX_DYNAMIC_DGPU_POWER_OFF_SUPPORTED))
205 atpx->functions.power_cntl = true;
206
207 atpx->is_hybrid = false;
208 if (valid_bits & ATPX_MS_HYBRID_GFX_SUPPORTED) {
209 pr_info("ATPX Hybrid Graphics\n");
210 /*
211 * Disable legacy PM methods only when pcie port PM is usable,
212 * otherwise the device might fail to power off or power on.
213 */
214 atpx->functions.power_cntl = !radeon_atpx_priv.bridge_pm_usable;
215 atpx->is_hybrid = true;
216 }
217
218 return 0;
219}
220
221/**
222 * radeon_atpx_verify_interface - verify ATPX
223 *
224 * @atpx: radeon atpx struct
225 *
226 * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
227 * to initialize ATPX and determine what features are supported
228 * (all asics).
229 * returns 0 on success, error on failure.
230 */
231static int radeon_atpx_verify_interface(struct radeon_atpx *atpx)
232{
233 union acpi_object *info;
234 struct atpx_verify_interface output;
235 size_t size;
236 int err = 0;
237
238 info = radeon_atpx_call(handle: atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
239 if (!info)
240 return -EIO;
241
242 memset(&output, 0, sizeof(output));
243
244 size = *(u16 *) info->buffer.pointer;
245 if (size < 8) {
246 pr_err("ATPX buffer is too small: %zu\n", size);
247 err = -EINVAL;
248 goto out;
249 }
250 size = min(sizeof(output), size);
251
252 memcpy(&output, info->buffer.pointer, size);
253
254 /* TODO: check version? */
255 pr_info("ATPX version %u, functions 0x%08x\n",
256 output.version, output.function_bits);
257
258 radeon_atpx_parse_functions(f: &atpx->functions, mask: output.function_bits);
259
260out:
261 kfree(objp: info);
262 return err;
263}
264
265/**
266 * radeon_atpx_set_discrete_state - power up/down discrete GPU
267 *
268 * @atpx: atpx info struct
269 * @state: discrete GPU state (0 = power down, 1 = power up)
270 *
271 * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
272 * power down/up the discrete GPU (all asics).
273 * Returns 0 on success, error on failure.
274 */
275static int radeon_atpx_set_discrete_state(struct radeon_atpx *atpx, u8 state)
276{
277 struct acpi_buffer params;
278 union acpi_object *info;
279 struct atpx_power_control input;
280
281 if (atpx->functions.power_cntl) {
282 input.size = 3;
283 input.dgpu_state = state;
284 params.length = input.size;
285 params.pointer = &input;
286 info = radeon_atpx_call(handle: atpx->handle,
287 ATPX_FUNCTION_POWER_CONTROL,
288 params: &params);
289 if (!info)
290 return -EIO;
291 kfree(objp: info);
292
293 /* 200ms delay is required after off */
294 if (state == 0)
295 msleep(msecs: 200);
296 }
297 return 0;
298}
299
300/**
301 * radeon_atpx_switch_disp_mux - switch display mux
302 *
303 * @atpx: atpx info struct
304 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
305 *
306 * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
307 * switch the display mux between the discrete GPU and integrated GPU
308 * (all asics).
309 * Returns 0 on success, error on failure.
310 */
311static int radeon_atpx_switch_disp_mux(struct radeon_atpx *atpx, u16 mux_id)
312{
313 struct acpi_buffer params;
314 union acpi_object *info;
315 struct atpx_mux input;
316
317 if (atpx->functions.disp_mux_cntl) {
318 input.size = 4;
319 input.mux = mux_id;
320 params.length = input.size;
321 params.pointer = &input;
322 info = radeon_atpx_call(handle: atpx->handle,
323 ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
324 params: &params);
325 if (!info)
326 return -EIO;
327 kfree(objp: info);
328 }
329 return 0;
330}
331
332/**
333 * radeon_atpx_switch_i2c_mux - switch i2c/hpd mux
334 *
335 * @atpx: atpx info struct
336 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
337 *
338 * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
339 * switch the i2c/hpd mux between the discrete GPU and integrated GPU
340 * (all asics).
341 * Returns 0 on success, error on failure.
342 */
343static int radeon_atpx_switch_i2c_mux(struct radeon_atpx *atpx, u16 mux_id)
344{
345 struct acpi_buffer params;
346 union acpi_object *info;
347 struct atpx_mux input;
348
349 if (atpx->functions.i2c_mux_cntl) {
350 input.size = 4;
351 input.mux = mux_id;
352 params.length = input.size;
353 params.pointer = &input;
354 info = radeon_atpx_call(handle: atpx->handle,
355 ATPX_FUNCTION_I2C_MUX_CONTROL,
356 params: &params);
357 if (!info)
358 return -EIO;
359 kfree(objp: info);
360 }
361 return 0;
362}
363
364/**
365 * radeon_atpx_switch_start - notify the sbios of a GPU switch
366 *
367 * @atpx: atpx info struct
368 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
369 *
370 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
371 * function to notify the sbios that a switch between the discrete GPU and
372 * integrated GPU has begun (all asics).
373 * Returns 0 on success, error on failure.
374 */
375static int radeon_atpx_switch_start(struct radeon_atpx *atpx, u16 mux_id)
376{
377 struct acpi_buffer params;
378 union acpi_object *info;
379 struct atpx_mux input;
380
381 if (atpx->functions.switch_start) {
382 input.size = 4;
383 input.mux = mux_id;
384 params.length = input.size;
385 params.pointer = &input;
386 info = radeon_atpx_call(handle: atpx->handle,
387 ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
388 params: &params);
389 if (!info)
390 return -EIO;
391 kfree(objp: info);
392 }
393 return 0;
394}
395
396/**
397 * radeon_atpx_switch_end - notify the sbios of a GPU switch
398 *
399 * @atpx: atpx info struct
400 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
401 *
402 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
403 * function to notify the sbios that a switch between the discrete GPU and
404 * integrated GPU has ended (all asics).
405 * Returns 0 on success, error on failure.
406 */
407static int radeon_atpx_switch_end(struct radeon_atpx *atpx, u16 mux_id)
408{
409 struct acpi_buffer params;
410 union acpi_object *info;
411 struct atpx_mux input;
412
413 if (atpx->functions.switch_end) {
414 input.size = 4;
415 input.mux = mux_id;
416 params.length = input.size;
417 params.pointer = &input;
418 info = radeon_atpx_call(handle: atpx->handle,
419 ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
420 params: &params);
421 if (!info)
422 return -EIO;
423 kfree(objp: info);
424 }
425 return 0;
426}
427
428/**
429 * radeon_atpx_switchto - switch to the requested GPU
430 *
431 * @id: GPU to switch to
432 *
433 * Execute the necessary ATPX functions to switch between the discrete GPU and
434 * integrated GPU (all asics).
435 * Returns 0 on success, error on failure.
436 */
437static int radeon_atpx_switchto(enum vga_switcheroo_client_id id)
438{
439 u16 gpu_id;
440
441 if (id == VGA_SWITCHEROO_IGD)
442 gpu_id = ATPX_INTEGRATED_GPU;
443 else
444 gpu_id = ATPX_DISCRETE_GPU;
445
446 radeon_atpx_switch_start(atpx: &radeon_atpx_priv.atpx, mux_id: gpu_id);
447 radeon_atpx_switch_disp_mux(atpx: &radeon_atpx_priv.atpx, mux_id: gpu_id);
448 radeon_atpx_switch_i2c_mux(atpx: &radeon_atpx_priv.atpx, mux_id: gpu_id);
449 radeon_atpx_switch_end(atpx: &radeon_atpx_priv.atpx, mux_id: gpu_id);
450
451 return 0;
452}
453
454/**
455 * radeon_atpx_power_state - power down/up the requested GPU
456 *
457 * @id: GPU to power down/up
458 * @state: requested power state (0 = off, 1 = on)
459 *
460 * Execute the necessary ATPX function to power down/up the discrete GPU
461 * (all asics).
462 * Returns 0 on success, error on failure.
463 */
464static int radeon_atpx_power_state(enum vga_switcheroo_client_id id,
465 enum vga_switcheroo_state state)
466{
467 /* on w500 ACPI can't change intel gpu state */
468 if (id == VGA_SWITCHEROO_IGD)
469 return 0;
470
471 radeon_atpx_set_discrete_state(atpx: &radeon_atpx_priv.atpx, state);
472 return 0;
473}
474
475/**
476 * radeon_atpx_pci_probe_handle - look up the ATPX handle
477 *
478 * @pdev: pci device
479 *
480 * Look up the ATPX handles (all asics).
481 * Returns true if the handles are found, false if not.
482 */
483static bool radeon_atpx_pci_probe_handle(struct pci_dev *pdev)
484{
485 acpi_handle dhandle, atpx_handle;
486 acpi_status status;
487
488 dhandle = ACPI_HANDLE(&pdev->dev);
489 if (!dhandle)
490 return false;
491
492 status = acpi_get_handle(parent: dhandle, pathname: "ATPX", ret_handle: &atpx_handle);
493 if (ACPI_FAILURE(status))
494 return false;
495
496 radeon_atpx_priv.dhandle = dhandle;
497 radeon_atpx_priv.atpx.handle = atpx_handle;
498 return true;
499}
500
501/**
502 * radeon_atpx_init - verify the ATPX interface
503 *
504 * Verify the ATPX interface (all asics).
505 * Returns 0 on success, error on failure.
506 */
507static int radeon_atpx_init(void)
508{
509 int r;
510
511 /* set up the ATPX handle */
512 r = radeon_atpx_verify_interface(atpx: &radeon_atpx_priv.atpx);
513 if (r)
514 return r;
515
516 /* validate the atpx setup */
517 r = radeon_atpx_validate(atpx: &radeon_atpx_priv.atpx);
518 if (r)
519 return r;
520
521 return 0;
522}
523
524/**
525 * radeon_atpx_get_client_id - get the client id
526 *
527 * @pdev: pci device
528 *
529 * look up whether we are the integrated or discrete GPU (all asics).
530 * Returns the client id.
531 */
532static enum vga_switcheroo_client_id radeon_atpx_get_client_id(struct pci_dev *pdev)
533{
534 if (radeon_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
535 return VGA_SWITCHEROO_IGD;
536 else
537 return VGA_SWITCHEROO_DIS;
538}
539
540static const struct vga_switcheroo_handler radeon_atpx_handler = {
541 .switchto = radeon_atpx_switchto,
542 .power_state = radeon_atpx_power_state,
543 .get_client_id = radeon_atpx_get_client_id,
544};
545
546/**
547 * radeon_atpx_detect - detect whether we have PX
548 *
549 * Check if we have a PX system (all asics).
550 * Returns true if we have a PX system, false if not.
551 */
552static bool radeon_atpx_detect(void)
553{
554 char acpi_method_name[255] = { 0 };
555 struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
556 struct pci_dev *pdev = NULL;
557 bool has_atpx = false;
558 int vga_count = 0;
559 bool d3_supported = false;
560 struct pci_dev *parent_pdev;
561
562 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, from: pdev)) != NULL) {
563 vga_count++;
564
565 has_atpx |= (radeon_atpx_pci_probe_handle(pdev) == true);
566
567 parent_pdev = pci_upstream_bridge(dev: pdev);
568 d3_supported |= parent_pdev && parent_pdev->bridge_d3;
569 }
570
571 /* some newer PX laptops mark the dGPU as a non-VGA display device */
572 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, from: pdev)) != NULL) {
573 vga_count++;
574
575 has_atpx |= (radeon_atpx_pci_probe_handle(pdev) == true);
576
577 parent_pdev = pci_upstream_bridge(dev: pdev);
578 d3_supported |= parent_pdev && parent_pdev->bridge_d3;
579 }
580
581 if (has_atpx && vga_count == 2) {
582 acpi_get_name(object: radeon_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, ret_path_ptr: &buffer);
583 pr_info("vga_switcheroo: detected switching method %s handle\n",
584 acpi_method_name);
585 radeon_atpx_priv.atpx_detected = true;
586 radeon_atpx_priv.bridge_pm_usable = d3_supported;
587 radeon_atpx_init();
588 return true;
589 }
590 return false;
591}
592
593/**
594 * radeon_register_atpx_handler - register with vga_switcheroo
595 *
596 * Register the PX callbacks with vga_switcheroo (all asics).
597 */
598void radeon_register_atpx_handler(void)
599{
600 bool r;
601 enum vga_switcheroo_handler_flags_t handler_flags = 0;
602
603 /* detect if we have any ATPX + 2 VGA in the system */
604 r = radeon_atpx_detect();
605 if (!r)
606 return;
607
608 vga_switcheroo_register_handler(handler: &radeon_atpx_handler, handler_flags);
609}
610
611/**
612 * radeon_unregister_atpx_handler - unregister with vga_switcheroo
613 *
614 * Unregister the PX callbacks with vga_switcheroo (all asics).
615 */
616void radeon_unregister_atpx_handler(void)
617{
618 vga_switcheroo_unregister_handler();
619}
620

source code of linux/drivers/gpu/drm/radeon/radeon_atpx_handler.c