Loading...
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 "amdgpu.h"
15#include "amd_acpi.h"
16
17#define AMDGPU_PX_QUIRK_FORCE_ATPX (1 << 0)
18
19struct amdgpu_px_quirk {
20 u32 chip_vendor;
21 u32 chip_device;
22 u32 subsys_vendor;
23 u32 subsys_device;
24 u32 px_quirk_flags;
25};
26
27struct amdgpu_atpx_functions {
28 bool px_params;
29 bool power_cntl;
30 bool disp_mux_cntl;
31 bool i2c_mux_cntl;
32 bool switch_start;
33 bool switch_end;
34 bool disp_connectors_mapping;
35 bool disp_detection_ports;
36};
37
38struct amdgpu_atpx {
39 acpi_handle handle;
40 struct amdgpu_atpx_functions functions;
41 bool is_hybrid;
42 bool dgpu_req_power_for_displays;
43};
44
45static struct amdgpu_atpx_priv {
46 bool atpx_detected;
47 bool bridge_pm_usable;
48 unsigned int quirks;
49 /* handle for device - and atpx */
50 acpi_handle dhandle;
51 acpi_handle other_handle;
52 struct amdgpu_atpx atpx;
53} amdgpu_atpx_priv;
54
55struct atpx_verify_interface {
56 u16 size; /* structure size in bytes (includes size field) */
57 u16 version; /* version */
58 u32 function_bits; /* supported functions bit vector */
59} __packed;
60
61struct atpx_px_params {
62 u16 size; /* structure size in bytes (includes size field) */
63 u32 valid_flags; /* which flags are valid */
64 u32 flags; /* flags */
65} __packed;
66
67struct atpx_power_control {
68 u16 size;
69 u8 dgpu_state;
70} __packed;
71
72struct atpx_mux {
73 u16 size;
74 u16 mux;
75} __packed;
76
77bool amdgpu_has_atpx(void)
78{
79 return amdgpu_atpx_priv.atpx_detected;
80}
81
82bool amdgpu_has_atpx_dgpu_power_cntl(void)
83{
84 return amdgpu_atpx_priv.atpx.functions.power_cntl;
85}
86
87bool amdgpu_is_atpx_hybrid(void)
88{
89 return amdgpu_atpx_priv.atpx.is_hybrid;
90}
91
92bool amdgpu_atpx_dgpu_req_power_for_displays(void)
93{
94 return amdgpu_atpx_priv.atpx.dgpu_req_power_for_displays;
95}
96
97#if defined(CONFIG_ACPI)
98void *amdgpu_atpx_get_dhandle(void)
99{
100 return amdgpu_atpx_priv.dhandle;
101}
102#endif
103
104/**
105 * amdgpu_atpx_call - call an ATPX method
106 *
107 * @handle: acpi handle
108 * @function: the ATPX function to execute
109 * @params: ATPX function params
110 *
111 * Executes the requested ATPX function (all asics).
112 * Returns a pointer to the acpi output buffer.
113 */
114static union acpi_object *amdgpu_atpx_call(acpi_handle handle, int function,
115 struct acpi_buffer *params)
116{
117 acpi_status status;
118 union acpi_object atpx_arg_elements[2];
119 struct acpi_object_list atpx_arg;
120 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
121
122 atpx_arg.count = 2;
123 atpx_arg.pointer = &atpx_arg_elements[0];
124
125 atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
126 atpx_arg_elements[0].integer.value = function;
127
128 if (params) {
129 atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
130 atpx_arg_elements[1].buffer.length = params->length;
131 atpx_arg_elements[1].buffer.pointer = params->pointer;
132 } else {
133 /* We need a second fake parameter */
134 atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
135 atpx_arg_elements[1].integer.value = 0;
136 }
137
138 status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);
139
140 /* Fail only if calling the method fails and ATPX is supported */
141 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
142 pr_err("failed to evaluate ATPX got %s\n",
143 acpi_format_exception(status));
144 kfree(buffer.pointer);
145 return NULL;
146 }
147
148 return buffer.pointer;
149}
150
151/**
152 * amdgpu_atpx_parse_functions - parse supported functions
153 *
154 * @f: supported functions struct
155 * @mask: supported functions mask from ATPX
156 *
157 * Use the supported functions mask from ATPX function
158 * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
159 * are supported (all asics).
160 */
161static void amdgpu_atpx_parse_functions(struct amdgpu_atpx_functions *f, u32 mask)
162{
163 f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
164 f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
165 f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
166 f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
167 f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
168 f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
169 f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
170 f->disp_detection_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
171}
172
173/**
174 * amdgpu_atpx_validate - validate ATPX functions
175 *
176 * @atpx: amdgpu atpx struct
177 *
178 * Validate that required functions are enabled (all asics).
179 * returns 0 on success, error on failure.
180 */
181static int amdgpu_atpx_validate(struct amdgpu_atpx *atpx)
182{
183 u32 valid_bits = 0;
184
185 if (atpx->functions.px_params) {
186 union acpi_object *info;
187 struct atpx_px_params output;
188 size_t size;
189
190 info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
191 if (!info)
192 return -EIO;
193
194 memset(&output, 0, sizeof(output));
195
196 size = *(u16 *) info->buffer.pointer;
197 if (size < 10) {
198 pr_err("ATPX buffer is too small: %zu\n", size);
199 kfree(info);
200 return -EINVAL;
201 }
202 size = min(sizeof(output), size);
203
204 memcpy(&output, info->buffer.pointer, size);
205
206 valid_bits = output.flags & output.valid_flags;
207
208 kfree(info);
209 }
210
211 /* if separate mux flag is set, mux controls are required */
212 if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
213 atpx->functions.i2c_mux_cntl = true;
214 atpx->functions.disp_mux_cntl = true;
215 }
216 /* if any outputs are muxed, mux controls are required */
217 if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
218 ATPX_TV_SIGNAL_MUXED |
219 ATPX_DFP_SIGNAL_MUXED))
220 atpx->functions.disp_mux_cntl = true;
221
222
223 /* some bioses set these bits rather than flagging power_cntl as supported */
224 if (valid_bits & (ATPX_DYNAMIC_PX_SUPPORTED |
225 ATPX_DYNAMIC_DGPU_POWER_OFF_SUPPORTED))
226 atpx->functions.power_cntl = true;
227
228 atpx->is_hybrid = false;
229 if (valid_bits & ATPX_MS_HYBRID_GFX_SUPPORTED) {
230 if (amdgpu_atpx_priv.quirks & AMDGPU_PX_QUIRK_FORCE_ATPX) {
231 pr_warn("ATPX Hybrid Graphics, forcing to ATPX\n");
232 atpx->functions.power_cntl = true;
233 atpx->is_hybrid = false;
234 } else {
235 pr_notice("ATPX Hybrid Graphics\n");
236 /*
237 * Disable legacy PM methods only when pcie port PM is usable,
238 * otherwise the device might fail to power off or power on.
239 */
240 atpx->functions.power_cntl = !amdgpu_atpx_priv.bridge_pm_usable;
241 atpx->is_hybrid = true;
242 }
243 }
244
245 atpx->dgpu_req_power_for_displays = false;
246 if (valid_bits & ATPX_DGPU_REQ_POWER_FOR_DISPLAYS)
247 atpx->dgpu_req_power_for_displays = true;
248
249 return 0;
250}
251
252/**
253 * amdgpu_atpx_verify_interface - verify ATPX
254 *
255 * @atpx: amdgpu atpx struct
256 *
257 * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
258 * to initialize ATPX and determine what features are supported
259 * (all asics).
260 * returns 0 on success, error on failure.
261 */
262static int amdgpu_atpx_verify_interface(struct amdgpu_atpx *atpx)
263{
264 union acpi_object *info;
265 struct atpx_verify_interface output;
266 size_t size;
267 int err = 0;
268
269 info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
270 if (!info)
271 return -EIO;
272
273 memset(&output, 0, sizeof(output));
274
275 size = *(u16 *) info->buffer.pointer;
276 if (size < 8) {
277 pr_err("ATPX buffer is too small: %zu\n", size);
278 err = -EINVAL;
279 goto out;
280 }
281 size = min(sizeof(output), size);
282
283 memcpy(&output, info->buffer.pointer, size);
284
285 /* TODO: check version? */
286 pr_notice("ATPX version %u, functions 0x%08x\n",
287 output.version, output.function_bits);
288
289 amdgpu_atpx_parse_functions(&atpx->functions, output.function_bits);
290
291out:
292 kfree(info);
293 return err;
294}
295
296/**
297 * amdgpu_atpx_set_discrete_state - power up/down discrete GPU
298 *
299 * @atpx: atpx info struct
300 * @state: discrete GPU state (0 = power down, 1 = power up)
301 *
302 * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
303 * power down/up the discrete GPU (all asics).
304 * Returns 0 on success, error on failure.
305 */
306static int amdgpu_atpx_set_discrete_state(struct amdgpu_atpx *atpx, u8 state)
307{
308 struct acpi_buffer params;
309 union acpi_object *info;
310 struct atpx_power_control input;
311
312 if (atpx->functions.power_cntl) {
313 input.size = 3;
314 input.dgpu_state = state;
315 params.length = input.size;
316 params.pointer = &input;
317 info = amdgpu_atpx_call(atpx->handle,
318 ATPX_FUNCTION_POWER_CONTROL,
319 ¶ms);
320 if (!info)
321 return -EIO;
322 kfree(info);
323
324 /* 200ms delay is required after off */
325 if (state == 0)
326 msleep(200);
327 }
328 return 0;
329}
330
331/**
332 * amdgpu_atpx_switch_disp_mux - switch display mux
333 *
334 * @atpx: atpx info struct
335 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
336 *
337 * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
338 * switch the display mux between the discrete GPU and integrated GPU
339 * (all asics).
340 * Returns 0 on success, error on failure.
341 */
342static int amdgpu_atpx_switch_disp_mux(struct amdgpu_atpx *atpx, u16 mux_id)
343{
344 struct acpi_buffer params;
345 union acpi_object *info;
346 struct atpx_mux input;
347
348 if (atpx->functions.disp_mux_cntl) {
349 input.size = 4;
350 input.mux = mux_id;
351 params.length = input.size;
352 params.pointer = &input;
353 info = amdgpu_atpx_call(atpx->handle,
354 ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
355 ¶ms);
356 if (!info)
357 return -EIO;
358 kfree(info);
359 }
360 return 0;
361}
362
363/**
364 * amdgpu_atpx_switch_i2c_mux - switch i2c/hpd mux
365 *
366 * @atpx: atpx info struct
367 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
368 *
369 * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
370 * switch the i2c/hpd mux between the discrete GPU and integrated GPU
371 * (all asics).
372 * Returns 0 on success, error on failure.
373 */
374static int amdgpu_atpx_switch_i2c_mux(struct amdgpu_atpx *atpx, u16 mux_id)
375{
376 struct acpi_buffer params;
377 union acpi_object *info;
378 struct atpx_mux input;
379
380 if (atpx->functions.i2c_mux_cntl) {
381 input.size = 4;
382 input.mux = mux_id;
383 params.length = input.size;
384 params.pointer = &input;
385 info = amdgpu_atpx_call(atpx->handle,
386 ATPX_FUNCTION_I2C_MUX_CONTROL,
387 ¶ms);
388 if (!info)
389 return -EIO;
390 kfree(info);
391 }
392 return 0;
393}
394
395/**
396 * amdgpu_atpx_switch_start - notify the sbios of a GPU switch
397 *
398 * @atpx: atpx info struct
399 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
400 *
401 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
402 * function to notify the sbios that a switch between the discrete GPU and
403 * integrated GPU has begun (all asics).
404 * Returns 0 on success, error on failure.
405 */
406static int amdgpu_atpx_switch_start(struct amdgpu_atpx *atpx, u16 mux_id)
407{
408 struct acpi_buffer params;
409 union acpi_object *info;
410 struct atpx_mux input;
411
412 if (atpx->functions.switch_start) {
413 input.size = 4;
414 input.mux = mux_id;
415 params.length = input.size;
416 params.pointer = &input;
417 info = amdgpu_atpx_call(atpx->handle,
418 ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
419 ¶ms);
420 if (!info)
421 return -EIO;
422 kfree(info);
423 }
424 return 0;
425}
426
427/**
428 * amdgpu_atpx_switch_end - notify the sbios of a GPU switch
429 *
430 * @atpx: atpx info struct
431 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
432 *
433 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
434 * function to notify the sbios that a switch between the discrete GPU and
435 * integrated GPU has ended (all asics).
436 * Returns 0 on success, error on failure.
437 */
438static int amdgpu_atpx_switch_end(struct amdgpu_atpx *atpx, u16 mux_id)
439{
440 struct acpi_buffer params;
441 union acpi_object *info;
442 struct atpx_mux input;
443
444 if (atpx->functions.switch_end) {
445 input.size = 4;
446 input.mux = mux_id;
447 params.length = input.size;
448 params.pointer = &input;
449 info = amdgpu_atpx_call(atpx->handle,
450 ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
451 ¶ms);
452 if (!info)
453 return -EIO;
454 kfree(info);
455 }
456 return 0;
457}
458
459/**
460 * amdgpu_atpx_switchto - switch to the requested GPU
461 *
462 * @id: GPU to switch to
463 *
464 * Execute the necessary ATPX functions to switch between the discrete GPU and
465 * integrated GPU (all asics).
466 * Returns 0 on success, error on failure.
467 */
468static int amdgpu_atpx_switchto(enum vga_switcheroo_client_id id)
469{
470 u16 gpu_id;
471
472 if (id == VGA_SWITCHEROO_IGD)
473 gpu_id = ATPX_INTEGRATED_GPU;
474 else
475 gpu_id = ATPX_DISCRETE_GPU;
476
477 amdgpu_atpx_switch_start(&amdgpu_atpx_priv.atpx, gpu_id);
478 amdgpu_atpx_switch_disp_mux(&amdgpu_atpx_priv.atpx, gpu_id);
479 amdgpu_atpx_switch_i2c_mux(&amdgpu_atpx_priv.atpx, gpu_id);
480 amdgpu_atpx_switch_end(&amdgpu_atpx_priv.atpx, gpu_id);
481
482 return 0;
483}
484
485/**
486 * amdgpu_atpx_power_state - power down/up the requested GPU
487 *
488 * @id: GPU to power down/up
489 * @state: requested power state (0 = off, 1 = on)
490 *
491 * Execute the necessary ATPX function to power down/up the discrete GPU
492 * (all asics).
493 * Returns 0 on success, error on failure.
494 */
495static int amdgpu_atpx_power_state(enum vga_switcheroo_client_id id,
496 enum vga_switcheroo_state state)
497{
498 /* on w500 ACPI can't change intel gpu state */
499 if (id == VGA_SWITCHEROO_IGD)
500 return 0;
501
502 amdgpu_atpx_set_discrete_state(&amdgpu_atpx_priv.atpx, state);
503 return 0;
504}
505
506/**
507 * amdgpu_atpx_pci_probe_handle - look up the ATPX handle
508 *
509 * @pdev: pci device
510 *
511 * Look up the ATPX handles (all asics).
512 * Returns true if the handles are found, false if not.
513 */
514static bool amdgpu_atpx_pci_probe_handle(struct pci_dev *pdev)
515{
516 acpi_handle dhandle, atpx_handle;
517 acpi_status status;
518
519 dhandle = ACPI_HANDLE(&pdev->dev);
520 if (!dhandle)
521 return false;
522
523 status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
524 if (ACPI_FAILURE(status)) {
525 amdgpu_atpx_priv.other_handle = dhandle;
526 return false;
527 }
528 amdgpu_atpx_priv.dhandle = dhandle;
529 amdgpu_atpx_priv.atpx.handle = atpx_handle;
530 return true;
531}
532
533/**
534 * amdgpu_atpx_init - verify the ATPX interface
535 *
536 * Verify the ATPX interface (all asics).
537 * Returns 0 on success, error on failure.
538 */
539static int amdgpu_atpx_init(void)
540{
541 int r;
542
543 /* set up the ATPX handle */
544 r = amdgpu_atpx_verify_interface(&amdgpu_atpx_priv.atpx);
545 if (r)
546 return r;
547
548 /* validate the atpx setup */
549 r = amdgpu_atpx_validate(&amdgpu_atpx_priv.atpx);
550 if (r)
551 return r;
552
553 return 0;
554}
555
556/**
557 * amdgpu_atpx_get_client_id - get the client id
558 *
559 * @pdev: pci device
560 *
561 * look up whether we are the integrated or discrete GPU (all asics).
562 * Returns the client id.
563 */
564static enum vga_switcheroo_client_id amdgpu_atpx_get_client_id(struct pci_dev *pdev)
565{
566 if (amdgpu_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
567 return VGA_SWITCHEROO_IGD;
568 else
569 return VGA_SWITCHEROO_DIS;
570}
571
572static const struct vga_switcheroo_handler amdgpu_atpx_handler = {
573 .switchto = amdgpu_atpx_switchto,
574 .power_state = amdgpu_atpx_power_state,
575 .get_client_id = amdgpu_atpx_get_client_id,
576};
577
578static const struct amdgpu_px_quirk amdgpu_px_quirk_list[] = {
579 /* HG _PR3 doesn't seem to work on this A+A weston board */
580 { 0x1002, 0x6900, 0x1002, 0x0124, AMDGPU_PX_QUIRK_FORCE_ATPX },
581 { 0x1002, 0x6900, 0x1028, 0x0812, AMDGPU_PX_QUIRK_FORCE_ATPX },
582 { 0x1002, 0x6900, 0x1028, 0x0813, AMDGPU_PX_QUIRK_FORCE_ATPX },
583 { 0x1002, 0x699f, 0x1028, 0x0814, AMDGPU_PX_QUIRK_FORCE_ATPX },
584 { 0x1002, 0x6900, 0x1025, 0x125A, AMDGPU_PX_QUIRK_FORCE_ATPX },
585 { 0x1002, 0x6900, 0x17AA, 0x3806, AMDGPU_PX_QUIRK_FORCE_ATPX },
586 { 0, 0, 0, 0, 0 },
587};
588
589static void amdgpu_atpx_get_quirks(struct pci_dev *pdev)
590{
591 const struct amdgpu_px_quirk *p = amdgpu_px_quirk_list;
592
593 /* Apply PX quirks */
594 while (p && p->chip_device != 0) {
595 if (pdev->vendor == p->chip_vendor &&
596 pdev->device == p->chip_device &&
597 pdev->subsystem_vendor == p->subsys_vendor &&
598 pdev->subsystem_device == p->subsys_device) {
599 amdgpu_atpx_priv.quirks |= p->px_quirk_flags;
600 break;
601 }
602 ++p;
603 }
604}
605
606/**
607 * amdgpu_atpx_detect - detect whether we have PX
608 *
609 * Check if we have a PX system (all asics).
610 * Returns true if we have a PX system, false if not.
611 */
612static bool amdgpu_atpx_detect(void)
613{
614 char acpi_method_name[255] = { 0 };
615 struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
616 struct pci_dev *pdev = NULL;
617 bool has_atpx = false;
618 int vga_count = 0;
619 bool d3_supported = false;
620 struct pci_dev *parent_pdev;
621
622 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
623 vga_count++;
624
625 has_atpx |= amdgpu_atpx_pci_probe_handle(pdev);
626
627 parent_pdev = pci_upstream_bridge(pdev);
628 d3_supported |= parent_pdev && parent_pdev->bridge_d3;
629 amdgpu_atpx_get_quirks(pdev);
630 }
631
632 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
633 vga_count++;
634
635 has_atpx |= amdgpu_atpx_pci_probe_handle(pdev);
636
637 parent_pdev = pci_upstream_bridge(pdev);
638 d3_supported |= parent_pdev && parent_pdev->bridge_d3;
639 amdgpu_atpx_get_quirks(pdev);
640 }
641
642 if (has_atpx && vga_count == 2) {
643 acpi_get_name(amdgpu_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
644 pr_info("vga_switcheroo: detected switching method %s handle\n",
645 acpi_method_name);
646 amdgpu_atpx_priv.atpx_detected = true;
647 amdgpu_atpx_priv.bridge_pm_usable = d3_supported;
648 amdgpu_atpx_init();
649 return true;
650 }
651 return false;
652}
653
654/**
655 * amdgpu_register_atpx_handler - register with vga_switcheroo
656 *
657 * Register the PX callbacks with vga_switcheroo (all asics).
658 */
659void amdgpu_register_atpx_handler(void)
660{
661 bool r;
662 enum vga_switcheroo_handler_flags_t handler_flags = 0;
663
664 /* detect if we have any ATPX + 2 VGA in the system */
665 r = amdgpu_atpx_detect();
666 if (!r)
667 return;
668
669 vga_switcheroo_register_handler(&amdgpu_atpx_handler, handler_flags);
670}
671
672/**
673 * amdgpu_unregister_atpx_handler - unregister with vga_switcheroo
674 *
675 * Unregister the PX callbacks with vga_switcheroo (all asics).
676 */
677void amdgpu_unregister_atpx_handler(void)
678{
679 vga_switcheroo_unregister_handler();
680}
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 "amd_acpi.h"
15
16struct amdgpu_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 amdgpu_atpx {
28 acpi_handle handle;
29 struct amdgpu_atpx_functions functions;
30};
31
32static struct amdgpu_atpx_priv {
33 bool atpx_detected;
34 /* handle for device - and atpx */
35 acpi_handle dhandle;
36 acpi_handle other_handle;
37 struct amdgpu_atpx atpx;
38} amdgpu_atpx_priv;
39
40struct 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
46struct 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
52struct atpx_power_control {
53 u16 size;
54 u8 dgpu_state;
55} __packed;
56
57struct atpx_mux {
58 u16 size;
59 u16 mux;
60} __packed;
61
62bool amdgpu_has_atpx(void) {
63 return amdgpu_atpx_priv.atpx_detected;
64}
65
66/**
67 * amdgpu_atpx_call - call an ATPX method
68 *
69 * @handle: acpi handle
70 * @function: the ATPX function to execute
71 * @params: ATPX function params
72 *
73 * Executes the requested ATPX function (all asics).
74 * Returns a pointer to the acpi output buffer.
75 */
76static union acpi_object *amdgpu_atpx_call(acpi_handle handle, int function,
77 struct acpi_buffer *params)
78{
79 acpi_status status;
80 union acpi_object atpx_arg_elements[2];
81 struct acpi_object_list atpx_arg;
82 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
83
84 atpx_arg.count = 2;
85 atpx_arg.pointer = &atpx_arg_elements[0];
86
87 atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
88 atpx_arg_elements[0].integer.value = function;
89
90 if (params) {
91 atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
92 atpx_arg_elements[1].buffer.length = params->length;
93 atpx_arg_elements[1].buffer.pointer = params->pointer;
94 } else {
95 /* We need a second fake parameter */
96 atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
97 atpx_arg_elements[1].integer.value = 0;
98 }
99
100 status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);
101
102 /* Fail only if calling the method fails and ATPX is supported */
103 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
104 printk("failed to evaluate ATPX got %s\n",
105 acpi_format_exception(status));
106 kfree(buffer.pointer);
107 return NULL;
108 }
109
110 return buffer.pointer;
111}
112
113/**
114 * amdgpu_atpx_parse_functions - parse supported functions
115 *
116 * @f: supported functions struct
117 * @mask: supported functions mask from ATPX
118 *
119 * Use the supported functions mask from ATPX function
120 * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
121 * are supported (all asics).
122 */
123static void amdgpu_atpx_parse_functions(struct amdgpu_atpx_functions *f, u32 mask)
124{
125 f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
126 f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
127 f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
128 f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
129 f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
130 f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
131 f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
132 f->disp_detetion_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
133}
134
135/**
136 * amdgpu_atpx_validate_functions - validate ATPX functions
137 *
138 * @atpx: amdgpu atpx struct
139 *
140 * Validate that required functions are enabled (all asics).
141 * returns 0 on success, error on failure.
142 */
143static int amdgpu_atpx_validate(struct amdgpu_atpx *atpx)
144{
145 /* make sure required functions are enabled */
146 /* dGPU power control is required */
147 if (atpx->functions.power_cntl == false) {
148 printk("ATPX dGPU power cntl not present, forcing\n");
149 atpx->functions.power_cntl = true;
150 }
151
152 if (atpx->functions.px_params) {
153 union acpi_object *info;
154 struct atpx_px_params output;
155 size_t size;
156 u32 valid_bits;
157
158 info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
159 if (!info)
160 return -EIO;
161
162 memset(&output, 0, sizeof(output));
163
164 size = *(u16 *) info->buffer.pointer;
165 if (size < 10) {
166 printk("ATPX buffer is too small: %zu\n", size);
167 kfree(info);
168 return -EINVAL;
169 }
170 size = min(sizeof(output), size);
171
172 memcpy(&output, info->buffer.pointer, size);
173
174 valid_bits = output.flags & output.valid_flags;
175 /* if separate mux flag is set, mux controls are required */
176 if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
177 atpx->functions.i2c_mux_cntl = true;
178 atpx->functions.disp_mux_cntl = true;
179 }
180 /* if any outputs are muxed, mux controls are required */
181 if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
182 ATPX_TV_SIGNAL_MUXED |
183 ATPX_DFP_SIGNAL_MUXED))
184 atpx->functions.disp_mux_cntl = true;
185
186 kfree(info);
187 }
188 return 0;
189}
190
191/**
192 * amdgpu_atpx_verify_interface - verify ATPX
193 *
194 * @atpx: amdgpu atpx struct
195 *
196 * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
197 * to initialize ATPX and determine what features are supported
198 * (all asics).
199 * returns 0 on success, error on failure.
200 */
201static int amdgpu_atpx_verify_interface(struct amdgpu_atpx *atpx)
202{
203 union acpi_object *info;
204 struct atpx_verify_interface output;
205 size_t size;
206 int err = 0;
207
208 info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
209 if (!info)
210 return -EIO;
211
212 memset(&output, 0, sizeof(output));
213
214 size = *(u16 *) info->buffer.pointer;
215 if (size < 8) {
216 printk("ATPX buffer is too small: %zu\n", size);
217 err = -EINVAL;
218 goto out;
219 }
220 size = min(sizeof(output), size);
221
222 memcpy(&output, info->buffer.pointer, size);
223
224 /* TODO: check version? */
225 printk("ATPX version %u, functions 0x%08x\n",
226 output.version, output.function_bits);
227
228 amdgpu_atpx_parse_functions(&atpx->functions, output.function_bits);
229
230out:
231 kfree(info);
232 return err;
233}
234
235/**
236 * amdgpu_atpx_set_discrete_state - power up/down discrete GPU
237 *
238 * @atpx: atpx info struct
239 * @state: discrete GPU state (0 = power down, 1 = power up)
240 *
241 * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
242 * power down/up the discrete GPU (all asics).
243 * Returns 0 on success, error on failure.
244 */
245static int amdgpu_atpx_set_discrete_state(struct amdgpu_atpx *atpx, u8 state)
246{
247 struct acpi_buffer params;
248 union acpi_object *info;
249 struct atpx_power_control input;
250
251 if (atpx->functions.power_cntl) {
252 input.size = 3;
253 input.dgpu_state = state;
254 params.length = input.size;
255 params.pointer = &input;
256 info = amdgpu_atpx_call(atpx->handle,
257 ATPX_FUNCTION_POWER_CONTROL,
258 ¶ms);
259 if (!info)
260 return -EIO;
261 kfree(info);
262 }
263 return 0;
264}
265
266/**
267 * amdgpu_atpx_switch_disp_mux - switch display mux
268 *
269 * @atpx: atpx info struct
270 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
271 *
272 * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
273 * switch the display mux between the discrete GPU and integrated GPU
274 * (all asics).
275 * Returns 0 on success, error on failure.
276 */
277static int amdgpu_atpx_switch_disp_mux(struct amdgpu_atpx *atpx, u16 mux_id)
278{
279 struct acpi_buffer params;
280 union acpi_object *info;
281 struct atpx_mux input;
282
283 if (atpx->functions.disp_mux_cntl) {
284 input.size = 4;
285 input.mux = mux_id;
286 params.length = input.size;
287 params.pointer = &input;
288 info = amdgpu_atpx_call(atpx->handle,
289 ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
290 ¶ms);
291 if (!info)
292 return -EIO;
293 kfree(info);
294 }
295 return 0;
296}
297
298/**
299 * amdgpu_atpx_switch_i2c_mux - switch i2c/hpd mux
300 *
301 * @atpx: atpx info struct
302 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
303 *
304 * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
305 * switch the i2c/hpd mux between the discrete GPU and integrated GPU
306 * (all asics).
307 * Returns 0 on success, error on failure.
308 */
309static int amdgpu_atpx_switch_i2c_mux(struct amdgpu_atpx *atpx, u16 mux_id)
310{
311 struct acpi_buffer params;
312 union acpi_object *info;
313 struct atpx_mux input;
314
315 if (atpx->functions.i2c_mux_cntl) {
316 input.size = 4;
317 input.mux = mux_id;
318 params.length = input.size;
319 params.pointer = &input;
320 info = amdgpu_atpx_call(atpx->handle,
321 ATPX_FUNCTION_I2C_MUX_CONTROL,
322 ¶ms);
323 if (!info)
324 return -EIO;
325 kfree(info);
326 }
327 return 0;
328}
329
330/**
331 * amdgpu_atpx_switch_start - notify the sbios of a GPU switch
332 *
333 * @atpx: atpx info struct
334 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
335 *
336 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
337 * function to notify the sbios that a switch between the discrete GPU and
338 * integrated GPU has begun (all asics).
339 * Returns 0 on success, error on failure.
340 */
341static int amdgpu_atpx_switch_start(struct amdgpu_atpx *atpx, u16 mux_id)
342{
343 struct acpi_buffer params;
344 union acpi_object *info;
345 struct atpx_mux input;
346
347 if (atpx->functions.switch_start) {
348 input.size = 4;
349 input.mux = mux_id;
350 params.length = input.size;
351 params.pointer = &input;
352 info = amdgpu_atpx_call(atpx->handle,
353 ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
354 ¶ms);
355 if (!info)
356 return -EIO;
357 kfree(info);
358 }
359 return 0;
360}
361
362/**
363 * amdgpu_atpx_switch_end - notify the sbios of a GPU switch
364 *
365 * @atpx: atpx info struct
366 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
367 *
368 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
369 * function to notify the sbios that a switch between the discrete GPU and
370 * integrated GPU has ended (all asics).
371 * Returns 0 on success, error on failure.
372 */
373static int amdgpu_atpx_switch_end(struct amdgpu_atpx *atpx, u16 mux_id)
374{
375 struct acpi_buffer params;
376 union acpi_object *info;
377 struct atpx_mux input;
378
379 if (atpx->functions.switch_end) {
380 input.size = 4;
381 input.mux = mux_id;
382 params.length = input.size;
383 params.pointer = &input;
384 info = amdgpu_atpx_call(atpx->handle,
385 ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
386 ¶ms);
387 if (!info)
388 return -EIO;
389 kfree(info);
390 }
391 return 0;
392}
393
394/**
395 * amdgpu_atpx_switchto - switch to the requested GPU
396 *
397 * @id: GPU to switch to
398 *
399 * Execute the necessary ATPX functions to switch between the discrete GPU and
400 * integrated GPU (all asics).
401 * Returns 0 on success, error on failure.
402 */
403static int amdgpu_atpx_switchto(enum vga_switcheroo_client_id id)
404{
405 u16 gpu_id;
406
407 if (id == VGA_SWITCHEROO_IGD)
408 gpu_id = ATPX_INTEGRATED_GPU;
409 else
410 gpu_id = ATPX_DISCRETE_GPU;
411
412 amdgpu_atpx_switch_start(&amdgpu_atpx_priv.atpx, gpu_id);
413 amdgpu_atpx_switch_disp_mux(&amdgpu_atpx_priv.atpx, gpu_id);
414 amdgpu_atpx_switch_i2c_mux(&amdgpu_atpx_priv.atpx, gpu_id);
415 amdgpu_atpx_switch_end(&amdgpu_atpx_priv.atpx, gpu_id);
416
417 return 0;
418}
419
420/**
421 * amdgpu_atpx_power_state - power down/up the requested GPU
422 *
423 * @id: GPU to power down/up
424 * @state: requested power state (0 = off, 1 = on)
425 *
426 * Execute the necessary ATPX function to power down/up the discrete GPU
427 * (all asics).
428 * Returns 0 on success, error on failure.
429 */
430static int amdgpu_atpx_power_state(enum vga_switcheroo_client_id id,
431 enum vga_switcheroo_state state)
432{
433 /* on w500 ACPI can't change intel gpu state */
434 if (id == VGA_SWITCHEROO_IGD)
435 return 0;
436
437 amdgpu_atpx_set_discrete_state(&amdgpu_atpx_priv.atpx, state);
438 return 0;
439}
440
441/**
442 * amdgpu_atpx_pci_probe_handle - look up the ATPX handle
443 *
444 * @pdev: pci device
445 *
446 * Look up the ATPX handles (all asics).
447 * Returns true if the handles are found, false if not.
448 */
449static bool amdgpu_atpx_pci_probe_handle(struct pci_dev *pdev)
450{
451 acpi_handle dhandle, atpx_handle;
452 acpi_status status;
453
454 dhandle = ACPI_HANDLE(&pdev->dev);
455 if (!dhandle)
456 return false;
457
458 status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
459 if (ACPI_FAILURE(status)) {
460 amdgpu_atpx_priv.other_handle = dhandle;
461 return false;
462 }
463 amdgpu_atpx_priv.dhandle = dhandle;
464 amdgpu_atpx_priv.atpx.handle = atpx_handle;
465 return true;
466}
467
468/**
469 * amdgpu_atpx_init - verify the ATPX interface
470 *
471 * Verify the ATPX interface (all asics).
472 * Returns 0 on success, error on failure.
473 */
474static int amdgpu_atpx_init(void)
475{
476 int r;
477
478 /* set up the ATPX handle */
479 r = amdgpu_atpx_verify_interface(&amdgpu_atpx_priv.atpx);
480 if (r)
481 return r;
482
483 /* validate the atpx setup */
484 r = amdgpu_atpx_validate(&amdgpu_atpx_priv.atpx);
485 if (r)
486 return r;
487
488 return 0;
489}
490
491/**
492 * amdgpu_atpx_get_client_id - get the client id
493 *
494 * @pdev: pci device
495 *
496 * look up whether we are the integrated or discrete GPU (all asics).
497 * Returns the client id.
498 */
499static int amdgpu_atpx_get_client_id(struct pci_dev *pdev)
500{
501 if (amdgpu_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
502 return VGA_SWITCHEROO_IGD;
503 else
504 return VGA_SWITCHEROO_DIS;
505}
506
507static const struct vga_switcheroo_handler amdgpu_atpx_handler = {
508 .switchto = amdgpu_atpx_switchto,
509 .power_state = amdgpu_atpx_power_state,
510 .init = amdgpu_atpx_init,
511 .get_client_id = amdgpu_atpx_get_client_id,
512};
513
514/**
515 * amdgpu_atpx_detect - detect whether we have PX
516 *
517 * Check if we have a PX system (all asics).
518 * Returns true if we have a PX system, false if not.
519 */
520static bool amdgpu_atpx_detect(void)
521{
522 char acpi_method_name[255] = { 0 };
523 struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
524 struct pci_dev *pdev = NULL;
525 bool has_atpx = false;
526 int vga_count = 0;
527
528 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
529 vga_count++;
530
531 has_atpx |= (amdgpu_atpx_pci_probe_handle(pdev) == true);
532 }
533
534 while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
535 vga_count++;
536
537 has_atpx |= (amdgpu_atpx_pci_probe_handle(pdev) == true);
538 }
539
540 if (has_atpx && vga_count == 2) {
541 acpi_get_name(amdgpu_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
542 printk(KERN_INFO "vga_switcheroo: detected switching method %s handle\n",
543 acpi_method_name);
544 amdgpu_atpx_priv.atpx_detected = true;
545 return true;
546 }
547 return false;
548}
549
550/**
551 * amdgpu_register_atpx_handler - register with vga_switcheroo
552 *
553 * Register the PX callbacks with vga_switcheroo (all asics).
554 */
555void amdgpu_register_atpx_handler(void)
556{
557 bool r;
558 enum vga_switcheroo_handler_flags_t handler_flags = 0;
559
560 /* detect if we have any ATPX + 2 VGA in the system */
561 r = amdgpu_atpx_detect();
562 if (!r)
563 return;
564
565 vga_switcheroo_register_handler(&amdgpu_atpx_handler, handler_flags);
566}
567
568/**
569 * amdgpu_unregister_atpx_handler - unregister with vga_switcheroo
570 *
571 * Unregister the PX callbacks with vga_switcheroo (all asics).
572 */
573void amdgpu_unregister_atpx_handler(void)
574{
575 vga_switcheroo_unregister_handler();
576}