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v4.17
  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#include <linux/delay.h>
 14
 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_detetion_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	return amdgpu_atpx_priv.atpx_detected;
 79}
 80
 81bool amdgpu_has_atpx_dgpu_power_cntl(void) {
 82	return amdgpu_atpx_priv.atpx.functions.power_cntl;
 83}
 84
 85bool amdgpu_is_atpx_hybrid(void) {
 86	return amdgpu_atpx_priv.atpx.is_hybrid;
 87}
 88
 89bool amdgpu_atpx_dgpu_req_power_for_displays(void) {
 90	return amdgpu_atpx_priv.atpx.dgpu_req_power_for_displays;
 91}
 92
 93/**
 94 * amdgpu_atpx_call - call an ATPX method
 95 *
 96 * @handle: acpi handle
 97 * @function: the ATPX function to execute
 98 * @params: ATPX function params
 99 *
100 * Executes the requested ATPX function (all asics).
101 * Returns a pointer to the acpi output buffer.
102 */
103static union acpi_object *amdgpu_atpx_call(acpi_handle handle, int function,
104					   struct acpi_buffer *params)
105{
106	acpi_status status;
107	union acpi_object atpx_arg_elements[2];
108	struct acpi_object_list atpx_arg;
109	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
110
111	atpx_arg.count = 2;
112	atpx_arg.pointer = &atpx_arg_elements[0];
113
114	atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
115	atpx_arg_elements[0].integer.value = function;
116
117	if (params) {
118		atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
119		atpx_arg_elements[1].buffer.length = params->length;
120		atpx_arg_elements[1].buffer.pointer = params->pointer;
121	} else {
122		/* We need a second fake parameter */
123		atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
124		atpx_arg_elements[1].integer.value = 0;
125	}
126
127	status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);
128
129	/* Fail only if calling the method fails and ATPX is supported */
130	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
131		printk("failed to evaluate ATPX got %s\n",
132		       acpi_format_exception(status));
133		kfree(buffer.pointer);
134		return NULL;
135	}
136
137	return buffer.pointer;
138}
139
140/**
141 * amdgpu_atpx_parse_functions - parse supported functions
142 *
143 * @f: supported functions struct
144 * @mask: supported functions mask from ATPX
145 *
146 * Use the supported functions mask from ATPX function
147 * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
148 * are supported (all asics).
149 */
150static void amdgpu_atpx_parse_functions(struct amdgpu_atpx_functions *f, u32 mask)
151{
152	f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
153	f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
154	f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
155	f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
156	f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
157	f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
158	f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
159	f->disp_detetion_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
160}
161
162/**
163 * amdgpu_atpx_validate_functions - validate ATPX functions
164 *
165 * @atpx: amdgpu atpx struct
166 *
167 * Validate that required functions are enabled (all asics).
168 * returns 0 on success, error on failure.
169 */
170static int amdgpu_atpx_validate(struct amdgpu_atpx *atpx)
171{
172	u32 valid_bits = 0;
173
174	if (atpx->functions.px_params) {
175		union acpi_object *info;
176		struct atpx_px_params output;
177		size_t size;
178
179		info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
180		if (!info)
181			return -EIO;
182
183		memset(&output, 0, sizeof(output));
184
185		size = *(u16 *) info->buffer.pointer;
186		if (size < 10) {
187			printk("ATPX buffer is too small: %zu\n", size);
188			kfree(info);
189			return -EINVAL;
190		}
191		size = min(sizeof(output), size);
192
193		memcpy(&output, info->buffer.pointer, size);
194
195		valid_bits = output.flags & output.valid_flags;
196
197		kfree(info);
198	}
199
200	/* if separate mux flag is set, mux controls are required */
201	if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
202		atpx->functions.i2c_mux_cntl = true;
203		atpx->functions.disp_mux_cntl = true;
204	}
205	/* if any outputs are muxed, mux controls are required */
206	if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
207			  ATPX_TV_SIGNAL_MUXED |
208			  ATPX_DFP_SIGNAL_MUXED))
209		atpx->functions.disp_mux_cntl = true;
210
211
212	/* some bioses set these bits rather than flagging power_cntl as supported */
213	if (valid_bits & (ATPX_DYNAMIC_PX_SUPPORTED |
214			  ATPX_DYNAMIC_DGPU_POWER_OFF_SUPPORTED))
215		atpx->functions.power_cntl = true;
216
217	atpx->is_hybrid = false;
218	if (valid_bits & ATPX_MS_HYBRID_GFX_SUPPORTED) {
219		if (amdgpu_atpx_priv.quirks & AMDGPU_PX_QUIRK_FORCE_ATPX) {
220			printk("ATPX Hybrid Graphics, forcing to ATPX\n");
221			atpx->functions.power_cntl = true;
222			atpx->is_hybrid = false;
223		} else {
224			printk("ATPX Hybrid Graphics\n");
225			/*
226			 * Disable legacy PM methods only when pcie port PM is usable,
227			 * otherwise the device might fail to power off or power on.
228			 */
229			atpx->functions.power_cntl = !amdgpu_atpx_priv.bridge_pm_usable;
230			atpx->is_hybrid = true;
231		}
232	}
233
234	atpx->dgpu_req_power_for_displays = false;
235	if (valid_bits & ATPX_DGPU_REQ_POWER_FOR_DISPLAYS)
236		atpx->dgpu_req_power_for_displays = true;
237
238	return 0;
239}
240
241/**
242 * amdgpu_atpx_verify_interface - verify ATPX
243 *
244 * @atpx: amdgpu atpx struct
245 *
246 * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
247 * to initialize ATPX and determine what features are supported
248 * (all asics).
249 * returns 0 on success, error on failure.
250 */
251static int amdgpu_atpx_verify_interface(struct amdgpu_atpx *atpx)
252{
253	union acpi_object *info;
254	struct atpx_verify_interface output;
255	size_t size;
256	int err = 0;
257
258	info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
259	if (!info)
260		return -EIO;
261
262	memset(&output, 0, sizeof(output));
263
264	size = *(u16 *) info->buffer.pointer;
265	if (size < 8) {
266		printk("ATPX buffer is too small: %zu\n", size);
267		err = -EINVAL;
268		goto out;
269	}
270	size = min(sizeof(output), size);
271
272	memcpy(&output, info->buffer.pointer, size);
273
274	/* TODO: check version? */
275	printk("ATPX version %u, functions 0x%08x\n",
276	       output.version, output.function_bits);
277
278	amdgpu_atpx_parse_functions(&atpx->functions, output.function_bits);
279
280out:
281	kfree(info);
282	return err;
283}
284
285/**
286 * amdgpu_atpx_set_discrete_state - power up/down discrete GPU
287 *
288 * @atpx: atpx info struct
289 * @state: discrete GPU state (0 = power down, 1 = power up)
290 *
291 * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
292 * power down/up the discrete GPU (all asics).
293 * Returns 0 on success, error on failure.
294 */
295static int amdgpu_atpx_set_discrete_state(struct amdgpu_atpx *atpx, u8 state)
296{
297	struct acpi_buffer params;
298	union acpi_object *info;
299	struct atpx_power_control input;
300
301	if (atpx->functions.power_cntl) {
302		input.size = 3;
303		input.dgpu_state = state;
304		params.length = input.size;
305		params.pointer = &input;
306		info = amdgpu_atpx_call(atpx->handle,
307					ATPX_FUNCTION_POWER_CONTROL,
308					&params);
309		if (!info)
310			return -EIO;
311		kfree(info);
312
313		/* 200ms delay is required after off */
314		if (state == 0)
315			msleep(200);
316	}
317	return 0;
318}
319
320/**
321 * amdgpu_atpx_switch_disp_mux - switch display mux
322 *
323 * @atpx: atpx info struct
324 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
325 *
326 * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
327 * switch the display mux between the discrete GPU and integrated GPU
328 * (all asics).
329 * Returns 0 on success, error on failure.
330 */
331static int amdgpu_atpx_switch_disp_mux(struct amdgpu_atpx *atpx, u16 mux_id)
332{
333	struct acpi_buffer params;
334	union acpi_object *info;
335	struct atpx_mux input;
336
337	if (atpx->functions.disp_mux_cntl) {
338		input.size = 4;
339		input.mux = mux_id;
340		params.length = input.size;
341		params.pointer = &input;
342		info = amdgpu_atpx_call(atpx->handle,
343					ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
344					&params);
345		if (!info)
346			return -EIO;
347		kfree(info);
348	}
349	return 0;
350}
351
352/**
353 * amdgpu_atpx_switch_i2c_mux - switch i2c/hpd mux
354 *
355 * @atpx: atpx info struct
356 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
357 *
358 * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
359 * switch the i2c/hpd mux between the discrete GPU and integrated GPU
360 * (all asics).
361 * Returns 0 on success, error on failure.
362 */
363static int amdgpu_atpx_switch_i2c_mux(struct amdgpu_atpx *atpx, u16 mux_id)
364{
365	struct acpi_buffer params;
366	union acpi_object *info;
367	struct atpx_mux input;
368
369	if (atpx->functions.i2c_mux_cntl) {
370		input.size = 4;
371		input.mux = mux_id;
372		params.length = input.size;
373		params.pointer = &input;
374		info = amdgpu_atpx_call(atpx->handle,
375					ATPX_FUNCTION_I2C_MUX_CONTROL,
376					&params);
377		if (!info)
378			return -EIO;
379		kfree(info);
380	}
381	return 0;
382}
383
384/**
385 * amdgpu_atpx_switch_start - notify the sbios of a GPU switch
386 *
387 * @atpx: atpx info struct
388 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
389 *
390 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
391 * function to notify the sbios that a switch between the discrete GPU and
392 * integrated GPU has begun (all asics).
393 * Returns 0 on success, error on failure.
394 */
395static int amdgpu_atpx_switch_start(struct amdgpu_atpx *atpx, u16 mux_id)
396{
397	struct acpi_buffer params;
398	union acpi_object *info;
399	struct atpx_mux input;
400
401	if (atpx->functions.switch_start) {
402		input.size = 4;
403		input.mux = mux_id;
404		params.length = input.size;
405		params.pointer = &input;
406		info = amdgpu_atpx_call(atpx->handle,
407					ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
408					&params);
409		if (!info)
410			return -EIO;
411		kfree(info);
412	}
413	return 0;
414}
415
416/**
417 * amdgpu_atpx_switch_end - notify the sbios of a GPU switch
418 *
419 * @atpx: atpx info struct
420 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
421 *
422 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
423 * function to notify the sbios that a switch between the discrete GPU and
424 * integrated GPU has ended (all asics).
425 * Returns 0 on success, error on failure.
426 */
427static int amdgpu_atpx_switch_end(struct amdgpu_atpx *atpx, u16 mux_id)
428{
429	struct acpi_buffer params;
430	union acpi_object *info;
431	struct atpx_mux input;
432
433	if (atpx->functions.switch_end) {
434		input.size = 4;
435		input.mux = mux_id;
436		params.length = input.size;
437		params.pointer = &input;
438		info = amdgpu_atpx_call(atpx->handle,
439					ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
440					&params);
441		if (!info)
442			return -EIO;
443		kfree(info);
444	}
445	return 0;
446}
447
448/**
449 * amdgpu_atpx_switchto - switch to the requested GPU
450 *
451 * @id: GPU to switch to
452 *
453 * Execute the necessary ATPX functions to switch between the discrete GPU and
454 * integrated GPU (all asics).
455 * Returns 0 on success, error on failure.
456 */
457static int amdgpu_atpx_switchto(enum vga_switcheroo_client_id id)
458{
459	u16 gpu_id;
460
461	if (id == VGA_SWITCHEROO_IGD)
462		gpu_id = ATPX_INTEGRATED_GPU;
463	else
464		gpu_id = ATPX_DISCRETE_GPU;
465
466	amdgpu_atpx_switch_start(&amdgpu_atpx_priv.atpx, gpu_id);
467	amdgpu_atpx_switch_disp_mux(&amdgpu_atpx_priv.atpx, gpu_id);
468	amdgpu_atpx_switch_i2c_mux(&amdgpu_atpx_priv.atpx, gpu_id);
469	amdgpu_atpx_switch_end(&amdgpu_atpx_priv.atpx, gpu_id);
470
471	return 0;
472}
473
474/**
475 * amdgpu_atpx_power_state - power down/up the requested GPU
476 *
477 * @id: GPU to power down/up
478 * @state: requested power state (0 = off, 1 = on)
479 *
480 * Execute the necessary ATPX function to power down/up the discrete GPU
481 * (all asics).
482 * Returns 0 on success, error on failure.
483 */
484static int amdgpu_atpx_power_state(enum vga_switcheroo_client_id id,
485				   enum vga_switcheroo_state state)
486{
487	/* on w500 ACPI can't change intel gpu state */
488	if (id == VGA_SWITCHEROO_IGD)
489		return 0;
490
491	amdgpu_atpx_set_discrete_state(&amdgpu_atpx_priv.atpx, state);
492	return 0;
493}
494
495/**
496 * amdgpu_atpx_pci_probe_handle - look up the ATPX handle
497 *
498 * @pdev: pci device
499 *
500 * Look up the ATPX handles (all asics).
501 * Returns true if the handles are found, false if not.
502 */
503static bool amdgpu_atpx_pci_probe_handle(struct pci_dev *pdev)
504{
505	acpi_handle dhandle, atpx_handle;
506	acpi_status status;
507
508	dhandle = ACPI_HANDLE(&pdev->dev);
509	if (!dhandle)
510		return false;
511
512	status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
513	if (ACPI_FAILURE(status)) {
514		amdgpu_atpx_priv.other_handle = dhandle;
515		return false;
516	}
517	amdgpu_atpx_priv.dhandle = dhandle;
518	amdgpu_atpx_priv.atpx.handle = atpx_handle;
519	return true;
520}
521
522/**
523 * amdgpu_atpx_init - verify the ATPX interface
524 *
525 * Verify the ATPX interface (all asics).
526 * Returns 0 on success, error on failure.
527 */
528static int amdgpu_atpx_init(void)
529{
530	int r;
531
532	/* set up the ATPX handle */
533	r = amdgpu_atpx_verify_interface(&amdgpu_atpx_priv.atpx);
534	if (r)
535		return r;
536
537	/* validate the atpx setup */
538	r = amdgpu_atpx_validate(&amdgpu_atpx_priv.atpx);
539	if (r)
540		return r;
541
542	return 0;
543}
544
545/**
546 * amdgpu_atpx_get_client_id - get the client id
547 *
548 * @pdev: pci device
549 *
550 * look up whether we are the integrated or discrete GPU (all asics).
551 * Returns the client id.
552 */
553static int amdgpu_atpx_get_client_id(struct pci_dev *pdev)
554{
555	if (amdgpu_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
556		return VGA_SWITCHEROO_IGD;
557	else
558		return VGA_SWITCHEROO_DIS;
559}
560
561static const struct vga_switcheroo_handler amdgpu_atpx_handler = {
562	.switchto = amdgpu_atpx_switchto,
563	.power_state = amdgpu_atpx_power_state,
564	.get_client_id = amdgpu_atpx_get_client_id,
565};
566
567static const struct amdgpu_px_quirk amdgpu_px_quirk_list[] = {
568	/* HG _PR3 doesn't seem to work on this A+A weston board */
569	{ 0x1002, 0x6900, 0x1002, 0x0124, AMDGPU_PX_QUIRK_FORCE_ATPX },
570	{ 0x1002, 0x6900, 0x1028, 0x0812, AMDGPU_PX_QUIRK_FORCE_ATPX },
571	{ 0x1002, 0x6900, 0x1028, 0x0813, AMDGPU_PX_QUIRK_FORCE_ATPX },
572	{ 0x1002, 0x67DF, 0x1028, 0x0774, AMDGPU_PX_QUIRK_FORCE_ATPX },
573	{ 0, 0, 0, 0, 0 },
574};
575
576static void amdgpu_atpx_get_quirks(struct pci_dev *pdev)
577{
578	const struct amdgpu_px_quirk *p = amdgpu_px_quirk_list;
579
580	/* Apply PX quirks */
581	while (p && p->chip_device != 0) {
582		if (pdev->vendor == p->chip_vendor &&
583		    pdev->device == p->chip_device &&
584		    pdev->subsystem_vendor == p->subsys_vendor &&
585		    pdev->subsystem_device == p->subsys_device) {
586			amdgpu_atpx_priv.quirks |= p->px_quirk_flags;
587			break;
588		}
589		++p;
590	}
591}
592
593/**
594 * amdgpu_atpx_detect - detect whether we have PX
595 *
596 * Check if we have a PX system (all asics).
597 * Returns true if we have a PX system, false if not.
598 */
599static bool amdgpu_atpx_detect(void)
600{
601	char acpi_method_name[255] = { 0 };
602	struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
603	struct pci_dev *pdev = NULL;
604	bool has_atpx = false;
605	int vga_count = 0;
606	bool d3_supported = false;
607	struct pci_dev *parent_pdev;
608
609	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
610		vga_count++;
611
612		has_atpx |= (amdgpu_atpx_pci_probe_handle(pdev) == true);
613
614		parent_pdev = pci_upstream_bridge(pdev);
615		d3_supported |= parent_pdev && parent_pdev->bridge_d3;
616		amdgpu_atpx_get_quirks(pdev);
617	}
618
619	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
620		vga_count++;
621
622		has_atpx |= (amdgpu_atpx_pci_probe_handle(pdev) == true);
623
624		parent_pdev = pci_upstream_bridge(pdev);
625		d3_supported |= parent_pdev && parent_pdev->bridge_d3;
626		amdgpu_atpx_get_quirks(pdev);
627	}
628
629	if (has_atpx && vga_count == 2) {
630		acpi_get_name(amdgpu_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
631		pr_info("vga_switcheroo: detected switching method %s handle\n",
632			acpi_method_name);
633		amdgpu_atpx_priv.atpx_detected = true;
634		amdgpu_atpx_priv.bridge_pm_usable = d3_supported;
635		amdgpu_atpx_init();
636		return true;
637	}
638	return false;
639}
640
641/**
642 * amdgpu_register_atpx_handler - register with vga_switcheroo
643 *
644 * Register the PX callbacks with vga_switcheroo (all asics).
645 */
646void amdgpu_register_atpx_handler(void)
647{
648	bool r;
649	enum vga_switcheroo_handler_flags_t handler_flags = 0;
650
651	/* detect if we have any ATPX + 2 VGA in the system */
652	r = amdgpu_atpx_detect();
653	if (!r)
654		return;
655
656	vga_switcheroo_register_handler(&amdgpu_atpx_handler, handler_flags);
657}
658
659/**
660 * amdgpu_unregister_atpx_handler - unregister with vga_switcheroo
661 *
662 * Unregister the PX callbacks with vga_switcheroo (all asics).
663 */
664void amdgpu_unregister_atpx_handler(void)
665{
666	vga_switcheroo_unregister_handler();
667}
v4.10.11
  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#include <linux/delay.h>
 14
 15#include "amd_acpi.h"
 16
 
 
 
 
 
 
 
 
 
 
 17struct amdgpu_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
 28struct amdgpu_atpx {
 29	acpi_handle handle;
 30	struct amdgpu_atpx_functions functions;
 31	bool is_hybrid;
 32	bool dgpu_req_power_for_displays;
 33};
 34
 35static struct amdgpu_atpx_priv {
 36	bool atpx_detected;
 37	bool bridge_pm_usable;
 
 38	/* handle for device - and atpx */
 39	acpi_handle dhandle;
 40	acpi_handle other_handle;
 41	struct amdgpu_atpx atpx;
 42} amdgpu_atpx_priv;
 43
 44struct atpx_verify_interface {
 45	u16 size;		/* structure size in bytes (includes size field) */
 46	u16 version;		/* version */
 47	u32 function_bits;	/* supported functions bit vector */
 48} __packed;
 49
 50struct atpx_px_params {
 51	u16 size;		/* structure size in bytes (includes size field) */
 52	u32 valid_flags;	/* which flags are valid */
 53	u32 flags;		/* flags */
 54} __packed;
 55
 56struct atpx_power_control {
 57	u16 size;
 58	u8 dgpu_state;
 59} __packed;
 60
 61struct atpx_mux {
 62	u16 size;
 63	u16 mux;
 64} __packed;
 65
 66bool amdgpu_has_atpx(void) {
 67	return amdgpu_atpx_priv.atpx_detected;
 68}
 69
 70bool amdgpu_has_atpx_dgpu_power_cntl(void) {
 71	return amdgpu_atpx_priv.atpx.functions.power_cntl;
 72}
 73
 74bool amdgpu_is_atpx_hybrid(void) {
 75	return amdgpu_atpx_priv.atpx.is_hybrid;
 76}
 77
 78bool amdgpu_atpx_dgpu_req_power_for_displays(void) {
 79	return amdgpu_atpx_priv.atpx.dgpu_req_power_for_displays;
 80}
 81
 82/**
 83 * amdgpu_atpx_call - call an ATPX method
 84 *
 85 * @handle: acpi handle
 86 * @function: the ATPX function to execute
 87 * @params: ATPX function params
 88 *
 89 * Executes the requested ATPX function (all asics).
 90 * Returns a pointer to the acpi output buffer.
 91 */
 92static union acpi_object *amdgpu_atpx_call(acpi_handle handle, int function,
 93					   struct acpi_buffer *params)
 94{
 95	acpi_status status;
 96	union acpi_object atpx_arg_elements[2];
 97	struct acpi_object_list atpx_arg;
 98	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 99
100	atpx_arg.count = 2;
101	atpx_arg.pointer = &atpx_arg_elements[0];
102
103	atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
104	atpx_arg_elements[0].integer.value = function;
105
106	if (params) {
107		atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
108		atpx_arg_elements[1].buffer.length = params->length;
109		atpx_arg_elements[1].buffer.pointer = params->pointer;
110	} else {
111		/* We need a second fake parameter */
112		atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
113		atpx_arg_elements[1].integer.value = 0;
114	}
115
116	status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);
117
118	/* Fail only if calling the method fails and ATPX is supported */
119	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
120		printk("failed to evaluate ATPX got %s\n",
121		       acpi_format_exception(status));
122		kfree(buffer.pointer);
123		return NULL;
124	}
125
126	return buffer.pointer;
127}
128
129/**
130 * amdgpu_atpx_parse_functions - parse supported functions
131 *
132 * @f: supported functions struct
133 * @mask: supported functions mask from ATPX
134 *
135 * Use the supported functions mask from ATPX function
136 * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
137 * are supported (all asics).
138 */
139static void amdgpu_atpx_parse_functions(struct amdgpu_atpx_functions *f, u32 mask)
140{
141	f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
142	f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
143	f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
144	f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
145	f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
146	f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
147	f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
148	f->disp_detetion_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
149}
150
151/**
152 * amdgpu_atpx_validate_functions - validate ATPX functions
153 *
154 * @atpx: amdgpu atpx struct
155 *
156 * Validate that required functions are enabled (all asics).
157 * returns 0 on success, error on failure.
158 */
159static int amdgpu_atpx_validate(struct amdgpu_atpx *atpx)
160{
161	u32 valid_bits = 0;
162
163	if (atpx->functions.px_params) {
164		union acpi_object *info;
165		struct atpx_px_params output;
166		size_t size;
167
168		info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
169		if (!info)
170			return -EIO;
171
172		memset(&output, 0, sizeof(output));
173
174		size = *(u16 *) info->buffer.pointer;
175		if (size < 10) {
176			printk("ATPX buffer is too small: %zu\n", size);
177			kfree(info);
178			return -EINVAL;
179		}
180		size = min(sizeof(output), size);
181
182		memcpy(&output, info->buffer.pointer, size);
183
184		valid_bits = output.flags & output.valid_flags;
185
186		kfree(info);
187	}
188
189	/* if separate mux flag is set, mux controls are required */
190	if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
191		atpx->functions.i2c_mux_cntl = true;
192		atpx->functions.disp_mux_cntl = true;
193	}
194	/* if any outputs are muxed, mux controls are required */
195	if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
196			  ATPX_TV_SIGNAL_MUXED |
197			  ATPX_DFP_SIGNAL_MUXED))
198		atpx->functions.disp_mux_cntl = true;
199
200
201	/* some bioses set these bits rather than flagging power_cntl as supported */
202	if (valid_bits & (ATPX_DYNAMIC_PX_SUPPORTED |
203			  ATPX_DYNAMIC_DGPU_POWER_OFF_SUPPORTED))
204		atpx->functions.power_cntl = true;
205
206	atpx->is_hybrid = false;
207	if (valid_bits & ATPX_MS_HYBRID_GFX_SUPPORTED) {
208		printk("ATPX Hybrid Graphics\n");
209		/*
210		 * Disable legacy PM methods only when pcie port PM is usable,
211		 * otherwise the device might fail to power off or power on.
212		 */
213		atpx->functions.power_cntl = !amdgpu_atpx_priv.bridge_pm_usable;
214		atpx->is_hybrid = true;
 
 
 
 
 
 
215	}
216
217	atpx->dgpu_req_power_for_displays = false;
218	if (valid_bits & ATPX_DGPU_REQ_POWER_FOR_DISPLAYS)
219		atpx->dgpu_req_power_for_displays = true;
220
221	return 0;
222}
223
224/**
225 * amdgpu_atpx_verify_interface - verify ATPX
226 *
227 * @atpx: amdgpu atpx struct
228 *
229 * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
230 * to initialize ATPX and determine what features are supported
231 * (all asics).
232 * returns 0 on success, error on failure.
233 */
234static int amdgpu_atpx_verify_interface(struct amdgpu_atpx *atpx)
235{
236	union acpi_object *info;
237	struct atpx_verify_interface output;
238	size_t size;
239	int err = 0;
240
241	info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
242	if (!info)
243		return -EIO;
244
245	memset(&output, 0, sizeof(output));
246
247	size = *(u16 *) info->buffer.pointer;
248	if (size < 8) {
249		printk("ATPX buffer is too small: %zu\n", size);
250		err = -EINVAL;
251		goto out;
252	}
253	size = min(sizeof(output), size);
254
255	memcpy(&output, info->buffer.pointer, size);
256
257	/* TODO: check version? */
258	printk("ATPX version %u, functions 0x%08x\n",
259	       output.version, output.function_bits);
260
261	amdgpu_atpx_parse_functions(&atpx->functions, output.function_bits);
262
263out:
264	kfree(info);
265	return err;
266}
267
268/**
269 * amdgpu_atpx_set_discrete_state - power up/down discrete GPU
270 *
271 * @atpx: atpx info struct
272 * @state: discrete GPU state (0 = power down, 1 = power up)
273 *
274 * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
275 * power down/up the discrete GPU (all asics).
276 * Returns 0 on success, error on failure.
277 */
278static int amdgpu_atpx_set_discrete_state(struct amdgpu_atpx *atpx, u8 state)
279{
280	struct acpi_buffer params;
281	union acpi_object *info;
282	struct atpx_power_control input;
283
284	if (atpx->functions.power_cntl) {
285		input.size = 3;
286		input.dgpu_state = state;
287		params.length = input.size;
288		params.pointer = &input;
289		info = amdgpu_atpx_call(atpx->handle,
290					ATPX_FUNCTION_POWER_CONTROL,
291					&params);
292		if (!info)
293			return -EIO;
294		kfree(info);
295
296		/* 200ms delay is required after off */
297		if (state == 0)
298			msleep(200);
299	}
300	return 0;
301}
302
303/**
304 * amdgpu_atpx_switch_disp_mux - switch display mux
305 *
306 * @atpx: atpx info struct
307 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
308 *
309 * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
310 * switch the display mux between the discrete GPU and integrated GPU
311 * (all asics).
312 * Returns 0 on success, error on failure.
313 */
314static int amdgpu_atpx_switch_disp_mux(struct amdgpu_atpx *atpx, u16 mux_id)
315{
316	struct acpi_buffer params;
317	union acpi_object *info;
318	struct atpx_mux input;
319
320	if (atpx->functions.disp_mux_cntl) {
321		input.size = 4;
322		input.mux = mux_id;
323		params.length = input.size;
324		params.pointer = &input;
325		info = amdgpu_atpx_call(atpx->handle,
326					ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
327					&params);
328		if (!info)
329			return -EIO;
330		kfree(info);
331	}
332	return 0;
333}
334
335/**
336 * amdgpu_atpx_switch_i2c_mux - switch i2c/hpd mux
337 *
338 * @atpx: atpx info struct
339 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
340 *
341 * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
342 * switch the i2c/hpd mux between the discrete GPU and integrated GPU
343 * (all asics).
344 * Returns 0 on success, error on failure.
345 */
346static int amdgpu_atpx_switch_i2c_mux(struct amdgpu_atpx *atpx, u16 mux_id)
347{
348	struct acpi_buffer params;
349	union acpi_object *info;
350	struct atpx_mux input;
351
352	if (atpx->functions.i2c_mux_cntl) {
353		input.size = 4;
354		input.mux = mux_id;
355		params.length = input.size;
356		params.pointer = &input;
357		info = amdgpu_atpx_call(atpx->handle,
358					ATPX_FUNCTION_I2C_MUX_CONTROL,
359					&params);
360		if (!info)
361			return -EIO;
362		kfree(info);
363	}
364	return 0;
365}
366
367/**
368 * amdgpu_atpx_switch_start - notify the sbios of a GPU switch
369 *
370 * @atpx: atpx info struct
371 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
372 *
373 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
374 * function to notify the sbios that a switch between the discrete GPU and
375 * integrated GPU has begun (all asics).
376 * Returns 0 on success, error on failure.
377 */
378static int amdgpu_atpx_switch_start(struct amdgpu_atpx *atpx, u16 mux_id)
379{
380	struct acpi_buffer params;
381	union acpi_object *info;
382	struct atpx_mux input;
383
384	if (atpx->functions.switch_start) {
385		input.size = 4;
386		input.mux = mux_id;
387		params.length = input.size;
388		params.pointer = &input;
389		info = amdgpu_atpx_call(atpx->handle,
390					ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
391					&params);
392		if (!info)
393			return -EIO;
394		kfree(info);
395	}
396	return 0;
397}
398
399/**
400 * amdgpu_atpx_switch_end - notify the sbios of a GPU switch
401 *
402 * @atpx: atpx info struct
403 * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
404 *
405 * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
406 * function to notify the sbios that a switch between the discrete GPU and
407 * integrated GPU has ended (all asics).
408 * Returns 0 on success, error on failure.
409 */
410static int amdgpu_atpx_switch_end(struct amdgpu_atpx *atpx, u16 mux_id)
411{
412	struct acpi_buffer params;
413	union acpi_object *info;
414	struct atpx_mux input;
415
416	if (atpx->functions.switch_end) {
417		input.size = 4;
418		input.mux = mux_id;
419		params.length = input.size;
420		params.pointer = &input;
421		info = amdgpu_atpx_call(atpx->handle,
422					ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
423					&params);
424		if (!info)
425			return -EIO;
426		kfree(info);
427	}
428	return 0;
429}
430
431/**
432 * amdgpu_atpx_switchto - switch to the requested GPU
433 *
434 * @id: GPU to switch to
435 *
436 * Execute the necessary ATPX functions to switch between the discrete GPU and
437 * integrated GPU (all asics).
438 * Returns 0 on success, error on failure.
439 */
440static int amdgpu_atpx_switchto(enum vga_switcheroo_client_id id)
441{
442	u16 gpu_id;
443
444	if (id == VGA_SWITCHEROO_IGD)
445		gpu_id = ATPX_INTEGRATED_GPU;
446	else
447		gpu_id = ATPX_DISCRETE_GPU;
448
449	amdgpu_atpx_switch_start(&amdgpu_atpx_priv.atpx, gpu_id);
450	amdgpu_atpx_switch_disp_mux(&amdgpu_atpx_priv.atpx, gpu_id);
451	amdgpu_atpx_switch_i2c_mux(&amdgpu_atpx_priv.atpx, gpu_id);
452	amdgpu_atpx_switch_end(&amdgpu_atpx_priv.atpx, gpu_id);
453
454	return 0;
455}
456
457/**
458 * amdgpu_atpx_power_state - power down/up the requested GPU
459 *
460 * @id: GPU to power down/up
461 * @state: requested power state (0 = off, 1 = on)
462 *
463 * Execute the necessary ATPX function to power down/up the discrete GPU
464 * (all asics).
465 * Returns 0 on success, error on failure.
466 */
467static int amdgpu_atpx_power_state(enum vga_switcheroo_client_id id,
468				   enum vga_switcheroo_state state)
469{
470	/* on w500 ACPI can't change intel gpu state */
471	if (id == VGA_SWITCHEROO_IGD)
472		return 0;
473
474	amdgpu_atpx_set_discrete_state(&amdgpu_atpx_priv.atpx, state);
475	return 0;
476}
477
478/**
479 * amdgpu_atpx_pci_probe_handle - look up the ATPX handle
480 *
481 * @pdev: pci device
482 *
483 * Look up the ATPX handles (all asics).
484 * Returns true if the handles are found, false if not.
485 */
486static bool amdgpu_atpx_pci_probe_handle(struct pci_dev *pdev)
487{
488	acpi_handle dhandle, atpx_handle;
489	acpi_status status;
490
491	dhandle = ACPI_HANDLE(&pdev->dev);
492	if (!dhandle)
493		return false;
494
495	status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
496	if (ACPI_FAILURE(status)) {
497		amdgpu_atpx_priv.other_handle = dhandle;
498		return false;
499	}
500	amdgpu_atpx_priv.dhandle = dhandle;
501	amdgpu_atpx_priv.atpx.handle = atpx_handle;
502	return true;
503}
504
505/**
506 * amdgpu_atpx_init - verify the ATPX interface
507 *
508 * Verify the ATPX interface (all asics).
509 * Returns 0 on success, error on failure.
510 */
511static int amdgpu_atpx_init(void)
512{
513	int r;
514
515	/* set up the ATPX handle */
516	r = amdgpu_atpx_verify_interface(&amdgpu_atpx_priv.atpx);
517	if (r)
518		return r;
519
520	/* validate the atpx setup */
521	r = amdgpu_atpx_validate(&amdgpu_atpx_priv.atpx);
522	if (r)
523		return r;
524
525	return 0;
526}
527
528/**
529 * amdgpu_atpx_get_client_id - get the client id
530 *
531 * @pdev: pci device
532 *
533 * look up whether we are the integrated or discrete GPU (all asics).
534 * Returns the client id.
535 */
536static int amdgpu_atpx_get_client_id(struct pci_dev *pdev)
537{
538	if (amdgpu_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
539		return VGA_SWITCHEROO_IGD;
540	else
541		return VGA_SWITCHEROO_DIS;
542}
543
544static const struct vga_switcheroo_handler amdgpu_atpx_handler = {
545	.switchto = amdgpu_atpx_switchto,
546	.power_state = amdgpu_atpx_power_state,
547	.get_client_id = amdgpu_atpx_get_client_id,
548};
549
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
550/**
551 * amdgpu_atpx_detect - detect whether we have PX
552 *
553 * Check if we have a PX system (all asics).
554 * Returns true if we have a PX system, false if not.
555 */
556static bool amdgpu_atpx_detect(void)
557{
558	char acpi_method_name[255] = { 0 };
559	struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
560	struct pci_dev *pdev = NULL;
561	bool has_atpx = false;
562	int vga_count = 0;
563	bool d3_supported = false;
564	struct pci_dev *parent_pdev;
565
566	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
567		vga_count++;
568
569		has_atpx |= (amdgpu_atpx_pci_probe_handle(pdev) == true);
570
571		parent_pdev = pci_upstream_bridge(pdev);
572		d3_supported |= parent_pdev && parent_pdev->bridge_d3;
 
573	}
574
575	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
576		vga_count++;
577
578		has_atpx |= (amdgpu_atpx_pci_probe_handle(pdev) == true);
579
580		parent_pdev = pci_upstream_bridge(pdev);
581		d3_supported |= parent_pdev && parent_pdev->bridge_d3;
 
582	}
583
584	if (has_atpx && vga_count == 2) {
585		acpi_get_name(amdgpu_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
586		printk(KERN_INFO "vga_switcheroo: detected switching method %s handle\n",
587		       acpi_method_name);
588		amdgpu_atpx_priv.atpx_detected = true;
589		amdgpu_atpx_priv.bridge_pm_usable = d3_supported;
590		amdgpu_atpx_init();
591		return true;
592	}
593	return false;
594}
595
596/**
597 * amdgpu_register_atpx_handler - register with vga_switcheroo
598 *
599 * Register the PX callbacks with vga_switcheroo (all asics).
600 */
601void amdgpu_register_atpx_handler(void)
602{
603	bool r;
604	enum vga_switcheroo_handler_flags_t handler_flags = 0;
605
606	/* detect if we have any ATPX + 2 VGA in the system */
607	r = amdgpu_atpx_detect();
608	if (!r)
609		return;
610
611	vga_switcheroo_register_handler(&amdgpu_atpx_handler, handler_flags);
612}
613
614/**
615 * amdgpu_unregister_atpx_handler - unregister with vga_switcheroo
616 *
617 * Unregister the PX callbacks with vga_switcheroo (all asics).
618 */
619void amdgpu_unregister_atpx_handler(void)
620{
621	vga_switcheroo_unregister_handler();
622}