1// SPDX-License-Identifier: MIT
2#include <linux/pci.h>
3#include <linux/acpi.h>
4#include <linux/slab.h>
5#include <linux/mxm-wmi.h>
6#include <linux/vga_switcheroo.h>
7#include <drm/drm_edid.h>
8#include <acpi/video.h>
9
10#include "nouveau_drv.h"
11#include "nouveau_acpi.h"
12
13#define NOUVEAU_DSM_LED 0x02
14#define NOUVEAU_DSM_LED_STATE 0x00
15#define NOUVEAU_DSM_LED_OFF 0x10
16#define NOUVEAU_DSM_LED_STAMINA 0x11
17#define NOUVEAU_DSM_LED_SPEED 0x12
18
19#define NOUVEAU_DSM_POWER 0x03
20#define NOUVEAU_DSM_POWER_STATE 0x00
21#define NOUVEAU_DSM_POWER_SPEED 0x01
22#define NOUVEAU_DSM_POWER_STAMINA 0x02
23
24#define NOUVEAU_DSM_OPTIMUS_CAPS 0x1A
25#define NOUVEAU_DSM_OPTIMUS_FLAGS 0x1B
26
27#define NOUVEAU_DSM_OPTIMUS_POWERDOWN_PS3 (3 << 24)
28#define NOUVEAU_DSM_OPTIMUS_NO_POWERDOWN_PS3 (2 << 24)
29#define NOUVEAU_DSM_OPTIMUS_FLAGS_CHANGED (1)
30
31#define NOUVEAU_DSM_OPTIMUS_SET_POWERDOWN (NOUVEAU_DSM_OPTIMUS_POWERDOWN_PS3 | NOUVEAU_DSM_OPTIMUS_FLAGS_CHANGED)
32
33/* result of the optimus caps function */
34#define OPTIMUS_ENABLED (1 << 0)
35#define OPTIMUS_STATUS_MASK (3 << 3)
36#define OPTIMUS_STATUS_OFF  (0 << 3)
37#define OPTIMUS_STATUS_ON_ENABLED  (1 << 3)
38#define OPTIMUS_STATUS_PWR_STABLE  (3 << 3)
39#define OPTIMUS_DISPLAY_HOTPLUG (1 << 6)
40#define OPTIMUS_CAPS_MASK (7 << 24)
41#define OPTIMUS_DYNAMIC_PWR_CAP (1 << 24)
42
43#define OPTIMUS_AUDIO_CAPS_MASK (3 << 27)
44#define OPTIMUS_HDA_CODEC_MASK (2 << 27) /* hda bios control */
45
46static struct nouveau_dsm_priv {
47	bool dsm_detected;
48	bool optimus_detected;
49	bool optimus_flags_detected;
50	bool optimus_skip_dsm;
51	acpi_handle dhandle;
52} nouveau_dsm_priv;
53
54bool nouveau_is_optimus(void) {
55	return nouveau_dsm_priv.optimus_detected;
56}
57
58bool nouveau_is_v1_dsm(void) {
59	return nouveau_dsm_priv.dsm_detected;
60}
61
62#ifdef CONFIG_VGA_SWITCHEROO
63static const guid_t nouveau_dsm_muid =
64	GUID_INIT(0x9D95A0A0, 0x0060, 0x4D48,
65		  0xB3, 0x4D, 0x7E, 0x5F, 0xEA, 0x12, 0x9F, 0xD4);
66
67static const guid_t nouveau_op_dsm_muid =
68	GUID_INIT(0xA486D8F8, 0x0BDA, 0x471B,
69		  0xA7, 0x2B, 0x60, 0x42, 0xA6, 0xB5, 0xBE, 0xE0);
70
71static int nouveau_optimus_dsm(acpi_handle handle, int func, int arg, uint32_t *result)
72{
73	int i;
74	union acpi_object *obj;
75	char args_buff[4];
76	union acpi_object argv4 = {
77		.buffer.type = ACPI_TYPE_BUFFER,
78		.buffer.length = 4,
79		.buffer.pointer = args_buff
80	};
81
82	/* ACPI is little endian, AABBCCDD becomes {DD,CC,BB,AA} */
83	for (i = 0; i < 4; i++)
84		args_buff[i] = (arg >> i * 8) & 0xFF;
85
86	*result = 0;
87	obj = acpi_evaluate_dsm_typed(handle, &nouveau_op_dsm_muid, 0x00000100,
88				      func, &argv4, ACPI_TYPE_BUFFER);
89	if (!obj) {
90		acpi_handle_info(handle, "failed to evaluate _DSM\n");
91		return AE_ERROR;
92	} else {
93		if (obj->buffer.length == 4) {
94			*result |= obj->buffer.pointer[0];
95			*result |= (obj->buffer.pointer[1] << 8);
96			*result |= (obj->buffer.pointer[2] << 16);
97			*result |= (obj->buffer.pointer[3] << 24);
98		}
99		ACPI_FREE(obj);
100	}
101
102	return 0;
103}
104
105/*
106 * On some platforms, _DSM(nouveau_op_dsm_muid, func0) has special
107 * requirements on the fourth parameter, so a private implementation
108 * instead of using acpi_check_dsm().
109 */
110static int nouveau_dsm_get_optimus_functions(acpi_handle handle)
111{
112	int result;
113
114	/*
115	 * Function 0 returns a Buffer containing available functions.
116	 * The args parameter is ignored for function 0, so just put 0 in it
117	 */
118	if (nouveau_optimus_dsm(handle, 0, 0, &result))
119		return 0;
120
121	/*
122	 * ACPI Spec v4 9.14.1: if bit 0 is zero, no function is supported.
123	 * If the n-th bit is enabled, function n is supported
124	 */
125	if (result & 1 && result & (1 << NOUVEAU_DSM_OPTIMUS_CAPS))
126		return result;
127	return 0;
128}
129
130static int nouveau_dsm(acpi_handle handle, int func, int arg)
131{
132	int ret = 0;
133	union acpi_object *obj;
134	union acpi_object argv4 = {
135		.integer.type = ACPI_TYPE_INTEGER,
136		.integer.value = arg,
137	};
138
139	obj = acpi_evaluate_dsm_typed(handle, &nouveau_dsm_muid, 0x00000102,
140				      func, &argv4, ACPI_TYPE_INTEGER);
141	if (!obj) {
142		acpi_handle_info(handle, "failed to evaluate _DSM\n");
143		return AE_ERROR;
144	} else {
145		if (obj->integer.value == 0x80000002)
146			ret = -ENODEV;
147		ACPI_FREE(obj);
148	}
149
150	return ret;
151}
152
153static int nouveau_dsm_switch_mux(acpi_handle handle, int mux_id)
154{
155	mxm_wmi_call_mxmx(mux_id == NOUVEAU_DSM_LED_STAMINA ? MXM_MXDS_ADAPTER_IGD : MXM_MXDS_ADAPTER_0);
156	mxm_wmi_call_mxds(mux_id == NOUVEAU_DSM_LED_STAMINA ? MXM_MXDS_ADAPTER_IGD : MXM_MXDS_ADAPTER_0);
157	return nouveau_dsm(handle, NOUVEAU_DSM_LED, mux_id);
158}
159
160static int nouveau_dsm_set_discrete_state(acpi_handle handle, enum vga_switcheroo_state state)
161{
162	int arg;
163	if (state == VGA_SWITCHEROO_ON)
164		arg = NOUVEAU_DSM_POWER_SPEED;
165	else
166		arg = NOUVEAU_DSM_POWER_STAMINA;
167	nouveau_dsm(handle, NOUVEAU_DSM_POWER, arg);
168	return 0;
169}
170
171static int nouveau_dsm_switchto(enum vga_switcheroo_client_id id)
172{
173	if (!nouveau_dsm_priv.dsm_detected)
174		return 0;
175	if (id == VGA_SWITCHEROO_IGD)
176		return nouveau_dsm_switch_mux(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_LED_STAMINA);
177	else
178		return nouveau_dsm_switch_mux(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_LED_SPEED);
179}
180
181static int nouveau_dsm_power_state(enum vga_switcheroo_client_id id,
182				   enum vga_switcheroo_state state)
183{
184	if (id == VGA_SWITCHEROO_IGD)
185		return 0;
186
187	/* Optimus laptops have the card already disabled in
188	 * nouveau_switcheroo_set_state */
189	if (!nouveau_dsm_priv.dsm_detected)
190		return 0;
191
192	return nouveau_dsm_set_discrete_state(nouveau_dsm_priv.dhandle, state);
193}
194
195static enum vga_switcheroo_client_id nouveau_dsm_get_client_id(struct pci_dev *pdev)
196{
197	/* easy option one - intel vendor ID means Integrated */
198	if (pdev->vendor == PCI_VENDOR_ID_INTEL)
199		return VGA_SWITCHEROO_IGD;
200
201	/* is this device on Bus 0? - this may need improving */
202	if (pdev->bus->number == 0)
203		return VGA_SWITCHEROO_IGD;
204
205	return VGA_SWITCHEROO_DIS;
206}
207
208static const struct vga_switcheroo_handler nouveau_dsm_handler = {
209	.switchto = nouveau_dsm_switchto,
210	.power_state = nouveau_dsm_power_state,
211	.get_client_id = nouveau_dsm_get_client_id,
212};
213
214static void nouveau_dsm_pci_probe(struct pci_dev *pdev, acpi_handle *dhandle_out,
215				  bool *has_mux, bool *has_opt,
216				  bool *has_opt_flags, bool *has_pr3)
217{
218	acpi_handle dhandle;
219	bool supports_mux;
220	int optimus_funcs;
221	struct pci_dev *parent_pdev;
222
223	if (pdev->vendor != PCI_VENDOR_ID_NVIDIA)
224		return;
225
226	*has_pr3 = false;
227	parent_pdev = pci_upstream_bridge(pdev);
228	if (parent_pdev) {
229		if (parent_pdev->bridge_d3)
230			*has_pr3 = pci_pr3_present(parent_pdev);
231		else
232			pci_d3cold_disable(pdev);
233	}
234
235	dhandle = ACPI_HANDLE(&pdev->dev);
236	if (!dhandle)
237		return;
238
239	if (!acpi_has_method(dhandle, "_DSM"))
240		return;
241
242	supports_mux = acpi_check_dsm(dhandle, &nouveau_dsm_muid, 0x00000102,
243				      1 << NOUVEAU_DSM_POWER);
244	optimus_funcs = nouveau_dsm_get_optimus_functions(dhandle);
245
246	/* Does not look like a Nvidia device. */
247	if (!supports_mux && !optimus_funcs)
248		return;
249
250	*dhandle_out = dhandle;
251	*has_mux = supports_mux;
252	*has_opt = !!optimus_funcs;
253	*has_opt_flags = optimus_funcs & (1 << NOUVEAU_DSM_OPTIMUS_FLAGS);
254
255	if (optimus_funcs) {
256		uint32_t result;
257		nouveau_optimus_dsm(dhandle, NOUVEAU_DSM_OPTIMUS_CAPS, 0,
258				    &result);
259		dev_info(&pdev->dev, "optimus capabilities: %s, status %s%s\n",
260			 (result & OPTIMUS_ENABLED) ? "enabled" : "disabled",
261			 (result & OPTIMUS_DYNAMIC_PWR_CAP) ? "dynamic power, " : "",
262			 (result & OPTIMUS_HDA_CODEC_MASK) ? "hda bios codec supported" : "");
263	}
264}
265
266static bool nouveau_dsm_detect(void)
267{
268	char acpi_method_name[255] = { 0 };
269	struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
270	struct pci_dev *pdev = NULL;
271	acpi_handle dhandle = NULL;
272	bool has_mux = false;
273	bool has_optimus = false;
274	bool has_optimus_flags = false;
275	bool has_power_resources = false;
276	int vga_count = 0;
277	bool guid_valid;
278	bool ret = false;
279
280	/* lookup the MXM GUID */
281	guid_valid = mxm_wmi_supported();
282
283	if (guid_valid)
284		printk("MXM: GUID detected in BIOS\n");
285
286	/* now do DSM detection */
287	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
288		vga_count++;
289
290		nouveau_dsm_pci_probe(pdev, &dhandle, &has_mux, &has_optimus,
291				      &has_optimus_flags, &has_power_resources);
292	}
293
294	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_3D << 8, pdev)) != NULL) {
295		vga_count++;
296
297		nouveau_dsm_pci_probe(pdev, &dhandle, &has_mux, &has_optimus,
298				      &has_optimus_flags, &has_power_resources);
299	}
300
301	/* find the optimus DSM or the old v1 DSM */
302	if (has_optimus) {
303		nouveau_dsm_priv.dhandle = dhandle;
304		acpi_get_name(nouveau_dsm_priv.dhandle, ACPI_FULL_PATHNAME,
305			&buffer);
306		pr_info("VGA switcheroo: detected Optimus DSM method %s handle\n",
307			acpi_method_name);
308		if (has_power_resources)
309			pr_info("nouveau: detected PR support, will not use DSM\n");
310		nouveau_dsm_priv.optimus_detected = true;
311		nouveau_dsm_priv.optimus_flags_detected = has_optimus_flags;
312		nouveau_dsm_priv.optimus_skip_dsm = has_power_resources;
313		ret = true;
314	} else if (vga_count == 2 && has_mux && guid_valid) {
315		nouveau_dsm_priv.dhandle = dhandle;
316		acpi_get_name(nouveau_dsm_priv.dhandle, ACPI_FULL_PATHNAME,
317			&buffer);
318		pr_info("VGA switcheroo: detected DSM switching method %s handle\n",
319			acpi_method_name);
320		nouveau_dsm_priv.dsm_detected = true;
321		ret = true;
322	}
323
324
325	return ret;
326}
327
328void nouveau_register_dsm_handler(void)
329{
330	bool r;
331
332	r = nouveau_dsm_detect();
333	if (!r)
334		return;
335
336	vga_switcheroo_register_handler(&nouveau_dsm_handler, 0);
337}
338
339/* Must be called for Optimus models before the card can be turned off */
340void nouveau_switcheroo_optimus_dsm(void)
341{
342	u32 result = 0;
343	if (!nouveau_dsm_priv.optimus_detected || nouveau_dsm_priv.optimus_skip_dsm)
344		return;
345
346	if (nouveau_dsm_priv.optimus_flags_detected)
347		nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_FLAGS,
348				    0x3, &result);
349
350	nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_CAPS,
351		NOUVEAU_DSM_OPTIMUS_SET_POWERDOWN, &result);
352
353}
354
355void nouveau_unregister_dsm_handler(void)
356{
357	if (nouveau_dsm_priv.optimus_detected || nouveau_dsm_priv.dsm_detected)
358		vga_switcheroo_unregister_handler();
359}
360#else
361void nouveau_register_dsm_handler(void) {}
362void nouveau_unregister_dsm_handler(void) {}
363void nouveau_switcheroo_optimus_dsm(void) {}
364#endif
365
366void *
367nouveau_acpi_edid(struct drm_device *dev, struct drm_connector *connector)
368{
369	struct acpi_device *acpidev;
370	int type, ret;
371	void *edid;
372
373	switch (connector->connector_type) {
374	case DRM_MODE_CONNECTOR_LVDS:
375	case DRM_MODE_CONNECTOR_eDP:
376		type = ACPI_VIDEO_DISPLAY_LCD;
377		break;
378	default:
379		return NULL;
380	}
381
382	acpidev = ACPI_COMPANION(dev->dev);
383	if (!acpidev)
384		return NULL;
385
386	ret = acpi_video_get_edid(acpidev, type, -1, &edid);
387	if (ret < 0)
388		return NULL;
389
390	return kmemdup(edid, EDID_LENGTH, GFP_KERNEL);
391}
392
393bool nouveau_acpi_video_backlight_use_native(void)
394{
395	return acpi_video_backlight_use_native();
396}
397
398void nouveau_acpi_video_register_backlight(void)
399{
400	acpi_video_register_backlight();
401}
402