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 
46 static 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 
54 bool nouveau_is_optimus(void) {
55 	return nouveau_dsm_priv.optimus_detected;
56 }
57 
58 bool nouveau_is_v1_dsm(void) {
59 	return nouveau_dsm_priv.dsm_detected;
60 }
61 
62 #ifdef CONFIG_VGA_SWITCHEROO
63 static const guid_t nouveau_dsm_muid =
64 	GUID_INIT(0x9D95A0A0, 0x0060, 0x4D48,
65 		  0xB3, 0x4D, 0x7E, 0x5F, 0xEA, 0x12, 0x9F, 0xD4);
66 
67 static const guid_t nouveau_op_dsm_muid =
68 	GUID_INIT(0xA486D8F8, 0x0BDA, 0x471B,
69 		  0xA7, 0x2B, 0x60, 0x42, 0xA6, 0xB5, 0xBE, 0xE0);
70 
71 static 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  */
110 static 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 
130 static 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 
153 static 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 
160 static 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 
171 static 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 
181 static 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 
195 static 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 
208 static 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 
214 static 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 	*has_pr3 = false;
224 	parent_pdev = pci_upstream_bridge(pdev);
225 	if (parent_pdev) {
226 		if (parent_pdev->bridge_d3)
227 			*has_pr3 = pci_pr3_present(parent_pdev);
228 		else
229 			pci_d3cold_disable(pdev);
230 	}
231 
232 	dhandle = ACPI_HANDLE(&pdev->dev);
233 	if (!dhandle)
234 		return;
235 
236 	if (!acpi_has_method(dhandle, "_DSM"))
237 		return;
238 
239 	supports_mux = acpi_check_dsm(dhandle, &nouveau_dsm_muid, 0x00000102,
240 				      1 << NOUVEAU_DSM_POWER);
241 	optimus_funcs = nouveau_dsm_get_optimus_functions(dhandle);
242 
243 	/* Does not look like a Nvidia device. */
244 	if (!supports_mux && !optimus_funcs)
245 		return;
246 
247 	*dhandle_out = dhandle;
248 	*has_mux = supports_mux;
249 	*has_opt = !!optimus_funcs;
250 	*has_opt_flags = optimus_funcs & (1 << NOUVEAU_DSM_OPTIMUS_FLAGS);
251 
252 	if (optimus_funcs) {
253 		uint32_t result;
254 		nouveau_optimus_dsm(dhandle, NOUVEAU_DSM_OPTIMUS_CAPS, 0,
255 				    &result);
256 		dev_info(&pdev->dev, "optimus capabilities: %s, status %s%s\n",
257 			 (result & OPTIMUS_ENABLED) ? "enabled" : "disabled",
258 			 (result & OPTIMUS_DYNAMIC_PWR_CAP) ? "dynamic power, " : "",
259 			 (result & OPTIMUS_HDA_CODEC_MASK) ? "hda bios codec supported" : "");
260 	}
261 }
262 
263 static bool nouveau_dsm_detect(void)
264 {
265 	char acpi_method_name[255] = { 0 };
266 	struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
267 	struct pci_dev *pdev = NULL;
268 	acpi_handle dhandle = NULL;
269 	bool has_mux = false;
270 	bool has_optimus = false;
271 	bool has_optimus_flags = false;
272 	bool has_power_resources = false;
273 	int vga_count = 0;
274 	bool guid_valid;
275 	bool ret = false;
276 
277 	/* lookup the MXM GUID */
278 	guid_valid = mxm_wmi_supported();
279 
280 	if (guid_valid)
281 		printk("MXM: GUID detected in BIOS\n");
282 
283 	/* now do DSM detection */
284 	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
285 		vga_count++;
286 
287 		nouveau_dsm_pci_probe(pdev, &dhandle, &has_mux, &has_optimus,
288 				      &has_optimus_flags, &has_power_resources);
289 	}
290 
291 	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_3D << 8, pdev)) != NULL) {
292 		vga_count++;
293 
294 		nouveau_dsm_pci_probe(pdev, &dhandle, &has_mux, &has_optimus,
295 				      &has_optimus_flags, &has_power_resources);
296 	}
297 
298 	/* find the optimus DSM or the old v1 DSM */
299 	if (has_optimus) {
300 		nouveau_dsm_priv.dhandle = dhandle;
301 		acpi_get_name(nouveau_dsm_priv.dhandle, ACPI_FULL_PATHNAME,
302 			&buffer);
303 		pr_info("VGA switcheroo: detected Optimus DSM method %s handle\n",
304 			acpi_method_name);
305 		if (has_power_resources)
306 			pr_info("nouveau: detected PR support, will not use DSM\n");
307 		nouveau_dsm_priv.optimus_detected = true;
308 		nouveau_dsm_priv.optimus_flags_detected = has_optimus_flags;
309 		nouveau_dsm_priv.optimus_skip_dsm = has_power_resources;
310 		ret = true;
311 	} else if (vga_count == 2 && has_mux && guid_valid) {
312 		nouveau_dsm_priv.dhandle = dhandle;
313 		acpi_get_name(nouveau_dsm_priv.dhandle, ACPI_FULL_PATHNAME,
314 			&buffer);
315 		pr_info("VGA switcheroo: detected DSM switching method %s handle\n",
316 			acpi_method_name);
317 		nouveau_dsm_priv.dsm_detected = true;
318 		ret = true;
319 	}
320 
321 
322 	return ret;
323 }
324 
325 void nouveau_register_dsm_handler(void)
326 {
327 	bool r;
328 
329 	r = nouveau_dsm_detect();
330 	if (!r)
331 		return;
332 
333 	vga_switcheroo_register_handler(&nouveau_dsm_handler, 0);
334 }
335 
336 /* Must be called for Optimus models before the card can be turned off */
337 void nouveau_switcheroo_optimus_dsm(void)
338 {
339 	u32 result = 0;
340 	if (!nouveau_dsm_priv.optimus_detected || nouveau_dsm_priv.optimus_skip_dsm)
341 		return;
342 
343 	if (nouveau_dsm_priv.optimus_flags_detected)
344 		nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_FLAGS,
345 				    0x3, &result);
346 
347 	nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_CAPS,
348 		NOUVEAU_DSM_OPTIMUS_SET_POWERDOWN, &result);
349 
350 }
351 
352 void nouveau_unregister_dsm_handler(void)
353 {
354 	if (nouveau_dsm_priv.optimus_detected || nouveau_dsm_priv.dsm_detected)
355 		vga_switcheroo_unregister_handler();
356 }
357 #else
358 void nouveau_register_dsm_handler(void) {}
359 void nouveau_unregister_dsm_handler(void) {}
360 void nouveau_switcheroo_optimus_dsm(void) {}
361 #endif
362 
363 void *
364 nouveau_acpi_edid(struct drm_device *dev, struct drm_connector *connector)
365 {
366 	struct acpi_device *acpidev;
367 	int type, ret;
368 	void *edid;
369 
370 	switch (connector->connector_type) {
371 	case DRM_MODE_CONNECTOR_LVDS:
372 	case DRM_MODE_CONNECTOR_eDP:
373 		type = ACPI_VIDEO_DISPLAY_LCD;
374 		break;
375 	default:
376 		return NULL;
377 	}
378 
379 	acpidev = ACPI_COMPANION(dev->dev);
380 	if (!acpidev)
381 		return NULL;
382 
383 	ret = acpi_video_get_edid(acpidev, type, -1, &edid);
384 	if (ret < 0)
385 		return NULL;
386 
387 	return kmemdup(edid, EDID_LENGTH, GFP_KERNEL);
388 }
389