1 #include <linux/pci.h>
2 #include <linux/acpi.h>
3 #include <linux/slab.h>
4 #include <acpi/acpi_drivers.h>
5 #include <acpi/acpi_bus.h>
6 #include <acpi/video.h>
7 #include <acpi/acpi.h>
8 #include <linux/mxm-wmi.h>
9 
10 #include <linux/vga_switcheroo.h>
11 
12 #include <drm/drm_edid.h>
13 
14 #include "nouveau_drm.h"
15 #include "nouveau_acpi.h"
16 
17 #define NOUVEAU_DSM_LED 0x02
18 #define NOUVEAU_DSM_LED_STATE 0x00
19 #define NOUVEAU_DSM_LED_OFF 0x10
20 #define NOUVEAU_DSM_LED_STAMINA 0x11
21 #define NOUVEAU_DSM_LED_SPEED 0x12
22 
23 #define NOUVEAU_DSM_POWER 0x03
24 #define NOUVEAU_DSM_POWER_STATE 0x00
25 #define NOUVEAU_DSM_POWER_SPEED 0x01
26 #define NOUVEAU_DSM_POWER_STAMINA 0x02
27 
28 #define NOUVEAU_DSM_OPTIMUS_FN 0x1A
29 #define NOUVEAU_DSM_OPTIMUS_ARGS 0x03000001
30 
31 static struct nouveau_dsm_priv {
32 	bool dsm_detected;
33 	bool optimus_detected;
34 	acpi_handle dhandle;
35 	acpi_handle rom_handle;
36 } nouveau_dsm_priv;
37 
38 bool nouveau_is_optimus(void) {
39 	return nouveau_dsm_priv.optimus_detected;
40 }
41 
42 bool nouveau_is_v1_dsm(void) {
43 	return nouveau_dsm_priv.dsm_detected;
44 }
45 
46 #define NOUVEAU_DSM_HAS_MUX 0x1
47 #define NOUVEAU_DSM_HAS_OPT 0x2
48 
49 static const char nouveau_dsm_muid[] = {
50 	0xA0, 0xA0, 0x95, 0x9D, 0x60, 0x00, 0x48, 0x4D,
51 	0xB3, 0x4D, 0x7E, 0x5F, 0xEA, 0x12, 0x9F, 0xD4,
52 };
53 
54 static const char nouveau_op_dsm_muid[] = {
55 	0xF8, 0xD8, 0x86, 0xA4, 0xDA, 0x0B, 0x1B, 0x47,
56 	0xA7, 0x2B, 0x60, 0x42, 0xA6, 0xB5, 0xBE, 0xE0,
57 };
58 
59 static int nouveau_optimus_dsm(acpi_handle handle, int func, int arg, uint32_t *result)
60 {
61 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
62 	struct acpi_object_list input;
63 	union acpi_object params[4];
64 	union acpi_object *obj;
65 	int i, err;
66 	char args_buff[4];
67 
68 	input.count = 4;
69 	input.pointer = params;
70 	params[0].type = ACPI_TYPE_BUFFER;
71 	params[0].buffer.length = sizeof(nouveau_op_dsm_muid);
72 	params[0].buffer.pointer = (char *)nouveau_op_dsm_muid;
73 	params[1].type = ACPI_TYPE_INTEGER;
74 	params[1].integer.value = 0x00000100;
75 	params[2].type = ACPI_TYPE_INTEGER;
76 	params[2].integer.value = func;
77 	params[3].type = ACPI_TYPE_BUFFER;
78 	params[3].buffer.length = 4;
79 	/* ACPI is little endian, AABBCCDD becomes {DD,CC,BB,AA} */
80 	for (i = 0; i < 4; i++)
81 		args_buff[i] = (arg >> i * 8) & 0xFF;
82 	params[3].buffer.pointer = args_buff;
83 
84 	err = acpi_evaluate_object(handle, "_DSM", &input, &output);
85 	if (err) {
86 		printk(KERN_INFO "failed to evaluate _DSM: %d\n", err);
87 		return err;
88 	}
89 
90 	obj = (union acpi_object *)output.pointer;
91 
92 	if (obj->type == ACPI_TYPE_INTEGER)
93 		if (obj->integer.value == 0x80000002) {
94 			return -ENODEV;
95 		}
96 
97 	if (obj->type == ACPI_TYPE_BUFFER) {
98 		if (obj->buffer.length == 4 && result) {
99 			*result = 0;
100 			*result |= obj->buffer.pointer[0];
101 			*result |= (obj->buffer.pointer[1] << 8);
102 			*result |= (obj->buffer.pointer[2] << 16);
103 			*result |= (obj->buffer.pointer[3] << 24);
104 		}
105 	}
106 
107 	kfree(output.pointer);
108 	return 0;
109 }
110 
111 static int nouveau_dsm(acpi_handle handle, int func, int arg, uint32_t *result)
112 {
113 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
114 	struct acpi_object_list input;
115 	union acpi_object params[4];
116 	union acpi_object *obj;
117 	int err;
118 
119 	input.count = 4;
120 	input.pointer = params;
121 	params[0].type = ACPI_TYPE_BUFFER;
122 	params[0].buffer.length = sizeof(nouveau_dsm_muid);
123 	params[0].buffer.pointer = (char *)nouveau_dsm_muid;
124 	params[1].type = ACPI_TYPE_INTEGER;
125 	params[1].integer.value = 0x00000102;
126 	params[2].type = ACPI_TYPE_INTEGER;
127 	params[2].integer.value = func;
128 	params[3].type = ACPI_TYPE_INTEGER;
129 	params[3].integer.value = arg;
130 
131 	err = acpi_evaluate_object(handle, "_DSM", &input, &output);
132 	if (err) {
133 		printk(KERN_INFO "failed to evaluate _DSM: %d\n", err);
134 		return err;
135 	}
136 
137 	obj = (union acpi_object *)output.pointer;
138 
139 	if (obj->type == ACPI_TYPE_INTEGER)
140 		if (obj->integer.value == 0x80000002)
141 			return -ENODEV;
142 
143 	if (obj->type == ACPI_TYPE_BUFFER) {
144 		if (obj->buffer.length == 4 && result) {
145 			*result = 0;
146 			*result |= obj->buffer.pointer[0];
147 			*result |= (obj->buffer.pointer[1] << 8);
148 			*result |= (obj->buffer.pointer[2] << 16);
149 			*result |= (obj->buffer.pointer[3] << 24);
150 		}
151 	}
152 
153 	kfree(output.pointer);
154 	return 0;
155 }
156 
157 /* Returns 1 if a DSM function is usable and 0 otherwise */
158 static int nouveau_test_dsm(acpi_handle test_handle,
159 	int (*dsm_func)(acpi_handle, int, int, uint32_t *),
160 	int sfnc)
161 {
162 	u32 result = 0;
163 
164 	/* Function 0 returns a Buffer containing available functions. The args
165 	 * parameter is ignored for function 0, so just put 0 in it */
166 	if (dsm_func(test_handle, 0, 0, &result))
167 		return 0;
168 
169 	/* ACPI Spec v4 9.14.1: if bit 0 is zero, no function is supported. If
170 	 * the n-th bit is enabled, function n is supported */
171 	return result & 1 && result & (1 << sfnc);
172 }
173 
174 static int nouveau_dsm_switch_mux(acpi_handle handle, int mux_id)
175 {
176 	mxm_wmi_call_mxmx(mux_id == NOUVEAU_DSM_LED_STAMINA ? MXM_MXDS_ADAPTER_IGD : MXM_MXDS_ADAPTER_0);
177 	mxm_wmi_call_mxds(mux_id == NOUVEAU_DSM_LED_STAMINA ? MXM_MXDS_ADAPTER_IGD : MXM_MXDS_ADAPTER_0);
178 	return nouveau_dsm(handle, NOUVEAU_DSM_LED, mux_id, NULL);
179 }
180 
181 static int nouveau_dsm_set_discrete_state(acpi_handle handle, enum vga_switcheroo_state state)
182 {
183 	int arg;
184 	if (state == VGA_SWITCHEROO_ON)
185 		arg = NOUVEAU_DSM_POWER_SPEED;
186 	else
187 		arg = NOUVEAU_DSM_POWER_STAMINA;
188 	nouveau_dsm(handle, NOUVEAU_DSM_POWER, arg, NULL);
189 	return 0;
190 }
191 
192 static int nouveau_dsm_switchto(enum vga_switcheroo_client_id id)
193 {
194 	if (!nouveau_dsm_priv.dsm_detected)
195 		return 0;
196 	if (id == VGA_SWITCHEROO_IGD)
197 		return nouveau_dsm_switch_mux(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_LED_STAMINA);
198 	else
199 		return nouveau_dsm_switch_mux(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_LED_SPEED);
200 }
201 
202 static int nouveau_dsm_power_state(enum vga_switcheroo_client_id id,
203 				   enum vga_switcheroo_state state)
204 {
205 	if (id == VGA_SWITCHEROO_IGD)
206 		return 0;
207 
208 	/* Optimus laptops have the card already disabled in
209 	 * nouveau_switcheroo_set_state */
210 	if (!nouveau_dsm_priv.dsm_detected)
211 		return 0;
212 
213 	return nouveau_dsm_set_discrete_state(nouveau_dsm_priv.dhandle, state);
214 }
215 
216 static int nouveau_dsm_get_client_id(struct pci_dev *pdev)
217 {
218 	/* easy option one - intel vendor ID means Integrated */
219 	if (pdev->vendor == PCI_VENDOR_ID_INTEL)
220 		return VGA_SWITCHEROO_IGD;
221 
222 	/* is this device on Bus 0? - this may need improving */
223 	if (pdev->bus->number == 0)
224 		return VGA_SWITCHEROO_IGD;
225 
226 	return VGA_SWITCHEROO_DIS;
227 }
228 
229 static struct vga_switcheroo_handler nouveau_dsm_handler = {
230 	.switchto = nouveau_dsm_switchto,
231 	.power_state = nouveau_dsm_power_state,
232 	.get_client_id = nouveau_dsm_get_client_id,
233 };
234 
235 static int nouveau_dsm_pci_probe(struct pci_dev *pdev)
236 {
237 	acpi_handle dhandle, nvidia_handle;
238 	acpi_status status;
239 	int retval = 0;
240 
241 	dhandle = DEVICE_ACPI_HANDLE(&pdev->dev);
242 	if (!dhandle)
243 		return false;
244 
245 	status = acpi_get_handle(dhandle, "_DSM", &nvidia_handle);
246 	if (ACPI_FAILURE(status)) {
247 		return false;
248 	}
249 
250 	if (nouveau_test_dsm(dhandle, nouveau_dsm, NOUVEAU_DSM_POWER))
251 		retval |= NOUVEAU_DSM_HAS_MUX;
252 
253 	if (nouveau_test_dsm(dhandle, nouveau_optimus_dsm,
254 		NOUVEAU_DSM_OPTIMUS_FN))
255 		retval |= NOUVEAU_DSM_HAS_OPT;
256 
257 	if (retval)
258 		nouveau_dsm_priv.dhandle = dhandle;
259 
260 	return retval;
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 	int has_dsm = 0;
269 	int has_optimus = 0;
270 	int vga_count = 0;
271 	bool guid_valid;
272 	int retval;
273 	bool ret = false;
274 
275 	/* lookup the MXM GUID */
276 	guid_valid = mxm_wmi_supported();
277 
278 	if (guid_valid)
279 		printk("MXM: GUID detected in BIOS\n");
280 
281 	/* now do DSM detection */
282 	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
283 		vga_count++;
284 
285 		retval = nouveau_dsm_pci_probe(pdev);
286 		if (retval & NOUVEAU_DSM_HAS_MUX)
287 			has_dsm |= 1;
288 		if (retval & NOUVEAU_DSM_HAS_OPT)
289 			has_optimus = 1;
290 	}
291 
292 	/* find the optimus DSM or the old v1 DSM */
293 	if (has_optimus == 1) {
294 		acpi_get_name(nouveau_dsm_priv.dhandle, ACPI_FULL_PATHNAME,
295 			&buffer);
296 		printk(KERN_INFO "VGA switcheroo: detected Optimus DSM method %s handle\n",
297 			acpi_method_name);
298 		nouveau_dsm_priv.optimus_detected = true;
299 		ret = true;
300 	} else if (vga_count == 2 && has_dsm && guid_valid) {
301 		acpi_get_name(nouveau_dsm_priv.dhandle, ACPI_FULL_PATHNAME,
302 			&buffer);
303 		printk(KERN_INFO "VGA switcheroo: detected DSM switching method %s handle\n",
304 			acpi_method_name);
305 		nouveau_dsm_priv.dsm_detected = true;
306 		ret = true;
307 	}
308 
309 
310 	return ret;
311 }
312 
313 void nouveau_register_dsm_handler(void)
314 {
315 	bool r;
316 
317 	r = nouveau_dsm_detect();
318 	if (!r)
319 		return;
320 
321 	vga_switcheroo_register_handler(&nouveau_dsm_handler);
322 }
323 
324 /* Must be called for Optimus models before the card can be turned off */
325 void nouveau_switcheroo_optimus_dsm(void)
326 {
327 	u32 result = 0;
328 	if (!nouveau_dsm_priv.optimus_detected)
329 		return;
330 
331 	nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_FN,
332 		NOUVEAU_DSM_OPTIMUS_ARGS, &result);
333 }
334 
335 void nouveau_unregister_dsm_handler(void)
336 {
337 	if (nouveau_dsm_priv.optimus_detected || nouveau_dsm_priv.dsm_detected)
338 		vga_switcheroo_unregister_handler();
339 }
340 
341 /* retrieve the ROM in 4k blocks */
342 static int nouveau_rom_call(acpi_handle rom_handle, uint8_t *bios,
343 			    int offset, int len)
344 {
345 	acpi_status status;
346 	union acpi_object rom_arg_elements[2], *obj;
347 	struct acpi_object_list rom_arg;
348 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL};
349 
350 	rom_arg.count = 2;
351 	rom_arg.pointer = &rom_arg_elements[0];
352 
353 	rom_arg_elements[0].type = ACPI_TYPE_INTEGER;
354 	rom_arg_elements[0].integer.value = offset;
355 
356 	rom_arg_elements[1].type = ACPI_TYPE_INTEGER;
357 	rom_arg_elements[1].integer.value = len;
358 
359 	status = acpi_evaluate_object(rom_handle, NULL, &rom_arg, &buffer);
360 	if (ACPI_FAILURE(status)) {
361 		printk(KERN_INFO "failed to evaluate ROM got %s\n", acpi_format_exception(status));
362 		return -ENODEV;
363 	}
364 	obj = (union acpi_object *)buffer.pointer;
365 	memcpy(bios+offset, obj->buffer.pointer, len);
366 	kfree(buffer.pointer);
367 	return len;
368 }
369 
370 bool nouveau_acpi_rom_supported(struct pci_dev *pdev)
371 {
372 	acpi_status status;
373 	acpi_handle dhandle, rom_handle;
374 
375 	if (!nouveau_dsm_priv.dsm_detected && !nouveau_dsm_priv.optimus_detected)
376 		return false;
377 
378 	dhandle = DEVICE_ACPI_HANDLE(&pdev->dev);
379 	if (!dhandle)
380 		return false;
381 
382 	status = acpi_get_handle(dhandle, "_ROM", &rom_handle);
383 	if (ACPI_FAILURE(status))
384 		return false;
385 
386 	nouveau_dsm_priv.rom_handle = rom_handle;
387 	return true;
388 }
389 
390 int nouveau_acpi_get_bios_chunk(uint8_t *bios, int offset, int len)
391 {
392 	return nouveau_rom_call(nouveau_dsm_priv.rom_handle, bios, offset, len);
393 }
394 
395 void *
396 nouveau_acpi_edid(struct drm_device *dev, struct drm_connector *connector)
397 {
398 	struct acpi_device *acpidev;
399 	acpi_handle handle;
400 	int type, ret;
401 	void *edid;
402 
403 	switch (connector->connector_type) {
404 	case DRM_MODE_CONNECTOR_LVDS:
405 	case DRM_MODE_CONNECTOR_eDP:
406 		type = ACPI_VIDEO_DISPLAY_LCD;
407 		break;
408 	default:
409 		return NULL;
410 	}
411 
412 	handle = DEVICE_ACPI_HANDLE(&dev->pdev->dev);
413 	if (!handle)
414 		return NULL;
415 
416 	ret = acpi_bus_get_device(handle, &acpidev);
417 	if (ret)
418 		return NULL;
419 
420 	ret = acpi_video_get_edid(acpidev, type, -1, &edid);
421 	if (ret < 0)
422 		return NULL;
423 
424 	return kmemdup(edid, EDID_LENGTH, GFP_KERNEL);
425 }
426