1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Intel ACPI functions
4  *
5  * _DSM related code stolen from nouveau_acpi.c.
6  */
7 
8 #include <linux/pci.h>
9 #include <linux/acpi.h>
10 #include <acpi/video.h>
11 
12 #include "i915_drv.h"
13 #include "intel_acpi.h"
14 #include "intel_display_types.h"
15 
16 #define INTEL_DSM_REVISION_ID 1 /* For Calpella anyway... */
17 #define INTEL_DSM_FN_PLATFORM_MUX_INFO 1 /* No args */
18 
19 static const guid_t intel_dsm_guid =
20 	GUID_INIT(0x7ed873d3, 0xc2d0, 0x4e4f,
21 		  0xa8, 0x54, 0x0f, 0x13, 0x17, 0xb0, 0x1c, 0x2c);
22 
23 #define INTEL_DSM_FN_GET_BIOS_DATA_FUNCS_SUPPORTED 0 /* No args */
24 
25 static const guid_t intel_dsm_guid2 =
26 	GUID_INIT(0x3e5b41c6, 0xeb1d, 0x4260,
27 		  0x9d, 0x15, 0xc7, 0x1f, 0xba, 0xda, 0xe4, 0x14);
28 
29 static char *intel_dsm_port_name(u8 id)
30 {
31 	switch (id) {
32 	case 0:
33 		return "Reserved";
34 	case 1:
35 		return "Analog VGA";
36 	case 2:
37 		return "LVDS";
38 	case 3:
39 		return "Reserved";
40 	case 4:
41 		return "HDMI/DVI_B";
42 	case 5:
43 		return "HDMI/DVI_C";
44 	case 6:
45 		return "HDMI/DVI_D";
46 	case 7:
47 		return "DisplayPort_A";
48 	case 8:
49 		return "DisplayPort_B";
50 	case 9:
51 		return "DisplayPort_C";
52 	case 0xa:
53 		return "DisplayPort_D";
54 	case 0xb:
55 	case 0xc:
56 	case 0xd:
57 		return "Reserved";
58 	case 0xe:
59 		return "WiDi";
60 	default:
61 		return "bad type";
62 	}
63 }
64 
65 static char *intel_dsm_mux_type(u8 type)
66 {
67 	switch (type) {
68 	case 0:
69 		return "unknown";
70 	case 1:
71 		return "No MUX, iGPU only";
72 	case 2:
73 		return "No MUX, dGPU only";
74 	case 3:
75 		return "MUXed between iGPU and dGPU";
76 	default:
77 		return "bad type";
78 	}
79 }
80 
81 static void intel_dsm_platform_mux_info(acpi_handle dhandle)
82 {
83 	int i;
84 	union acpi_object *pkg, *connector_count;
85 
86 	pkg = acpi_evaluate_dsm_typed(dhandle, &intel_dsm_guid,
87 			INTEL_DSM_REVISION_ID, INTEL_DSM_FN_PLATFORM_MUX_INFO,
88 			NULL, ACPI_TYPE_PACKAGE);
89 	if (!pkg) {
90 		DRM_DEBUG_DRIVER("failed to evaluate _DSM\n");
91 		return;
92 	}
93 
94 	if (!pkg->package.count) {
95 		DRM_DEBUG_DRIVER("no connection in _DSM\n");
96 		return;
97 	}
98 
99 	connector_count = &pkg->package.elements[0];
100 	DRM_DEBUG_DRIVER("MUX info connectors: %lld\n",
101 		  (unsigned long long)connector_count->integer.value);
102 	for (i = 1; i < pkg->package.count; i++) {
103 		union acpi_object *obj = &pkg->package.elements[i];
104 		union acpi_object *connector_id;
105 		union acpi_object *info;
106 
107 		if (obj->type != ACPI_TYPE_PACKAGE || obj->package.count < 2) {
108 			DRM_DEBUG_DRIVER("Invalid object for MUX #%d\n", i);
109 			continue;
110 		}
111 
112 		connector_id = &obj->package.elements[0];
113 		info = &obj->package.elements[1];
114 		if (info->type != ACPI_TYPE_BUFFER || info->buffer.length < 4) {
115 			DRM_DEBUG_DRIVER("Invalid info for MUX obj #%d\n", i);
116 			continue;
117 		}
118 
119 		DRM_DEBUG_DRIVER("Connector id: 0x%016llx\n",
120 			  (unsigned long long)connector_id->integer.value);
121 		DRM_DEBUG_DRIVER("  port id: %s\n",
122 		       intel_dsm_port_name(info->buffer.pointer[0]));
123 		DRM_DEBUG_DRIVER("  display mux info: %s\n",
124 		       intel_dsm_mux_type(info->buffer.pointer[1]));
125 		DRM_DEBUG_DRIVER("  aux/dc mux info: %s\n",
126 		       intel_dsm_mux_type(info->buffer.pointer[2]));
127 		DRM_DEBUG_DRIVER("  hpd mux info: %s\n",
128 		       intel_dsm_mux_type(info->buffer.pointer[3]));
129 	}
130 
131 	ACPI_FREE(pkg);
132 }
133 
134 static acpi_handle intel_dsm_pci_probe(struct pci_dev *pdev)
135 {
136 	acpi_handle dhandle;
137 
138 	dhandle = ACPI_HANDLE(&pdev->dev);
139 	if (!dhandle)
140 		return NULL;
141 
142 	if (!acpi_check_dsm(dhandle, &intel_dsm_guid, INTEL_DSM_REVISION_ID,
143 			    1 << INTEL_DSM_FN_PLATFORM_MUX_INFO)) {
144 		DRM_DEBUG_KMS("no _DSM method for intel device\n");
145 		return NULL;
146 	}
147 
148 	intel_dsm_platform_mux_info(dhandle);
149 
150 	return dhandle;
151 }
152 
153 static bool intel_dsm_detect(void)
154 {
155 	acpi_handle dhandle = NULL;
156 	char acpi_method_name[255] = { 0 };
157 	struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
158 	struct pci_dev *pdev = NULL;
159 	int vga_count = 0;
160 
161 	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
162 		vga_count++;
163 		dhandle = intel_dsm_pci_probe(pdev) ?: dhandle;
164 	}
165 
166 	if (vga_count == 2 && dhandle) {
167 		acpi_get_name(dhandle, ACPI_FULL_PATHNAME, &buffer);
168 		DRM_DEBUG_DRIVER("vga_switcheroo: detected DSM switching method %s handle\n",
169 				 acpi_method_name);
170 		return true;
171 	}
172 
173 	return false;
174 }
175 
176 void intel_register_dsm_handler(void)
177 {
178 	if (!intel_dsm_detect())
179 		return;
180 }
181 
182 void intel_unregister_dsm_handler(void)
183 {
184 }
185 
186 void intel_dsm_get_bios_data_funcs_supported(struct drm_i915_private *i915)
187 {
188 	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
189 	acpi_handle dhandle;
190 	union acpi_object *obj;
191 
192 	dhandle = ACPI_HANDLE(&pdev->dev);
193 	if (!dhandle)
194 		return;
195 
196 	obj = acpi_evaluate_dsm(dhandle, &intel_dsm_guid2, INTEL_DSM_REVISION_ID,
197 				INTEL_DSM_FN_GET_BIOS_DATA_FUNCS_SUPPORTED, NULL);
198 	if (obj)
199 		ACPI_FREE(obj);
200 }
201 
202 /*
203  * ACPI Specification, Revision 5.0, Appendix B.3.2 _DOD (Enumerate All Devices
204  * Attached to the Display Adapter).
205  */
206 #define ACPI_DISPLAY_INDEX_SHIFT		0
207 #define ACPI_DISPLAY_INDEX_MASK			(0xf << 0)
208 #define ACPI_DISPLAY_PORT_ATTACHMENT_SHIFT	4
209 #define ACPI_DISPLAY_PORT_ATTACHMENT_MASK	(0xf << 4)
210 #define ACPI_DISPLAY_TYPE_SHIFT			8
211 #define ACPI_DISPLAY_TYPE_MASK			(0xf << 8)
212 #define ACPI_DISPLAY_TYPE_OTHER			(0 << 8)
213 #define ACPI_DISPLAY_TYPE_VGA			(1 << 8)
214 #define ACPI_DISPLAY_TYPE_TV			(2 << 8)
215 #define ACPI_DISPLAY_TYPE_EXTERNAL_DIGITAL	(3 << 8)
216 #define ACPI_DISPLAY_TYPE_INTERNAL_DIGITAL	(4 << 8)
217 #define ACPI_VENDOR_SPECIFIC_SHIFT		12
218 #define ACPI_VENDOR_SPECIFIC_MASK		(0xf << 12)
219 #define ACPI_BIOS_CAN_DETECT			(1 << 16)
220 #define ACPI_DEPENDS_ON_VGA			(1 << 17)
221 #define ACPI_PIPE_ID_SHIFT			18
222 #define ACPI_PIPE_ID_MASK			(7 << 18)
223 #define ACPI_DEVICE_ID_SCHEME			(1ULL << 31)
224 
225 static u32 acpi_display_type(struct intel_connector *connector)
226 {
227 	u32 display_type;
228 
229 	switch (connector->base.connector_type) {
230 	case DRM_MODE_CONNECTOR_VGA:
231 	case DRM_MODE_CONNECTOR_DVIA:
232 		display_type = ACPI_DISPLAY_TYPE_VGA;
233 		break;
234 	case DRM_MODE_CONNECTOR_Composite:
235 	case DRM_MODE_CONNECTOR_SVIDEO:
236 	case DRM_MODE_CONNECTOR_Component:
237 	case DRM_MODE_CONNECTOR_9PinDIN:
238 	case DRM_MODE_CONNECTOR_TV:
239 		display_type = ACPI_DISPLAY_TYPE_TV;
240 		break;
241 	case DRM_MODE_CONNECTOR_DVII:
242 	case DRM_MODE_CONNECTOR_DVID:
243 	case DRM_MODE_CONNECTOR_DisplayPort:
244 	case DRM_MODE_CONNECTOR_HDMIA:
245 	case DRM_MODE_CONNECTOR_HDMIB:
246 		display_type = ACPI_DISPLAY_TYPE_EXTERNAL_DIGITAL;
247 		break;
248 	case DRM_MODE_CONNECTOR_LVDS:
249 	case DRM_MODE_CONNECTOR_eDP:
250 	case DRM_MODE_CONNECTOR_DSI:
251 		display_type = ACPI_DISPLAY_TYPE_INTERNAL_DIGITAL;
252 		break;
253 	case DRM_MODE_CONNECTOR_Unknown:
254 	case DRM_MODE_CONNECTOR_VIRTUAL:
255 		display_type = ACPI_DISPLAY_TYPE_OTHER;
256 		break;
257 	default:
258 		MISSING_CASE(connector->base.connector_type);
259 		display_type = ACPI_DISPLAY_TYPE_OTHER;
260 		break;
261 	}
262 
263 	return display_type;
264 }
265 
266 void intel_acpi_device_id_update(struct drm_i915_private *dev_priv)
267 {
268 	struct drm_device *drm_dev = &dev_priv->drm;
269 	struct intel_connector *connector;
270 	struct drm_connector_list_iter conn_iter;
271 	u8 display_index[16] = {};
272 
273 	/* Populate the ACPI IDs for all connectors for a given drm_device */
274 	drm_connector_list_iter_begin(drm_dev, &conn_iter);
275 	for_each_intel_connector_iter(connector, &conn_iter) {
276 		u32 device_id, type;
277 
278 		device_id = acpi_display_type(connector);
279 
280 		/* Use display type specific display index. */
281 		type = (device_id & ACPI_DISPLAY_TYPE_MASK)
282 			>> ACPI_DISPLAY_TYPE_SHIFT;
283 		device_id |= display_index[type]++ << ACPI_DISPLAY_INDEX_SHIFT;
284 
285 		connector->acpi_device_id = device_id;
286 	}
287 	drm_connector_list_iter_end(&conn_iter);
288 }
289 
290 /* NOTE: The connector order must be final before this is called. */
291 void intel_acpi_assign_connector_fwnodes(struct drm_i915_private *i915)
292 {
293 	struct drm_connector_list_iter conn_iter;
294 	struct drm_device *drm_dev = &i915->drm;
295 	struct fwnode_handle *fwnode = NULL;
296 	struct drm_connector *connector;
297 	struct acpi_device *adev;
298 
299 	drm_connector_list_iter_begin(drm_dev, &conn_iter);
300 	drm_for_each_connector_iter(connector, &conn_iter) {
301 		/* Always getting the next, even when the last was not used. */
302 		fwnode = device_get_next_child_node(drm_dev->dev, fwnode);
303 		if (!fwnode)
304 			break;
305 
306 		switch (connector->connector_type) {
307 		case DRM_MODE_CONNECTOR_LVDS:
308 		case DRM_MODE_CONNECTOR_eDP:
309 		case DRM_MODE_CONNECTOR_DSI:
310 			/*
311 			 * Integrated displays have a specific address 0x1f on
312 			 * most Intel platforms, but not on all of them.
313 			 */
314 			adev = acpi_find_child_device(ACPI_COMPANION(drm_dev->dev),
315 						      0x1f, 0);
316 			if (adev) {
317 				connector->fwnode =
318 					fwnode_handle_get(acpi_fwnode_handle(adev));
319 				break;
320 			}
321 			fallthrough;
322 		default:
323 			connector->fwnode = fwnode_handle_get(fwnode);
324 			break;
325 		}
326 	}
327 	drm_connector_list_iter_end(&conn_iter);
328 	/*
329 	 * device_get_next_child_node() takes a reference on the fwnode, if
330 	 * we stopped iterating because we are out of connectors we need to
331 	 * put this, otherwise fwnode is NULL and the put is a no-op.
332 	 */
333 	fwnode_handle_put(fwnode);
334 }
335 
336 void intel_acpi_video_register(struct drm_i915_private *i915)
337 {
338 	struct drm_connector_list_iter conn_iter;
339 	struct drm_connector *connector;
340 
341 	acpi_video_register();
342 
343 	/*
344 	 * If i915 is driving an internal panel without registering its native
345 	 * backlight handler try to register the acpi_video backlight.
346 	 * For panels not driven by i915 another GPU driver may still register
347 	 * a native backlight later and acpi_video_register_backlight() should
348 	 * only be called after any native backlights have been registered.
349 	 */
350 	drm_connector_list_iter_begin(&i915->drm, &conn_iter);
351 	drm_for_each_connector_iter(connector, &conn_iter) {
352 		struct intel_panel *panel = &to_intel_connector(connector)->panel;
353 
354 		if (panel->backlight.funcs && !panel->backlight.device) {
355 			acpi_video_register_backlight();
356 			break;
357 		}
358 	}
359 	drm_connector_list_iter_end(&conn_iter);
360 }
361