summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/i915/intel_acpi.c
blob: 3456d33feb46aa52dd5e3095034886766ea5192c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
// SPDX-License-Identifier: GPL-2.0
/*
 * Intel ACPI functions
 *
 * _DSM related code stolen from nouveau_acpi.c.
 */

#include <linux/pci.h>
#include <linux/acpi.h>

#include "i915_drv.h"
#include "intel_acpi.h"

#define INTEL_DSM_REVISION_ID 1 /* For Calpella anyway... */
#define INTEL_DSM_FN_PLATFORM_MUX_INFO 1 /* No args */

static const guid_t intel_dsm_guid =
	GUID_INIT(0x7ed873d3, 0xc2d0, 0x4e4f,
		  0xa8, 0x54, 0x0f, 0x13, 0x17, 0xb0, 0x1c, 0x2c);

static char *intel_dsm_port_name(u8 id)
{
	switch (id) {
	case 0:
		return "Reserved";
	case 1:
		return "Analog VGA";
	case 2:
		return "LVDS";
	case 3:
		return "Reserved";
	case 4:
		return "HDMI/DVI_B";
	case 5:
		return "HDMI/DVI_C";
	case 6:
		return "HDMI/DVI_D";
	case 7:
		return "DisplayPort_A";
	case 8:
		return "DisplayPort_B";
	case 9:
		return "DisplayPort_C";
	case 0xa:
		return "DisplayPort_D";
	case 0xb:
	case 0xc:
	case 0xd:
		return "Reserved";
	case 0xe:
		return "WiDi";
	default:
		return "bad type";
	}
}

static char *intel_dsm_mux_type(u8 type)
{
	switch (type) {
	case 0:
		return "unknown";
	case 1:
		return "No MUX, iGPU only";
	case 2:
		return "No MUX, dGPU only";
	case 3:
		return "MUXed between iGPU and dGPU";
	default:
		return "bad type";
	}
}

static void intel_dsm_platform_mux_info(acpi_handle dhandle)
{
	int i;
	union acpi_object *pkg, *connector_count;

	pkg = acpi_evaluate_dsm_typed(dhandle, &intel_dsm_guid,
			INTEL_DSM_REVISION_ID, INTEL_DSM_FN_PLATFORM_MUX_INFO,
			NULL, ACPI_TYPE_PACKAGE);
	if (!pkg) {
		DRM_DEBUG_DRIVER("failed to evaluate _DSM\n");
		return;
	}

	connector_count = &pkg->package.elements[0];
	DRM_DEBUG_DRIVER("MUX info connectors: %lld\n",
		  (unsigned long long)connector_count->integer.value);
	for (i = 1; i < pkg->package.count; i++) {
		union acpi_object *obj = &pkg->package.elements[i];
		union acpi_object *connector_id = &obj->package.elements[0];
		union acpi_object *info = &obj->package.elements[1];
		DRM_DEBUG_DRIVER("Connector id: 0x%016llx\n",
			  (unsigned long long)connector_id->integer.value);
		DRM_DEBUG_DRIVER("  port id: %s\n",
		       intel_dsm_port_name(info->buffer.pointer[0]));
		DRM_DEBUG_DRIVER("  display mux info: %s\n",
		       intel_dsm_mux_type(info->buffer.pointer[1]));
		DRM_DEBUG_DRIVER("  aux/dc mux info: %s\n",
		       intel_dsm_mux_type(info->buffer.pointer[2]));
		DRM_DEBUG_DRIVER("  hpd mux info: %s\n",
		       intel_dsm_mux_type(info->buffer.pointer[3]));
	}

	ACPI_FREE(pkg);
}

static acpi_handle intel_dsm_pci_probe(struct pci_dev *pdev)
{
	acpi_handle dhandle;

	dhandle = ACPI_HANDLE(&pdev->dev);
	if (!dhandle)
		return NULL;

	if (!acpi_check_dsm(dhandle, &intel_dsm_guid, INTEL_DSM_REVISION_ID,
			    1 << INTEL_DSM_FN_PLATFORM_MUX_INFO)) {
		DRM_DEBUG_KMS("no _DSM method for intel device\n");
		return NULL;
	}

	intel_dsm_platform_mux_info(dhandle);

	return dhandle;
}

static bool intel_dsm_detect(void)
{
	acpi_handle dhandle = NULL;
	char acpi_method_name[255] = { 0 };
	struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
	struct pci_dev *pdev = NULL;
	int vga_count = 0;

	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
		vga_count++;
		dhandle = intel_dsm_pci_probe(pdev) ?: dhandle;
	}

	if (vga_count == 2 && dhandle) {
		acpi_get_name(dhandle, ACPI_FULL_PATHNAME, &buffer);
		DRM_DEBUG_DRIVER("vga_switcheroo: detected DSM switching method %s handle\n",
				 acpi_method_name);
		return true;
	}

	return false;
}

void intel_register_dsm_handler(void)
{
	if (!intel_dsm_detect())
		return;
}

void intel_unregister_dsm_handler(void)
{
}