xref: /linux/drivers/gpu/drm/nouveau/nouveau_vga.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: MIT
2 #include <linux/vgaarb.h>
3 #include <linux/vga_switcheroo.h>
4 
5 #include <drm/drm_client_event.h>
6 
7 #include "nouveau_drv.h"
8 #include "nouveau_acpi.h"
9 #include "nouveau_vga.h"
10 
11 static unsigned int
12 nouveau_vga_set_decode(struct pci_dev *pdev, bool state)
13 {
14 	struct nouveau_drm *drm = pci_get_drvdata(pdev);
15 	struct nvif_object *device = &drm->client.device.object;
16 
17 	if (drm->client.device.info.family == NV_DEVICE_INFO_V0_CURIE &&
18 	    drm->client.device.info.chipset >= 0x4c)
19 		nvif_wr32(device, 0x088060, state);
20 	else
21 	if (drm->client.device.info.chipset >= 0x40)
22 		nvif_wr32(device, 0x088054, state);
23 	else
24 		nvif_wr32(device, 0x001854, state);
25 
26 	if (state)
27 		return VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM |
28 		       VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
29 	else
30 		return VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
31 }
32 
33 static void
34 nouveau_switcheroo_set_state(struct pci_dev *pdev,
35 			     enum vga_switcheroo_state state)
36 {
37 	struct nouveau_drm *drm = pci_get_drvdata(pdev);
38 	struct drm_device *dev = drm->dev;
39 
40 	if ((nouveau_is_optimus() || nouveau_is_v1_dsm()) && state == VGA_SWITCHEROO_OFF)
41 		return;
42 
43 	if (state == VGA_SWITCHEROO_ON) {
44 		pr_err("VGA switcheroo: switched nouveau on\n");
45 		dev->switch_power_state = DRM_SWITCH_POWER_CHANGING;
46 		nouveau_pmops_resume(&pdev->dev);
47 		dev->switch_power_state = DRM_SWITCH_POWER_ON;
48 	} else {
49 		pr_err("VGA switcheroo: switched nouveau off\n");
50 		dev->switch_power_state = DRM_SWITCH_POWER_CHANGING;
51 		nouveau_switcheroo_optimus_dsm();
52 		nouveau_pmops_suspend(&pdev->dev);
53 		dev->switch_power_state = DRM_SWITCH_POWER_OFF;
54 	}
55 }
56 
57 static void
58 nouveau_switcheroo_reprobe(struct pci_dev *pdev)
59 {
60 	struct nouveau_drm *drm = pci_get_drvdata(pdev);
61 	struct drm_device *dev = drm->dev;
62 
63 	drm_client_dev_hotplug(dev);
64 }
65 
66 static bool
67 nouveau_switcheroo_can_switch(struct pci_dev *pdev)
68 {
69 	struct nouveau_drm *drm = pci_get_drvdata(pdev);
70 
71 	/*
72 	 * FIXME: open_count is protected by drm_global_mutex but that would lead to
73 	 * locking inversion with the driver load path. And the access here is
74 	 * completely racy anyway. So don't bother with locking for now.
75 	 */
76 	return atomic_read(&drm->dev->open_count) == 0;
77 }
78 
79 static const struct vga_switcheroo_client_ops
80 nouveau_switcheroo_ops = {
81 	.set_gpu_state = nouveau_switcheroo_set_state,
82 	.reprobe = nouveau_switcheroo_reprobe,
83 	.can_switch = nouveau_switcheroo_can_switch,
84 };
85 
86 void
87 nouveau_vga_init(struct nouveau_drm *drm)
88 {
89 	struct drm_device *dev = drm->dev;
90 	bool runtime = nouveau_pmops_runtime();
91 	struct pci_dev *pdev;
92 
93 	/* only relevant for PCI devices */
94 	if (!dev_is_pci(dev->dev))
95 		return;
96 	pdev = to_pci_dev(dev->dev);
97 
98 	vga_client_register(pdev, nouveau_vga_set_decode);
99 
100 	/* don't register Thunderbolt eGPU with vga_switcheroo */
101 	if (pci_is_thunderbolt_attached(pdev))
102 		return;
103 
104 	vga_switcheroo_register_client(pdev, &nouveau_switcheroo_ops, runtime);
105 
106 	if (runtime && nouveau_is_v1_dsm() && !nouveau_is_optimus())
107 		vga_switcheroo_init_domain_pm_ops(drm->dev->dev, &drm->vga_pm_domain);
108 }
109 
110 void
111 nouveau_vga_fini(struct nouveau_drm *drm)
112 {
113 	struct drm_device *dev = drm->dev;
114 	bool runtime = nouveau_pmops_runtime();
115 	struct pci_dev *pdev;
116 
117 	/* only relevant for PCI devices */
118 	if (!dev_is_pci(dev->dev))
119 		return;
120 	pdev = to_pci_dev(dev->dev);
121 
122 	vga_client_unregister(pdev);
123 
124 	if (pci_is_thunderbolt_attached(pdev))
125 		return;
126 
127 	vga_switcheroo_unregister_client(pdev);
128 	if (runtime && nouveau_is_v1_dsm() && !nouveau_is_optimus())
129 		vga_switcheroo_fini_domain_pm_ops(drm->dev->dev);
130 }
131