1 // SPDX-License-Identifier: MIT
2 #include <linux/vgaarb.h>
3 #include <linux/vga_switcheroo.h>
4 
5 #include <drm/drm_fb_helper.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 = nouveau_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 drm_device *dev = pci_get_drvdata(pdev);
38 
39 	if ((nouveau_is_optimus() || nouveau_is_v1_dsm()) && state == VGA_SWITCHEROO_OFF)
40 		return;
41 
42 	if (state == VGA_SWITCHEROO_ON) {
43 		pr_err("VGA switcheroo: switched nouveau on\n");
44 		dev->switch_power_state = DRM_SWITCH_POWER_CHANGING;
45 		nouveau_pmops_resume(&pdev->dev);
46 		dev->switch_power_state = DRM_SWITCH_POWER_ON;
47 	} else {
48 		pr_err("VGA switcheroo: switched nouveau off\n");
49 		dev->switch_power_state = DRM_SWITCH_POWER_CHANGING;
50 		nouveau_switcheroo_optimus_dsm();
51 		nouveau_pmops_suspend(&pdev->dev);
52 		dev->switch_power_state = DRM_SWITCH_POWER_OFF;
53 	}
54 }
55 
56 static void
57 nouveau_switcheroo_reprobe(struct pci_dev *pdev)
58 {
59 	struct drm_device *dev = pci_get_drvdata(pdev);
60 	drm_fb_helper_output_poll_changed(dev);
61 }
62 
63 static bool
64 nouveau_switcheroo_can_switch(struct pci_dev *pdev)
65 {
66 	struct drm_device *dev = pci_get_drvdata(pdev);
67 
68 	/*
69 	 * FIXME: open_count is protected by drm_global_mutex but that would lead to
70 	 * locking inversion with the driver load path. And the access here is
71 	 * completely racy anyway. So don't bother with locking for now.
72 	 */
73 	return atomic_read(&dev->open_count) == 0;
74 }
75 
76 static const struct vga_switcheroo_client_ops
77 nouveau_switcheroo_ops = {
78 	.set_gpu_state = nouveau_switcheroo_set_state,
79 	.reprobe = nouveau_switcheroo_reprobe,
80 	.can_switch = nouveau_switcheroo_can_switch,
81 };
82 
83 void
84 nouveau_vga_init(struct nouveau_drm *drm)
85 {
86 	struct drm_device *dev = drm->dev;
87 	bool runtime = nouveau_pmops_runtime();
88 	struct pci_dev *pdev;
89 
90 	/* only relevant for PCI devices */
91 	if (!dev_is_pci(dev->dev))
92 		return;
93 	pdev = to_pci_dev(dev->dev);
94 
95 	vga_client_register(pdev, nouveau_vga_set_decode);
96 
97 	/* don't register Thunderbolt eGPU with vga_switcheroo */
98 	if (pci_is_thunderbolt_attached(pdev))
99 		return;
100 
101 	vga_switcheroo_register_client(pdev, &nouveau_switcheroo_ops, runtime);
102 
103 	if (runtime && nouveau_is_v1_dsm() && !nouveau_is_optimus())
104 		vga_switcheroo_init_domain_pm_ops(drm->dev->dev, &drm->vga_pm_domain);
105 }
106 
107 void
108 nouveau_vga_fini(struct nouveau_drm *drm)
109 {
110 	struct drm_device *dev = drm->dev;
111 	bool runtime = nouveau_pmops_runtime();
112 	struct pci_dev *pdev;
113 
114 	/* only relevant for PCI devices */
115 	if (!dev_is_pci(dev->dev))
116 		return;
117 	pdev = to_pci_dev(dev->dev);
118 
119 	vga_client_unregister(pdev);
120 
121 	if (pci_is_thunderbolt_attached(pdev))
122 		return;
123 
124 	vga_switcheroo_unregister_client(pdev);
125 	if (runtime && nouveau_is_v1_dsm() && !nouveau_is_optimus())
126 		vga_switcheroo_fini_domain_pm_ops(drm->dev->dev);
127 }
128 
129 
130 void
131 nouveau_vga_lastclose(struct drm_device *dev)
132 {
133 	vga_switcheroo_process_delayed_switch();
134 }
135