1 // SPDX-License-Identifier: MIT
2 #include <linux/vgaarb.h>
3 #include <linux/vga_switcheroo.h>
4 
5 #include <drm/drm_crtc_helper.h>
6 #include <drm/drm_fb_helper.h>
7 
8 #include "nouveau_drv.h"
9 #include "nouveau_acpi.h"
10 #include "nouveau_fbcon.h"
11 #include "nouveau_vga.h"
12 
13 static unsigned int
nouveau_vga_set_decode(struct pci_dev * pdev,bool state)14 nouveau_vga_set_decode(struct pci_dev *pdev, bool state)
15 {
16 	struct nouveau_drm *drm = nouveau_drm(pci_get_drvdata(pdev));
17 	struct nvif_object *device = &drm->client.device.object;
18 
19 	if (drm->client.device.info.family == NV_DEVICE_INFO_V0_CURIE &&
20 	    drm->client.device.info.chipset >= 0x4c)
21 		nvif_wr32(device, 0x088060, state);
22 	else
23 	if (drm->client.device.info.chipset >= 0x40)
24 		nvif_wr32(device, 0x088054, state);
25 	else
26 		nvif_wr32(device, 0x001854, state);
27 
28 	if (state)
29 		return VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM |
30 		       VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
31 	else
32 		return VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
33 }
34 
35 static void
nouveau_switcheroo_set_state(struct pci_dev * pdev,enum vga_switcheroo_state state)36 nouveau_switcheroo_set_state(struct pci_dev *pdev,
37 			     enum vga_switcheroo_state state)
38 {
39 	struct drm_device *dev = pci_get_drvdata(pdev);
40 
41 	if ((nouveau_is_optimus() || nouveau_is_v1_dsm()) && state == VGA_SWITCHEROO_OFF)
42 		return;
43 
44 	if (state == VGA_SWITCHEROO_ON) {
45 		pr_err("VGA switcheroo: switched nouveau on\n");
46 		dev->switch_power_state = DRM_SWITCH_POWER_CHANGING;
47 		nouveau_pmops_resume(&pdev->dev);
48 		dev->switch_power_state = DRM_SWITCH_POWER_ON;
49 	} else {
50 		pr_err("VGA switcheroo: switched nouveau off\n");
51 		dev->switch_power_state = DRM_SWITCH_POWER_CHANGING;
52 		nouveau_switcheroo_optimus_dsm();
53 		nouveau_pmops_suspend(&pdev->dev);
54 		dev->switch_power_state = DRM_SWITCH_POWER_OFF;
55 	}
56 }
57 
58 static void
nouveau_switcheroo_reprobe(struct pci_dev * pdev)59 nouveau_switcheroo_reprobe(struct pci_dev *pdev)
60 {
61 	struct drm_device *dev = pci_get_drvdata(pdev);
62 	drm_fb_helper_output_poll_changed(dev);
63 }
64 
65 static bool
nouveau_switcheroo_can_switch(struct pci_dev * pdev)66 nouveau_switcheroo_can_switch(struct pci_dev *pdev)
67 {
68 	struct drm_device *dev = pci_get_drvdata(pdev);
69 
70 	/*
71 	 * FIXME: open_count is protected by drm_global_mutex but that would lead to
72 	 * locking inversion with the driver load path. And the access here is
73 	 * completely racy anyway. So don't bother with locking for now.
74 	 */
75 	return atomic_read(&dev->open_count) == 0;
76 }
77 
78 static const struct vga_switcheroo_client_ops
79 nouveau_switcheroo_ops = {
80 	.set_gpu_state = nouveau_switcheroo_set_state,
81 	.reprobe = nouveau_switcheroo_reprobe,
82 	.can_switch = nouveau_switcheroo_can_switch,
83 };
84 
85 void
nouveau_vga_init(struct nouveau_drm * drm)86 nouveau_vga_init(struct nouveau_drm *drm)
87 {
88 	struct drm_device *dev = drm->dev;
89 	bool runtime = nouveau_pmops_runtime();
90 	struct pci_dev *pdev;
91 
92 	/* only relevant for PCI devices */
93 	if (!dev_is_pci(dev->dev))
94 		return;
95 	pdev = to_pci_dev(dev->dev);
96 
97 	vga_client_register(pdev, nouveau_vga_set_decode);
98 
99 	/* don't register Thunderbolt eGPU with vga_switcheroo */
100 	if (pci_is_thunderbolt_attached(pdev))
101 		return;
102 
103 	vga_switcheroo_register_client(pdev, &nouveau_switcheroo_ops, runtime);
104 
105 	if (runtime && nouveau_is_v1_dsm() && !nouveau_is_optimus())
106 		vga_switcheroo_init_domain_pm_ops(drm->dev->dev, &drm->vga_pm_domain);
107 }
108 
109 void
nouveau_vga_fini(struct nouveau_drm * drm)110 nouveau_vga_fini(struct nouveau_drm *drm)
111 {
112 	struct drm_device *dev = drm->dev;
113 	bool runtime = nouveau_pmops_runtime();
114 	struct pci_dev *pdev;
115 
116 	/* only relevant for PCI devices */
117 	if (!dev_is_pci(dev->dev))
118 		return;
119 	pdev = to_pci_dev(dev->dev);
120 
121 	vga_client_unregister(pdev);
122 
123 	if (pci_is_thunderbolt_attached(pdev))
124 		return;
125 
126 	vga_switcheroo_unregister_client(pdev);
127 	if (runtime && nouveau_is_v1_dsm() && !nouveau_is_optimus())
128 		vga_switcheroo_fini_domain_pm_ops(drm->dev->dev);
129 }
130 
131 
132 void
nouveau_vga_lastclose(struct drm_device * dev)133 nouveau_vga_lastclose(struct drm_device *dev)
134 {
135 	vga_switcheroo_process_delayed_switch();
136 }
137