xref: /linux/drivers/gpu/drm/vboxvideo/vbox_irq.c (revision cbdb1f163af2bb90d01be1f0263df1d8d5c9d9d3)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright (C) 2016-2017 Oracle Corporation
4  * This file is based on qxl_irq.c
5  * Copyright 2013 Red Hat Inc.
6  * Authors: Dave Airlie
7  *          Alon Levy
8  *          Michael Thayer <michael.thayer@oracle.com,
9  *          Hans de Goede <hdegoede@redhat.com>
10  */
11 
12 #include <linux/pci.h>
13 
14 #include <drm/drm_drv.h>
15 #include <drm/drm_probe_helper.h>
16 
17 #include "vbox_drv.h"
18 #include "vboxvideo.h"
19 
20 static void vbox_clear_irq(void)
21 {
22 	outl((u32)~0, VGA_PORT_HGSMI_HOST);
23 }
24 
25 static u32 vbox_get_flags(struct vbox_private *vbox)
26 {
27 	return readl(vbox->guest_heap + HOST_FLAGS_OFFSET);
28 }
29 
30 void vbox_report_hotplug(struct vbox_private *vbox)
31 {
32 	schedule_work(&vbox->hotplug_work);
33 }
34 
35 static irqreturn_t vbox_irq_handler(int irq, void *arg)
36 {
37 	struct drm_device *dev = (struct drm_device *)arg;
38 	struct vbox_private *vbox = to_vbox_dev(dev);
39 	u32 host_flags = vbox_get_flags(vbox);
40 
41 	if (!(host_flags & HGSMIHOSTFLAGS_IRQ))
42 		return IRQ_NONE;
43 
44 	/*
45 	 * Due to a bug in the initial host implementation of hot-plug irqs,
46 	 * the hot-plug and cursor capability flags were never cleared.
47 	 * Fortunately we can tell when they would have been set by checking
48 	 * that the VSYNC flag is not set.
49 	 */
50 	if (host_flags &
51 	    (HGSMIHOSTFLAGS_HOTPLUG | HGSMIHOSTFLAGS_CURSOR_CAPABILITIES) &&
52 	    !(host_flags & HGSMIHOSTFLAGS_VSYNC))
53 		vbox_report_hotplug(vbox);
54 
55 	vbox_clear_irq();
56 
57 	return IRQ_HANDLED;
58 }
59 
60 /*
61  * Check that the position hints provided by the host are suitable for GNOME
62  * shell (i.e. all screens disjoint and hints for all enabled screens) and if
63  * not replace them with default ones.  Providing valid hints improves the
64  * chances that we will get a known screen layout for pointer mapping.
65  */
66 static void validate_or_set_position_hints(struct vbox_private *vbox)
67 {
68 	struct vbva_modehint *hintsi, *hintsj;
69 	bool valid = true;
70 	u16 currentx = 0;
71 	int i, j;
72 
73 	for (i = 0; i < vbox->num_crtcs; ++i) {
74 		for (j = 0; j < i; ++j) {
75 			hintsi = &vbox->last_mode_hints[i];
76 			hintsj = &vbox->last_mode_hints[j];
77 
78 			if (hintsi->enabled && hintsj->enabled) {
79 				if (hintsi->dx >= 0xffff ||
80 				    hintsi->dy >= 0xffff ||
81 				    hintsj->dx >= 0xffff ||
82 				    hintsj->dy >= 0xffff ||
83 				    (hintsi->dx <
84 					hintsj->dx + (hintsj->cx & 0x8fff) &&
85 				     hintsi->dx + (hintsi->cx & 0x8fff) >
86 					hintsj->dx) ||
87 				    (hintsi->dy <
88 					hintsj->dy + (hintsj->cy & 0x8fff) &&
89 				     hintsi->dy + (hintsi->cy & 0x8fff) >
90 					hintsj->dy))
91 					valid = false;
92 			}
93 		}
94 	}
95 	if (!valid)
96 		for (i = 0; i < vbox->num_crtcs; ++i) {
97 			if (vbox->last_mode_hints[i].enabled) {
98 				vbox->last_mode_hints[i].dx = currentx;
99 				vbox->last_mode_hints[i].dy = 0;
100 				currentx +=
101 				    vbox->last_mode_hints[i].cx & 0x8fff;
102 			}
103 		}
104 }
105 
106 /* Query the host for the most recent video mode hints. */
107 static void vbox_update_mode_hints(struct vbox_private *vbox)
108 {
109 	struct drm_connector_list_iter conn_iter;
110 	struct drm_device *dev = &vbox->ddev;
111 	struct drm_connector *connector;
112 	struct vbox_connector *vbox_conn;
113 	struct vbva_modehint *hints;
114 	u16 flags;
115 	bool disconnected;
116 	unsigned int crtc_id;
117 	int ret;
118 
119 	ret = hgsmi_get_mode_hints(vbox->guest_pool, vbox->num_crtcs,
120 				   vbox->last_mode_hints);
121 	if (ret) {
122 		DRM_ERROR("vboxvideo: hgsmi_get_mode_hints failed: %d\n", ret);
123 		return;
124 	}
125 
126 	validate_or_set_position_hints(vbox);
127 
128 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
129 	drm_connector_list_iter_begin(dev, &conn_iter);
130 	drm_for_each_connector_iter(connector, &conn_iter) {
131 		vbox_conn = to_vbox_connector(connector);
132 
133 		hints = &vbox->last_mode_hints[vbox_conn->vbox_crtc->crtc_id];
134 		if (hints->magic != VBVAMODEHINT_MAGIC)
135 			continue;
136 
137 		disconnected = !(hints->enabled);
138 		crtc_id = vbox_conn->vbox_crtc->crtc_id;
139 		vbox_conn->mode_hint.width = hints->cx;
140 		vbox_conn->mode_hint.height = hints->cy;
141 		vbox_conn->vbox_crtc->x_hint = hints->dx;
142 		vbox_conn->vbox_crtc->y_hint = hints->dy;
143 		vbox_conn->mode_hint.disconnected = disconnected;
144 
145 		if (vbox_conn->vbox_crtc->disconnected == disconnected)
146 			continue;
147 
148 		if (disconnected)
149 			flags = VBVA_SCREEN_F_ACTIVE | VBVA_SCREEN_F_DISABLED;
150 		else
151 			flags = VBVA_SCREEN_F_ACTIVE | VBVA_SCREEN_F_BLANK;
152 
153 		hgsmi_process_display_info(vbox->guest_pool, crtc_id, 0, 0, 0,
154 					   hints->cx * 4, hints->cx,
155 					   hints->cy, 0, flags);
156 
157 		vbox_conn->vbox_crtc->disconnected = disconnected;
158 	}
159 	drm_connector_list_iter_end(&conn_iter);
160 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
161 }
162 
163 static void vbox_hotplug_worker(struct work_struct *work)
164 {
165 	struct vbox_private *vbox = container_of(work, struct vbox_private,
166 						 hotplug_work);
167 
168 	vbox_update_mode_hints(vbox);
169 	drm_kms_helper_hotplug_event(&vbox->ddev);
170 }
171 
172 int vbox_irq_init(struct vbox_private *vbox)
173 {
174 	struct drm_device *dev = &vbox->ddev;
175 	struct pci_dev *pdev = to_pci_dev(dev->dev);
176 
177 	INIT_WORK(&vbox->hotplug_work, vbox_hotplug_worker);
178 	vbox_update_mode_hints(vbox);
179 
180 	/* PCI devices require shared interrupts. */
181 	return request_irq(pdev->irq, vbox_irq_handler, IRQF_SHARED, dev->driver->name, dev);
182 }
183 
184 void vbox_irq_fini(struct vbox_private *vbox)
185 {
186 	struct drm_device *dev = &vbox->ddev;
187 	struct pci_dev *pdev = to_pci_dev(dev->dev);
188 
189 	free_irq(pdev->irq, dev);
190 	flush_work(&vbox->hotplug_work);
191 }
192