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