xref: /openbmc/qemu/hw/vfio/display.c (revision 6779a3076f295fafe52d43049fa954426c1d594a)
1 /*
2  * display support for mdev based vgpu devices
3  *
4  * Copyright Red Hat, Inc. 2017
5  *
6  * Authors:
7  *    Gerd Hoffmann
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2.  See
10  * the COPYING file in the top-level directory.
11  */
12 
13 #include "qemu/osdep.h"
14 #include <linux/vfio.h>
15 #include <sys/ioctl.h>
16 
17 #include "qemu/error-report.h"
18 #include "hw/display/edid.h"
19 #include "ui/console.h"
20 #include "qapi/error.h"
21 #include "pci.h"
22 #include "trace.h"
23 
24 #ifndef DRM_PLANE_TYPE_PRIMARY
25 # define DRM_PLANE_TYPE_PRIMARY 1
26 # define DRM_PLANE_TYPE_CURSOR  2
27 #endif
28 
29 #define pread_field(_fd, _reg, _ptr, _fld)                              \
30     (sizeof(_ptr->_fld) !=                                              \
31      pread(_fd, &(_ptr->_fld), sizeof(_ptr->_fld),                      \
32            _reg->offset + offsetof(typeof(*_ptr), _fld)))
33 
34 #define pwrite_field(_fd, _reg, _ptr, _fld)                             \
35     (sizeof(_ptr->_fld) !=                                              \
36      pwrite(_fd, &(_ptr->_fld), sizeof(_ptr->_fld),                     \
37             _reg->offset + offsetof(typeof(*_ptr), _fld)))
38 
39 
40 static void vfio_display_edid_link_up(void *opaque)
41 {
42     VFIOPCIDevice *vdev = opaque;
43     VFIODisplay *dpy = vdev->dpy;
44     int fd = vdev->vbasedev.fd;
45 
46     dpy->edid_regs->link_state = VFIO_DEVICE_GFX_LINK_STATE_UP;
47     if (pwrite_field(fd, dpy->edid_info, dpy->edid_regs, link_state)) {
48         goto err;
49     }
50     trace_vfio_display_edid_link_up();
51     return;
52 
53 err:
54     trace_vfio_display_edid_write_error();
55 }
56 
57 static void vfio_display_edid_update(VFIOPCIDevice *vdev, bool enabled,
58                                      int prefx, int prefy)
59 {
60     VFIODisplay *dpy = vdev->dpy;
61     int fd = vdev->vbasedev.fd;
62     qemu_edid_info edid = {
63         .maxx  = dpy->edid_regs->max_xres,
64         .maxy  = dpy->edid_regs->max_yres,
65         .prefx = prefx ?: vdev->display_xres,
66         .prefy = prefy ?: vdev->display_yres,
67     };
68 
69     timer_del(dpy->edid_link_timer);
70     dpy->edid_regs->link_state = VFIO_DEVICE_GFX_LINK_STATE_DOWN;
71     if (pwrite_field(fd, dpy->edid_info, dpy->edid_regs, link_state)) {
72         goto err;
73     }
74     trace_vfio_display_edid_link_down();
75 
76     if (!enabled) {
77         return;
78     }
79 
80     if (edid.maxx && edid.prefx > edid.maxx) {
81         edid.prefx = edid.maxx;
82     }
83     if (edid.maxy && edid.prefy > edid.maxy) {
84         edid.prefy = edid.maxy;
85     }
86     qemu_edid_generate(dpy->edid_blob,
87                        dpy->edid_regs->edid_max_size,
88                        &edid);
89     trace_vfio_display_edid_update(edid.prefx, edid.prefy);
90 
91     dpy->edid_regs->edid_size = qemu_edid_size(dpy->edid_blob);
92     if (pwrite_field(fd, dpy->edid_info, dpy->edid_regs, edid_size)) {
93         goto err;
94     }
95     if (pwrite(fd, dpy->edid_blob, dpy->edid_regs->edid_size,
96                dpy->edid_info->offset + dpy->edid_regs->edid_offset)
97         != dpy->edid_regs->edid_size) {
98         goto err;
99     }
100 
101     timer_mod(dpy->edid_link_timer,
102               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 100);
103     return;
104 
105 err:
106     trace_vfio_display_edid_write_error();
107     return;
108 }
109 
110 static void vfio_display_edid_ui_info(void *opaque, uint32_t idx,
111                                       QemuUIInfo *info)
112 {
113     VFIOPCIDevice *vdev = opaque;
114     VFIODisplay *dpy = vdev->dpy;
115 
116     if (!dpy->edid_regs) {
117         return;
118     }
119 
120     if (info->width && info->height) {
121         vfio_display_edid_update(vdev, true, info->width, info->height);
122     } else {
123         vfio_display_edid_update(vdev, false, 0, 0);
124     }
125 }
126 
127 static void vfio_display_edid_init(VFIOPCIDevice *vdev)
128 {
129     VFIODisplay *dpy = vdev->dpy;
130     int fd = vdev->vbasedev.fd;
131     int ret;
132 
133     ret = vfio_get_dev_region_info(&vdev->vbasedev,
134                                    VFIO_REGION_TYPE_GFX,
135                                    VFIO_REGION_SUBTYPE_GFX_EDID,
136                                    &dpy->edid_info);
137     if (ret) {
138         return;
139     }
140 
141     trace_vfio_display_edid_available();
142     dpy->edid_regs = g_new0(struct vfio_region_gfx_edid, 1);
143     if (pread_field(fd, dpy->edid_info, dpy->edid_regs, edid_offset)) {
144         goto err;
145     }
146     if (pread_field(fd, dpy->edid_info, dpy->edid_regs, edid_max_size)) {
147         goto err;
148     }
149     if (pread_field(fd, dpy->edid_info, dpy->edid_regs, max_xres)) {
150         goto err;
151     }
152     if (pread_field(fd, dpy->edid_info, dpy->edid_regs, max_yres)) {
153         goto err;
154     }
155 
156     dpy->edid_blob = g_malloc0(dpy->edid_regs->edid_max_size);
157 
158     /* if xres + yres properties are unset use the maximum resolution */
159     if (!vdev->display_xres) {
160         vdev->display_xres = dpy->edid_regs->max_xres;
161     }
162     if (!vdev->display_yres) {
163         vdev->display_yres = dpy->edid_regs->max_yres;
164     }
165 
166     dpy->edid_link_timer = timer_new_ms(QEMU_CLOCK_REALTIME,
167                                         vfio_display_edid_link_up, vdev);
168 
169     vfio_display_edid_update(vdev, true, 0, 0);
170     return;
171 
172 err:
173     trace_vfio_display_edid_write_error();
174     g_free(dpy->edid_regs);
175     dpy->edid_regs = NULL;
176     return;
177 }
178 
179 static void vfio_display_edid_exit(VFIODisplay *dpy)
180 {
181     if (!dpy->edid_regs) {
182         return;
183     }
184 
185     g_free(dpy->edid_regs);
186     g_free(dpy->edid_blob);
187     timer_free(dpy->edid_link_timer);
188 }
189 
190 static void vfio_display_update_cursor(VFIODMABuf *dmabuf,
191                                        struct vfio_device_gfx_plane_info *plane)
192 {
193     if (dmabuf->pos_x != plane->x_pos || dmabuf->pos_y != plane->y_pos) {
194         dmabuf->pos_x      = plane->x_pos;
195         dmabuf->pos_y      = plane->y_pos;
196         dmabuf->pos_updates++;
197     }
198     if (dmabuf->hot_x != plane->x_hot || dmabuf->hot_y != plane->y_hot) {
199         dmabuf->hot_x      = plane->x_hot;
200         dmabuf->hot_y      = plane->y_hot;
201         dmabuf->hot_updates++;
202     }
203 }
204 
205 static VFIODMABuf *vfio_display_get_dmabuf(VFIOPCIDevice *vdev,
206                                            uint32_t plane_type)
207 {
208     VFIODisplay *dpy = vdev->dpy;
209     struct vfio_device_gfx_plane_info plane;
210     VFIODMABuf *dmabuf;
211     int fd, ret;
212 
213     memset(&plane, 0, sizeof(plane));
214     plane.argsz = sizeof(plane);
215     plane.flags = VFIO_GFX_PLANE_TYPE_DMABUF;
216     plane.drm_plane_type = plane_type;
217     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_QUERY_GFX_PLANE, &plane);
218     if (ret < 0) {
219         return NULL;
220     }
221     if (!plane.drm_format || !plane.size) {
222         return NULL;
223     }
224 
225     QTAILQ_FOREACH(dmabuf, &dpy->dmabuf.bufs, next) {
226         if (dmabuf->dmabuf_id == plane.dmabuf_id) {
227             /* found in list, move to head, return it */
228             QTAILQ_REMOVE(&dpy->dmabuf.bufs, dmabuf, next);
229             QTAILQ_INSERT_HEAD(&dpy->dmabuf.bufs, dmabuf, next);
230             if (plane_type == DRM_PLANE_TYPE_CURSOR) {
231                 vfio_display_update_cursor(dmabuf, &plane);
232             }
233             return dmabuf;
234         }
235     }
236 
237     fd = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_GFX_DMABUF, &plane.dmabuf_id);
238     if (fd < 0) {
239         return NULL;
240     }
241 
242     dmabuf = g_new0(VFIODMABuf, 1);
243     dmabuf->dmabuf_id  = plane.dmabuf_id;
244     dmabuf->buf.width  = plane.width;
245     dmabuf->buf.height = plane.height;
246     dmabuf->buf.backing_width = plane.width;
247     dmabuf->buf.backing_height = plane.height;
248     dmabuf->buf.stride = plane.stride;
249     dmabuf->buf.fourcc = plane.drm_format;
250     dmabuf->buf.modifier = plane.drm_format_mod;
251     dmabuf->buf.fd     = fd;
252     if (plane_type == DRM_PLANE_TYPE_CURSOR) {
253         vfio_display_update_cursor(dmabuf, &plane);
254     }
255 
256     QTAILQ_INSERT_HEAD(&dpy->dmabuf.bufs, dmabuf, next);
257     return dmabuf;
258 }
259 
260 static void vfio_display_free_one_dmabuf(VFIODisplay *dpy, VFIODMABuf *dmabuf)
261 {
262     QTAILQ_REMOVE(&dpy->dmabuf.bufs, dmabuf, next);
263 
264     qemu_dmabuf_close(&dmabuf->buf);
265     dpy_gl_release_dmabuf(dpy->con, &dmabuf->buf);
266     g_free(dmabuf);
267 }
268 
269 static void vfio_display_free_dmabufs(VFIOPCIDevice *vdev)
270 {
271     VFIODisplay *dpy = vdev->dpy;
272     VFIODMABuf *dmabuf, *tmp;
273     uint32_t keep = 5;
274 
275     QTAILQ_FOREACH_SAFE(dmabuf, &dpy->dmabuf.bufs, next, tmp) {
276         if (keep > 0) {
277             keep--;
278             continue;
279         }
280         assert(dmabuf != dpy->dmabuf.primary);
281         vfio_display_free_one_dmabuf(dpy, dmabuf);
282     }
283 }
284 
285 static void vfio_display_dmabuf_update(void *opaque)
286 {
287     VFIOPCIDevice *vdev = opaque;
288     VFIODisplay *dpy = vdev->dpy;
289     VFIODMABuf *primary, *cursor;
290     uint32_t width, height;
291     bool free_bufs = false, new_cursor = false;
292 
293     primary = vfio_display_get_dmabuf(vdev, DRM_PLANE_TYPE_PRIMARY);
294     if (primary == NULL) {
295         if (dpy->ramfb) {
296             ramfb_display_update(dpy->con, dpy->ramfb);
297         }
298         return;
299     }
300 
301     width = qemu_dmabuf_get_width(&primary->buf);
302     height = qemu_dmabuf_get_height(&primary->buf);
303 
304     if (dpy->dmabuf.primary != primary) {
305         dpy->dmabuf.primary = primary;
306         qemu_console_resize(dpy->con, width, height);
307         dpy_gl_scanout_dmabuf(dpy->con, &primary->buf);
308         free_bufs = true;
309     }
310 
311     cursor = vfio_display_get_dmabuf(vdev, DRM_PLANE_TYPE_CURSOR);
312     if (dpy->dmabuf.cursor != cursor) {
313         dpy->dmabuf.cursor = cursor;
314         new_cursor = true;
315         free_bufs = true;
316     }
317 
318     if (cursor && (new_cursor || cursor->hot_updates)) {
319         bool have_hot = (cursor->hot_x != 0xffffffff &&
320                          cursor->hot_y != 0xffffffff);
321         dpy_gl_cursor_dmabuf(dpy->con, &cursor->buf, have_hot,
322                              cursor->hot_x, cursor->hot_y);
323         cursor->hot_updates = 0;
324     } else if (!cursor && new_cursor) {
325         dpy_gl_cursor_dmabuf(dpy->con, NULL, false, 0, 0);
326     }
327 
328     if (cursor && cursor->pos_updates) {
329         dpy_gl_cursor_position(dpy->con,
330                                cursor->pos_x,
331                                cursor->pos_y);
332         cursor->pos_updates = 0;
333     }
334 
335     dpy_gl_update(dpy->con, 0, 0, width, height);
336 
337     if (free_bufs) {
338         vfio_display_free_dmabufs(vdev);
339     }
340 }
341 
342 static int vfio_display_get_flags(void *opaque)
343 {
344     return GRAPHIC_FLAGS_GL | GRAPHIC_FLAGS_DMABUF;
345 }
346 
347 static const GraphicHwOps vfio_display_dmabuf_ops = {
348     .get_flags  = vfio_display_get_flags,
349     .gfx_update = vfio_display_dmabuf_update,
350     .ui_info    = vfio_display_edid_ui_info,
351 };
352 
353 static int vfio_display_dmabuf_init(VFIOPCIDevice *vdev, Error **errp)
354 {
355     if (!display_opengl) {
356         error_setg(errp, "vfio-display-dmabuf: opengl not available");
357         return -1;
358     }
359 
360     vdev->dpy = g_new0(VFIODisplay, 1);
361     vdev->dpy->con = graphic_console_init(DEVICE(vdev), 0,
362                                           &vfio_display_dmabuf_ops,
363                                           vdev);
364     if (vdev->enable_ramfb) {
365         vdev->dpy->ramfb = ramfb_setup(errp);
366     }
367     vfio_display_edid_init(vdev);
368     return 0;
369 }
370 
371 static void vfio_display_dmabuf_exit(VFIODisplay *dpy)
372 {
373     VFIODMABuf *dmabuf;
374 
375     if (QTAILQ_EMPTY(&dpy->dmabuf.bufs)) {
376         return;
377     }
378 
379     while ((dmabuf = QTAILQ_FIRST(&dpy->dmabuf.bufs)) != NULL) {
380         vfio_display_free_one_dmabuf(dpy, dmabuf);
381     }
382 }
383 
384 /* ---------------------------------------------------------------------- */
385 void vfio_display_reset(VFIOPCIDevice *vdev)
386 {
387     if (!vdev || !vdev->dpy || !vdev->dpy->con ||
388         !vdev->dpy->dmabuf.primary) {
389         return;
390     }
391 
392     dpy_gl_scanout_disable(vdev->dpy->con);
393     vfio_display_dmabuf_exit(vdev->dpy);
394     dpy_gfx_update_full(vdev->dpy->con);
395 }
396 
397 static void vfio_display_region_update(void *opaque)
398 {
399     VFIOPCIDevice *vdev = opaque;
400     VFIODisplay *dpy = vdev->dpy;
401     struct vfio_device_gfx_plane_info plane = {
402         .argsz = sizeof(plane),
403         .flags = VFIO_GFX_PLANE_TYPE_REGION
404     };
405     pixman_format_code_t format;
406     int ret;
407 
408     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_QUERY_GFX_PLANE, &plane);
409     if (ret < 0) {
410         error_report("ioctl VFIO_DEVICE_QUERY_GFX_PLANE: %s",
411                      strerror(errno));
412         return;
413     }
414     if (!plane.drm_format || !plane.size) {
415         if (dpy->ramfb) {
416             ramfb_display_update(dpy->con, dpy->ramfb);
417             dpy->region.surface = NULL;
418         }
419         return;
420     }
421     format = qemu_drm_format_to_pixman(plane.drm_format);
422     if (!format) {
423         return;
424     }
425 
426     if (dpy->region.buffer.size &&
427         dpy->region.buffer.nr != plane.region_index) {
428         /* region changed */
429         vfio_region_exit(&dpy->region.buffer);
430         vfio_region_finalize(&dpy->region.buffer);
431         dpy->region.surface = NULL;
432     }
433 
434     if (dpy->region.surface &&
435         (surface_width(dpy->region.surface) != plane.width ||
436          surface_height(dpy->region.surface) != plane.height ||
437          surface_format(dpy->region.surface) != format)) {
438         /* size changed */
439         dpy->region.surface = NULL;
440     }
441 
442     if (!dpy->region.buffer.size) {
443         /* mmap region */
444         ret = vfio_region_setup(OBJECT(vdev), &vdev->vbasedev,
445                                 &dpy->region.buffer,
446                                 plane.region_index,
447                                 "display");
448         if (ret != 0) {
449             error_report("%s: vfio_region_setup(%d): %s",
450                          __func__, plane.region_index, strerror(-ret));
451             goto err;
452         }
453         ret = vfio_region_mmap(&dpy->region.buffer);
454         if (ret != 0) {
455             error_report("%s: vfio_region_mmap(%d): %s", __func__,
456                          plane.region_index, strerror(-ret));
457             goto err;
458         }
459         assert(dpy->region.buffer.mmaps[0].mmap != NULL);
460     }
461 
462     if (dpy->region.surface == NULL) {
463         /* create surface */
464         dpy->region.surface = qemu_create_displaysurface_from
465             (plane.width, plane.height, format,
466              plane.stride, dpy->region.buffer.mmaps[0].mmap);
467         dpy_gfx_replace_surface(dpy->con, dpy->region.surface);
468     }
469 
470     /* full screen update */
471     dpy_gfx_update(dpy->con, 0, 0,
472                    surface_width(dpy->region.surface),
473                    surface_height(dpy->region.surface));
474     return;
475 
476 err:
477     vfio_region_exit(&dpy->region.buffer);
478     vfio_region_finalize(&dpy->region.buffer);
479 }
480 
481 static const GraphicHwOps vfio_display_region_ops = {
482     .gfx_update = vfio_display_region_update,
483 };
484 
485 static int vfio_display_region_init(VFIOPCIDevice *vdev, Error **errp)
486 {
487     vdev->dpy = g_new0(VFIODisplay, 1);
488     vdev->dpy->con = graphic_console_init(DEVICE(vdev), 0,
489                                           &vfio_display_region_ops,
490                                           vdev);
491     if (vdev->enable_ramfb) {
492         vdev->dpy->ramfb = ramfb_setup(errp);
493     }
494     return 0;
495 }
496 
497 static void vfio_display_region_exit(VFIODisplay *dpy)
498 {
499     if (!dpy->region.buffer.size) {
500         return;
501     }
502 
503     vfio_region_exit(&dpy->region.buffer);
504     vfio_region_finalize(&dpy->region.buffer);
505 }
506 
507 /* ---------------------------------------------------------------------- */
508 
509 int vfio_display_probe(VFIOPCIDevice *vdev, Error **errp)
510 {
511     struct vfio_device_gfx_plane_info probe;
512     int ret;
513 
514     memset(&probe, 0, sizeof(probe));
515     probe.argsz = sizeof(probe);
516     probe.flags = VFIO_GFX_PLANE_TYPE_PROBE | VFIO_GFX_PLANE_TYPE_DMABUF;
517     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_QUERY_GFX_PLANE, &probe);
518     if (ret == 0) {
519         return vfio_display_dmabuf_init(vdev, errp);
520     }
521 
522     memset(&probe, 0, sizeof(probe));
523     probe.argsz = sizeof(probe);
524     probe.flags = VFIO_GFX_PLANE_TYPE_PROBE | VFIO_GFX_PLANE_TYPE_REGION;
525     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_QUERY_GFX_PLANE, &probe);
526     if (ret == 0) {
527         return vfio_display_region_init(vdev, errp);
528     }
529 
530     if (vdev->display == ON_OFF_AUTO_AUTO) {
531         /* not an error in automatic mode */
532         return 0;
533     }
534 
535     error_setg(errp, "vfio: device doesn't support any (known) display method");
536     return -1;
537 }
538 
539 void vfio_display_finalize(VFIOPCIDevice *vdev)
540 {
541     if (!vdev->dpy) {
542         return;
543     }
544 
545     graphic_console_close(vdev->dpy->con);
546     vfio_display_dmabuf_exit(vdev->dpy);
547     vfio_display_region_exit(vdev->dpy);
548     vfio_display_edid_exit(vdev->dpy);
549     g_free(vdev->dpy);
550 }
551 
552 static bool migrate_needed(void *opaque)
553 {
554     VFIODisplay *dpy = opaque;
555     bool ramfb_exists = dpy->ramfb != NULL;
556 
557     /* see vfio_display_migration_needed() */
558     assert(ramfb_exists);
559     return ramfb_exists;
560 }
561 
562 const VMStateDescription vfio_display_vmstate = {
563     .name = "VFIODisplay",
564     .version_id = 1,
565     .minimum_version_id = 1,
566     .needed = migrate_needed,
567     .fields = (const VMStateField[]) {
568         VMSTATE_STRUCT_POINTER(ramfb, VFIODisplay, ramfb_vmstate, RAMFBState),
569         VMSTATE_END_OF_LIST(),
570     }
571 };
572