xref: /openbmc/qemu/hw/display/bochs-display.c (revision 93e0932b)
1 /*
2  * QEMU PCI bochs display adapter.
3  *
4  * This work is licensed under the terms of the GNU GPL, version 2 or later.
5  * See the COPYING file in the top-level directory.
6  */
7 
8 #include "qemu/osdep.h"
9 #include "qemu/module.h"
10 #include "qemu/units.h"
11 #include "hw/pci/pci_device.h"
12 #include "hw/qdev-properties.h"
13 #include "migration/vmstate.h"
14 #include "hw/display/bochs-vbe.h"
15 #include "hw/display/edid.h"
16 
17 #include "qapi/error.h"
18 
19 #include "ui/console.h"
20 #include "ui/qemu-pixman.h"
21 #include "qom/object.h"
22 
23 typedef struct BochsDisplayMode {
24     pixman_format_code_t format;
25     uint32_t             bytepp;
26     uint32_t             width;
27     uint32_t             height;
28     uint32_t             stride;
29     uint64_t             offset;
30     uint64_t             size;
31 } BochsDisplayMode;
32 
33 struct BochsDisplayState {
34     /* parent */
35     PCIDevice        pci;
36 
37     /* device elements */
38     QemuConsole      *con;
39     MemoryRegion     vram;
40     MemoryRegion     mmio;
41     MemoryRegion     vbe;
42     MemoryRegion     qext;
43     MemoryRegion     edid;
44 
45     /* device config */
46     uint64_t         vgamem;
47     bool             enable_edid;
48     qemu_edid_info   edid_info;
49     uint8_t          edid_blob[256];
50 
51     /* device registers */
52     uint16_t         vbe_regs[VBE_DISPI_INDEX_NB];
53     bool             big_endian_fb;
54 
55     /* device state */
56     BochsDisplayMode mode;
57 };
58 
59 #define TYPE_BOCHS_DISPLAY "bochs-display"
60 OBJECT_DECLARE_SIMPLE_TYPE(BochsDisplayState, BOCHS_DISPLAY)
61 
62 static const VMStateDescription vmstate_bochs_display = {
63     .name = "bochs-display",
64     .fields = (VMStateField[]) {
65         VMSTATE_PCI_DEVICE(pci, BochsDisplayState),
66         VMSTATE_UINT16_ARRAY(vbe_regs, BochsDisplayState, VBE_DISPI_INDEX_NB),
67         VMSTATE_BOOL(big_endian_fb, BochsDisplayState),
68         VMSTATE_END_OF_LIST()
69     }
70 };
71 
72 static uint64_t bochs_display_vbe_read(void *ptr, hwaddr addr,
73                                        unsigned size)
74 {
75     BochsDisplayState *s = ptr;
76     unsigned int index = addr >> 1;
77 
78     switch (index) {
79     case VBE_DISPI_INDEX_ID:
80         return VBE_DISPI_ID5;
81     case VBE_DISPI_INDEX_VIDEO_MEMORY_64K:
82         return s->vgamem / (64 * KiB);
83     }
84 
85     if (index >= ARRAY_SIZE(s->vbe_regs)) {
86         return -1;
87     }
88     return s->vbe_regs[index];
89 }
90 
91 static void bochs_display_vbe_write(void *ptr, hwaddr addr,
92                                     uint64_t val, unsigned size)
93 {
94     BochsDisplayState *s = ptr;
95     unsigned int index = addr >> 1;
96 
97     if (index >= ARRAY_SIZE(s->vbe_regs)) {
98         return;
99     }
100     s->vbe_regs[index] = val;
101 }
102 
103 static const MemoryRegionOps bochs_display_vbe_ops = {
104     .read = bochs_display_vbe_read,
105     .write = bochs_display_vbe_write,
106     .valid.min_access_size = 1,
107     .valid.max_access_size = 4,
108     .impl.min_access_size = 2,
109     .impl.max_access_size = 2,
110     .endianness = DEVICE_LITTLE_ENDIAN,
111 };
112 
113 static uint64_t bochs_display_qext_read(void *ptr, hwaddr addr,
114                                         unsigned size)
115 {
116     BochsDisplayState *s = ptr;
117 
118     switch (addr) {
119     case PCI_VGA_QEXT_REG_SIZE:
120         return PCI_VGA_QEXT_SIZE;
121     case PCI_VGA_QEXT_REG_BYTEORDER:
122         return s->big_endian_fb ?
123             PCI_VGA_QEXT_BIG_ENDIAN : PCI_VGA_QEXT_LITTLE_ENDIAN;
124     default:
125         return 0;
126     }
127 }
128 
129 static void bochs_display_qext_write(void *ptr, hwaddr addr,
130                                      uint64_t val, unsigned size)
131 {
132     BochsDisplayState *s = ptr;
133 
134     switch (addr) {
135     case PCI_VGA_QEXT_REG_BYTEORDER:
136         if (val == PCI_VGA_QEXT_BIG_ENDIAN) {
137             s->big_endian_fb = true;
138         }
139         if (val == PCI_VGA_QEXT_LITTLE_ENDIAN) {
140             s->big_endian_fb = false;
141         }
142         break;
143     }
144 }
145 
146 static const MemoryRegionOps bochs_display_qext_ops = {
147     .read = bochs_display_qext_read,
148     .write = bochs_display_qext_write,
149     .valid.min_access_size = 4,
150     .valid.max_access_size = 4,
151     .endianness = DEVICE_LITTLE_ENDIAN,
152 };
153 
154 static int bochs_display_get_mode(BochsDisplayState *s,
155                                    BochsDisplayMode *mode)
156 {
157     uint16_t *vbe = s->vbe_regs;
158     uint32_t virt_width;
159 
160     if (!(vbe[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED)) {
161         return -1;
162     }
163 
164     memset(mode, 0, sizeof(*mode));
165     switch (vbe[VBE_DISPI_INDEX_BPP]) {
166     case 16:
167         /* best effort: support native endianess only */
168         mode->format = PIXMAN_r5g6b5;
169         mode->bytepp = 2;
170         break;
171     case 32:
172         mode->format = s->big_endian_fb
173             ? PIXMAN_BE_x8r8g8b8
174             : PIXMAN_LE_x8r8g8b8;
175         mode->bytepp = 4;
176         break;
177     default:
178         return -1;
179     }
180 
181     mode->width  = vbe[VBE_DISPI_INDEX_XRES];
182     mode->height = vbe[VBE_DISPI_INDEX_YRES];
183     virt_width  = vbe[VBE_DISPI_INDEX_VIRT_WIDTH];
184     if (virt_width < mode->width) {
185         virt_width = mode->width;
186     }
187     mode->stride = virt_width * mode->bytepp;
188     mode->size   = (uint64_t)mode->stride * mode->height;
189     mode->offset = ((uint64_t)vbe[VBE_DISPI_INDEX_X_OFFSET] * mode->bytepp +
190                     (uint64_t)vbe[VBE_DISPI_INDEX_Y_OFFSET] * mode->stride);
191 
192     if (mode->width < 64 || mode->height < 64) {
193         return -1;
194     }
195     if (mode->offset + mode->size > s->vgamem) {
196         return -1;
197     }
198     return 0;
199 }
200 
201 static void bochs_display_update(void *opaque)
202 {
203     BochsDisplayState *s = opaque;
204     DirtyBitmapSnapshot *snap = NULL;
205     bool full_update = false;
206     BochsDisplayMode mode;
207     DisplaySurface *ds;
208     uint8_t *ptr;
209     bool dirty;
210     int y, ys, ret;
211 
212     ret = bochs_display_get_mode(s, &mode);
213     if (ret < 0) {
214         /* no (valid) video mode */
215         return;
216     }
217 
218     if (memcmp(&s->mode, &mode, sizeof(mode)) != 0) {
219         /* video mode switch */
220         s->mode = mode;
221         ptr = memory_region_get_ram_ptr(&s->vram);
222         ds = qemu_create_displaysurface_from(mode.width,
223                                              mode.height,
224                                              mode.format,
225                                              mode.stride,
226                                              ptr + mode.offset);
227         dpy_gfx_replace_surface(s->con, ds);
228         full_update = true;
229     }
230 
231     if (full_update) {
232         dpy_gfx_update_full(s->con);
233     } else {
234         snap = memory_region_snapshot_and_clear_dirty(&s->vram,
235                                                       mode.offset, mode.size,
236                                                       DIRTY_MEMORY_VGA);
237         ys = -1;
238         for (y = 0; y < mode.height; y++) {
239             dirty = memory_region_snapshot_get_dirty(&s->vram, snap,
240                                                      mode.offset + mode.stride * y,
241                                                      mode.stride);
242             if (dirty && ys < 0) {
243                 ys = y;
244             }
245             if (!dirty && ys >= 0) {
246                 dpy_gfx_update(s->con, 0, ys,
247                                mode.width, y - ys);
248                 ys = -1;
249             }
250         }
251         if (ys >= 0) {
252             dpy_gfx_update(s->con, 0, ys,
253                            mode.width, y - ys);
254         }
255 
256         g_free(snap);
257     }
258 }
259 
260 static const GraphicHwOps bochs_display_gfx_ops = {
261     .gfx_update = bochs_display_update,
262 };
263 
264 static void bochs_display_realize(PCIDevice *dev, Error **errp)
265 {
266     BochsDisplayState *s = BOCHS_DISPLAY(dev);
267     Object *obj = OBJECT(dev);
268     int ret;
269 
270     if (s->vgamem < 4 * MiB) {
271         error_setg(errp, "bochs-display: video memory too small");
272         return;
273     }
274     if (s->vgamem > 256 * MiB) {
275         error_setg(errp, "bochs-display: video memory too big");
276         return;
277     }
278     s->vgamem = pow2ceil(s->vgamem);
279 
280     s->con = graphic_console_init(DEVICE(dev), 0, &bochs_display_gfx_ops, s);
281 
282     memory_region_init_ram(&s->vram, obj, "bochs-display-vram", s->vgamem,
283                            &error_fatal);
284     memory_region_init_io(&s->vbe, obj, &bochs_display_vbe_ops, s,
285                           "bochs dispi interface", PCI_VGA_BOCHS_SIZE);
286     memory_region_init_io(&s->qext, obj, &bochs_display_qext_ops, s,
287                           "qemu extended regs", PCI_VGA_QEXT_SIZE);
288 
289     memory_region_init_io(&s->mmio, obj, &unassigned_io_ops, NULL,
290                           "bochs-display-mmio", PCI_VGA_MMIO_SIZE);
291     memory_region_add_subregion(&s->mmio, PCI_VGA_BOCHS_OFFSET, &s->vbe);
292     memory_region_add_subregion(&s->mmio, PCI_VGA_QEXT_OFFSET, &s->qext);
293 
294     pci_set_byte(&s->pci.config[PCI_REVISION_ID], 2);
295     pci_register_bar(&s->pci, 0, PCI_BASE_ADDRESS_MEM_PREFETCH, &s->vram);
296     pci_register_bar(&s->pci, 2, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->mmio);
297 
298     if (s->enable_edid) {
299         qemu_edid_generate(s->edid_blob, sizeof(s->edid_blob), &s->edid_info);
300         qemu_edid_region_io(&s->edid, obj, s->edid_blob, sizeof(s->edid_blob));
301         memory_region_add_subregion(&s->mmio, 0, &s->edid);
302     }
303 
304     if (pci_bus_is_express(pci_get_bus(dev))) {
305         ret = pcie_endpoint_cap_init(dev, 0x80);
306         assert(ret > 0);
307     } else {
308         dev->cap_present &= ~QEMU_PCI_CAP_EXPRESS;
309     }
310 
311     memory_region_set_log(&s->vram, true, DIRTY_MEMORY_VGA);
312 }
313 
314 static bool bochs_display_get_big_endian_fb(Object *obj, Error **errp)
315 {
316     BochsDisplayState *s = BOCHS_DISPLAY(obj);
317 
318     return s->big_endian_fb;
319 }
320 
321 static void bochs_display_set_big_endian_fb(Object *obj, bool value,
322                                             Error **errp)
323 {
324     BochsDisplayState *s = BOCHS_DISPLAY(obj);
325 
326     s->big_endian_fb = value;
327 }
328 
329 static void bochs_display_init(Object *obj)
330 {
331     PCIDevice *dev = PCI_DEVICE(obj);
332 
333     /* Expose framebuffer byteorder via QOM */
334     object_property_add_bool(obj, "big-endian-framebuffer",
335                              bochs_display_get_big_endian_fb,
336                              bochs_display_set_big_endian_fb);
337 
338     dev->cap_present |= QEMU_PCI_CAP_EXPRESS;
339 }
340 
341 static void bochs_display_exit(PCIDevice *dev)
342 {
343     BochsDisplayState *s = BOCHS_DISPLAY(dev);
344 
345     graphic_console_close(s->con);
346 }
347 
348 static Property bochs_display_properties[] = {
349     DEFINE_PROP_SIZE("vgamem", BochsDisplayState, vgamem, 16 * MiB),
350     DEFINE_PROP_BOOL("edid", BochsDisplayState, enable_edid, true),
351     DEFINE_EDID_PROPERTIES(BochsDisplayState, edid_info),
352     DEFINE_PROP_END_OF_LIST(),
353 };
354 
355 static void bochs_display_class_init(ObjectClass *klass, void *data)
356 {
357     DeviceClass *dc = DEVICE_CLASS(klass);
358     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
359 
360     k->class_id  = PCI_CLASS_DISPLAY_OTHER;
361     k->vendor_id = PCI_VENDOR_ID_QEMU;
362     k->device_id = PCI_DEVICE_ID_QEMU_VGA;
363 
364     k->realize   = bochs_display_realize;
365     k->romfile   = "vgabios-bochs-display.bin";
366     k->exit      = bochs_display_exit;
367     dc->vmsd     = &vmstate_bochs_display;
368     device_class_set_props(dc, bochs_display_properties);
369     set_bit(DEVICE_CATEGORY_DISPLAY, dc->categories);
370 }
371 
372 static const TypeInfo bochs_display_type_info = {
373     .name           = TYPE_BOCHS_DISPLAY,
374     .parent         = TYPE_PCI_DEVICE,
375     .instance_size  = sizeof(BochsDisplayState),
376     .instance_init  = bochs_display_init,
377     .class_init     = bochs_display_class_init,
378     .interfaces     = (InterfaceInfo[]) {
379         { INTERFACE_PCIE_DEVICE },
380         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
381         { },
382     },
383 };
384 
385 static void bochs_display_register_types(void)
386 {
387     type_register_static(&bochs_display_type_info);
388 }
389 
390 type_init(bochs_display_register_types)
391