xref: /qemu/hw/display/bochs-display.c (revision 765c94290863eef1fc4a67819d452cc13b7854a1)
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 #include "qemu/osdep.h"
8 #include "hw/hw.h"
9 #include "hw/pci/pci.h"
10 #include "hw/display/bochs-vbe.h"
11 
12 #include "qapi/error.h"
13 
14 #include "ui/console.h"
15 #include "ui/qemu-pixman.h"
16 
17 typedef struct BochsDisplayMode {
18     pixman_format_code_t format;
19     uint32_t             bytepp;
20     uint32_t             width;
21     uint32_t             height;
22     uint32_t             stride;
23     uint64_t             offset;
24     uint64_t             size;
25 } BochsDisplayMode;
26 
27 typedef struct BochsDisplayState {
28     /* parent */
29     PCIDevice        pci;
30 
31     /* device elements */
32     QemuConsole      *con;
33     MemoryRegion     vram;
34     MemoryRegion     mmio;
35     MemoryRegion     vbe;
36     MemoryRegion     qext;
37 
38     /* device config */
39     uint64_t         vgamem;
40 
41     /* device registers */
42     uint16_t         vbe_regs[VBE_DISPI_INDEX_NB];
43     bool             big_endian_fb;
44 
45     /* device state */
46     BochsDisplayMode mode;
47 } BochsDisplayState;
48 
49 #define TYPE_BOCHS_DISPLAY "bochs-display"
50 #define BOCHS_DISPLAY(obj) OBJECT_CHECK(BochsDisplayState, (obj), \
51                                         TYPE_BOCHS_DISPLAY)
52 
53 static const VMStateDescription vmstate_bochs_display = {
54     .name = "bochs-display",
55     .fields = (VMStateField[]) {
56         VMSTATE_PCI_DEVICE(pci, BochsDisplayState),
57         VMSTATE_UINT16_ARRAY(vbe_regs, BochsDisplayState, VBE_DISPI_INDEX_NB),
58         VMSTATE_BOOL(big_endian_fb, BochsDisplayState),
59         VMSTATE_END_OF_LIST()
60     }
61 };
62 
63 static uint64_t bochs_display_vbe_read(void *ptr, hwaddr addr,
64                                        unsigned size)
65 {
66     BochsDisplayState *s = ptr;
67     unsigned int index = addr >> 1;
68 
69     switch (index) {
70     case VBE_DISPI_INDEX_ID:
71         return VBE_DISPI_ID5;
72     case VBE_DISPI_INDEX_VIDEO_MEMORY_64K:
73         return s->vgamem / (64 * 1024);
74     }
75 
76     if (index >= ARRAY_SIZE(s->vbe_regs)) {
77         return -1;
78     }
79     return s->vbe_regs[index];
80 }
81 
82 static void bochs_display_vbe_write(void *ptr, hwaddr addr,
83                                     uint64_t val, unsigned size)
84 {
85     BochsDisplayState *s = ptr;
86     unsigned int index = addr >> 1;
87 
88     if (index >= ARRAY_SIZE(s->vbe_regs)) {
89         return;
90     }
91     s->vbe_regs[index] = val;
92 }
93 
94 static const MemoryRegionOps bochs_display_vbe_ops = {
95     .read = bochs_display_vbe_read,
96     .write = bochs_display_vbe_write,
97     .valid.min_access_size = 1,
98     .valid.max_access_size = 4,
99     .impl.min_access_size = 2,
100     .impl.max_access_size = 2,
101     .endianness = DEVICE_LITTLE_ENDIAN,
102 };
103 
104 static uint64_t bochs_display_qext_read(void *ptr, hwaddr addr,
105                                         unsigned size)
106 {
107     BochsDisplayState *s = ptr;
108 
109     switch (addr) {
110     case PCI_VGA_QEXT_REG_SIZE:
111         return PCI_VGA_QEXT_SIZE;
112     case PCI_VGA_QEXT_REG_BYTEORDER:
113         return s->big_endian_fb ?
114             PCI_VGA_QEXT_BIG_ENDIAN : PCI_VGA_QEXT_LITTLE_ENDIAN;
115     default:
116         return 0;
117     }
118 }
119 
120 static void bochs_display_qext_write(void *ptr, hwaddr addr,
121                                      uint64_t val, unsigned size)
122 {
123     BochsDisplayState *s = ptr;
124 
125     switch (addr) {
126     case PCI_VGA_QEXT_REG_BYTEORDER:
127         if (val == PCI_VGA_QEXT_BIG_ENDIAN) {
128             s->big_endian_fb = true;
129         }
130         if (val == PCI_VGA_QEXT_LITTLE_ENDIAN) {
131             s->big_endian_fb = false;
132         }
133         break;
134     }
135 }
136 
137 static const MemoryRegionOps bochs_display_qext_ops = {
138     .read = bochs_display_qext_read,
139     .write = bochs_display_qext_write,
140     .valid.min_access_size = 4,
141     .valid.max_access_size = 4,
142     .endianness = DEVICE_LITTLE_ENDIAN,
143 };
144 
145 static int bochs_display_get_mode(BochsDisplayState *s,
146                                    BochsDisplayMode *mode)
147 {
148     uint16_t *vbe = s->vbe_regs;
149     uint32_t virt_width;
150 
151     if (!(vbe[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED)) {
152         return -1;
153     }
154 
155     memset(mode, 0, sizeof(*mode));
156     switch (vbe[VBE_DISPI_INDEX_BPP]) {
157     case 16:
158         /* best effort: support native endianess only */
159         mode->format = PIXMAN_r5g6b5;
160         mode->bytepp = 2;
161     case 32:
162         mode->format = s->big_endian_fb
163             ? PIXMAN_BE_x8r8g8b8
164             : PIXMAN_LE_x8r8g8b8;
165         mode->bytepp = 4;
166         break;
167     default:
168         return -1;
169     }
170 
171     mode->width  = vbe[VBE_DISPI_INDEX_XRES];
172     mode->height = vbe[VBE_DISPI_INDEX_YRES];
173     virt_width  = vbe[VBE_DISPI_INDEX_VIRT_WIDTH];
174     if (virt_width < mode->width) {
175         virt_width = mode->width;
176     }
177     mode->stride = virt_width * mode->bytepp;
178     mode->size   = (uint64_t)mode->stride * mode->height;
179     mode->offset = ((uint64_t)vbe[VBE_DISPI_INDEX_X_OFFSET] * mode->bytepp +
180                     (uint64_t)vbe[VBE_DISPI_INDEX_Y_OFFSET] * mode->stride);
181 
182     if (mode->width < 64 || mode->height < 64) {
183         return -1;
184     }
185     if (mode->offset + mode->size > s->vgamem) {
186         return -1;
187     }
188     return 0;
189 }
190 
191 static void bochs_display_update(void *opaque)
192 {
193     BochsDisplayState *s = opaque;
194     BochsDisplayMode mode;
195     DisplaySurface *ds;
196     uint8_t *ptr;
197     int ret;
198 
199     ret = bochs_display_get_mode(s, &mode);
200     if (ret < 0) {
201         /* no (valid) video mode */
202         return;
203     }
204 
205     if (memcmp(&s->mode, &mode, sizeof(mode)) != 0) {
206         /* video mode switch */
207         s->mode = mode;
208         ptr = memory_region_get_ram_ptr(&s->vram);
209         ds = qemu_create_displaysurface_from(mode.width,
210                                              mode.height,
211                                              mode.format,
212                                              mode.stride,
213                                              ptr + mode.offset);
214         dpy_gfx_replace_surface(s->con, ds);
215     }
216 
217     dpy_gfx_update_full(s->con);
218 }
219 
220 static const GraphicHwOps bochs_display_gfx_ops = {
221     .gfx_update = bochs_display_update,
222 };
223 
224 static void bochs_display_realize(PCIDevice *dev, Error **errp)
225 {
226     BochsDisplayState *s = BOCHS_DISPLAY(dev);
227     Object *obj = OBJECT(dev);
228 
229     s->con = graphic_console_init(DEVICE(dev), 0, &bochs_display_gfx_ops, s);
230 
231     if (s->vgamem < (4 * 1024 * 1024)) {
232         error_setg(errp, "bochs-display: video memory too small");
233     }
234     if (s->vgamem > (256 * 1024 * 1024)) {
235         error_setg(errp, "bochs-display: video memory too big");
236     }
237     s->vgamem = pow2ceil(s->vgamem);
238 
239     memory_region_init_ram(&s->vram, obj, "bochs-display-vram", s->vgamem,
240                            &error_fatal);
241     memory_region_init_io(&s->vbe, obj, &bochs_display_vbe_ops, s,
242                           "bochs dispi interface", PCI_VGA_BOCHS_SIZE);
243     memory_region_init_io(&s->qext, obj, &bochs_display_qext_ops, s,
244                           "qemu extended regs", PCI_VGA_QEXT_SIZE);
245 
246     memory_region_init(&s->mmio, obj, "bochs-display-mmio",
247                        PCI_VGA_MMIO_SIZE);
248     memory_region_add_subregion(&s->mmio, PCI_VGA_BOCHS_OFFSET, &s->vbe);
249     memory_region_add_subregion(&s->mmio, PCI_VGA_QEXT_OFFSET, &s->qext);
250 
251     pci_set_byte(&s->pci.config[PCI_REVISION_ID], 2);
252     pci_register_bar(&s->pci, 0, PCI_BASE_ADDRESS_MEM_PREFETCH, &s->vram);
253     pci_register_bar(&s->pci, 2, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->mmio);
254 }
255 
256 static bool bochs_display_get_big_endian_fb(Object *obj, Error **errp)
257 {
258     BochsDisplayState *s = BOCHS_DISPLAY(obj);
259 
260     return s->big_endian_fb;
261 }
262 
263 static void bochs_display_set_big_endian_fb(Object *obj, bool value,
264                                             Error **errp)
265 {
266     BochsDisplayState *s = BOCHS_DISPLAY(obj);
267 
268     s->big_endian_fb = value;
269 }
270 
271 static void bochs_display_init(Object *obj)
272 {
273     /* Expose framebuffer byteorder via QOM */
274     object_property_add_bool(obj, "big-endian-framebuffer",
275                              bochs_display_get_big_endian_fb,
276                              bochs_display_set_big_endian_fb,
277                              NULL);
278 }
279 
280 static void bochs_display_exit(PCIDevice *dev)
281 {
282     BochsDisplayState *s = BOCHS_DISPLAY(dev);
283 
284     graphic_console_close(s->con);
285 }
286 
287 static Property bochs_display_properties[] = {
288     DEFINE_PROP_SIZE("vgamem", BochsDisplayState, vgamem, 16 * 1024 * 1024),
289     DEFINE_PROP_END_OF_LIST(),
290 };
291 
292 static void bochs_display_class_init(ObjectClass *klass, void *data)
293 {
294     DeviceClass *dc = DEVICE_CLASS(klass);
295     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
296 
297     k->class_id  = PCI_CLASS_DISPLAY_OTHER;
298     k->vendor_id = PCI_VENDOR_ID_QEMU;
299     k->device_id = PCI_DEVICE_ID_QEMU_VGA;
300 
301     k->realize   = bochs_display_realize;
302     k->exit      = bochs_display_exit;
303     dc->vmsd     = &vmstate_bochs_display;
304     dc->props    = bochs_display_properties;
305     set_bit(DEVICE_CATEGORY_DISPLAY, dc->categories);
306 }
307 
308 static const TypeInfo bochs_display_type_info = {
309     .name           = TYPE_BOCHS_DISPLAY,
310     .parent         = TYPE_PCI_DEVICE,
311     .instance_size  = sizeof(BochsDisplayState),
312     .instance_init  = bochs_display_init,
313     .class_init     = bochs_display_class_init,
314     .interfaces     = (InterfaceInfo[]) {
315         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
316         { },
317     },
318 };
319 
320 static void bochs_display_register_types(void)
321 {
322     type_register_static(&bochs_display_type_info);
323 }
324 
325 type_init(bochs_display_register_types)
326