xref: /openbmc/qemu/hw/display/bochs-display.c (revision 429d3ae2)
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         break;
162     case 32:
163         mode->format = s->big_endian_fb
164             ? PIXMAN_BE_x8r8g8b8
165             : PIXMAN_LE_x8r8g8b8;
166         mode->bytepp = 4;
167         break;
168     default:
169         return -1;
170     }
171 
172     mode->width  = vbe[VBE_DISPI_INDEX_XRES];
173     mode->height = vbe[VBE_DISPI_INDEX_YRES];
174     virt_width  = vbe[VBE_DISPI_INDEX_VIRT_WIDTH];
175     if (virt_width < mode->width) {
176         virt_width = mode->width;
177     }
178     mode->stride = virt_width * mode->bytepp;
179     mode->size   = (uint64_t)mode->stride * mode->height;
180     mode->offset = ((uint64_t)vbe[VBE_DISPI_INDEX_X_OFFSET] * mode->bytepp +
181                     (uint64_t)vbe[VBE_DISPI_INDEX_Y_OFFSET] * mode->stride);
182 
183     if (mode->width < 64 || mode->height < 64) {
184         return -1;
185     }
186     if (mode->offset + mode->size > s->vgamem) {
187         return -1;
188     }
189     return 0;
190 }
191 
192 static void bochs_display_update(void *opaque)
193 {
194     BochsDisplayState *s = opaque;
195     DirtyBitmapSnapshot *snap = NULL;
196     bool full_update = false;
197     BochsDisplayMode mode;
198     DisplaySurface *ds;
199     uint8_t *ptr;
200     bool dirty;
201     int y, ys, ret;
202 
203     ret = bochs_display_get_mode(s, &mode);
204     if (ret < 0) {
205         /* no (valid) video mode */
206         return;
207     }
208 
209     if (memcmp(&s->mode, &mode, sizeof(mode)) != 0) {
210         /* video mode switch */
211         s->mode = mode;
212         ptr = memory_region_get_ram_ptr(&s->vram);
213         ds = qemu_create_displaysurface_from(mode.width,
214                                              mode.height,
215                                              mode.format,
216                                              mode.stride,
217                                              ptr + mode.offset);
218         dpy_gfx_replace_surface(s->con, ds);
219         full_update = true;
220     }
221 
222     if (full_update) {
223         dpy_gfx_update_full(s->con);
224     } else {
225         snap = memory_region_snapshot_and_clear_dirty(&s->vram,
226                                                       mode.offset, mode.size,
227                                                       DIRTY_MEMORY_VGA);
228         ys = -1;
229         for (y = 0; y < mode.height; y++) {
230             dirty = memory_region_snapshot_get_dirty(&s->vram, snap,
231                                                      mode.offset + mode.stride * y,
232                                                      mode.stride);
233             if (dirty && ys < 0) {
234                 ys = y;
235             }
236             if (!dirty && ys >= 0) {
237                 dpy_gfx_update(s->con, 0, ys,
238                                mode.width, y - ys);
239                 ys = -1;
240             }
241         }
242         if (ys >= 0) {
243             dpy_gfx_update(s->con, 0, ys,
244                            mode.width, y - ys);
245         }
246     }
247 }
248 
249 static const GraphicHwOps bochs_display_gfx_ops = {
250     .gfx_update = bochs_display_update,
251 };
252 
253 static void bochs_display_realize(PCIDevice *dev, Error **errp)
254 {
255     BochsDisplayState *s = BOCHS_DISPLAY(dev);
256     Object *obj = OBJECT(dev);
257     int ret;
258 
259     s->con = graphic_console_init(DEVICE(dev), 0, &bochs_display_gfx_ops, s);
260 
261     if (s->vgamem < (4 * 1024 * 1024)) {
262         error_setg(errp, "bochs-display: video memory too small");
263     }
264     if (s->vgamem > (256 * 1024 * 1024)) {
265         error_setg(errp, "bochs-display: video memory too big");
266     }
267     s->vgamem = pow2ceil(s->vgamem);
268 
269     memory_region_init_ram(&s->vram, obj, "bochs-display-vram", s->vgamem,
270                            &error_fatal);
271     memory_region_init_io(&s->vbe, obj, &bochs_display_vbe_ops, s,
272                           "bochs dispi interface", PCI_VGA_BOCHS_SIZE);
273     memory_region_init_io(&s->qext, obj, &bochs_display_qext_ops, s,
274                           "qemu extended regs", PCI_VGA_QEXT_SIZE);
275 
276     memory_region_init(&s->mmio, obj, "bochs-display-mmio",
277                        PCI_VGA_MMIO_SIZE);
278     memory_region_add_subregion(&s->mmio, PCI_VGA_BOCHS_OFFSET, &s->vbe);
279     memory_region_add_subregion(&s->mmio, PCI_VGA_QEXT_OFFSET, &s->qext);
280 
281     pci_set_byte(&s->pci.config[PCI_REVISION_ID], 2);
282     pci_register_bar(&s->pci, 0, PCI_BASE_ADDRESS_MEM_PREFETCH, &s->vram);
283     pci_register_bar(&s->pci, 2, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->mmio);
284 
285     if (pci_bus_is_express(pci_get_bus(dev))) {
286         dev->cap_present |= QEMU_PCI_CAP_EXPRESS;
287         ret = pcie_endpoint_cap_init(dev, 0x80);
288         assert(ret > 0);
289     }
290 
291     memory_region_set_log(&s->vram, true, DIRTY_MEMORY_VGA);
292 }
293 
294 static bool bochs_display_get_big_endian_fb(Object *obj, Error **errp)
295 {
296     BochsDisplayState *s = BOCHS_DISPLAY(obj);
297 
298     return s->big_endian_fb;
299 }
300 
301 static void bochs_display_set_big_endian_fb(Object *obj, bool value,
302                                             Error **errp)
303 {
304     BochsDisplayState *s = BOCHS_DISPLAY(obj);
305 
306     s->big_endian_fb = value;
307 }
308 
309 static void bochs_display_init(Object *obj)
310 {
311     /* Expose framebuffer byteorder via QOM */
312     object_property_add_bool(obj, "big-endian-framebuffer",
313                              bochs_display_get_big_endian_fb,
314                              bochs_display_set_big_endian_fb,
315                              NULL);
316 }
317 
318 static void bochs_display_exit(PCIDevice *dev)
319 {
320     BochsDisplayState *s = BOCHS_DISPLAY(dev);
321 
322     graphic_console_close(s->con);
323 }
324 
325 static Property bochs_display_properties[] = {
326     DEFINE_PROP_SIZE("vgamem", BochsDisplayState, vgamem, 16 * 1024 * 1024),
327     DEFINE_PROP_END_OF_LIST(),
328 };
329 
330 static void bochs_display_class_init(ObjectClass *klass, void *data)
331 {
332     DeviceClass *dc = DEVICE_CLASS(klass);
333     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
334 
335     k->class_id  = PCI_CLASS_DISPLAY_OTHER;
336     k->vendor_id = PCI_VENDOR_ID_QEMU;
337     k->device_id = PCI_DEVICE_ID_QEMU_VGA;
338 
339     k->realize   = bochs_display_realize;
340     k->exit      = bochs_display_exit;
341     dc->vmsd     = &vmstate_bochs_display;
342     dc->props    = bochs_display_properties;
343     set_bit(DEVICE_CATEGORY_DISPLAY, dc->categories);
344 }
345 
346 static const TypeInfo bochs_display_type_info = {
347     .name           = TYPE_BOCHS_DISPLAY,
348     .parent         = TYPE_PCI_DEVICE,
349     .instance_size  = sizeof(BochsDisplayState),
350     .instance_init  = bochs_display_init,
351     .class_init     = bochs_display_class_init,
352     .interfaces     = (InterfaceInfo[]) {
353         { INTERFACE_PCIE_DEVICE },
354         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
355         { },
356     },
357 };
358 
359 static void bochs_display_register_types(void)
360 {
361     type_register_static(&bochs_display_type_info);
362 }
363 
364 type_init(bochs_display_register_types)
365