hw/display/milkymist-vgafb.c

   1
   2 /*
   3  *  QEMU model of the Milkymist VGA framebuffer.
   4  *
   5  *  Copyright (c) 2010-2012 Michael Walle <michael@walle.cc>
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  19  *
  20  *
  21  * Specification available at:
  22  *   http://milkymist.walle.cc/socdoc/vgafb.pdf
  23  */
  24
  25 #include "qemu/osdep.h"
  26 #include "hw/hw.h"
  27 #include "hw/qdev-properties.h"
  28 #include "hw/sysbus.h"
  29 #include "trace.h"
  30 #include "ui/console.h"
  31 #include "framebuffer.h"
  32 #include "ui/pixel_ops.h"
  33 #include "qemu/error-report.h"
  34 #include "qemu/module.h"
  35
  36 #define BITS 8
  37 #include "migration/vmstate.h"
  38 #include "milkymist-vgafb_template.h"
  39 #define BITS 15
  40 #include "milkymist-vgafb_template.h"
  41 #define BITS 16
  42 #include "milkymist-vgafb_template.h"
  43 #define BITS 24
  44 #include "milkymist-vgafb_template.h"
  45 #define BITS 32
  46 #include "milkymist-vgafb_template.h"
  47
  48 enum {
  49     R_CTRL = 0,
  50     R_HRES,
  51     R_HSYNC_START,
  52     R_HSYNC_END,
  53     R_HSCAN,
  54     R_VRES,
  55     R_VSYNC_START,
  56     R_VSYNC_END,
  57     R_VSCAN,
  58     R_BASEADDRESS,
  59     R_BASEADDRESS_ACT,
  60     R_BURST_COUNT,
  61     R_DDC,
  62     R_SOURCE_CLOCK,
  63     R_MAX
  64 };
  65
  66 enum {
  67     CTRL_RESET = (1<<0),
  68 };
  69
  70 #define TYPE_MILKYMIST_VGAFB "milkymist-vgafb"
  71 #define MILKYMIST_VGAFB(obj) \
  72     OBJECT_CHECK(MilkymistVgafbState, (obj), TYPE_MILKYMIST_VGAFB)
  73
  74 struct MilkymistVgafbState {
  75     SysBusDevice parent_obj;
  76
  77     MemoryRegion regs_region;
  78     MemoryRegionSection fbsection;
  79     QemuConsole *con;
  80
  81     int invalidate;
  82     uint32_t fb_offset;
  83     uint32_t fb_mask;
  84
  85     uint32_t regs[R_MAX];
  86 };
  87 typedef struct MilkymistVgafbState MilkymistVgafbState;
  88
  89 static int vgafb_enabled(MilkymistVgafbState *s)
  90 {
  91     return !(s->regs[R_CTRL] & CTRL_RESET);
  92 }
  93
  94 static void vgafb_update_display(void *opaque)
  95 {
  96     MilkymistVgafbState *s = opaque;
  97     SysBusDevice *sbd;
  98     DisplaySurface *surface = qemu_console_surface(s->con);
  99     int src_width;
 100     int first = 0;
 101     int last = 0;
 102     drawfn fn;
 103
 104     if (!vgafb_enabled(s)) {
 105         return;
 106     }
 107
 108     sbd = SYS_BUS_DEVICE(s);
 109     int dest_width = s->regs[R_HRES];
 110
 111     switch (surface_bits_per_pixel(surface)) {
 112     case 0:
 113         return;
 114     case 8:
 115         fn = draw_line_8;
 116         break;
 117     case 15:
 118         fn = draw_line_15;
 119         dest_width *= 2;
 120         break;
 121     case 16:
 122         fn = draw_line_16;
 123         dest_width *= 2;
 124         break;
 125     case 24:
 126         fn = draw_line_24;
 127         dest_width *= 3;
 128         break;
 129     case 32:
 130         fn = draw_line_32;
 131         dest_width *= 4;
 132         break;
 133     default:
 134         hw_error("milkymist_vgafb: bad color depth\n");
 135         break;
 136     }
 137
 138     src_width = s->regs[R_HRES] * 2;
 139     if (s->invalidate) {
 140         framebuffer_update_memory_section(&s->fbsection,
 141                                           sysbus_address_space(sbd),
 142                                           s->regs[R_BASEADDRESS] + s->fb_offset,
 143                                           s->regs[R_VRES], src_width);
 144     }
 145
 146     framebuffer_update_display(surface, &s->fbsection,
 147                                s->regs[R_HRES],
 148                                s->regs[R_VRES],
 149                                src_width,
 150                                dest_width,
 151                                0,
 152                                s->invalidate,
 153                                fn,
 154                                NULL,
 155                                &first, &last);
 156
 157     if (first >= 0) {
 158         dpy_gfx_update(s->con, 0, first, s->regs[R_HRES], last - first + 1);
 159     }
 160     s->invalidate = 0;
 161 }
 162
 163 static void vgafb_invalidate_display(void *opaque)
 164 {
 165     MilkymistVgafbState *s = opaque;
 166     s->invalidate = 1;
 167 }
 168
 169 static void vgafb_resize(MilkymistVgafbState *s)
 170 {
 171     if (!vgafb_enabled(s)) {
 172         return;
 173     }
 174
 175     qemu_console_resize(s->con, s->regs[R_HRES], s->regs[R_VRES]);
 176     s->invalidate = 1;
 177 }
 178
 179 static uint64_t vgafb_read(void *opaque, hwaddr addr,
 180                            unsigned size)
 181 {
 182     MilkymistVgafbState *s = opaque;
 183     uint32_t r = 0;
 184
 185     addr >>= 2;
 186     switch (addr) {
 187     case R_CTRL:
 188     case R_HRES:
 189     case R_HSYNC_START:
 190     case R_HSYNC_END:
 191     case R_HSCAN:
 192     case R_VRES:
 193     case R_VSYNC_START:
 194     case R_VSYNC_END:
 195     case R_VSCAN:
 196     case R_BASEADDRESS:
 197     case R_BURST_COUNT:
 198     case R_DDC:
 199     case R_SOURCE_CLOCK:
 200         r = s->regs[addr];
 201     break;
 202     case R_BASEADDRESS_ACT:
 203         r = s->regs[R_BASEADDRESS];
 204     break;
 205
 206     default:
 207         error_report("milkymist_vgafb: read access to unknown register 0x"
 208                 TARGET_FMT_plx, addr << 2);
 209         break;
 210     }
 211
 212     trace_milkymist_vgafb_memory_read(addr << 2, r);
 213
 214     return r;
 215 }
 216
 217 static void vgafb_write(void *opaque, hwaddr addr, uint64_t value,
 218                         unsigned size)
 219 {
 220     MilkymistVgafbState *s = opaque;
 221
 222     trace_milkymist_vgafb_memory_write(addr, value);
 223
 224     addr >>= 2;
 225     switch (addr) {
 226     case R_CTRL:
 227         s->regs[addr] = value;
 228         vgafb_resize(s);
 229         break;
 230     case R_HSYNC_START:
 231     case R_HSYNC_END:
 232     case R_HSCAN:
 233     case R_VSYNC_START:
 234     case R_VSYNC_END:
 235     case R_VSCAN:
 236     case R_BURST_COUNT:
 237     case R_DDC:
 238     case R_SOURCE_CLOCK:
 239         s->regs[addr] = value;
 240         break;
 241     case R_BASEADDRESS:
 242         if (value & 0x1f) {
 243             error_report("milkymist_vgafb: framebuffer base address have to "
 244                      "be 32 byte aligned");
 245             break;
 246         }
 247         s->regs[addr] = value & s->fb_mask;
 248         s->invalidate = 1;
 249         break;
 250     case R_HRES:
 251     case R_VRES:
 252         s->regs[addr] = value;
 253         vgafb_resize(s);
 254         break;
 255     case R_BASEADDRESS_ACT:
 256         error_report("milkymist_vgafb: write to read-only register 0x"
 257                 TARGET_FMT_plx, addr << 2);
 258         break;
 259
 260     default:
 261         error_report("milkymist_vgafb: write access to unknown register 0x"
 262                 TARGET_FMT_plx, addr << 2);
 263         break;
 264     }
 265 }
 266
 267 static const MemoryRegionOps vgafb_mmio_ops = {
 268     .read = vgafb_read,
 269     .write = vgafb_write,
 270     .valid = {
 271         .min_access_size = 4,
 272         .max_access_size = 4,
 273     },
 274     .endianness = DEVICE_NATIVE_ENDIAN,
 275 };
 276
 277 static void milkymist_vgafb_reset(DeviceState *d)
 278 {
 279     MilkymistVgafbState *s = MILKYMIST_VGAFB(d);
 280     int i;
 281
 282     for (i = 0; i < R_MAX; i++) {
 283         s->regs[i] = 0;
 284     }
 285
 286     /* defaults */
 287     s->regs[R_CTRL] = CTRL_RESET;
 288     s->regs[R_HRES] = 640;
 289     s->regs[R_VRES] = 480;
 290     s->regs[R_BASEADDRESS] = 0;
 291 }
 292
 293 static const GraphicHwOps vgafb_ops = {
 294     .invalidate  = vgafb_invalidate_display,
 295     .gfx_update  = vgafb_update_display,
 296 };
 297
 298 static void milkymist_vgafb_init(Object *obj)
 299 {
 300     MilkymistVgafbState *s = MILKYMIST_VGAFB(obj);
 301     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
 302
 303     memory_region_init_io(&s->regs_region, OBJECT(s), &vgafb_mmio_ops, s,
 304             "milkymist-vgafb", R_MAX * 4);
 305     sysbus_init_mmio(dev, &s->regs_region);
 306 }
 307
 308 static void milkymist_vgafb_realize(DeviceState *dev, Error **errp)
 309 {
 310     MilkymistVgafbState *s = MILKYMIST_VGAFB(dev);
 311
 312     s->con = graphic_console_init(dev, 0, &vgafb_ops, s);
 313 }
 314
 315 static int vgafb_post_load(void *opaque, int version_id)
 316 {
 317     vgafb_invalidate_display(opaque);
 318     return 0;
 319 }
 320
 321 static const VMStateDescription vmstate_milkymist_vgafb = {
 322     .name = "milkymist-vgafb",
 323     .version_id = 1,
 324     .minimum_version_id = 1,
 325     .post_load = vgafb_post_load,
 326     .fields = (VMStateField[]) {
 327         VMSTATE_UINT32_ARRAY(regs, MilkymistVgafbState, R_MAX),
 328         VMSTATE_END_OF_LIST()
 329     }
 330 };
 331
 332 static Property milkymist_vgafb_properties[] = {
 333     DEFINE_PROP_UINT32("fb_offset", MilkymistVgafbState, fb_offset, 0x0),
 334     DEFINE_PROP_UINT32("fb_mask", MilkymistVgafbState, fb_mask, 0xffffffff),
 335     DEFINE_PROP_END_OF_LIST(),
 336 };
 337
 338 static void milkymist_vgafb_class_init(ObjectClass *klass, void *data)
 339 {
 340     DeviceClass *dc = DEVICE_CLASS(klass);
 341
 342     dc->reset = milkymist_vgafb_reset;
 343     dc->vmsd = &vmstate_milkymist_vgafb;
 344     dc->props = milkymist_vgafb_properties;
 345     dc->realize = milkymist_vgafb_realize;
 346 }
 347
 348 static const TypeInfo milkymist_vgafb_info = {
 349     .name          = TYPE_MILKYMIST_VGAFB,
 350     .parent        = TYPE_SYS_BUS_DEVICE,
 351     .instance_size = sizeof(MilkymistVgafbState),
 352     .instance_init = milkymist_vgafb_init,
 353     .class_init    = milkymist_vgafb_class_init,
 354 };
 355
 356 static void milkymist_vgafb_register_types(void)
 357 {
 358     type_register_static(&milkymist_vgafb_info);
 359 }
 360
 361 type_init(milkymist_vgafb_register_types)