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 #include "qom/object.h"
  36
  37 #define BITS 8
  38 #include "migration/vmstate.h"
  39 #include "milkymist-vgafb_template.h"
  40 #define BITS 15
  41 #include "milkymist-vgafb_template.h"
  42 #define BITS 16
  43 #include "milkymist-vgafb_template.h"
  44 #define BITS 24
  45 #include "milkymist-vgafb_template.h"
  46 #define BITS 32
  47 #include "milkymist-vgafb_template.h"
  48
  49 enum {
  50     R_CTRL = 0,
  51     R_HRES,
  52     R_HSYNC_START,
  53     R_HSYNC_END,
  54     R_HSCAN,
  55     R_VRES,
  56     R_VSYNC_START,
  57     R_VSYNC_END,
  58     R_VSCAN,
  59     R_BASEADDRESS,
  60     R_BASEADDRESS_ACT,
  61     R_BURST_COUNT,
  62     R_DDC,
  63     R_SOURCE_CLOCK,
  64     R_MAX
  65 };
  66
  67 enum {
  68     CTRL_RESET = (1<<0),
  69 };
  70
  71 #define TYPE_MILKYMIST_VGAFB "milkymist-vgafb"
  72 OBJECT_DECLARE_SIMPLE_TYPE(MilkymistVgafbState, 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
  88 static int vgafb_enabled(MilkymistVgafbState *s)
  89 {
  90     return !(s->regs[R_CTRL] & CTRL_RESET);
  91 }
  92
  93 static void vgafb_update_display(void *opaque)
  94 {
  95     MilkymistVgafbState *s = opaque;
  96     SysBusDevice *sbd;
  97     DisplaySurface *surface = qemu_console_surface(s->con);
  98     int src_width;
  99     int first = 0;
 100     int last = 0;
 101     drawfn fn;
 102
 103     if (!vgafb_enabled(s)) {
 104         return;
 105     }
 106
 107     sbd = SYS_BUS_DEVICE(s);
 108     int dest_width = s->regs[R_HRES];
 109
 110     switch (surface_bits_per_pixel(surface)) {
 111     case 0:
 112         return;
 113     case 8:
 114         fn = draw_line_8;
 115         break;
 116     case 15:
 117         fn = draw_line_15;
 118         dest_width *= 2;
 119         break;
 120     case 16:
 121         fn = draw_line_16;
 122         dest_width *= 2;
 123         break;
 124     case 24:
 125         fn = draw_line_24;
 126         dest_width *= 3;
 127         break;
 128     case 32:
 129         fn = draw_line_32;
 130         dest_width *= 4;
 131         break;
 132     default:
 133         hw_error("milkymist_vgafb: bad color depth\n");
 134         break;
 135     }
 136
 137     src_width = s->regs[R_HRES] * 2;
 138     if (s->invalidate) {
 139         framebuffer_update_memory_section(&s->fbsection,
 140                                           sysbus_address_space(sbd),
 141                                           s->regs[R_BASEADDRESS] + s->fb_offset,
 142                                           s->regs[R_VRES], src_width);
 143     }
 144
 145     framebuffer_update_display(surface, &s->fbsection,
 146                                s->regs[R_HRES],
 147                                s->regs[R_VRES],
 148                                src_width,
 149                                dest_width,
 150                                0,
 151                                s->invalidate,
 152                                fn,
 153                                NULL,
 154                                &first, &last);
 155
 156     if (first >= 0) {
 157         dpy_gfx_update(s->con, 0, first, s->regs[R_HRES], last - first + 1);
 158     }
 159     s->invalidate = 0;
 160 }
 161
 162 static void vgafb_invalidate_display(void *opaque)
 163 {
 164     MilkymistVgafbState *s = opaque;
 165     s->invalidate = 1;
 166 }
 167
 168 static void vgafb_resize(MilkymistVgafbState *s)
 169 {
 170     if (!vgafb_enabled(s)) {
 171         return;
 172     }
 173
 174     qemu_console_resize(s->con, s->regs[R_HRES], s->regs[R_VRES]);
 175     s->invalidate = 1;
 176 }
 177
 178 static uint64_t vgafb_read(void *opaque, hwaddr addr,
 179                            unsigned size)
 180 {
 181     MilkymistVgafbState *s = opaque;
 182     uint32_t r = 0;
 183
 184     addr >>= 2;
 185     switch (addr) {
 186     case R_CTRL:
 187     case R_HRES:
 188     case R_HSYNC_START:
 189     case R_HSYNC_END:
 190     case R_HSCAN:
 191     case R_VRES:
 192     case R_VSYNC_START:
 193     case R_VSYNC_END:
 194     case R_VSCAN:
 195     case R_BASEADDRESS:
 196     case R_BURST_COUNT:
 197     case R_DDC:
 198     case R_SOURCE_CLOCK:
 199         r = s->regs[addr];
 200     break;
 201     case R_BASEADDRESS_ACT:
 202         r = s->regs[R_BASEADDRESS];
 203     break;
 204
 205     default:
 206         error_report("milkymist_vgafb: read access to unknown register 0x"
 207                 TARGET_FMT_plx, addr << 2);
 208         break;
 209     }
 210
 211     trace_milkymist_vgafb_memory_read(addr << 2, r);
 212
 213     return r;
 214 }
 215
 216 static void vgafb_write(void *opaque, hwaddr addr, uint64_t value,
 217                         unsigned size)
 218 {
 219     MilkymistVgafbState *s = opaque;
 220
 221     trace_milkymist_vgafb_memory_write(addr, value);
 222
 223     addr >>= 2;
 224     switch (addr) {
 225     case R_CTRL:
 226         s->regs[addr] = value;
 227         vgafb_resize(s);
 228         break;
 229     case R_HSYNC_START:
 230     case R_HSYNC_END:
 231     case R_HSCAN:
 232     case R_VSYNC_START:
 233     case R_VSYNC_END:
 234     case R_VSCAN:
 235     case R_BURST_COUNT:
 236     case R_DDC:
 237     case R_SOURCE_CLOCK:
 238         s->regs[addr] = value;
 239         break;
 240     case R_BASEADDRESS:
 241         if (value & 0x1f) {
 242             error_report("milkymist_vgafb: framebuffer base address have to "
 243                      "be 32 byte aligned");
 244             break;
 245         }
 246         s->regs[addr] = value & s->fb_mask;
 247         s->invalidate = 1;
 248         break;
 249     case R_HRES:
 250     case R_VRES:
 251         s->regs[addr] = value;
 252         vgafb_resize(s);
 253         break;
 254     case R_BASEADDRESS_ACT:
 255         error_report("milkymist_vgafb: write to read-only register 0x"
 256                 TARGET_FMT_plx, addr << 2);
 257         break;
 258
 259     default:
 260         error_report("milkymist_vgafb: write access to unknown register 0x"
 261                 TARGET_FMT_plx, addr << 2);
 262         break;
 263     }
 264 }
 265
 266 static const MemoryRegionOps vgafb_mmio_ops = {
 267     .read = vgafb_read,
 268     .write = vgafb_write,
 269     .valid = {
 270         .min_access_size = 4,
 271         .max_access_size = 4,
 272     },
 273     .endianness = DEVICE_NATIVE_ENDIAN,
 274 };
 275
 276 static void milkymist_vgafb_reset(DeviceState *d)
 277 {
 278     MilkymistVgafbState *s = MILKYMIST_VGAFB(d);
 279     int i;
 280
 281     for (i = 0; i < R_MAX; i++) {
 282         s->regs[i] = 0;
 283     }
 284
 285     /* defaults */
 286     s->regs[R_CTRL] = CTRL_RESET;
 287     s->regs[R_HRES] = 640;
 288     s->regs[R_VRES] = 480;
 289     s->regs[R_BASEADDRESS] = 0;
 290 }
 291
 292 static const GraphicHwOps vgafb_ops = {
 293     .invalidate  = vgafb_invalidate_display,
 294     .gfx_update  = vgafb_update_display,
 295 };
 296
 297 static void milkymist_vgafb_init(Object *obj)
 298 {
 299     MilkymistVgafbState *s = MILKYMIST_VGAFB(obj);
 300     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
 301
 302     memory_region_init_io(&s->regs_region, OBJECT(s), &vgafb_mmio_ops, s,
 303             "milkymist-vgafb", R_MAX * 4);
 304     sysbus_init_mmio(dev, &s->regs_region);
 305 }
 306
 307 static void milkymist_vgafb_realize(DeviceState *dev, Error **errp)
 308 {
 309     MilkymistVgafbState *s = MILKYMIST_VGAFB(dev);
 310
 311     s->con = graphic_console_init(dev, 0, &vgafb_ops, s);
 312 }
 313
 314 static int vgafb_post_load(void *opaque, int version_id)
 315 {
 316     vgafb_invalidate_display(opaque);
 317     return 0;
 318 }
 319
 320 static const VMStateDescription vmstate_milkymist_vgafb = {
 321     .name = "milkymist-vgafb",
 322     .version_id = 1,
 323     .minimum_version_id = 1,
 324     .post_load = vgafb_post_load,
 325     .fields = (VMStateField[]) {
 326         VMSTATE_UINT32_ARRAY(regs, MilkymistVgafbState, R_MAX),
 327         VMSTATE_END_OF_LIST()
 328     }
 329 };
 330
 331 static Property milkymist_vgafb_properties[] = {
 332     DEFINE_PROP_UINT32("fb_offset", MilkymistVgafbState, fb_offset, 0x0),
 333     DEFINE_PROP_UINT32("fb_mask", MilkymistVgafbState, fb_mask, 0xffffffff),
 334     DEFINE_PROP_END_OF_LIST(),
 335 };
 336
 337 static void milkymist_vgafb_class_init(ObjectClass *klass, void *data)
 338 {
 339     DeviceClass *dc = DEVICE_CLASS(klass);
 340
 341     dc->reset = milkymist_vgafb_reset;
 342     dc->vmsd = &vmstate_milkymist_vgafb;
 343     device_class_set_props(dc, milkymist_vgafb_properties);
 344     dc->realize = milkymist_vgafb_realize;
 345 }
 346
 347 static const TypeInfo milkymist_vgafb_info = {
 348     .name          = TYPE_MILKYMIST_VGAFB,
 349     .parent        = TYPE_SYS_BUS_DEVICE,
 350     .instance_size = sizeof(MilkymistVgafbState),
 351     .instance_init = milkymist_vgafb_init,
 352     .class_init    = milkymist_vgafb_class_init,
 353 };
 354
 355 static void milkymist_vgafb_register_types(void)
 356 {
 357     type_register_static(&milkymist_vgafb_info);
 358 }
 359
 360 type_init(milkymist_vgafb_register_types)