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/sysbus.h"
  28 #include "trace.h"
  29 #include "ui/console.h"
  30 #include "framebuffer.h"
  31 #include "ui/pixel_ops.h"
  32 #include "qemu/error-report.h"
  33
  34 #define BITS 8
  35 #include "milkymist-vgafb_template.h"
  36 #define BITS 15
  37 #include "milkymist-vgafb_template.h"
  38 #define BITS 16
  39 #include "milkymist-vgafb_template.h"
  40 #define BITS 24
  41 #include "milkymist-vgafb_template.h"
  42 #define BITS 32
  43 #include "milkymist-vgafb_template.h"
  44
  45 enum {
  46     R_CTRL = 0,
  47     R_HRES,
  48     R_HSYNC_START,
  49     R_HSYNC_END,
  50     R_HSCAN,
  51     R_VRES,
  52     R_VSYNC_START,
  53     R_VSYNC_END,
  54     R_VSCAN,
  55     R_BASEADDRESS,
  56     R_BASEADDRESS_ACT,
  57     R_BURST_COUNT,
  58     R_DDC,
  59     R_SOURCE_CLOCK,
  60     R_MAX
  61 };
  62
  63 enum {
  64     CTRL_RESET = (1<<0),
  65 };
  66
  67 #define TYPE_MILKYMIST_VGAFB "milkymist-vgafb"
  68 #define MILKYMIST_VGAFB(obj) \
  69     OBJECT_CHECK(MilkymistVgafbState, (obj), TYPE_MILKYMIST_VGAFB)
  70
  71 struct MilkymistVgafbState {
  72     SysBusDevice parent_obj;
  73
  74     MemoryRegion regs_region;
  75     MemoryRegionSection fbsection;
  76     QemuConsole *con;
  77
  78     int invalidate;
  79     uint32_t fb_offset;
  80     uint32_t fb_mask;
  81
  82     uint32_t regs[R_MAX];
  83 };
  84 typedef struct MilkymistVgafbState MilkymistVgafbState;
  85
  86 static int vgafb_enabled(MilkymistVgafbState *s)
  87 {
  88     return !(s->regs[R_CTRL] & CTRL_RESET);
  89 }
  90
  91 static void vgafb_update_display(void *opaque)
  92 {
  93     MilkymistVgafbState *s = opaque;
  94     SysBusDevice *sbd;
  95     DisplaySurface *surface = qemu_console_surface(s->con);
  96     int src_width;
  97     int first = 0;
  98     int last = 0;
  99     drawfn fn;
 100
 101     if (!vgafb_enabled(s)) {
 102         return;
 103     }
 104
 105     sbd = SYS_BUS_DEVICE(s);
 106     int dest_width = s->regs[R_HRES];
 107
 108     switch (surface_bits_per_pixel(surface)) {
 109     case 0:
 110         return;
 111     case 8:
 112         fn = draw_line_8;
 113         break;
 114     case 15:
 115         fn = draw_line_15;
 116         dest_width *= 2;
 117         break;
 118     case 16:
 119         fn = draw_line_16;
 120         dest_width *= 2;
 121         break;
 122     case 24:
 123         fn = draw_line_24;
 124         dest_width *= 3;
 125         break;
 126     case 32:
 127         fn = draw_line_32;
 128         dest_width *= 4;
 129         break;
 130     default:
 131         hw_error("milkymist_vgafb: bad color depth\n");
 132         break;
 133     }
 134
 135     src_width = s->regs[R_HRES] * 2;
 136     if (s->invalidate) {
 137         framebuffer_update_memory_section(&s->fbsection,
 138                                           sysbus_address_space(sbd),
 139                                           s->regs[R_BASEADDRESS] + s->fb_offset,
 140                                           s->regs[R_VRES], src_width);
 141     }
 142
 143     framebuffer_update_display(surface, &s->fbsection,
 144                                s->regs[R_HRES],
 145                                s->regs[R_VRES],
 146                                src_width,
 147                                dest_width,
 148                                0,
 149                                s->invalidate,
 150                                fn,
 151                                NULL,
 152                                &first, &last);
 153
 154     if (first >= 0) {
 155         dpy_gfx_update(s->con, 0, first, s->regs[R_HRES], last - first + 1);
 156     }
 157     s->invalidate = 0;
 158 }
 159
 160 static void vgafb_invalidate_display(void *opaque)
 161 {
 162     MilkymistVgafbState *s = opaque;
 163     s->invalidate = 1;
 164 }
 165
 166 static void vgafb_resize(MilkymistVgafbState *s)
 167 {
 168     if (!vgafb_enabled(s)) {
 169         return;
 170     }
 171
 172     qemu_console_resize(s->con, s->regs[R_HRES], s->regs[R_VRES]);
 173     s->invalidate = 1;
 174 }
 175
 176 static uint64_t vgafb_read(void *opaque, hwaddr addr,
 177                            unsigned size)
 178 {
 179     MilkymistVgafbState *s = opaque;
 180     uint32_t r = 0;
 181
 182     addr >>= 2;
 183     switch (addr) {
 184     case R_CTRL:
 185     case R_HRES:
 186     case R_HSYNC_START:
 187     case R_HSYNC_END:
 188     case R_HSCAN:
 189     case R_VRES:
 190     case R_VSYNC_START:
 191     case R_VSYNC_END:
 192     case R_VSCAN:
 193     case R_BASEADDRESS:
 194     case R_BURST_COUNT:
 195     case R_DDC:
 196     case R_SOURCE_CLOCK:
 197         r = s->regs[addr];
 198     break;
 199     case R_BASEADDRESS_ACT:
 200         r = s->regs[R_BASEADDRESS];
 201     break;
 202
 203     default:
 204         error_report("milkymist_vgafb: read access to unknown register 0x"
 205                 TARGET_FMT_plx, addr << 2);
 206         break;
 207     }
 208
 209     trace_milkymist_vgafb_memory_read(addr << 2, r);
 210
 211     return r;
 212 }
 213
 214 static void vgafb_write(void *opaque, hwaddr addr, uint64_t value,
 215                         unsigned size)
 216 {
 217     MilkymistVgafbState *s = opaque;
 218
 219     trace_milkymist_vgafb_memory_write(addr, value);
 220
 221     addr >>= 2;
 222     switch (addr) {
 223     case R_CTRL:
 224         s->regs[addr] = value;
 225         vgafb_resize(s);
 226         break;
 227     case R_HSYNC_START:
 228     case R_HSYNC_END:
 229     case R_HSCAN:
 230     case R_VSYNC_START:
 231     case R_VSYNC_END:
 232     case R_VSCAN:
 233     case R_BURST_COUNT:
 234     case R_DDC:
 235     case R_SOURCE_CLOCK:
 236         s->regs[addr] = value;
 237         break;
 238     case R_BASEADDRESS:
 239         if (value & 0x1f) {
 240             error_report("milkymist_vgafb: framebuffer base address have to "
 241                      "be 32 byte aligned");
 242             break;
 243         }
 244         s->regs[addr] = value & s->fb_mask;
 245         s->invalidate = 1;
 246         break;
 247     case R_HRES:
 248     case R_VRES:
 249         s->regs[addr] = value;
 250         vgafb_resize(s);
 251         break;
 252     case R_BASEADDRESS_ACT:
 253         error_report("milkymist_vgafb: write to read-only register 0x"
 254                 TARGET_FMT_plx, addr << 2);
 255         break;
 256
 257     default:
 258         error_report("milkymist_vgafb: write access to unknown register 0x"
 259                 TARGET_FMT_plx, addr << 2);
 260         break;
 261     }
 262 }
 263
 264 static const MemoryRegionOps vgafb_mmio_ops = {
 265     .read = vgafb_read,
 266     .write = vgafb_write,
 267     .valid = {
 268         .min_access_size = 4,
 269         .max_access_size = 4,
 270     },
 271     .endianness = DEVICE_NATIVE_ENDIAN,
 272 };
 273
 274 static void milkymist_vgafb_reset(DeviceState *d)
 275 {
 276     MilkymistVgafbState *s = MILKYMIST_VGAFB(d);
 277     int i;
 278
 279     for (i = 0; i < R_MAX; i++) {
 280         s->regs[i] = 0;
 281     }
 282
 283     /* defaults */
 284     s->regs[R_CTRL] = CTRL_RESET;
 285     s->regs[R_HRES] = 640;
 286     s->regs[R_VRES] = 480;
 287     s->regs[R_BASEADDRESS] = 0;
 288 }
 289
 290 static const GraphicHwOps vgafb_ops = {
 291     .invalidate  = vgafb_invalidate_display,
 292     .gfx_update  = vgafb_update_display,
 293 };
 294
 295 static void milkymist_vgafb_init(Object *obj)
 296 {
 297     MilkymistVgafbState *s = MILKYMIST_VGAFB(obj);
 298     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
 299
 300     memory_region_init_io(&s->regs_region, OBJECT(s), &vgafb_mmio_ops, s,
 301             "milkymist-vgafb", R_MAX * 4);
 302     sysbus_init_mmio(dev, &s->regs_region);
 303 }
 304
 305 static void milkymist_vgafb_realize(DeviceState *dev, Error **errp)
 306 {
 307     MilkymistVgafbState *s = MILKYMIST_VGAFB(dev);
 308
 309     s->con = graphic_console_init(dev, 0, &vgafb_ops, s);
 310 }
 311
 312 static int vgafb_post_load(void *opaque, int version_id)
 313 {
 314     vgafb_invalidate_display(opaque);
 315     return 0;
 316 }
 317
 318 static const VMStateDescription vmstate_milkymist_vgafb = {
 319     .name = "milkymist-vgafb",
 320     .version_id = 1,
 321     .minimum_version_id = 1,
 322     .post_load = vgafb_post_load,
 323     .fields = (VMStateField[]) {
 324         VMSTATE_UINT32_ARRAY(regs, MilkymistVgafbState, R_MAX),
 325         VMSTATE_END_OF_LIST()
 326     }
 327 };
 328
 329 static Property milkymist_vgafb_properties[] = {
 330     DEFINE_PROP_UINT32("fb_offset", MilkymistVgafbState, fb_offset, 0x0),
 331     DEFINE_PROP_UINT32("fb_mask", MilkymistVgafbState, fb_mask, 0xffffffff),
 332     DEFINE_PROP_END_OF_LIST(),
 333 };
 334
 335 static void milkymist_vgafb_class_init(ObjectClass *klass, void *data)
 336 {
 337     DeviceClass *dc = DEVICE_CLASS(klass);
 338
 339     dc->reset = milkymist_vgafb_reset;
 340     dc->vmsd = &vmstate_milkymist_vgafb;
 341     dc->props = milkymist_vgafb_properties;
 342     dc->realize = milkymist_vgafb_realize;
 343 }
 344
 345 static const TypeInfo milkymist_vgafb_info = {
 346     .name          = TYPE_MILKYMIST_VGAFB,
 347     .parent        = TYPE_SYS_BUS_DEVICE,
 348     .instance_size = sizeof(MilkymistVgafbState),
 349     .instance_init = milkymist_vgafb_init,
 350     .class_init    = milkymist_vgafb_class_init,
 351 };
 352
 353 static void milkymist_vgafb_register_types(void)
 354 {
 355     type_register_static(&milkymist_vgafb_info);
 356 }
 357
 358 type_init(milkymist_vgafb_register_types)