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://www.milkymist.org/socdoc/vgafb.pdf
  23  */
  24
  25 #include "hw/hw.h"
  26 #include "hw/sysbus.h"
  27 #include "trace.h"
  28 #include "ui/console.h"
  29 #include "framebuffer.h"
  30 #include "ui/pixel_ops.h"
  31 #include "qemu/error-report.h"
  32
  33 #define BITS 8
  34 #include "milkymist-vgafb_template.h"
  35 #define BITS 15
  36 #include "milkymist-vgafb_template.h"
  37 #define BITS 16
  38 #include "milkymist-vgafb_template.h"
  39 #define BITS 24
  40 #include "milkymist-vgafb_template.h"
  41 #define BITS 32
  42 #include "milkymist-vgafb_template.h"
  43
  44 enum {
  45     R_CTRL = 0,
  46     R_HRES,
  47     R_HSYNC_START,
  48     R_HSYNC_END,
  49     R_HSCAN,
  50     R_VRES,
  51     R_VSYNC_START,
  52     R_VSYNC_END,
  53     R_VSCAN,
  54     R_BASEADDRESS,
  55     R_BASEADDRESS_ACT,
  56     R_BURST_COUNT,
  57     R_DDC,
  58     R_SOURCE_CLOCK,
  59     R_MAX
  60 };
  61
  62 enum {
  63     CTRL_RESET = (1<<0),
  64 };
  65
  66 #define TYPE_MILKYMIST_VGAFB "milkymist-vgafb"
  67 #define MILKYMIST_VGAFB(obj) \
  68     OBJECT_CHECK(MilkymistVgafbState, (obj), TYPE_MILKYMIST_VGAFB)
  69
  70 struct MilkymistVgafbState {
  71     SysBusDevice parent_obj;
  72
  73     MemoryRegion regs_region;
  74     MemoryRegionSection fbsection;
  75     QemuConsole *con;
  76
  77     int invalidate;
  78     uint32_t fb_offset;
  79     uint32_t fb_mask;
  80
  81     uint32_t regs[R_MAX];
  82 };
  83 typedef struct MilkymistVgafbState MilkymistVgafbState;
  84
  85 static int vgafb_enabled(MilkymistVgafbState *s)
  86 {
  87     return !(s->regs[R_CTRL] & CTRL_RESET);
  88 }
  89
  90 static void vgafb_update_display(void *opaque)
  91 {
  92     MilkymistVgafbState *s = opaque;
  93     SysBusDevice *sbd;
  94     DisplaySurface *surface = qemu_console_surface(s->con);
  95     int src_width;
  96     int first = 0;
  97     int last = 0;
  98     drawfn fn;
  99
 100     if (!vgafb_enabled(s)) {
 101         return;
 102     }
 103
 104     sbd = SYS_BUS_DEVICE(s);
 105     int dest_width = s->regs[R_HRES];
 106
 107     switch (surface_bits_per_pixel(surface)) {
 108     case 0:
 109         return;
 110     case 8:
 111         fn = draw_line_8;
 112         break;
 113     case 15:
 114         fn = draw_line_15;
 115         dest_width *= 2;
 116         break;
 117     case 16:
 118         fn = draw_line_16;
 119         dest_width *= 2;
 120         break;
 121     case 24:
 122         fn = draw_line_24;
 123         dest_width *= 3;
 124         break;
 125     case 32:
 126         fn = draw_line_32;
 127         dest_width *= 4;
 128         break;
 129     default:
 130         hw_error("milkymist_vgafb: bad color depth\n");
 131         break;
 132     }
 133
 134     src_width = s->regs[R_HRES] * 2;
 135     if (s->invalidate) {
 136         framebuffer_update_memory_section(&s->fbsection,
 137                                           sysbus_address_space(sbd),
 138                                           s->regs[R_BASEADDRESS] + s->fb_offset,
 139                                           s->regs[R_VRES], src_width);
 140     }
 141
 142     framebuffer_update_display(surface, &s->fbsection,
 143                                s->regs[R_HRES],
 144                                s->regs[R_VRES],
 145                                src_width,
 146                                dest_width,
 147                                0,
 148                                s->invalidate,
 149                                fn,
 150                                NULL,
 151                                &first, &last);
 152
 153     if (first >= 0) {
 154         dpy_gfx_update(s->con, 0, first, s->regs[R_HRES], last - first + 1);
 155     }
 156     s->invalidate = 0;
 157 }
 158
 159 static void vgafb_invalidate_display(void *opaque)
 160 {
 161     MilkymistVgafbState *s = opaque;
 162     s->invalidate = 1;
 163 }
 164
 165 static void vgafb_resize(MilkymistVgafbState *s)
 166 {
 167     if (!vgafb_enabled(s)) {
 168         return;
 169     }
 170
 171     qemu_console_resize(s->con, s->regs[R_HRES], s->regs[R_VRES]);
 172     s->invalidate = 1;
 173 }
 174
 175 static uint64_t vgafb_read(void *opaque, hwaddr addr,
 176                            unsigned size)
 177 {
 178     MilkymistVgafbState *s = opaque;
 179     uint32_t r = 0;
 180
 181     addr >>= 2;
 182     switch (addr) {
 183     case R_CTRL:
 184     case R_HRES:
 185     case R_HSYNC_START:
 186     case R_HSYNC_END:
 187     case R_HSCAN:
 188     case R_VRES:
 189     case R_VSYNC_START:
 190     case R_VSYNC_END:
 191     case R_VSCAN:
 192     case R_BASEADDRESS:
 193     case R_BURST_COUNT:
 194     case R_DDC:
 195     case R_SOURCE_CLOCK:
 196         r = s->regs[addr];
 197     break;
 198     case R_BASEADDRESS_ACT:
 199         r = s->regs[R_BASEADDRESS];
 200     break;
 201
 202     default:
 203         error_report("milkymist_vgafb: read access to unknown register 0x"
 204                 TARGET_FMT_plx, addr << 2);
 205         break;
 206     }
 207
 208     trace_milkymist_vgafb_memory_read(addr << 2, r);
 209
 210     return r;
 211 }
 212
 213 static void vgafb_write(void *opaque, hwaddr addr, uint64_t value,
 214                         unsigned size)
 215 {
 216     MilkymistVgafbState *s = opaque;
 217
 218     trace_milkymist_vgafb_memory_write(addr, value);
 219
 220     addr >>= 2;
 221     switch (addr) {
 222     case R_CTRL:
 223         s->regs[addr] = value;
 224         vgafb_resize(s);
 225         break;
 226     case R_HSYNC_START:
 227     case R_HSYNC_END:
 228     case R_HSCAN:
 229     case R_VSYNC_START:
 230     case R_VSYNC_END:
 231     case R_VSCAN:
 232     case R_BURST_COUNT:
 233     case R_DDC:
 234     case R_SOURCE_CLOCK:
 235         s->regs[addr] = value;
 236         break;
 237     case R_BASEADDRESS:
 238         if (value & 0x1f) {
 239             error_report("milkymist_vgafb: framebuffer base address have to "
 240                      "be 32 byte aligned");
 241             break;
 242         }
 243         s->regs[addr] = value & s->fb_mask;
 244         s->invalidate = 1;
 245         break;
 246     case R_HRES:
 247     case R_VRES:
 248         s->regs[addr] = value;
 249         vgafb_resize(s);
 250         break;
 251     case R_BASEADDRESS_ACT:
 252         error_report("milkymist_vgafb: write to read-only register 0x"
 253                 TARGET_FMT_plx, addr << 2);
 254         break;
 255
 256     default:
 257         error_report("milkymist_vgafb: write access to unknown register 0x"
 258                 TARGET_FMT_plx, addr << 2);
 259         break;
 260     }
 261 }
 262
 263 static const MemoryRegionOps vgafb_mmio_ops = {
 264     .read = vgafb_read,
 265     .write = vgafb_write,
 266     .valid = {
 267         .min_access_size = 4,
 268         .max_access_size = 4,
 269     },
 270     .endianness = DEVICE_NATIVE_ENDIAN,
 271 };
 272
 273 static void milkymist_vgafb_reset(DeviceState *d)
 274 {
 275     MilkymistVgafbState *s = MILKYMIST_VGAFB(d);
 276     int i;
 277
 278     for (i = 0; i < R_MAX; i++) {
 279         s->regs[i] = 0;
 280     }
 281
 282     /* defaults */
 283     s->regs[R_CTRL] = CTRL_RESET;
 284     s->regs[R_HRES] = 640;
 285     s->regs[R_VRES] = 480;
 286     s->regs[R_BASEADDRESS] = 0;
 287 }
 288
 289 static const GraphicHwOps vgafb_ops = {
 290     .invalidate  = vgafb_invalidate_display,
 291     .gfx_update  = vgafb_update_display,
 292 };
 293
 294 static int milkymist_vgafb_init(SysBusDevice *dev)
 295 {
 296     MilkymistVgafbState *s = MILKYMIST_VGAFB(dev);
 297
 298     memory_region_init_io(&s->regs_region, OBJECT(s), &vgafb_mmio_ops, s,
 299             "milkymist-vgafb", R_MAX * 4);
 300     sysbus_init_mmio(dev, &s->regs_region);
 301
 302     s->con = graphic_console_init(DEVICE(dev), 0, &vgafb_ops, s);
 303
 304     return 0;
 305 }
 306
 307 static int vgafb_post_load(void *opaque, int version_id)
 308 {
 309     vgafb_invalidate_display(opaque);
 310     return 0;
 311 }
 312
 313 static const VMStateDescription vmstate_milkymist_vgafb = {
 314     .name = "milkymist-vgafb",
 315     .version_id = 1,
 316     .minimum_version_id = 1,
 317     .post_load = vgafb_post_load,
 318     .fields = (VMStateField[]) {
 319         VMSTATE_UINT32_ARRAY(regs, MilkymistVgafbState, R_MAX),
 320         VMSTATE_END_OF_LIST()
 321     }
 322 };
 323
 324 static Property milkymist_vgafb_properties[] = {
 325     DEFINE_PROP_UINT32("fb_offset", MilkymistVgafbState, fb_offset, 0x0),
 326     DEFINE_PROP_UINT32("fb_mask", MilkymistVgafbState, fb_mask, 0xffffffff),
 327     DEFINE_PROP_END_OF_LIST(),
 328 };
 329
 330 static void milkymist_vgafb_class_init(ObjectClass *klass, void *data)
 331 {
 332     DeviceClass *dc = DEVICE_CLASS(klass);
 333     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 334
 335     k->init = milkymist_vgafb_init;
 336     dc->reset = milkymist_vgafb_reset;
 337     dc->vmsd = &vmstate_milkymist_vgafb;
 338     dc->props = milkymist_vgafb_properties;
 339 }
 340
 341 static const TypeInfo milkymist_vgafb_info = {
 342     .name          = TYPE_MILKYMIST_VGAFB,
 343     .parent        = TYPE_SYS_BUS_DEVICE,
 344     .instance_size = sizeof(MilkymistVgafbState),
 345     .class_init    = milkymist_vgafb_class_init,
 346 };
 347
 348 static void milkymist_vgafb_register_types(void)
 349 {
 350     type_register_static(&milkymist_vgafb_info);
 351 }
 352
 353 type_init(milkymist_vgafb_register_types)