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   1 #ifndef VDP_H_
   2 #define VDP_H_
   3
   4 #include <stdint.h>
   5
   6 #define VDP_PORT_DATA           *((volatile uint16_t*)0xc00000)
   7 #define VDP_PORT_DATA32         *((volatile uint32_t*)0xc00000)
   8 #define VDP_PORT_CTL            *((volatile uint16_t*)0xc00004)
   9 #define VDP_PORT_CTL32          *((volatile uint32_t*)0xc00004)
  10 #define VDP_PORT_HVCNT          *((volatile uint16_t*)0xc00008)
  11 #define VDP_PORT_PSG            *((volatile uint16_t*)0xc00010)
  12
  13 #define VDP_PORT_STATUS         *((volatile uint16_t*)0xc00004)
  14
  15 enum {
  16         VDP_REG_MODE1                   = 0,
  17         VDP_REG_MODE2                   = 1,
  18         VDP_REG_NAMETAB_A               = 2,
  19         VDP_REG_NAMETAB_WIN             = 3,
  20         VDP_REG_NAMETAB_B               = 4,
  21         VDP_REG_SPRITE_TAB              = 5,
  22         VDP_REG_BGCOL                   = 7,
  23         VDP_REG_HINTR                   = 10,
  24         VDP_REG_MODE3                   = 11,
  25         VDP_REG_MODE4                   = 12,
  26         VDP_REG_SCROLL_TAB              = 13,
  27         VDP_REG_AUTOINC                 = 15,
  28         VDP_REG_SCROLL_SIZE             = 16,
  29         VDP_REG_WIN_XPOS                = 17,
  30         VDP_REG_WIN_YPOS                = 18,
  31         VDP_REG_DMA_LEN_LOW             = 19,
  32         VDP_REG_DMA_LEN_HIGH    = 20,
  33         VDP_REG_DMA_SRC_LOW             = 21,
  34         VDP_REG_DMA_SRC_MID             = 22,
  35         VDP_REG_DMA_SRC_HIGH    = 23,
  36
  37         VDP_NUM_REGS
  38 };
  39
  40 uint16_t vdp_reg_shadow[VDP_NUM_REGS];
  41
  42 /* access VDP memory */
  43 enum { VDP_MEM_READ, VDP_MEM_WRITE };
  44 enum {
  45         VDP_MEM_VRAM    = 0,
  46         VDP_MEM_CRAM    = 0xa,  /* CD5->CD0: 0 0 r 0 w 0 */
  47         VDP_MEM_VSRAM   = 4             /* CD5->CD0: 0 0 0 1 0 0 */
  48 };
  49
  50 enum {
  51         VDP_PLANE_A,
  52         VDP_PLANE_B,
  53         VDP_PLANE_WIN
  54 };
  55
  56 enum {
  57         VDP_TILE_LOW_PRIO       = 0,
  58         VDP_TILE_HFLIP          = 0x0800,
  59         VDP_TILE_VFLIP          = 0x1000,
  60         VDP_TILE_HIGH_PRIO      = 0x8000
  61 };
  62
  63 enum {
  64         VDP_STAT_PAL            = 0x0001,
  65         VDP_STAT_DMABUSY        = 0x0002,
  66         VDP_STAT_HBLANK         = 0x0004,
  67         VDP_STAT_VBLANK         = 0x0008,
  68         VDP_STAT_ODDFIELD       = 0x0010,
  69         VDP_STAT_SPRITE_COL     = 0x0020,
  70         VDP_STAT_SPRITE_OVF = 0x0040,
  71         VDP_STAT_VINTR          = 0x0080,
  72         VDP_STAT_FIFO_FULL      = 0x0100,
  73         VDP_STAT_FIFO_EMPTY     = 0x0200
  74 };
  75
  76
  77 static inline void vdp_setup_access(uint16_t addr, int rw, int memid)
  78 {
  79         uint32_t type;
  80         if(rw == VDP_MEM_WRITE) {
  81                 type = (memid & 7) | 1;
  82         } else {
  83                 type = memid & 0xc;
  84         }
  85
  86         VDP_PORT_CTL32 = (((uint32_t)addr & 0x3fff) << 16) | ((addr >> 14) & 3) |
  87                 ((type << 2) & 0xf0) | (type << 30);
  88 }
  89
  90
  91 /* mode register 1 */
  92 enum {
  93         VDP_MODE1_BASE  = 0x4,
  94         VDP_MODE1_HVCNT = 0x2,
  95         VDP_MODE1_HINTR = 0x10
  96 };
  97
  98 /* mode register 2 */
  99 enum {
 100         VDP_MODE2_BASE          = 0x4,
 101         VDP_MODE2_V30CELL       = 0x8,
 102         VDP_MODE2_DMA           = 0x10,
 103         VDP_MODE2_VINTR         = 0x20,
 104         VDP_MODE2_DISP          = 0x40
 105 };
 106
 107 /* mode register 3 */
 108 enum {
 109         VDP_MODE3_BASE                  = 0,
 110         VDP_MODE3_HSCROLL_CELL  = 2,
 111         VDP_MODE3_HSCROLL_LINE  = 3,
 112         VDP_MODE3_VSCROLL_2CELL = 4,
 113         VDP_MODE3_EXTINTR               = 8
 114 };
 115
 116 /* mode register 4 */
 117 enum {
 118         VDP_MODE4_BASE                  = 0,
 119         VDP_MODE4_H40CELL               = 0x81,
 120         VDP_MODE4_ILACE                 = 2,
 121         VDP_MODE4_ILACE_2XRES   = 6,
 122         VDP_MODE4_SH                    = 8     /* shadow/highlight enable */
 123 };
 124
 125 /* scroll size register */
 126 enum {
 127         VDP_SCROLL_H32          = 0,
 128         VDP_SCROLL_H64          = 1,
 129         VDP_SCROLL_H128         = 3,
 130         VDP_SCROLL_V32          = 0,
 131         VDP_SCROLL_V64          = 0x10,
 132         VDP_SCROLL_V128         = 0x30
 133 };
 134
 135 /* window X/Y position register */
 136 enum {
 137         VDP_WIN_LEFT    = 0,
 138         VDP_WIN_UP              = 0,
 139         VDP_WIN_RIGHT   = 0x80,
 140         VDP_WIN_DOWN    = 0x80,
 141         VDP_WIN_POSMASK = 0x1f
 142 };
 143
 144 #define VDP_PACK_RGB(r, g, b)   \
 145         ((((uint16_t)(r) & 7) << 1) | (((uint16_t)(g) & 7) << 5) | (((uint16_t)(b) & 7) << 9))
 146
 147
 148 static inline void vdp_setreg(int reg, uint8_t value)
 149 {
 150         vdp_reg_shadow[reg] = value;
 151         VDP_PORT_CTL = (uint16_t)value | (reg << 8) | (uint16_t)0x8000;
 152 }
 153
 154 static inline uint16_t vdp_getreg(int reg)
 155 {
 156         return vdp_reg_shadow[reg];
 157 }
 158
 159 static inline uint16_t vdp_status(void)
 160 {
 161         return VDP_PORT_CTL;
 162 }
 163
 164 static inline void vdp_set_bgcolor(int palidx, int colidx)
 165 {
 166         vdp_setreg(VDP_REG_BGCOL, (colidx & 0xf) | (palidx << 4));
 167 }
 168
 169 static inline void vdp_set_autoinc(int stride)
 170 {
 171         vdp_setreg(VDP_REG_AUTOINC, stride);
 172 }
 173
 174 static inline void vdp_begin_palette(int pidx, int cidx)
 175 {
 176         uint16_t paddr = (pidx << 5) | (cidx << 1);
 177         vdp_setup_access(paddr, VDP_MEM_WRITE, VDP_MEM_CRAM);
 178 }
 179
 180 static inline void vdp_set_pal_entry(int pidx, int cidx, int r, int g, int b)
 181 {
 182         vdp_begin_palette(pidx, cidx);
 183         VDP_PORT_DATA = VDP_PACK_RGB(r, g, b);
 184 }
 185
 186 static inline void vdp_enable_vintr(void)
 187 {
 188         vdp_setreg(VDP_REG_MODE2, vdp_getreg(VDP_REG_MODE2) | VDP_MODE2_VINTR);
 189 }
 190
 191 static inline void vdp_disable_vintr(void)
 192 {
 193         vdp_setreg(VDP_REG_MODE2, vdp_getreg(VDP_REG_MODE2) & ~VDP_MODE2_VINTR);
 194 }
 195
 196 static inline void vdp_enable_hintr(int counter)
 197 {
 198         vdp_setreg(VDP_REG_HINTR, counter);
 199         vdp_setreg(VDP_REG_MODE1, vdp_getreg(VDP_REG_MODE1) | VDP_MODE1_HINTR);
 200 }
 201
 202 static inline void vdp_disable_hintr(void)
 203 {
 204         vdp_setreg(VDP_REG_MODE1, vdp_getreg(VDP_REG_MODE1) & ~VDP_MODE1_HINTR);
 205 }
 206
 207 static inline void vdp_set_nametab_addr(int plane, uint16_t addr)
 208 {
 209         switch(plane) {
 210         case VDP_PLANE_A:
 211                 vdp_setreg(VDP_REG_NAMETAB_A, (addr >> 10) & 0x38);
 212                 break;
 213         case VDP_PLANE_B:
 214                 vdp_setreg(VDP_REG_NAMETAB_B, (addr >> 13) & 7);
 215                 break;
 216         case VDP_PLANE_WIN:
 217                 vdp_setreg(VDP_REG_NAMETAB_WIN, (addr >> 10) & 0x7e);
 218         default:
 219                 break;
 220         }
 221 }
 222
 223 static inline uint16_t vdp_nametab_addr(int idx)
 224 {
 225         return (uint16_t)idx << 13;
 226 }
 227
 228 static inline void vdp_set_nametab_idx(int plane, int idx)
 229 {
 230         vdp_set_nametab_addr(plane, vdp_nametab_addr(idx));
 231 }
 232
 233 static inline void vdp_disable_layer(int plane)
 234 {
 235         switch(plane) {
 236         case VDP_PLANE_A:
 237                 vdp_setreg(VDP_REG_NAMETAB_A, 0x40);
 238                 break;
 239         case VDP_PLANE_B:
 240                 vdp_setreg(VDP_REG_NAMETAB_B, 0x08);
 241                 break;
 242         case VDP_PLANE_WIN:
 243                 vdp_setreg(VDP_REG_NAMETAB_WIN, 0x40);
 244         default:
 245                 break;
 246         }
 247 }
 248
 249 static inline uint16_t vdp_nametab_entry(int tileidx, int palidx, uint16_t flags)
 250 {
 251         return tileidx | (((uint16_t)palidx & 0x3) << 13) | flags;
 252 }
 253
 254 static inline void vdp_set_sprite_table(uint16_t addr)
 255 {
 256         vdp_setreg(VDP_REG_SPRITE_TAB, addr >> 9);
 257 }
 258
 259 static inline void vdp_set_scroll_table(uint16_t addr)
 260 {
 261         vdp_setreg(VDP_REG_SCROLL_TAB, addr >> 10);
 262 }
 263
 264 static inline void vdp_wait_vblank_start(void)
 265 {
 266         while(!(VDP_PORT_STATUS & VDP_STAT_VBLANK));
 267 }
 268
 269 static inline void vdp_wait_vblank_end(void)
 270 {
 271         while(VDP_PORT_STATUS & VDP_STAT_VBLANK);
 272 }
 273
 274 static inline void vdp_wait_vblank(void)
 275 {
 276         vdp_wait_vblank_start();
 277         vdp_wait_vblank_end();
 278 }
 279
 280 void vdp_init(void);
 281
 282 #endif  /* VDP_H_ */