some dma improvements

[picodrive.git] / pico / memory.h

// memory map related stuff

typedef unsigned char  u8;
typedef unsigned short u16;
typedef unsigned int   u32;
typedef unsigned long  uptr; // unsigned pointer-sized int

#define M68K_MEM_SHIFT 16
// minimum size we can map
#define M68K_BANK_SIZE (1 << M68K_MEM_SHIFT)
#define M68K_BANK_MASK (M68K_BANK_SIZE - 1)

extern uptr m68k_read8_map  [0x1000000 >> M68K_MEM_SHIFT];
extern uptr m68k_read16_map [0x1000000 >> M68K_MEM_SHIFT];
extern uptr m68k_write8_map [0x1000000 >> M68K_MEM_SHIFT];
extern uptr m68k_write16_map[0x1000000 >> M68K_MEM_SHIFT];

extern uptr s68k_read8_map  [0x1000000 >> M68K_MEM_SHIFT];
extern uptr s68k_read16_map [0x1000000 >> M68K_MEM_SHIFT];
extern uptr s68k_write8_map [0x1000000 >> M68K_MEM_SHIFT];
extern uptr s68k_write16_map[0x1000000 >> M68K_MEM_SHIFT];

// top-level handlers that cores can use
// (or alternatively build them into themselves)
// XXX: unhandled: *16 and *32 might cross the bank boundaries
typedef u32  (cpu68k_read_f)(u32 a);
typedef void (cpu68k_write_f)(u32 a, u32 d);

extern u32 m68k_read8(u32 a);
extern u32 m68k_read16(u32 a);
extern void m68k_write8(u32 a, u8 d);
extern void m68k_write16(u32 a, u16 d);

// z80
#define Z80_MEM_SHIFT 13
extern uptr z80_read_map [0x10000 >> Z80_MEM_SHIFT];
extern uptr z80_write_map[0x10000 >> Z80_MEM_SHIFT];
typedef unsigned char (z80_read_f)(unsigned short a);
typedef void (z80_write_f)(unsigned int a, unsigned char data);

void z80_map_set(uptr *map, int start_addr, int end_addr,
    const void *func_or_mh, int is_func);
void cpu68k_map_set(uptr *map, int start_addr, int end_addr,
    const void *func_or_mh, int is_func);
void cpu68k_map_all_ram(int start_addr, int end_addr, void *ptr, int is_sub);
void m68k_map_unmap(int start_addr, int end_addr);

#define MAP_FLAG ((uptr)1 << (sizeof(uptr) * 8 - 1))
#define map_flag_set(x) ((x) & MAP_FLAG)

#define MAKE_68K_READ8(name, map)               \
u32 name(u32 a)                                 \
{                                               \
  uptr v;                                       \
  a &= 0x00ffffff;                              \
  v = map[a >> M68K_MEM_SHIFT];                 \
  if (map_flag_set(v))                          \
    return ((cpu68k_read_f *)(v << 1))(a);      \
  else                                          \
    return *(u8 *)((v << 1) + (a ^ 1));         \
}

#define MAKE_68K_READ16(name, map)              \
u32 name(u32 a)                                 \
{                                               \
  uptr v;                                       \
  a &= 0x00fffffe;                              \
  v = map[a >> M68K_MEM_SHIFT];                 \
  if (map_flag_set(v))                          \
    return ((cpu68k_read_f *)(v << 1))(a);      \
  else                                          \
    return *(u16 *)((v << 1) + a);              \
}

#define MAKE_68K_READ32(name, map)              \
u32 name(u32 a)                                 \
{                                               \
  uptr v, vs;                                   \
  u32 d;                                        \
  a &= 0x00fffffe;                              \
  v = map[a >> M68K_MEM_SHIFT];                 \
  vs = v << 1;                                  \
  if (map_flag_set(v)) {                        \
    d  = ((cpu68k_read_f *)vs)(a) << 16;        \
    d |= ((cpu68k_read_f *)vs)(a + 2);          \
  }                                             \
  else {                                        \
    u16 *m = (u16 *)(vs + a);                   \
    d = (m[0] << 16) | m[1];                    \
  }                                             \
  return d;                                     \
}

#define MAKE_68K_WRITE8(name, map)              \
void name(u32 a, u8 d)                          \
{                                               \
  uptr v;                                       \
  a &= 0x00ffffff;                              \
  v = map[a >> M68K_MEM_SHIFT];                 \
  if (map_flag_set(v))                          \
    ((cpu68k_write_f *)(v << 1))(a, d);         \
  else                                          \
    *(u8 *)((v << 1) + (a ^ 1)) = d;            \
}

#define MAKE_68K_WRITE16(name, map)             \
void name(u32 a, u16 d)                         \
{                                               \
  uptr v;                                       \
  a &= 0x00fffffe;                              \
  v = map[a >> M68K_MEM_SHIFT];                 \
  if (map_flag_set(v))                          \
    ((cpu68k_write_f *)(v << 1))(a, d);         \
  else                                          \
    *(u16 *)((v << 1) + a) = d;                 \
}

#define MAKE_68K_WRITE32(name, map)             \
void name(u32 a, u32 d)                         \
{                                               \
  uptr v, vs;                                   \
  a &= 0x00fffffe;                              \
  v = map[a >> M68K_MEM_SHIFT];                 \
  vs = v << 1;                                  \
  if (map_flag_set(v)) {                        \
    ((cpu68k_write_f *)vs)(a, d >> 16);         \
    ((cpu68k_write_f *)vs)(a + 2, d);           \
  }                                             \
  else {                                        \
    u16 *m = (u16 *)(vs + a);                   \
    m[0] = d >> 16;                             \
    m[1] = d;                                   \
  }                                             \
}

#ifdef NEED_DMA_SOURCE // meh

static __inline void *m68k_dma_source(u32 a)
{
  u8 *base;
  uptr v;
  v = m68k_read16_map[a >> M68K_MEM_SHIFT];
  if (map_flag_set(v)) {
    if (a >= Pico.romsize) // Rom
      return NULL;
    base = Pico.rom;
  }
  else
    base = (void *)(v << 1);
  return base + (a & 0xfe0000);
}

#endif

// 32x
typedef struct {
  uptr addr; // stores (membase >> 1) or ((handler >> 1) | (1<<31))
  u32 mask;
} sh2_memmap;