mips_stub.s

psp上的GBA模拟器

execute_load_open_u32u1:
  open_load32_align32 2, 1, patch_load_u32
  ror $2, $2, 8                   # rotate value by 8bits


# Unsigned unaligned (by 2) 32bit load handlers

execute_load_bios_u32u2:
  region_check_align 0, 2, 2, patch_load_u32

  srl $2, $5, 14                  # check if PC is in BIOS region
  bne $2, $0, 1f                  # if not, perform BIOS protected read
  lui $1, %hi(bios_rom)           # generate upper address (delay)

  andi $4, $4, 0x3FFC             # generate offset
  addu $2, $1, $4
  load_u32_unaligned bios_rom, 2

1:
  lui $2, %hi(bios_read_protect)  # generate upper address
  load_u32_unaligned bios_read_protect, 2

execute_load_ewram_u32u2:
  translate_region_ewram_load_align32 2, 2, patch_load_u32
  load_u32_unaligned (ewram + 0x8000), 2

execute_load_iwram_u32u2:
  translate_region_align 3, 2, 2, patch_load_u32, (iwram + 0x8000), 0x7FFC
  load_u32_unaligned (iwram + 0x8000), 2

execute_load_io_u32u2:
  translate_region_align 4, 2, 2, patch_load_u32, io_registers, 0x3FC
  load_u32_unaligned io_registers, 2

execute_load_palette_u32u2:
  translate_region_align 5, 2, 2, patch_load_u32, palette_ram, 0x3FC
  load_u32_unaligned palette_ram, 2

execute_load_vram_u32u2:
  translate_region_vram_load_align32 2, 2, patch_load_u32
  load_u32_unaligned vram, 2

execute_load_oam_u32u2:
  translate_region_align 7, 2, 2, patch_load_u32, oam_ram, 0x3FC
  load_u32_unaligned oam_ram, 2

execute_load_gamepak8_u32u2:
  translate_region_gamepak_align32 8, 2, 2, patch_load_u32
  load_u32_unaligned 0, 2

execute_load_gamepak9_u32u2:
  translate_region_gamepak_align32 9, 2, 2, patch_load_u32
  load_u32_unaligned 0, 2

execute_load_gamepakA_u32u2:
  translate_region_gamepak_align32 10, 2, 2, patch_load_u32
  load_u32_unaligned 0, 2

execute_load_gamepakB_u32u2:
  translate_region_gamepak_align32 11, 2, 2, patch_load_u32
  load_u32_unaligned 0, 2

execute_load_gamepakC_u32u2:
  translate_region_gamepak_align32 12, 2, 2, patch_load_u32
  load_u32_unaligned 0, 2

execute_load_eeprom_u32u2:
  eeprom_load_align32 2, 2, patch_load_u32

execute_load_backup_u32u2:
  backup_load_align32 2, 2, patch_load_u32
  ror $2, $2, 16                   # rotate value by 16bits

execute_load_open_u32u2:
  open_load32_align32 2, 2, patch_load_u32
  ror $2, $2, 16                   # rotate value by 16bits

# Unsigned unaligned (by 1) 32bit load handlers

execute_load_bios_u32u3:
  region_check_align 0, 2, 3, patch_load_u32
  srl $2, $5, 14                  # check if PC is in BIOS region
  bne $2, $0, 1f                  # if not, perform BIOS protected read
  lui $1, %hi(bios_rom)           # generate upper address (delay)

  andi $4, $4, 0x3FFC             # generate offset
  addu $2, $1, $4
  load_u32_unaligned bios_rom, 3

1:
  lui $2, %hi(bios_read_protect)  # generate upper address
  load_u32_unaligned bios_read_protect, 3

execute_load_ewram_u32u3:
  translate_region_ewram_load_align32 2, 3, patch_load_u32
  load_u32_unaligned (ewram + 0x8000), 3

execute_load_iwram_u32u3:
  translate_region_align 3, 2, 3, patch_load_u32, (iwram + 0x8000), 0x7FFC
  load_u32_unaligned (iwram + 0x8000), 3

execute_load_io_u32u3:
  translate_region_align 4, 2, 3, patch_load_u32, io_registers, 0x3FC
  load_u32_unaligned io_registers, 3

execute_load_palette_u32u3:
  translate_region_align 5, 2, 3, patch_load_u32, palette_ram, 0x3FC
  load_u32_unaligned palette_ram, 3

execute_load_vram_u32u3:
  translate_region_vram_load_align32 2, 3, patch_load_u32
  load_u32_unaligned vram, 3

execute_load_oam_u32u3:
  translate_region_align 7, 2, 3, patch_load_u32, oam_ram, 0x3FC
  load_u32_unaligned oam_ram, 3

execute_load_gamepak8_u32u3:
  translate_region_gamepak_align32 8, 2, 3, patch_load_u32
  load_u32_unaligned 0, 3

execute_load_gamepak9_u32u3:
  translate_region_gamepak_align32 9, 2, 3, patch_load_u32
  load_u32_unaligned 0, 3

execute_load_gamepakA_u32u3:
  translate_region_gamepak_align32 10, 2, 3, patch_load_u32
  load_u32_unaligned 0, 3

execute_load_gamepakB_u32u3:
  translate_region_gamepak_align32 11, 2, 3, patch_load_u32
  load_u32_unaligned 0, 3

execute_load_gamepakC_u32u3:
  translate_region_gamepak_align32 12, 2, 3, patch_load_u32
  load_u32_unaligned 0, 3

execute_load_eeprom_u32u3:
  eeprom_load_align32 2, 3, patch_load_u32

execute_load_backup_u32u3:
  backup_load_align32 2, 3, patch_load_u32
  ror $2, $2, 24                  # rotate value by 24bits

execute_load_open_u32u3:
  open_load32_align32 2, 3, patch_load_u32
  ror $2, $2, 24                  # rotate value by 24bits


load_u32_ftable:
  .long execute_load_bios_u32     # 0x00 BIOS
  .long execute_load_open_u32     # 0x01 open address
  .long execute_load_ewram_u32    # 0x02 EWRAM
  .long execute_load_iwram_u32    # 0x03 IWRAM
  .long execute_load_io_u32       # 0x04 I/O registers
  .long execute_load_palette_u32  # 0x05 Palette RAM
  .long execute_load_vram_u32     # 0x06 VRAM
  .long execute_load_oam_u32      # 0x07 OAM RAM
  .long execute_load_gamepak8_u32 # 0x08 gamepak
  .long execute_load_gamepak9_u32 # 0x09 gamepak
  .long execute_load_gamepakA_u32 # 0x0A gamepak
  .long execute_load_gamepakB_u32 # 0x0B gamepak
  .long execute_load_gamepakC_u32 # 0x0C gamepak
  .long execute_load_eeprom_u32   # 0x0D gamepak/eeprom
  .long execute_load_backup_u32   # 0x0E Flash ROM/SRAM
  .long execute_load_open_u32     # 0x0F open

  .long execute_load_bios_u32u1     # 0x00 BIOS unaligned (1b)
  .long execute_load_open_u32u1     # 0x01 open address unaligned (1b)
  .long execute_load_ewram_u32u1    # 0x02 EWRAM unaligned (1b)
  .long execute_load_iwram_u32u1    # 0x03 IWRAM unaligned (1b)
  .long execute_load_io_u32u1       # 0x04 I/O registers unaligned (1b)
  .long execute_load_palette_u32u1  # 0x05 Palette RAM unaligned (1b)
  .long execute_load_vram_u32u1     # 0x06 VRAM unaligned (1b)
  .long execute_load_oam_u32u1      # 0x07 OAM RAM unaligned (1b)
  .long execute_load_gamepak8_u32u1 # 0x08 gamepak unaligned (1b)
  .long execute_load_gamepak9_u32u1 # 0x09 gamepak unaligned (1b)
  .long execute_load_gamepakA_u32u1 # 0x0A gamepak unaligned (1b)
  .long execute_load_gamepakB_u32u1 # 0x0B gamepak unaligned (1b)
  .long execute_load_gamepakC_u32u1 # 0x0C gamepak unaligned (1b)
  .long execute_load_eeprom_u32u1   # 0x0D gamepak/eeprom unaligned (1b)
  .long execute_load_backup_u32u1   # 0x0E Flash ROM/SRAM unaligned (1b)
  .long execute_load_open_u32u1     # 0x0F open unaligned (1b)

  .long execute_load_bios_u32u2     # 0x00 BIOS unaligned (2b)
  .long execute_load_open_u32u2     # 0x01 open address unaligned (2b)
  .long execute_load_ewram_u32u2    # 0x02 EWRAM unaligned (2b)
  .long execute_load_iwram_u32u2    # 0x03 IWRAM unaligned (2b)
  .long execute_load_io_u32u2       # 0x04 I/O registers unaligned (2b)
  .long execute_load_palette_u32u2  # 0x05 Palette RAM unaligned (2b)
  .long execute_load_vram_u32u2     # 0x06 VRAM unaligned (2b)
  .long execute_load_oam_u32u2      # 0x07 OAM RAM unaligned (2b)
  .long execute_load_gamepak8_u32u2 # 0x08 gamepak unaligned (2b)
  .long execute_load_gamepak9_u32u2 # 0x09 gamepak unaligned (2b)
  .long execute_load_gamepakA_u32u2 # 0x0A gamepak unaligned (2b)
  .long execute_load_gamepakB_u32u2 # 0x0B gamepak unaligned (2b)
  .long execute_load_gamepakC_u32u2 # 0x0C gamepak unaligned (2b)
  .long execute_load_eeprom_u32u2   # 0x0D gamepak/eeprom unaligned (2b)
  .long execute_load_backup_u32u2   # 0x0E Flash ROM/SRAM unaligned (2b)
  .long execute_load_open_u32u2     # 0x0F open unaligned (2b)

  .long execute_load_bios_u32u3     # 0x00 BIOS unaligned (3b)
  .long execute_load_open_u32u3     # 0x01 open address unaligned (3b)
  .long execute_load_ewram_u32u3    # 0x02 EWRAM unaligned (3b)
  .long execute_load_iwram_u32u3    # 0x03 IWRAM unaligned (3b)
  .long execute_load_io_u32u3       # 0x04 I/O registers unaligned (3b)
  .long execute_load_palette_u32u3  # 0x05 Palette RAM unaligned (3b)
  .long execute_load_vram_u32u3     # 0x06 VRAM unaligned (3b)
  .long execute_load_oam_u32u3      # 0x07 OAM RAM unaligned (3b)
  .long execute_load_gamepak8_u32u3 # 0x08 gamepak unaligned (3b)
  .long execute_load_gamepak9_u32u3 # 0x09 gamepak unaligned (3b)
  .long execute_load_gamepakA_u32u3 # 0x0A gamepak unaligned (3b)
  .long execute_load_gamepakB_u32u3 # 0x0B gamepak unaligned (3b)
  .long execute_load_gamepakC_u32u3 # 0x0C gamepak unaligned (3b)
  .long execute_load_eeprom_u32u3   # 0x0D gamepak/eeprom unaligned (3b)
  .long execute_load_backup_u32u3   # 0x0E Flash ROM/SRAM unaligned (3b)
  .long execute_load_open_u32u3     # 0x0F open unaligned (3b)

patch_load_u32:
  patch_handler_align load_u32_ftable, 2



# Unsigned always aligned 32bit load handlers

execute_load_bios_u32a:
  region_check 0, patch_load_u32a
  srl $2, $5, 14                  # check if PC is in BIOS region
  bne $2, $0, 1f                  # if not, perform BIOS protected read
  lui $1, %hi(bios_rom)           # generate upper address (delay)

  andi $4, $4, 0x3FFF             # generate offset
  addu $2, $1, $4
  load_u32 bios_rom

1:
  lui $2, %hi(bios_read_protect)  # generate upper address
  load_u32 bios_read_protect

execute_load_ewram_u32a:
  translate_region_ewram patch_load_u32a
  load_u32 (ewram + 0x8000)

execute_aligned_load32:
execute_load_iwram_u32a:
  translate_region 3, patch_load_u32a, (iwram + 0x8000), 0x7FFF
  load_u32 (iwram + 0x8000)

execute_load_io_u32a:
  translate_region 4, patch_load_u32a, io_registers, 0x3FF
  load_u32 io_registers

execute_load_palette_u32a:
  translate_region 5, patch_load_u32a, palette_ram, 0x3FF
  load_u32 palette_ram

execute_load_vram_u32a:
  translate_region_vram patch_load_u32a
  load_u32 vram

execute_load_oam_u32a:
  translate_region 7, patch_load_u32a, oam_ram, 0x3FF
  load_u32 oam_ram

execute_load_gamepak8_u32a:
  translate_region_gamepak_a 8, patch_load_u32a
  load_u32 0

execute_load_gamepak9_u32a:
  translate_region_gamepak_a 9, patch_load_u32a
  load_u32 0

execute_load_gamepakA_u32a:
  translate_region_gamepak_a 10, patch_load_u32a
  load_u32 0

execute_load_gamepakB_u32a:
  translate_region_gamepak_a 11, patch_load_u32a
  load_u32 0

execute_load_gamepakC_u32a:
  translate_region_gamepak_a 12, patch_load_u32a
  load_u32 0

execute_load_eeprom_u32a:
  eeprom_load_a patch_load_u32a

execute_load_backup_u32a:
  backup_load_a patch_load_u32a
  nop

execute_load_open_u32a:
  open_load32_a patch_load_u32a

load_u32a_ftable:
  .long execute_load_bios_u32a      # 0x00 BIOS unaligned (3b)
  .long execute_load_open_u32a      # 0x01 open address unaligned (3b)
  .long execute_load_ewram_u32a     # 0x02 EWRAM unaligned (3b)
  .long execute_load_iwram_u32a     # 0x03 IWRAM unaligned (3b)
  .long execute_load_io_u32a        # 0x04 I/O registers unaligned (3b)
  .long execute_load_palette_u32a   # 0x05 Palette RAM unaligned (3b)
  .long execute_load_vram_u32a      # 0x06 VRAM unaligned (3b)
  .long execute_load_oam_u32a       # 0x07 OAM RAM unaligned (3b)
  .long execute_load_gamepak8_u32a  # 0x08 gamepak unaligned (3b)
  .long execute_load_gamepak9_u32a  # 0x09 gamepak unaligned (3b)
  .long execute_load_gamepakA_u32a  # 0x0A gamepak unaligned (3b)
  .long execute_load_gamepakB_u32a  # 0x0B gamepak unaligned (3b)
  .long execute_load_gamepakC_u32a  # 0x0C gamepak unaligned (3b)
  .long execute_load_eeprom_u32a    # 0x0D gamepak/eeprom unaligned (3b)
  .long execute_load_backup_u32a    # 0x0E Flash ROM/SRAM unaligned (3b)
  .long execute_load_open_u32a      # 0x0F open unaligned (3b)

patch_load_u32a:
  patch_handler load_u32a_ftable, 1


# Unsigned 8bit store handlers

execute_store_ignore0_u8:
  ignore_region 0, patch_store_u8

execute_store_ignore1_u8:
  ignore_region 1, patch_store_u8

execute_store_ewram_u8:
  translate_region_ewram patch_store_u8
  store_u8_smc (ewram + 0x8000)

execute_store_u8:
execute_store_iwram_u8:
  translate_region 3, patch_store_u8, (iwram + 0x8000), 0x7FFF
  store_u8_smc (iwram + 0x8000)

execute_store_io_u8:
  region_check 4, patch_store_u8
  andi $5, $5, 0xFF               # make value 8bit
  andi $4, $4, 0x3FF              # wrap around address
  addiu $sp, $sp, -4              # make room on the stack for $ra
  sw $ra, ($sp)

  save_registers
  jal write_io_register8          # write the value out
  sw $6, REG_PC($16)              # save the PC (delay slot)
  j write_io_epilogue             # handle any state changes
  nop

execute_store_palette_u8:
  region_check 5, patch_store_u8
  lui $2, %hi(palette_ram)        # start loading palette_ram address (delay)
  ins $5, $5, 8, 8                # double value
  andi $4, $4, 0x3FE              # align palette address
  addu $2, $2, $4
  sh $5, %lo(palette_ram)($2)     # palette_ram[address] = value
  sll $1, $5, 1                   # make green 6bits
  ins $1, $0, 0, 6                # make bottom bit 0
  ins $1, $5, 0, 5                # insert red channel into $1
  lui $2, %hi(palette_ram_converted)
  addu $2, $2, $4
  jr $ra                          # return
  sh $1, %lo(palette_ram_converted)($2)

execute_store_vram_u8:
  translate_region_vram_store_align16 patch_store_u8
  store_u8_double vram

execute_store_oam_u8:
  translate_region 7, patch_store_u8, oam_ram, 0x3FE
  lui $1, %hi(oam_update)         # write non-zero to oam_update
  sw $4, %lo(oam_update)($1)      # cheap, but the address is non-zero
  store_u8_double oam_ram

execute_store_ignore8_u8:
  ignore_region 8, patch_store_u8

execute_store_ignore9_u8:
  ignore_region 9, patch_store_u8

execute_store_ignoreA_u8:
  ignore_region 10, patch_store_u8

execute_store_ignoreB_u8:
  ignore_region 11, patch_store_u8

execute_store_ignoreC_u8:
  ignore_region 12, patch_store_u8

execute_store_eeprom_u8:
  store_function write_eeprom, 13, patch_store_u8, 0x3FF

execute_store_backup_u8:
  store_function write_backup, 14, patch_store_u8, 0xFFFF

execute_store_ignoreF_u8:
  ignore_high patch_store_u8

store_u8_ftable:
  .long execute_store_ignore0_u8  # 0x00 BIOS
  .long execute_store_ignore1_u8  # 0x01 open address
  .long execute_store_ewram_u8    # 0x02 EWRAM
  .long execute_store_iwram_u8    # 0x03 IWRAM
  .long execute_store_io_u8       # 0x04 I/O registers
  .long execute_store_palette_u8  # 0x05 Palette RAM
  .long execute_store_vram_u8     # 0x06 VRAM
  .long execute_store_oam_u8      # 0x07 OAM RAM
  .long execute_store_ignore8_u8  # 0x08 gamepak
  .long execute_store_ignore9_u8  # 0x09 gamepak
  .long execute_store_ignoreA_u8  # 0x0A gamepak
  .long execute_store_ignoreB_u8  # 0x0B gamepak
  .long execute_store_ignoreC_u8  # 0x0C gamepak
  .long execute_store_eeprom_u8   # 0x0D gamepak/eeprom
  .long execute_store_backup_u8   # 0x0E Flash ROM/SRAM
  .long execute_store_ignoreF_u8  # 0x0F open address

patch_store_u8:
  patch_handler store_u8_ftable,