gpsp/arm/arm_stub.S

883 lines
41 KiB
ArmAsm

#include "../gpsp_config.h"
#define defsymbl(symbol) \
.type symbol, %function ;\
.global symbol ; \
.global _##symbol ; \
symbol: \
_##symbol:
.text
.align 2
#define REG_R0 (0 * 4)
#define REG_R1 (1 * 4)
#define REG_R2 (2 * 4)
#define REG_R3 (3 * 4)
#define REG_R4 (4 * 4)
#define REG_R5 (5 * 4)
#define REG_R6 (6 * 4)
#define REG_R7 (7 * 4)
#define REG_R8 (8 * 4)
#define REG_R9 (9 * 4)
#define REG_R10 (10 * 4)
#define REG_R11 (11 * 4)
#define REG_R12 (12 * 4)
#define REG_R13 (13 * 4)
#define REG_R14 (14 * 4)
#define REG_SP (13 * 4)
#define REG_LR (14 * 4)
#define REG_PC (15 * 4)
#define REG_N_FLAG (16 * 4)
#define REG_Z_FLAG (17 * 4)
#define REG_C_FLAG (18 * 4)
#define REG_V_FLAG (19 * 4)
#define REG_CPSR (20 * 4)
#define REG_SAVE (21 * 4)
#define REG_SAVE2 (22 * 4)
#define REG_SAVE3 (23 * 4)
#define CPU_MODE (29 * 4)
#define CPU_HALT_STATE (30 * 4)
#define CHANGED_PC_STATUS (31 * 4)
#define COMPLETED_FRAME (32 * 4)
#define OAM_UPDATED (33 * 4)
#define reg_a0 r0
#define reg_a1 r1
#define reg_a2 r2
#define reg_s0 r9
#define reg_base r11
#define reg_flags r9
#define reg_cycles r12
#define reg_x0 r3
#define reg_x1 r4
#define reg_x2 r5
#define reg_x3 r6
#define reg_x4 r7
#define reg_x5 r8
#define MODE_SUPERVISOR 3
#define extract_u16(rd, rs) \
uxth rd, rs
@ Will load the register set from memory into the appropriate cached registers.
@ See arm_emit.h for listing explanation.
#define load_registers_arm() ;\
ldr reg_x0, [reg_base, #REG_R0] ;\
ldr reg_x1, [reg_base, #REG_R1] ;\
ldr reg_x2, [reg_base, #REG_R6] ;\
ldr reg_x3, [reg_base, #REG_R9] ;\
ldr reg_x4, [reg_base, #REG_R12] ;\
ldr reg_x5, [reg_base, #REG_R14] ;\
#define load_registers_thumb() ;\
ldr reg_x0, [reg_base, #REG_R0] ;\
ldr reg_x1, [reg_base, #REG_R1] ;\
ldr reg_x2, [reg_base, #REG_R2] ;\
ldr reg_x3, [reg_base, #REG_R3] ;\
ldr reg_x4, [reg_base, #REG_R4] ;\
ldr reg_x5, [reg_base, #REG_R5] ;\
@ Will store the register set from cached registers back to memory.
#define store_registers_arm() ;\
str reg_x0, [reg_base, #REG_R0] ;\
str reg_x1, [reg_base, #REG_R1] ;\
str reg_x2, [reg_base, #REG_R6] ;\
str reg_x3, [reg_base, #REG_R9] ;\
str reg_x4, [reg_base, #REG_R12] ;\
str reg_x5, [reg_base, #REG_R14] ;\
#define store_registers_thumb() ;\
str reg_x0, [reg_base, #REG_R0] ;\
str reg_x1, [reg_base, #REG_R1] ;\
str reg_x2, [reg_base, #REG_R2] ;\
str reg_x3, [reg_base, #REG_R3] ;\
str reg_x4, [reg_base, #REG_R4] ;\
str reg_x5, [reg_base, #REG_R5] ;\
@ Returns an updated persistent cpsr with the cached flags register.
@ Uses reg as a temporary register and returns the CPSR here.
#define collapse_flags_no_update(reg) ;\
ldr reg, [reg_base, #REG_CPSR] /* reg = cpsr */;\
bic reg, reg, #0xF0000000 /* clear ALU flags in cpsr */;\
and reg_flags, reg_flags, #0xF0000000 /* clear non-ALU flags */;\
orr reg, reg, reg_flags /* update cpsr with ALU flags */;\
@ Updates cpsr using the above macro.
#define collapse_flags(reg) ;\
collapse_flags_no_update(reg) ;\
str reg, [reg_base, #REG_CPSR] ;\
@ Loads the saved flags register from the persistent cpsr.
#define extract_flags() ;\
ldr reg_flags, [reg_base, #REG_CPSR] ;\
msr cpsr_f, reg_flags ;\
#define save_flags() ;\
mrs reg_flags, cpsr ;\
#define restore_flags() ;\
msr cpsr_f, reg_flags ;\
@ Align the stack to 64 bits (ABIs that don't require it, still recommend so)
#define call_c_saved_regs r2, r3, r12, lr
@ Calls a C function - reloads the stack pointer and saves all caller save
@ registers which are important to the dynarec.
#define call_c_function(function) ;\
stmdb sp!, { call_c_saved_regs } ;\
bl function ;\
ldmia sp!, { call_c_saved_regs } ;\
@ Jumps to PC (ARM or Thumb modes)
@ This is really two functions/routines in one
@ r0 contains the PC
.align 2
#define execute_pc_builder(mode, align) ;\
defsymbl(arm_indirect_branch_##mode) ;\
save_flags() ;\
execute_pc_##mode: ;\
bic r0, r0, #(align) /* Align PC */;\
mov r1, r0, lsr #24 /* Get region */;\
ldr pc, [pc, r1, lsl #2] ;\
nop ;\
.long 3f /* 0 BIOS (like ROM) */;\
.long 3f /* 1 Bad region */;\
.long 1f /* 2 EWRAM */;\
.long 2f /* 3 IWRAM */;\
.long 3f /* 4 Not supported */;\
.long 3f /* 5 Not supported */;\
.long 3f /* 6 Not supported */;\
.long 3f /* 7 Not supported */;\
.long 3f /* 8 ROM */;\
.long 3f /* 9 ROM */;\
.long 3f /* A ROM */;\
.long 3f /* B ROM */;\
.long 3f /* C ROM */;\
.long 3f /* D ROM */;\
.long 3f /* E ROM */;\
.long 3f /* F Bad region */;\
;\
3: ;\
call_c_function(block_lookup_address_##mode) ;\
restore_flags() ;\
bx r0 ;\
1: ;\
ldr r1, =(ewram+0x40000) /* Load base addr */;\
mov r2, r0, lsl #14 /* addr &= 0x3ffff */;\
mov r2, r2, lsr #14 ;\
ldrh r2, [r1, r2] /* Load half word there */;\
ldr r1, =(ram_block_ptrs) ;\
ldr r1, [r1, r2, lsl #2] /* Pointer to the cache */;\
cmp r1, #0 /* NULL means not translated */;\
beq 3b /* Need to translate */;\
restore_flags() ;\
bx r1 ;\
2: ;\
ldr r1, =(iwram) /* Load base addr */;\
mov r2, r0, lsl #17 /* addr &= 0x7fff */;\
mov r2, r2, lsr #17 ;\
ldrh r2, [r1, r2] /* Load half word there */;\
ldr r1, =(ram_block_ptrs) ;\
ldr r1, [r1, r2, lsl #2] /* Pointer to the cache */;\
cmp r1, #0 /* NULL means not translated */;\
beq 3b /* Need to translate */;\
restore_flags() ;\
bx r1 ;\
.size arm_indirect_branch_##mode, .-arm_indirect_branch_##mode
execute_pc_builder(arm, 0x3)
execute_pc_builder(thumb, 0x1)
@ Resumes execution from saved PC, in any mode
execute_pc:
ldr r0, [reg_base, #REG_PC] @ load new PC
ldr r1, [reg_base, #REG_CPSR] @ r1 = flags
tst r1, #0x20 @ see if Thumb bit is set
bne 2f
load_registers_arm()
b execute_pc_arm
2:
load_registers_thumb()
b execute_pc_thumb
@ Update the GBA hardware (video, sound, input, etc)
@ Input:
@ r0: current PC
#define return_straight() ;\
bx lr ;\
#define return_add() ;\
add pc, lr, #4 ;\
#define load_pc_straight() ;\
ldr r0, [lr, #-8] ;\
#define load_pc_add() ;\
ldr r0, [lr] ;\
#define arm_update_gba_builder(name, mode, return_op) ;\
;\
.align 2 ;\
defsymbl(arm_update_gba_##name) ;\
load_pc_##return_op() ;\
str r0, [reg_base, #REG_PC] /* write out the PC */;\
;\
save_flags() ;\
collapse_flags(r0) /* update the flags */;\
;\
store_registers_##mode() /* save out registers */;\
wait_halt_##name: ;\
call_c_function(update_gba) /* update GBA state */;\
;\
ldr r1, [reg_base, #COMPLETED_FRAME] /* return if new frame */;\
cmp r1, #0 ;\
bne return_to_main ;\
;\
ldr r1, [reg_base, #CPU_HALT_STATE] /* keep iterating if halted */;\
cmp r1, #0 ;\
bne wait_halt_##name ;\
;\
mvn reg_cycles, r0 /* load new cycle count */;\
;\
ldr r0, [reg_base, #CHANGED_PC_STATUS] /* load PC changed status */;\
cmp r0, #0 /* see if PC has changed */;\
bne execute_pc /* go jump/translate */;\
;\
load_registers_##mode() /* reload registers */;\
restore_flags() ;\
return_##return_op() /* continue, no PC change */;\
.size arm_update_gba_##mode, .-arm_update_gba_##mode
arm_update_gba_builder(arm, arm, straight)
arm_update_gba_builder(thumb, thumb, straight)
arm_update_gba_builder(idle_arm, arm, add)
arm_update_gba_builder(idle_thumb, thumb, add)
@ Cheat hooks for master function
@ This is called whenever PC == cheats-master-function
@ Just calls the C function to process cheats
#define cheat_hook_builder(mode) ;\
defsymbl(mode##_cheat_hook) ;\
save_flags() ;\
store_registers_##mode() ;\
call_c_function(process_cheats) ;\
load_registers_##mode() ;\
restore_flags() ;\
bx lr ;\
cheat_hook_builder(arm)
cheat_hook_builder(thumb)
@ These are b stubs for performing indirect branches. They are not
@ linked to and don't return, instead they link elsewhere.
@ Input:
@ r0: PC to branch to
.align 2
defsymbl(arm_indirect_branch_dual_arm)
save_flags()
tst r0, #0x01 @ check lower bit
beq execute_pc_arm @ Keep executing ARM code
bic r0, r0, #0x01 @ Switch to Thumb mode
store_registers_arm() @ save out ARM registers
load_registers_thumb() @ load in Thumb registers
ldr r1, [reg_base, #REG_CPSR] @ load cpsr
orr r1, r1, #0x20 @ set Thumb mode
str r1, [reg_base, #REG_CPSR] @ store flags
b execute_pc_thumb @ Now execute Thumb
.size arm_indirect_branch_dual_arm, .-arm_indirect_branch_dual_arm
.align 2
defsymbl(arm_indirect_branch_dual_thumb)
save_flags()
tst r0, #0x01 @ check lower bit
bne execute_pc_thumb @ Keep executing Thumb mode
store_registers_thumb() @ save out Thumb registers
load_registers_arm() @ load in ARM registers
ldr r1, [reg_base, #REG_CPSR] @ load cpsr
bic r1, r1, #0x20 @ clear Thumb mode
str r1, [reg_base, #REG_CPSR] @ store flags
b execute_pc_arm @ Now execute ARM
.size arm_indirect_branch_dual_thumb, .-arm_indirect_branch_dual_thumb
@ Update the cpsr.
@ Input:
@ r0: new cpsr value
@ r1: bitmask of which bits in cpsr to update
@ r2: current PC
.align 2
defsymbl(execute_store_cpsr)
save_flags()
and reg_flags, r0, r1 @ reg_flags = new_cpsr & store_mask
ldr r0, [reg_base, #REG_CPSR] @ r0 = cpsr
bic r0, r0, r1 @ r0 = cpsr & ~store_mask
orr reg_flags, reg_flags, r0 @ reg_flags = new_cpsr | cpsr
mov r0, reg_flags @ also put new cpsr in r0
store_registers_arm() @ save ARM registers
ldr r2, [lr] @ r2 = pc
call_c_function(execute_store_cpsr_body)
load_registers_arm() @ restore ARM registers
cmp r0, #0 @ check new PC
beq 1f @ if it's zero, return
b execute_pc_arm
1:
restore_flags()
add pc, lr, #4 @ return
.size execute_store_cpsr, .-execute_store_cpsr
@ Update the current spsr.
@ Input:
@ r0: new cpsr value
@ r1: bitmask of which bits in spsr to update
.align 2
defsymbl(execute_store_spsr)
ldr r1, =spsr @ r1 = spsr
ldr r2, [reg_base, #CPU_MODE] @ r2 = CPU_MODE
str r0, [r1, r2, lsl #2] @ spsr[CPU_MODE] = new_spsr
bx lr
.size execute_store_spsr, .-execute_store_spsr
@ Read the current spsr.
@ Output:
@ r0: spsr
.align 2
defsymbl(execute_read_spsr)
ldr r0, =spsr @ r0 = spsr
ldr r1, [reg_base, #CPU_MODE] @ r1 = CPU_MODE
ldr r0, [r0, r1, lsl #2] @ r0 = spsr[CPU_MODE]
bx lr @ return
.size execute_read_spsr, .-execute_read_spsr
@ Restore the cpsr from the mode spsr and mode shift.
@ Input:
@ r0: current pc
.align 2
defsymbl(execute_spsr_restore)
save_flags()
ldr r1, =spsr @ r1 = spsr
ldr r2, [reg_base, #CPU_MODE] @ r2 = cpu_mode
ldr r1, [r1, r2, lsl #2] @ r1 = spsr[cpu_mode] (new cpsr)
str r1, [reg_base, #REG_CPSR] @ update cpsr
mov reg_flags, r1 @ also, update shadow flags
@ This function call will pass r0 (address) and return it.
store_registers_arm() @ save ARM registers
call_c_function(execute_spsr_restore_body)
ldr r1, [reg_base, #REG_CPSR] @ r1 = cpsr
tst r1, #0x20 @ see if Thumb mode is set
bne 2f @ if so handle it
load_registers_arm() @ restore ARM registers
b execute_pc_arm
2:
load_registers_thumb() @ load Thumb registers
b execute_pc_thumb
@ Setup the mode transition work for calling an SWI.
@ Input:
@ r0: current pc
#define execute_swi_builder(mode) ;\
;\
.align 2 ;\
defsymbl(execute_swi_##mode) ;\
save_flags() ;\
ldr r1, =reg_mode /* r1 = reg_mode */;\
/* reg_mode[MODE_SUPERVISOR][6] = pc */;\
ldr r0, [lr] /* load PC */;\
str r0, [r1, #((MODE_SUPERVISOR * (7 * 4)) + (6 * 4))] ;\
collapse_flags_no_update(r0) /* r0 = cpsr */;\
ldr r1, =spsr /* r1 = spsr */;\
str r0, [r1, #(MODE_SUPERVISOR * 4)] /* spsr[MODE_SUPERVISOR] = cpsr */;\
bic r0, r0, #0x3F /* clear mode flag in r0 */;\
orr r0, r0, #0x13 /* set to supervisor mode */;\
str r0, [reg_base, #REG_CPSR] /* update cpsr */;\
;\
mov r0, #MODE_SUPERVISOR ;\
;\
store_registers_##mode() /* store regs for mode */;\
call_c_function(set_cpu_mode) /* set the CPU mode to svsr */;\
load_registers_arm() /* load ARM regs */;\
;\
restore_flags() ;\
add pc, lr, #4 /* return */;\
execute_swi_builder(arm)
execute_swi_builder(thumb)
@ Wrapper for calling SWI functions in C (or can implement some in ASM if
@ desired)
#define execute_swi_function_builder(swi_function, mode) ;\
;\
.align 2 ;\
defsymbl(execute_swi_hle_##swi_function##_##mode) ;\
save_flags() ;\
store_registers_##mode() ;\
call_c_function(execute_swi_hle_##swi_function##_c) ;\
load_registers_##mode() ;\
restore_flags() ;\
bx lr ;\
execute_swi_function_builder(div, arm)
execute_swi_function_builder(div, thumb)
@ Start program execution. Normally the mode should be Thumb and the
@ PC should be 0x8000000, however if a save state is preloaded this
@ will be different.
@ Input:
@ r0: initial value for cycle counter
@ Uses sp as reg_base; must hold consistently true.
.align 2
defsymbl(execute_arm_translate)
@ save the registers to be able to return later
stmdb sp!, { r4, r5, r6, r7, r8, r9, r10, r11, r12, lr }
ldr reg_base, =reg @ init base_reg
mvn reg_cycles, r0 @ load cycle counter
@ Check whether the CPU is sleeping already, we should just wait for IRQs
ldr r1, [reg_base, #CPU_HALT_STATE]
cmp r1, #0
bne alert_loop
ldr r0, [reg_base, #REG_PC] @ r0 = current pc
ldr r1, [reg_base, #REG_CPSR] @ r1 = flags
tst r1, #0x20 @ see if Thumb bit is set
bne 1f @ if so lookup thumb
load_registers_arm() @ load ARM registers
call_c_function(block_lookup_address_arm)
extract_flags() @ load flags
bx r0 @ jump to first ARM block
1:
load_registers_thumb() @ load Thumb registers
call_c_function(block_lookup_address_thumb)
extract_flags() @ load flags
bx r0 @ jump to first Thumb block
@ Epilogue to return to the main thread (whatever called execute_arm_translate)
return_to_main:
@ restore the saved regs and return
ldmia sp!, { r4, r5, r6, r7, r8, r9, r10, r11, r12, lr }
bx lr
#define store_align_8() ;\
and r1, r1, #0xff ;\
#define store_align_16() ;\
bic r0, r0, #0x01 ;\
extract_u16(r1, r1) ;\
#define store_align_32() ;\
bic r0, r0, #0x03 ;\
#define mask_addr_8(nbits) ;\
mov r0, r0, lsl #(32 - nbits) /* isolate bottom n bits in top */;\
mov r0, r0, lsr #(32 - nbits) /* high bits are now clear */;\
#define mask_addr_16(nbits) ;\
mov r0, r0, lsl #(32 - nbits) /* isolate bottom n bits in top */;\
mov r0, r0, lsr #(32 - nbits + 1) /* high bits are now clear */;\
mov r0, r0, lsl #1 /* LSB is also zero */;\
#define mask_addr_32(nbits) ;\
mov r0, r0, lsl #(32 - nbits) /* isolate bottom n bits in top */;\
mov r0, r0, lsr #(32 - nbits + 2) /* high bits are now clear */;\
mov r0, r0, lsl #2 /* 2 LSB are also zero */;\
@ Vram, OAM and palette memories can only be accessed at a 16 bit boundary
#define mask_addr_bus16_32(nbits) mask_addr_32(nbits)
#define mask_addr_bus16_16(nbits) mask_addr_16(nbits)
#define mask_addr_bus16_8(nbits) \
mask_addr_16(nbits) \
extract_u16(r1, r1)
@ Write out to memory.
@ Input:
@ r0: address
@ r1: value
@ r2: current pc
@
@ The instruction at LR is not an inst but a u32 data that contains the PC
@ Used for SMC. That's why return is essentially `pc = lr + 4`
#define execute_store_body(store_type, tblnum) ;\
save_flags() ;\
str lr, [reg_base, #REG_SAVE3] /* save lr */;\
;\
mov lr, r0, lsr #24 /* lr = region number */;\
cmp lr, #15 ;\
movcs lr, #15 /* lr = min(lr, 15) */;\
;\
add lr, lr, #(16*tblnum + 64) /* lr += table offset */;\
ldr pc, [reg_base, lr, lsl #2] /* jump to handler */;\
#define store_fnptr_table(store_type) ;\
ptr_tbl_##store_type: ;\
.word ext_store_ignore /* 0x00: BIOS, ignore */;\
.word ext_store_ignore /* 0x01: ignore */;\
.word ext_store_ewram_u##store_type /* 0x02: ewram */;\
.word ext_store_iwram_u##store_type /* 0x03: iwram */;\
.word ext_store_u##store_type /* 0x04: I/O regs */;\
.word ext_store_u##store_type /* 0x05: palette RAM */;\
.word ext_store_vram_u##store_type /* 0x06: vram */;\
.word ext_store_oam_ram_u##store_type /* 0x07: oam ram */;\
.word ext_store_u##store_type /* 0x08: gamepak: ignore */;\
.word ext_store_u##store_type /* 0x09: gamepak: ignore */;\
.word ext_store_u##store_type /* 0x0A: gamepak: ignore */;\
.word ext_store_u##store_type /* 0x0B: gamepak: ignore */;\
.word ext_store_u##store_type /* 0x0C: gamepak: ignore */;\
.word ext_store_u##store_type /* 0x0D: EEPROM */;\
.word ext_store_u##store_type /* 0x0E: backup */;\
.word ext_store_ignore /* 0x0F: ignore */;\
@ for ignored areas, just return
ext_store_ignore:
ldr lr, [reg_base, #REG_SAVE3] @ pop lr off of stack
restore_flags()
add pc, lr, #4 @ return
#define execute_store_builder(store_type, store_op, store_op16, load_op, tn) ;\
;\
.align 2 ;\
defsymbl(execute_store_u##store_type) ;\
execute_store_body(store_type, tn) ;\
;\
ext_store_u##store_type: ;\
ldr lr, [reg_base, #REG_SAVE3] /* pop lr off of stack */;\
ldr r2, [lr] /* load PC */;\
str r2, [reg_base, #REG_PC] /* write out PC */;\
store_align_##store_type() ;\
call_c_function(write_memory##store_type) ;\
b write_epilogue /* handle additional write stuff */;\
;\
ext_store_iwram_u##store_type: ;\
mask_addr_##store_type(15) /* Mask to mirror memory (+align)*/;\
ldr r2, =(iwram+0x8000) /* r2 = iwram base */;\
store_op r1, [r0, r2] /* store data */;\
sub r2, r2, #0x8000 /* r2 = iwram smc base */;\
load_op r1, [r0, r2] /* r1 = SMC sentinel */;\
cmp r1, #0 /* see if it's not 0 */;\
bne 3f /* if so perform smc write */;\
ldr lr, [reg_base, #REG_SAVE3] /* pop lr off of stack */;\
restore_flags() ;\
add pc, lr, #4 /* return */;\
;\
ext_store_ewram_u##store_type: ;\
mask_addr_##store_type(18) /* Mask to mirror memory (+align)*/;\
ldr r2, =(ewram) /* r2 = ewram base */;\
store_op r1, [r0, r2] /* store data */;\
add r2, r2, #0x40000 /* r2 = ewram smc base */;\
load_op r1, [r0, r2] /* r1 = SMC sentinel */;\
cmp r1, #0 /* see if it's not 0 */;\
bne 3f /* if so perform smc write */;\
ldr lr, [reg_base, #REG_SAVE3] /* pop lr off of stack */;\
restore_flags() ;\
add pc, lr, #4 /* return */;\
;\
ext_store_vram_u##store_type: ;\
mask_addr_bus16_##store_type(17) /* Mask to mirror memory (+align)*/;\
cmp r0, #0x18000 /* Check if exceeds 96KB */;\
subcs r0, r0, #0x8000 /* Mirror to the last bank */;\
ldr r2, =(vram) /* r2 = vram base */;\
store_op16 r1, [r0, r2] /* store data */;\
ldr lr, [reg_base, #REG_SAVE3] /* pop lr off of stack */;\
restore_flags() ;\
add pc, lr, #4 /* return */;\
;\
ext_store_oam_ram_u##store_type: ;\
mask_addr_bus16_##store_type(10) /* Mask to mirror memory (+align)*/;\
sub r2, reg_base, #0x400 /* r2 = oam ram base */;\
store_op16 r1, [r0, r2] /* store data */;\
str r2, [reg_base, #OAM_UPDATED] /* write non zero to signal */;\
ldr lr, [reg_base, #REG_SAVE3] /* pop lr off of stack */;\
restore_flags() ;\
add pc, lr, #4 /* return */;\
;\
3: ;\
ldr lr, [reg_base, #REG_SAVE3] /* restore lr */;\
ldr r0, [lr] /* load PC */;\
str r0, [reg_base, #REG_PC] /* write out PC */;\
b smc_write /* perform smc write */;\
.size execute_store_u##store_type, .-execute_store_u##store_type
execute_store_builder(8, strb, strh, ldrb, 0)
execute_store_builder(16, strh, strh, ldrh, 1)
execute_store_builder(32, str, str, ldr, 2)
@ This is a store that is executed in a strm case (so no SMC checks in-between)
defsymbl(execute_store_u32_safe)
execute_store_body(32_safe, 3)
restore_flags()
ldr pc, [reg_base, #REG_SAVE3] @ return
ext_store_u32_safe:
ldr lr, [reg_base, #REG_SAVE3] @ Restore lr
call_c_function(write_memory32) @ Perform 32bit store
restore_flags()
bx lr @ Return
ext_store_iwram_u32_safe:
mask_addr_8(15) @ Mask to mirror memory (no need to align!)
ldr r2, =(iwram+0x8000) @ r2 = iwram base
str r1, [r0, r2] @ store data
restore_flags()
ldr pc, [reg_base, #REG_SAVE3] @ return
ext_store_ewram_u32_safe:
mask_addr_8(18) @ Mask to mirror memory (no need to align!)
ldr r2, =(ewram) @ r2 = ewram base
str r1, [r0, r2] @ store data
restore_flags()
ldr pc, [reg_base, #REG_SAVE3] @ return
ext_store_vram_u32_safe:
mask_addr_8(17) @ Mask to mirror memory (no need to align!)
ldr r2, =(vram) @ r2 = vram base
cmp r0, #0x18000 @ Check if exceeds 96KB
subcs r0, r0, #0x8000 @ Mirror to the last bank
str r1, [r0, r2] @ store data
restore_flags()
ldr pc, [reg_base, #REG_SAVE3] @ return
ext_store_oam_ram_u32_safe:
mask_addr_8(10) @ Mask to mirror memory (no need to align!)
sub r2, reg_base, #0x400 @ r2 = oam ram base
str r1, [r0, r2] @ store data
str r2, [reg_base, #OAM_UPDATED] @ store anything non zero here
restore_flags()
ldr pc, [reg_base, #REG_SAVE3] @ return
.size execute_store_u32_safe, .-execute_store_u32_safe
write_epilogue:
cmp r0, #0 @ check if the write rose an alert
beq 4f @ if not we can exit
collapse_flags(r1) @ interrupt needs current flags
cmp r0, #2 @ see if the alert is due to SMC
beq smc_write @ if so, goto SMC handler
ldr r1, [reg_base, #REG_CPSR] @ r1 = cpsr
tst r1, #0x20 @ see if Thumb bit is set
bne 1f @ if so do Thumb update
store_registers_arm() @ save ARM registers
b alert_loop
1:
store_registers_thumb() @ save Thumb registers
alert_loop:
call_c_function(update_gba) @ update GBA until CPU isn't halted
ldr r1, [reg_base, #COMPLETED_FRAME] @ Check whether a frame was completed
cmp r1, #0
bne return_to_main
ldr r1, [reg_base, #CPU_HALT_STATE] @ Check whether the CPU is halted
cmp r1, #0
bne alert_loop @ Keep looping until it is
mvn reg_cycles, r0 @ load new cycle count
b execute_pc @ restart execution at PC
4:
restore_flags()
add pc, lr, #4 @ return
smc_write:
call_c_function(flush_translation_cache_ram)
lookup_pc:
ldr r0, [reg_base, #REG_PC] @ r0 = new pc
ldr r1, [reg_base, #REG_CPSR] @ r1 = flags
tst r1, #0x20 @ see if Thumb bit is set
beq execute_pc_arm @ if not lookup ARM
b execute_pc_thumb
#define sign_extend_u8(reg)
#define sign_extend_u16(reg)
#define sign_extend_u32(reg)
#define sign_extend_s8(reg) ;\
sxtb reg, reg
#define sign_extend_s16(reg) ;\
sxth reg, reg
#define execute_load_op_u8(load_op) ;\
mov r0, r0, lsl #17 ;\
load_op r0, [r2, r0, lsr #17] ;\
#define execute_load_op_s8(load_op) ;\
mov r0, r0, lsl #17 ;\
mov r0, r0, lsr #17 ;\
load_op r0, [r2, r0] ;\
#define execute_load_op_u16(load_op) ;\
execute_load_op_s8(load_op) ;\
#define execute_load_op_s16(load_op) ;\
execute_load_op_s8(load_op) ;\
#define execute_load_op_u16(load_op) ;\
execute_load_op_s8(load_op) ;\
#define execute_load_op_u32(load_op) ;\
execute_load_op_u8(load_op) ;\
#define execute_load_builder(load_type, load_function, load_op, mask) ;\
;\
.align 2 ;\
defsymbl(execute_load_##load_type) ;\
save_flags() ;\
tst r0, mask /* make sure address is in range */;\
bne ext_load_##load_type /* if not do ext load */;\
;\
ldr r2, =memory_map_read /* r2 = memory_map_read */;\
mov r1, r0, lsr #15 /* r1 = page index of address */;\
ldr r2, [r2, r1, lsl #2] /* r2 = memory page */;\
;\
cmp r2, #0 /* see if map is ext */;\
beq ext_load_##load_type /* if so do ext load */;\
;\
execute_load_op_##load_type(load_op) ;\
restore_flags() ;\
add pc, lr, #4 /* return */;\
;\
ext_load_##load_type: ;\
ldr r1, [lr] /* r1 = PC */;\
str r1, [reg_base, #REG_PC] /* update PC */;\
call_c_function(read_memory##load_function) ;\
sign_extend_##load_type(r0) /* sign extend result */;\
restore_flags() ;\
add pc, lr, #4 /* return */;\
.size execute_load_##load_type, .-execute_load_##load_type
.pool
execute_load_builder(u8, 8, ldrb, #0xF0000000)
execute_load_builder(s8, 8, ldrsb, #0xF0000000)
execute_load_builder(u16, 16, ldrh, #0xF0000001)
execute_load_builder(s16, 16_signed, ldrsh, #0xF0000001)
execute_load_builder(u32, 32, ldr, #0xF0000003)
.data
defsymbl(memory_map_read)
.space 0x8000
defsymbl(palette_ram)
.space 0x400
defsymbl(palette_ram_converted)
.space 0x400
defsymbl(spsr)
.space 24
defsymbl(reg_mode)
.space 196
defsymbl(oam_ram)
.space 0x400
defsymbl(reg)
.space 0x100, 0
@ Store pointer tables down here
store_fnptr_table(8)
store_fnptr_table(16)
store_fnptr_table(32)
store_fnptr_table(32_safe)
@ Vita and 3DS (and of course mmap) map their own cache sections through some
@ platform-speficic mechanisms.
#if !defined(HAVE_MMAP) && !defined(VITA) && !defined(_3DS)
@ Make this section executable!
.text
#ifdef __ANDROID__
@ Unfortunately Android builds don't like nobits, so we ship a ton of zeros
@ TODO: Revisit this whenever we upgrade to the latest clang NDK
.section .jit,"awx",%progbits
#else
.section .jit,"awx",%nobits
#endif
.align 4
defsymbl(rom_translation_cache)
.space ROM_TRANSLATION_CACHE_SIZE
.size rom_translation_cache, .-rom_translation_cache
defsymbl(ram_translation_cache)
.space RAM_TRANSLATION_CACHE_SIZE
.size ram_translation_cache, .-ram_translation_cache
#endif