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authorAutechre2021-03-09 20:31:50 +0100
committerGitHub2021-03-09 20:31:50 +0100
commit45c8ef0a0bdf0557ab9c1153b5a6e77298cca34a (patch)
tree45b66118646d122a395cfecf2d740bed854c4e45 /arm
parent6a8aa84200eb92a7f3f1b4befb0630d95ad59b8e (diff)
parent0522d9a4f535a61953da64518097fc7f64d7120c (diff)
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Merge pull request #101 from davidgfnet/master
Remove libco
Diffstat (limited to 'arm')
-rw-r--r--arm/arm_stub.S65
1 files changed, 50 insertions, 15 deletions
diff --git a/arm/arm_stub.S b/arm/arm_stub.S
index 0de4cb4..7deffc0 100644
--- a/arm/arm_stub.S
+++ b/arm/arm_stub.S
@@ -39,9 +39,9 @@
#define CPU_MODE (29 * 4)
#define CPU_HALT_STATE (30 * 4)
#define CHANGED_PC_STATUS (31 * 4)
+#define COMPLETED_FRAME (32 * 4)
-#define REG_HOST_SP (32 * 4)
-
+#define MAIN_THREAD_SP (33 * 4)
#define reg_a0 r0
#define reg_a1 r1
@@ -147,11 +147,11 @@
@ registers which are important to the dynarec.
#define call_c_function(function) ;\
- ldr sp, [reg_base, #REG_HOST_SP] ;\
+ ldr sp, [reg_base, #MAIN_THREAD_SP] ;\
stmdb sp!, { call_c_saved_regs } ;\
bl function ;\
ldmia sp!, { call_c_saved_regs } ;\
- ldr sp, =base_reg_area ;\
+ ldr sp, =reg ;\
@ Update the GBA hardware (video, sound, input, etc)
@@ -186,8 +186,17 @@ _arm_update_gba_##name: ;\
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 */;\
@@ -479,14 +488,20 @@ execute_swi_function_builder(div, thumb)
.globl _execute_arm_translate
execute_arm_translate:
_execute_arm_translate:
- ldr r1, =base_reg_area @ base_reg_area to r1
- str sp, [r1, #REG_HOST_SP] @ store the current sp
- ldr sp, =base_reg_area @ reg_base = sp (loading addr)
+
+ @ save the registers to be able to return later
+ stmdb sp!, { r4, r5, r6, r7, r8, r9, r10, r11, r12, lr }
+
+ ldr r1, =reg @ reg to r1
+ str sp, [r1, #MAIN_THREAD_SP] @ store the current sp
+ ldr sp, =reg @ reg_base = sp (loading addr)
mvn reg_cycles, r0 @ load cycle counter
- mov r0, reg_base @ load reg_base into first param
- call_c_function(move_reg) @ make reg_base the new reg ptr
+ @ 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
@@ -506,6 +521,16 @@ _execute_arm_translate:
bx r0 @ jump to first Thumb block
+@ Epilogue to return to the main thread (whatever called execute_arm_translate)
+
+return_to_main:
+ @ restore the stack pointer
+ ldr sp, [reg_base, #MAIN_THREAD_SP]
+ @ restore the saved regs and return
+ ldmia sp!, { r4, r5, r6, r7, r8, r9, r10, r11, r12, lr }
+ bx lr
+
+
@ Write out to memory.
@ Input:
@@ -607,10 +632,22 @@ write_epilogue:
bne 1f @ if so do Thumb update
store_registers_arm() @ save ARM registers
+ b alert_loop
-3:
+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
ldr r0, [reg_base, #REG_PC] @ load new PC
ldr r1, [reg_base, #REG_CPSR] @ r1 = flags
@@ -622,10 +659,6 @@ write_epilogue:
restore_flags()
bx r0 @ jump to new ARM block
-1:
- store_registers_thumb() @ save Thumb registers
- b 3b
-
2:
load_registers_thumb()
call_c_function(block_lookup_address_thumb)
@@ -735,6 +768,8 @@ execute_load_builder(u32, 32, ldrne, #0xF0000000)
.data
-base_reg_area:
+.globl reg
+.globl _reg
+reg:
.space 0x100, 0