1 files changed, 65 insertions, 0 deletions
diff --git a/arm7/asm/OS_context.s b/arm7/asm/OS_context.s
new file mode 100644
index 00000000..21479b1f
--- /dev/null
+++ b/arm7/asm/OS_context.s
@@ -0,0 +1,65 @@
+    .include "asm/macros.inc"
+    .include "global.inc"
+
+    .text
+
+	arm_func_start OS_InitContext
+OS_InitContext: ; 0x037F9740
+	add	r1, r1, #4
+	str	r1, [r0, #64]	; 0x40
+	str	r2, [r0, #68]	; 0x44
+	sub	r2, r2, #64	; 0x40
+	tst	r2, #4
+	subne	r2, r2, #4
+	str	r2, [r0, #56]	; 0x38
+	ands	r1, r1, #1
+	movne	r1, #63	; 0x3f
+	moveq	r1, #31
+	str	r1, [r0]
+	mov	r1, #0
+	str	r1, [r0, #4]
+	str	r1, [r0, #8]
+	str	r1, [r0, #12]
+	str	r1, [r0, #16]
+	str	r1, [r0, #20]
+	str	r1, [r0, #24]
+	str	r1, [r0, #28]
+	str	r1, [r0, #32]
+	str	r1, [r0, #36]	; 0x24
+	str	r1, [r0, #40]	; 0x28
+	str	r1, [r0, #44]	; 0x2c
+	str	r1, [r0, #48]	; 0x30
+	str	r1, [r0, #52]	; 0x34
+	str	r1, [r0, #60]	; 0x3c
+	bx	lr
+
+	arm_func_start OS_SaveContext
+OS_SaveContext: ; 0x037F97AC
+	add	r1, r0, #0
+	mrs	r2, CPSR
+	str	r2, [r1], #4
+	mov	r0, #211	; 0xd3
+	msr	CPSR_c, r0
+	str	sp, [r1, #64]	; 0x40
+	msr	CPSR_c, r2
+	mov	r0, #1
+	stmia	r1, {r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, sl, fp, ip, sp, lr}
+	adr	r0, _037F97E0
+	str	r0, [r1, #60]	; 0x3c
+	mov	r0, #0
+	bx	lr
+
+	arm_func_start OS_LoadContext
+OS_LoadContext: ; 0x037F97E0
+_037F97E0: ; needed because otherwise it breaks
+	mrs	r1, CPSR
+	bic	r1, r1, #31
+	orr	r1, r1, #211	; 0xd3
+	msr	CPSR_c, r1
+	ldr	r1, [r0], #4
+	msr	SPSR_fsxc, r1
+	ldr	sp, [r0, #64]	; 0x40
+	ldr	lr, [r0, #60]	; 0x3c
+	ldmia	r0, {r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, sl, fp, ip, sp, lr}^
+	nop			; (mov r0, r0)
+	subs	pc, lr, #4