diff --git a/agb/interrupt_simple.s b/agb/interrupt_simple.s index 817fd0b1..c86495a5 100644 --- a/agb/interrupt_simple.s +++ b/agb/interrupt_simple.s @@ -3,33 +3,43 @@ .global InterruptHandlerSimple .align InterruptHandlerSimple: - ldr r2, =0x04000200 @ interrupt enable register location - ldrh r1, [r2] @ load 16 bit interrupt enable to r1 - ldrh r3, [r2, #2] @ load 16 bit interrupt request to r3 + ldr r4, =0x04000200 @ interrupt enable register location + + @ disable interrupts by setting bit 0 to 0 + strh r2, [r4, #8] + + ldrh r1, [r4] @ load 16 bit interrupt enable to r1 + ldrh r3, [r4, #2] @ load 16 bit interrupt request to r3 and r0, r1, r3 @ interrupts both enabled and requested - strh r0, [r2, #2] @ store to interrupt request + strh r0, [r4, #2] @ store to interrupt request ldr r2, =0x03007FF8 @ load bios interrupt request location ldrh r1, [r2] @ load bios interrupt requests orr r1, r1, r0 @ or with enabled and requested interrupts strh r1, [r2] @ acknowlege bios requests + @ change to user mode mrs r2, cpsr orr r2, r2, #0xD msr cpsr_c, r2 - + @ call the rust interrupt handler with r0 set to the triggered interrupts ldr r1, =__RUST_INTERRUPT_HANDLER - push {lr} + push {lr, r4} adr lr, .IReturn bx r1 .IReturn: - pop {lr} + pop {lr, r4} + @ change back to interuupt mode mrs r2, cpsr bic r2, r2, #0xD orr r2, r2, #0x92 msr cpsr_c, r2 + @ reenable interrupts by setting bit 0 to 1 + mov r0, #1 + strh r0, [r4, #8] + bx lr @ return to bios .pool