I believe this to be necessary in order to get hardware interrupts working. thumb.gba test 108 fails but I'm committing anyways (despite the regression) because this is kind of rebase/merge hell and I have something that at least sort of works rn
24 lines
777 B
Zig
24 lines
777 B
Zig
const Bus = @import("../../Bus.zig");
|
|
const Arm7tdmi = @import("../../cpu.zig").Arm7tdmi;
|
|
const InstrFn = @import("../../cpu.zig").thumb.InstrFn;
|
|
|
|
pub fn fmt17() InstrFn {
|
|
return struct {
|
|
fn inner(cpu: *Arm7tdmi, _: *Bus, _: u16) void {
|
|
// Copy Values from Current Mode
|
|
const ret_addr = cpu.r[15] - 2;
|
|
const cpsr = cpu.cpsr.raw;
|
|
|
|
// Switch Mode
|
|
cpu.changeMode(.Supervisor);
|
|
cpu.cpsr.t.write(false); // Force ARM Mode
|
|
cpu.cpsr.i.write(true); // Disable normal interrupts
|
|
|
|
cpu.r[14] = ret_addr; // Resume Execution
|
|
cpu.spsr.raw = cpsr; // Previous mode CPSR
|
|
cpu.r[15] = 0x0000_0008;
|
|
cpu.pipe.reload(u32, cpu);
|
|
}
|
|
}.inner;
|
|
}
|