gb-emu/lib/src/processor/memory.rs
2023-03-19 12:43:10 +11:00

370 lines
12 KiB
Rust

pub use self::rom::Rom;
use self::{
mmio::{
apu::ApuSaveState,
gpu::{Colour, GpuSaveState},
serial::SerialSaveState,
Apu, Gpu, Joypad, Serial, Timer,
},
rom::RomSaveState,
};
use crate::{
connect::{AudioOutput, CameraWrapperRef, JoypadState, PocketCamera, Renderer, SerialTarget},
processor::SplitRegister,
verbose_println, Cpu,
};
mod interrupts;
pub use interrupts::{Interrupt, Interrupts};
use serde::{Deserialize, Serialize};
pub mod mmio;
pub(crate) mod rom;
pub(crate) type Address = u16;
pub struct Memory<ColourFormat, R, C>
where
ColourFormat: From<Colour> + Clone,
R: Renderer<ColourFormat>,
C: PocketCamera + Send + 'static,
{
bootrom: Option<Vec<u8>>,
rom: Rom<C>,
ram: [u8; 8192],
cpu_ram: [u8; 128],
pub(super) interrupts: Interrupts,
pub(super) ime: bool,
pub(super) ime_scheduled: u8,
dma_addr: u8,
joypad: Joypad,
gpu: Gpu<ColourFormat, R>,
apu: Apu,
serial: Serial,
timers: Timer,
camera: CameraWrapperRef<C>,
}
#[serde_with::serde_as]
#[derive(Serialize, Deserialize)]
pub struct MemorySaveState<ColourFormat, R>
where
ColourFormat: From<Colour> + Clone,
R: Renderer<ColourFormat>,
{
rom: RomSaveState,
#[serde_as(as = "[_; 8192]")]
ram: [u8; 8192],
#[serde_as(as = "[_; 128]")]
cpu_ram: [u8; 128],
pub(super) interrupts: Interrupts,
pub(super) ime: bool,
pub(super) ime_scheduled: u8,
dma_addr: u8,
joypad: Joypad,
gpu: GpuSaveState<ColourFormat, R>,
apu: ApuSaveState,
serial: SerialSaveState,
timers: Timer,
}
impl<ColourFormat, R> MemorySaveState<ColourFormat, R>
where
ColourFormat: From<Colour> + Clone,
R: Renderer<ColourFormat>,
// C: PocketCamera + Send + 'static,
{
pub fn create<C: PocketCamera + Send + 'static>(memory: &Memory<ColourFormat, R, C>) -> Self {
Self {
rom: RomSaveState::create(&memory.rom),
ram: memory.ram,
cpu_ram: memory.cpu_ram,
interrupts: memory.interrupts,
ime: memory.ime,
ime_scheduled: memory.ime_scheduled,
dma_addr: memory.dma_addr,
joypad: memory.joypad,
gpu: GpuSaveState::create(&memory.gpu),
apu: ApuSaveState::create(&memory.apu),
serial: SerialSaveState::create(&memory.serial),
timers: memory.timers,
}
}
}
impl<ColourFormat, R, C> Memory<ColourFormat, R, C>
where
ColourFormat: From<Colour> + Clone,
R: Renderer<ColourFormat>,
C: PocketCamera + Send + 'static,
{
pub(crate) fn init(
bootrom: Option<Vec<u8>>,
rom: Rom<C>,
window: R,
output: AudioOutput,
serial_target: SerialTarget,
tile_window: Option<R>,
camera: CameraWrapperRef<C>,
) -> Self {
Self {
bootrom,
rom,
ram: [0x0; 8192],
cpu_ram: [0x0; 128],
interrupts: Interrupts::default(),
ime: false,
ime_scheduled: 0x0,
dma_addr: 0xFF,
joypad: Joypad::default(),
gpu: Gpu::new(window, tile_window),
apu: Apu::new(output),
serial: Serial::new(serial_target),
timers: Timer::init(),
camera,
}
}
pub fn get(&self, address: Address) -> u8 {
match address {
0x0..0x8000 => {
// rom access
// todo - switchable rom banks
if let Some(bootrom) = &self.bootrom && (address as usize) < bootrom.len() {
bootrom[address as usize]
} else {
self.rom.get(address)
}
}
0x8000..0xA000 => self.gpu.vram.get(address),
0xA000..0xC000 => {
// cart ram
self.rom.get_ram(address)
}
0xC000..0xE000 => self.ram[(address - 0xC000) as usize],
0xE000..0xFE00 => self.ram[(address - 0xE000) as usize],
0xFE00..0xFEA0 => self.gpu.oam.get(address),
0xFEA0..0xFF00 => 0xFF,
0xFF00..0xFF4C => self.get_io(address),
0xFF4C..0xFF80 => 0xFF,
0xFF80..0xFFFF => self.cpu_ram[(address - 0xFF80) as usize],
0xFFFF => self.interrupts.get_enable_register(),
}
}
pub fn set(&mut self, address: Address, data: u8) {
match address {
0x0..0x8000 => {
// change this with MBC code...
self.rom.set(address, data);
if self.rom.can_rumble() {
// rumble
self.gpu.window.set_rumble(self.rom.is_rumbling())
}
}
0x8000..0xA000 => self.gpu.vram.set(address, data),
0xA000..0xC000 => self.rom.set_ram(address, data),
0xC000..0xE000 => self.ram[(address - 0xC000) as usize] = data,
0xE000..0xFE00 => self.ram[(address - 0xE000) as usize] = data,
0xFE00..0xFEA0 => self.gpu.oam.set(address, data),
0xFEA0..0xFF00 => {}
0xFF00..0xFF4C => self.set_io(address, data),
0xFF50 => self.bootrom = None,
0xFF4C..0xFF50 | 0xFF51..0xFF80 => {}
0xFF80..0xFFFF => self.cpu_ram[(address - 0xFF80) as usize] = data,
0xFFFF => {
verbose_println!("interrupts set to {:#b}", data);
verbose_println!(" / {:#X}", data);
self.interrupts.set_enable_register(data);
}
}
}
fn get_io(&self, address: Address) -> u8 {
// range: 0xFF00 - 0xFF4B inclusive
match address {
0xFF00 => self.joypad.as_register(),
0xFF01 => self.serial.get_queued(),
0xFF02 => self.serial.get_control(),
0xFF04 => self.timers.get_div(),
0xFF05 => self.timers.get_tima(),
0xFF06 => self.timers.get_tma(),
0xFF07 => self.timers.get_timer_control(),
0xFF0F => self.interrupts.get_flag_register(),
0xFF10..0xFF40 => self.apu.get_register(address),
0xFF40 => self.gpu.get_lcdc(),
0xFF41 => self.gpu.get_lcd_status(),
0xFF42 => self.gpu.get_scy(),
0xFF43 => self.gpu.get_scx(),
0xFF44 => self.gpu.get_ly(),
0xFF45 => self.gpu.get_lyc(),
0xFF46 => self.dma_addr,
0xFF47 => self.gpu.get_bg_palette(),
0xFF48 => self.gpu.get_obj_palette_0(),
0xFF49 => self.gpu.get_obj_palette_1(),
0xFF4A => self.gpu.get_wy(),
0xFF4B => self.gpu.get_wx(),
0xFF03 | 0xFF08..0xFF0F => 0xFF,
0x0..0xFF00 | 0xFF4C..=0xFFFF => panic!("passed wrong address to get_io"),
}
}
fn set_io(&mut self, address: Address, data: u8) {
// range: 0xFF00 - 0xFF4B inclusive
match address {
0xFF00 => {
// joypad
self.joypad.mmio_write(data);
}
0xFF01 => self.serial.update_queued(data),
0xFF02 => self.serial.update_control(data),
0xFF04 => self.timers.update_div(),
0xFF05 => self.timers.update_tima(data),
0xFF06 => self.timers.update_tma(data),
0xFF07 => self.timers.update_timer_control(data),
0xFF0F => self.interrupts.set_flag_register(data),
0xFF10..0xFF40 => self.apu.mmio_write(address, data),
0xFF40 => self.gpu.update_lcdc(data),
0xFF41 => self.gpu.update_lcd_status(data),
0xFF42 => self.gpu.update_scy(data),
0xFF43 => self.gpu.update_scx(data),
0xFF45 => self.gpu.update_lyc(data),
0xFF46 => {
if data > 0xDF {
panic!("dma transfer out of bounds: {data:#X}");
}
self.dma_addr = data;
let mut addr: u16 = 0x0;
addr.set_high(data);
for l in 0x0..0xA0 {
addr.set_low(l);
self.gpu.oam.data[l as usize] = self.get(addr);
}
}
0xFF47 => self.gpu.update_bg_palette(data),
0xFF48 => self.gpu.update_obj_palette_0(data),
0xFF49 => self.gpu.update_obj_palette_1(data),
0xFF4A => self.gpu.update_wy(data),
0xFF4B => self.gpu.update_wx(data),
0xFF03 | 0xFF08..0xFF0F | 0xFF44 => {
// read-only addresses
verbose_println!("BANNED write: {data:#X} to {address:#X}");
}
0x0..0xFF00 | 0xFF4C..=u16::MAX => panic!("passed wrong address to set_io"),
}
}
pub fn update_pressed_keys(&mut self, latest_state: JoypadState) -> bool {
self.joypad.update_pressed_keys(latest_state)
}
pub(super) fn cpu_ram_init(&mut self) {
self.set(0xFF04, 0xAD);
// self.set(0xFF10, 0x80);
// self.set(0xFF11, 0xBF);
// self.set(0xFF12, 0xF3);
// self.set(0xFF14, 0xBF);
// self.set(0xFF16, 0x3F);
// self.set(0xFF19, 0xBF);
// self.set(0xFF1A, 0x7F);
// self.set(0xFF1B, 0xFF);
// self.set(0xFF1C, 0x9F);
// self.set(0xFF1E, 0xBF);
// self.set(0xFF20, 0xFF);
// self.set(0xFF23, 0xBF);
// self.set(0xFF24, 0x77);
// self.set(0xFF25, 0xF3);
// self.set(0xFF26, 0xF1);
self.set(0xFF40, 0x91);
self.set(0xFF47, 0xFC);
self.set(0xFF48, 0xFF);
self.set(0xFF49, 0xFF);
for i in 0xC000..0xE000 {
self.set(i, if rand::random() { 0xFF } else { 0x00 });
}
}
pub fn flush_rom(&mut self) {
self.rom.flush();
}
pub fn is_audio_buffer_full(&self) -> bool {
self.apu.is_buffer_full()
}
pub fn replace_output(&mut self, new: AudioOutput) {
self.apu.replace_output(new);
}
pub(crate) fn from_save_state(
state: MemorySaveState<ColourFormat, R>,
data: Vec<u8>,
window: R,
output: AudioOutput,
serial_target: SerialTarget,
camera: CameraWrapperRef<C>,
) -> Self {
Self {
bootrom: None,
rom: Rom::from_save_state(state.rom, data, camera.clone()),
ram: state.ram,
cpu_ram: state.cpu_ram,
interrupts: state.interrupts,
ime: state.ime,
ime_scheduled: state.ime_scheduled,
dma_addr: state.dma_addr,
joypad: state.joypad,
gpu: Gpu::from_save_state(state.gpu, window, None),
apu: Apu::from_save_state(state.apu, output),
serial: Serial::from_save_state(state.serial, serial_target),
timers: state.timers,
camera,
}
}
}
impl<ColourFormat, R, C> Cpu<ColourFormat, R, C>
where
ColourFormat: From<Colour> + Clone,
R: Renderer<ColourFormat>,
C: PocketCamera + Send + 'static,
{
pub fn increment_timers(&mut self, machine_cycles: u8) {
let steps = (machine_cycles as usize) * 4;
self.memory.camera.lock().unwrap().tick(steps);
let timer_return = self.memory.timers.tick(steps);
for _ in 0..timer_return.num_apu_ticks {
self.memory.apu.div_apu_tick();
}
if timer_return.timer_interrupt {
self.memory.interrupts.set_interrupt(Interrupt::Timer, true);
}
self.memory.apu.tick(steps);
let serial_interrupt = self.memory.serial.tick(steps, self.memory.ime);
self.memory
.interrupts
.set_interrupt(Interrupt::Serial, serial_interrupt);
let gpu_interrupts = self.memory.gpu.tick(steps);
self.memory
.interrupts
.set_interrupt(Interrupt::Vblank, gpu_interrupts.vblank);
self.memory
.interrupts
.set_interrupt(Interrupt::LcdStat, gpu_interrupts.lcd_stat);
if gpu_interrupts.vblank {
let latest_state = self.memory.gpu.window.latest_joypad_state();
let joypad_interrupt = self.memory.update_pressed_keys(latest_state);
self.memory
.interrupts
.set_interrupt(Interrupt::Joypad, joypad_interrupt);
}
}
}