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chore: misc style changes

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This commit is contained in:
Rekai Nyangadzayi Musuka
2022-12-28 06:51:02 -06:00
parent caaa60d1a8
commit 0cec779545
3 changed files with 84 additions and 91 deletions
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91
src/core/Bus.zig
View File

@@ -60,9 +60,8 @@ allocator: Allocator,
pub fn init(self: *Self, allocator: Allocator, sched: *Scheduler, cpu: *Arm7tdmi, paths: FilePaths) !void {
const tables = try allocator.alloc(?*anyopaque, 3 * table_len); // Allocate all tables
const read_table: *[table_len]?*const anyopaque = tables[0..table_len];
const left_write: *[table_len]?*anyopaque = tables[table_len .. 2 * table_len];
const right_write: *[table_len]?*anyopaque = tables[2 * table_len .. 3 * table_len];
const read_table = tables[0..table_len];
const write_tables = .{ tables[table_len .. 2 * table_len], tables[2 * table_len .. 3 * table_len] };
self.* = .{
.pak = try GamePak.init(allocator, cpu, paths.rom, paths.save),
@@ -78,18 +77,15 @@ pub fn init(self: *Self, allocator: Allocator, sched: *Scheduler, cpu: *Arm7tdmi
.sched = sched,
.read_table = read_table,
.write_tables = .{ left_write, right_write },
.write_tables = write_tables,
.allocator = allocator,
};
// read_table, write_tables, and *Self are not restricted to the lifetime
// of this init function so we can initialize our tables here
fillReadTable(self, read_table);
self.fillReadTable(read_table);
// Internal Display Memory behavious unusually on 8-bit reads
// so we have two different tables depending on whether there's an 8-bit read or not
fillWriteTable(u32, self, left_write);
fillWriteTable(u8, self, right_write);
// Internal Display Memory behaves differently on 8-bit reads
self.fillWriteTable(u32, write_tables[0]);
self.fillWriteTable(u8, write_tables[1]);
}
pub fn deinit(self: *Self) void {
@@ -106,50 +102,50 @@ pub fn deinit(self: *Self) void {
self.* = undefined;
}
fn fillReadTable(bus: *Self, table: *[table_len]?*const anyopaque) void {
fn fillReadTable(self: *Self, table: *[table_len]?*const anyopaque) void {
const vramMirror = @import("ppu/Vram.zig").mirror;
for (table) |*ptr, i| {
const addr = page_size * i;
const addr = @intCast(u32, page_size * i);
ptr.* = switch (addr) {
// General Internal Memory
0x0000_0000...0x0000_3FFF => null, // BIOS has it's own checks
0x0200_0000...0x02FF_FFFF => &bus.ewram.buf[addr & 0x3FFFF],
0x0300_0000...0x03FF_FFFF => &bus.iwram.buf[addr & 0x7FFF],
0x0200_0000...0x02FF_FFFF => &self.ewram.buf[addr & 0x3FFFF],
0x0300_0000...0x03FF_FFFF => &self.iwram.buf[addr & 0x7FFF],
0x0400_0000...0x0400_03FF => null, // I/O
// Internal Display Memory
0x0500_0000...0x05FF_FFFF => &bus.ppu.palette.buf[addr & 0x3FF],
0x0600_0000...0x06FF_FFFF => &bus.ppu.vram.buf[vramMirror(addr)],
0x0700_0000...0x07FF_FFFF => &bus.ppu.oam.buf[addr & 0x3FF],
0x0500_0000...0x05FF_FFFF => &self.ppu.palette.buf[addr & 0x3FF],
0x0600_0000...0x06FF_FFFF => &self.ppu.vram.buf[vramMirror(addr)],
0x0700_0000...0x07FF_FFFF => &self.ppu.oam.buf[addr & 0x3FF],
// External Memory (Game Pak)
0x0800_0000...0x0DFF_FFFF => fillTableExternalMemory(bus, addr),
0x0800_0000...0x0DFF_FFFF => self.fillReadTableExternal(addr),
0x0E00_0000...0x0FFF_FFFF => null, // SRAM
else => null,
};
}
}
fn fillWriteTable(comptime T: type, bus: *Self, table: *[table_len]?*const anyopaque) void {
fn fillWriteTable(self: *Self, comptime T: type, table: *[table_len]?*const anyopaque) void {
comptime std.debug.assert(T == u32 or T == u16 or T == u8);
const vramMirror = @import("ppu/Vram.zig").mirror;
for (table) |*ptr, i| {
const addr = page_size * i;
const addr = @intCast(u32, page_size * i);
ptr.* = switch (addr) {
// General Internal Memory
0x0000_0000...0x0000_3FFF => null, // BIOS has it's own checks
0x0200_0000...0x02FF_FFFF => &bus.ewram.buf[addr & 0x3FFFF],
0x0300_0000...0x03FF_FFFF => &bus.iwram.buf[addr & 0x7FFF],
0x0200_0000...0x02FF_FFFF => &self.ewram.buf[addr & 0x3FFFF],
0x0300_0000...0x03FF_FFFF => &self.iwram.buf[addr & 0x7FFF],
0x0400_0000...0x0400_03FF => null, // I/O
// Internal Display Memory
0x0500_0000...0x05FF_FFFF => if (T != u8) &bus.ppu.palette.buf[addr & 0x3FF] else null,
0x0600_0000...0x06FF_FFFF => if (T != u8) &bus.ppu.vram.buf[vramMirror(addr)] else null,
0x0700_0000...0x07FF_FFFF => if (T != u8) &bus.ppu.oam.buf[addr & 0x3FF] else null,
0x0500_0000...0x05FF_FFFF => if (T != u8) &self.ppu.palette.buf[addr & 0x3FF] else null,
0x0600_0000...0x06FF_FFFF => if (T != u8) &self.ppu.vram.buf[vramMirror(addr)] else null,
0x0700_0000...0x07FF_FFFF => if (T != u8) &self.ppu.oam.buf[addr & 0x3FF] else null,
// External Memory (Game Pak)
0x0800_0000...0x0DFF_FFFF => null, // ROM
@@ -159,24 +155,29 @@ fn fillWriteTable(comptime T: type, bus: *Self, table: *[table_len]?*const anyop
}
}
fn fillTableExternalMemory(bus: *Self, addr: usize) ?*anyopaque {
fn fillReadTableExternal(self: *Self, addr: u32) ?*anyopaque {
// see `GamePak.zig` for more information about what conditions need to be true
// so that a simple pointer dereference isn't possible
std.debug.assert(addr & @as(u32, page_size - 1) == 0); // addr is guaranteed to be page-aligned
const start_addr = addr;
const end_addr = addr + page_size;
const end_addr = start_addr + page_size;
const gpio_data = start_addr <= 0x0800_00C4 and 0x0800_00C4 < end_addr;
const gpio_direction = start_addr <= 0x0800_00C6 and 0x0800_00C6 < end_addr;
const gpio_control = start_addr <= 0x0800_00C8 and 0x0800_00C8 < end_addr;
{
const data = start_addr <= 0x0800_00C4 and 0x0800_00C4 < end_addr; // GPIO Data
const direction = start_addr <= 0x0800_00C6 and 0x0800_00C6 < end_addr; // GPIO Direction
const control = start_addr <= 0x0800_00C8 and 0x0800_00C8 < end_addr; // GPIO Control
if (bus.pak.gpio.device.kind != .None and (gpio_data or gpio_direction or gpio_control)) {
// We found a GPIO device, and this page a GPIO register. We want to handle this in slowmem
return null;
const has_gpio = data or direction or control;
const gpio_kind = self.pak.gpio.device.kind;
// There is a GPIO Device, and the current page contains at least one memory-mapped GPIO register
if (gpio_kind != .None and has_gpio) return null;
}
if (bus.pak.backup.kind == .Eeprom) {
if (bus.pak.buf.len > 0x100_000) {
if (self.pak.backup.kind == .Eeprom) {
if (self.pak.buf.len > 0x100_000) {
// We are using a "large" EEPROM which means that if the below check is true
// this page has an address that's reserved for the EEPROM and therefore must
// be handled in slowmem
@@ -192,9 +193,9 @@ fn fillTableExternalMemory(bus: *Self, addr: usize) ?*anyopaque {
// Finally, the GamePak has some unique behaviour for reads past the end of the ROM,
// so those will be handled by slowmem as well
const masked_addr = addr & 0x1FF_FFFF;
if (masked_addr >= bus.pak.buf.len) return null;
if (masked_addr >= self.pak.buf.len) return null;
return &bus.pak.buf[masked_addr];
return &self.pak.buf[masked_addr];
}
pub fn dbgRead(self: *const Self, comptime T: type, unaligned_address: u32) T {
@@ -208,8 +209,7 @@ pub fn dbgRead(self: *const Self, comptime T: type, unaligned_address: u32) T {
if (self.read_table[page]) |some_ptr| {
// We have a pointer to a page, cast the pointer to it's underlying type
const Ptr = [*]const T;
const alignment = @alignOf(std.meta.Child(Ptr));
const ptr = @ptrCast(Ptr, @alignCast(alignment, some_ptr));
const ptr = @ptrCast(Ptr, @alignCast(@alignOf(std.meta.Child(Ptr)), some_ptr));
// Note: We don't check array length, since we force align the
// lower bits of the address as the GBA would
@@ -326,8 +326,7 @@ pub fn read(self: *Self, comptime T: type, unaligned_address: u32) T {
if (self.read_table[page]) |some_ptr| {
// We have a pointer to a page, cast the pointer to it's underlying type
const Ptr = [*]const T;
const alignment = @alignOf(std.meta.Child(Ptr));
const ptr = @ptrCast(Ptr, @alignCast(alignment, some_ptr));
const ptr = @ptrCast(Ptr, @alignCast(@alignOf(std.meta.Child(Ptr)), some_ptr));
// Note: We don't check array length, since we force align the
// lower bits of the address as the GBA would
@@ -394,8 +393,7 @@ pub fn write(self: *Self, comptime T: type, unaligned_address: u32, value: T) vo
if (self.write_tables[@boolToInt(T == u8)][page]) |some_ptr| {
// We have a pointer to a page, cast the pointer to it's underlying type
const Ptr = [*]T;
const alignment = @alignOf(std.meta.Child(Ptr));
const ptr = @ptrCast(Ptr, @alignCast(alignment, some_ptr));
const ptr = @ptrCast(Ptr, @alignCast(@alignOf(std.meta.Child(Ptr)), some_ptr));
// Note: We don't check array length, since we force align the
// lower bits of the address as the GBA would
@@ -408,8 +406,9 @@ pub fn write(self: *Self, comptime T: type, unaligned_address: u32, value: T) vo
}
}
pub fn slowWrite(self: *Self, comptime T: type, unaligned_address: u32, value: T) void {
// @setCold(true);
fn slowWrite(self: *Self, comptime T: type, unaligned_address: u32, value: T) void {
@setCold(true);
const page = @truncate(u8, unaligned_address >> 24);
const address = forceAlign(T, unaligned_address);

2
src/core/emu.zig
View File

@@ -94,7 +94,7 @@ pub fn runFrame(sched: *Scheduler, cpu: *Arm7tdmi) void {
if (!cpu.stepDmaTransfer()) {
if (cpu.isHalted()) {
// Fast-forward to next Event
sched.tick = sched.queue.peek().?.tick;
sched.tick = sched.nextTimestamp();
} else {
cpu.step();
}

82
src/core/scheduler.zig
View File

@@ -31,61 +31,55 @@ pub const Scheduler = struct {
}
pub fn handleEvent(self: *Self, cpu: *Arm7tdmi) void {
if (self.queue.removeOrNull()) |event| {
const late = self.tick - event.tick;
const event = self.queue.remove();
const late = self.tick - event.tick;
switch (event.kind) {
.HeatDeath => {
log.err("u64 overflow. This *actually* should never happen.", .{});
unreachable;
},
.Draw => {
// The end of a VDraw
cpu.bus.ppu.drawScanline();
cpu.bus.ppu.onHdrawEnd(cpu, late);
},
.TimerOverflow => |id| {
switch (id) {
inline 0...3 => |idx| cpu.bus.tim[idx].onTimerExpire(cpu, late),
}
},
.ApuChannel => |id| {
switch (id) {
0 => cpu.bus.apu.ch1.onToneSweepEvent(late),
1 => cpu.bus.apu.ch2.onToneEvent(late),
2 => cpu.bus.apu.ch3.onWaveEvent(late),
3 => cpu.bus.apu.ch4.onNoiseEvent(late),
}
},
.RealTimeClock => {
const device = &cpu.bus.pak.gpio.device;
if (device.kind != .Rtc or device.ptr == null) return;
switch (event.kind) {
.HeatDeath => {
log.err("u64 overflow. This *actually* should never happen.", .{});
unreachable;
},
.Draw => {
// The end of a VDraw
cpu.bus.ppu.drawScanline();
cpu.bus.ppu.onHdrawEnd(cpu, late);
},
.TimerOverflow => |id| {
switch (id) {
inline 0...3 => |idx| cpu.bus.tim[idx].onTimerExpire(cpu, late),
}
},
.ApuChannel => |id| {
switch (id) {
0 => cpu.bus.apu.ch1.onToneSweepEvent(late),
1 => cpu.bus.apu.ch2.onToneEvent(late),
2 => cpu.bus.apu.ch3.onWaveEvent(late),
3 => cpu.bus.apu.ch4.onNoiseEvent(late),
}
},
.RealTimeClock => {
const device = &cpu.bus.pak.gpio.device;
if (device.kind != .Rtc or device.ptr == null) return;
const clock = @ptrCast(*Clock, @alignCast(@alignOf(*Clock), device.ptr.?));
clock.onClockUpdate(late);
},
.FrameSequencer => cpu.bus.apu.onSequencerTick(late),
.SampleAudio => cpu.bus.apu.sampleAudio(late),
.HBlank => cpu.bus.ppu.onHblankEnd(cpu, late), // The end of a HBlank
.VBlank => cpu.bus.ppu.onHdrawEnd(cpu, late), // The end of a VBlank
}
const clock = @ptrCast(*Clock, @alignCast(@alignOf(*Clock), device.ptr.?));
clock.onClockUpdate(late);
},
.FrameSequencer => cpu.bus.apu.onSequencerTick(late),
.SampleAudio => cpu.bus.apu.sampleAudio(late),
.HBlank => cpu.bus.ppu.onHblankEnd(cpu, late), // The end of a HBlank
.VBlank => cpu.bus.ppu.onHdrawEnd(cpu, late), // The end of a VBlank
}
}
/// Removes the **first** scheduled event of type `needle`
pub fn removeScheduledEvent(self: *Self, needle: EventKind) void {
var it = self.queue.iterator();
var i: usize = 0;
while (it.next()) |event| : (i += 1) {
for (self.queue.items) |event, i| {
if (std.meta.eql(event.kind, needle)) {
// This invalidates the iterator
// invalidates the slice we're iterating over
_ = self.queue.removeIndex(i);
// Since removing something from the PQ invalidates the iterator,
// this implementation can safely only remove the first instance of
// a Scheduled Event. Exit Early
log.debug("Removed {?}@{}", .{ event.kind, event.tick });
break;
}
}