chore: give DISPCNT DISPSTAT and VCOUNT to PPU struct

This commit is contained in:
Rekai Nyangadzayi Musuka 2022-02-13 04:27:20 -04:00
parent 31fa06ac4a
commit e5a76a3c02
3 changed files with 73 additions and 76 deletions

View File

@ -7,60 +7,15 @@ const Bus = @import("../Bus.zig");
pub const Io = struct {
const Self = @This();
dispcnt: DisplayControl,
dispstat: DisplayStatus,
vcount: VCount,
/// Read / Write
bg0cnt: BackgroundControl,
/// Read / Write
bg1cnt: BackgroundControl,
/// Read / Write
bg2cnt: BackgroundControl,
/// Read / Write
bg3cnt: BackgroundControl,
/// Write Only
bg0hofs: BackgroundOffset,
/// Write Only
bg0vofs: BackgroundOffset,
/// Write Only
bg1hofs: BackgroundOffset,
/// Write Only
bg1vofs: BackgroundOffset,
/// Write Only
bg2hofs: BackgroundOffset,
/// Write Only
bg2vofs: BackgroundOffset,
/// Write Only
bg3hofs: BackgroundOffset,
/// Write Only
bg3vofs: BackgroundOffset,
/// Read / Write
ime: bool,
ie: InterruptEnable,
/// Read / Write
irq: InterruptRequest,
keyinput: KeyInput,
pub fn init() Self {
return .{
.dispcnt = .{ .raw = 0x0000 },
.dispstat = .{ .raw = 0x0000 },
.vcount = .{ .raw = 0x0000 },
.bg0cnt = .{ .raw = 0x0000 },
.bg1cnt = .{ .raw = 0x0000 },
.bg2cnt = .{ .raw = 0x0000 },
.bg3cnt = .{ .raw = 0x0000 },
.bg0hofs = .{ .raw = 0x0000 },
.bg0vofs = .{ .raw = 0x0000 },
.bg1hofs = .{ .raw = 0x0000 },
.bg1vofs = .{ .raw = 0x0000 },
.bg2hofs = .{ .raw = 0x0000 },
.bg2vofs = .{ .raw = 0x0000 },
.bg3hofs = .{ .raw = 0x0000 },
.bg3vofs = .{ .raw = 0x0000 },
.ime = false,
.ie = .{ .raw = 0x0000 },
.irq = .{ .raw = 0x0000 },
@ -70,7 +25,7 @@ pub const Io = struct {
};
/// Read / Write
const DisplayControl = extern union {
pub const DisplayControl = extern union {
bg_mode: Bitfield(u16, 0, 3),
frame_select: Bit(u16, 4),
hblank_interval_free: Bit(u16, 5),
@ -84,7 +39,7 @@ const DisplayControl = extern union {
};
/// Read / Write
const DisplayStatus = extern union {
pub const DisplayStatus = extern union {
vblank: Bit(u16, 0),
hblank: Bit(u16, 1),
coincidence: Bit(u16, 2),
@ -96,7 +51,7 @@ const DisplayStatus = extern union {
};
/// Read Only
const VCount = extern union {
pub const VCount = extern union {
scanline: Bitfield(u16, 0, 8),
raw: u16,
};
@ -136,7 +91,8 @@ const KeyInput = extern union {
raw: u16,
};
const BackgroundControl = extern union {
// Read / Write
pub const BackgroundControl = extern union {
bg_priority: Bitfield(u16, 0, 2),
char_base: Bitfield(u16, 2, 2),
mosaic_enable: Bit(u16, 6),
@ -147,11 +103,13 @@ const BackgroundControl = extern union {
raw: u16,
};
const BackgroundOffset = extern union {
/// Write Only
pub const BackgroundOffset = extern union {
offset: Bitfield(u16, 0, 9),
raw: u16,
};
/// Read / Write
const InterruptRequest = extern union {
vblank: Bit(u16, 0),
hblank: Bit(u16, 1),
@ -172,9 +130,9 @@ const InterruptRequest = extern union {
pub fn read32(bus: *const Bus, addr: u32) u32 {
return switch (addr) {
0x0400_0000 => bus.io.dispcnt.raw,
0x0400_0004 => bus.io.dispstat.raw,
0x0400_0006 => bus.io.vcount.raw,
0x0400_0000 => bus.ppu.dispcnt.raw,
0x0400_0004 => bus.ppu.dispstat.raw,
0x0400_0006 => bus.ppu.vcount.raw,
0x0400_0200 => bus.io.ie.raw,
0x0400_0208 => @boolToInt(bus.io.ime),
else => std.debug.panic("[I/O:32] tried to read from {X:}", .{addr}),
@ -183,7 +141,7 @@ pub fn read32(bus: *const Bus, addr: u32) u32 {
pub fn write32(bus: *Bus, addr: u32, word: u32) void {
switch (addr) {
0x0400_0000 => bus.io.dispcnt.raw = @truncate(u16, word),
0x0400_0000 => bus.ppu.dispcnt.raw = @truncate(u16, word),
0x0400_0200 => bus.io.ie.raw = @truncate(u16, word),
0x0400_0208 => bus.io.ime = word & 1 == 1,
else => std.debug.panic("[I/O:32] tried to write 0x{X:} to 0x{X:}", .{ word, addr }),
@ -192,9 +150,9 @@ pub fn write32(bus: *Bus, addr: u32, word: u32) void {
pub fn read16(bus: *const Bus, addr: u32) u16 {
return switch (addr) {
0x0400_0000 => bus.io.dispcnt.raw,
0x0400_0004 => bus.io.dispstat.raw,
0x0400_0006 => bus.io.vcount.raw,
0x0400_0000 => bus.ppu.dispcnt.raw,
0x0400_0004 => bus.ppu.dispstat.raw,
0x0400_0006 => bus.ppu.vcount.raw,
0x0400_0130 => bus.io.keyinput.raw,
0x0400_0200 => bus.io.ie.raw,
0x0400_0208 => @boolToInt(bus.io.ime),
@ -204,11 +162,11 @@ pub fn read16(bus: *const Bus, addr: u32) u16 {
pub fn write16(bus: *Bus, addr: u32, halfword: u16) void {
switch (addr) {
0x0400_0000 => bus.io.dispcnt.raw = halfword,
0x0400_0004 => bus.io.dispstat.raw = halfword,
0x0400_0008 => bus.io.bg0cnt.raw = halfword,
0x0400_0010 => bus.io.bg0hofs.raw = halfword,
0x0400_0012 => bus.io.bg0vofs.raw = halfword,
0x0400_0000 => bus.ppu.dispcnt.raw = halfword,
0x0400_0004 => bus.ppu.dispstat.raw = halfword,
0x0400_0008 => bus.ppu.bg0.cnt.raw = halfword,
0x0400_0010 => bus.ppu.bg0.hofs.raw = halfword,
0x0400_0012 => bus.ppu.bg0.vofs.raw = halfword,
0x0400_0200 => bus.io.ie.raw = halfword,
0x0400_0202 => bus.io.irq.raw = halfword,
0x0400_0208 => bus.io.ime = halfword & 1 == 1,
@ -218,10 +176,10 @@ pub fn write16(bus: *Bus, addr: u32, halfword: u16) void {
pub fn read8(bus: *const Bus, addr: u32) u8 {
return switch (addr) {
0x0400_0000 => @truncate(u8, bus.io.dispcnt.raw),
0x0400_0004 => @truncate(u8, bus.io.dispstat.raw),
0x0400_0000 => @truncate(u8, bus.ppu.dispcnt.raw),
0x0400_0004 => @truncate(u8, bus.ppu.dispstat.raw),
0x0400_0200 => @truncate(u8, bus.io.ie.raw),
0x0400_0006 => @truncate(u8, bus.io.vcount.raw),
0x0400_0006 => @truncate(u8, bus.ppu.vcount.raw),
else => std.debug.panic("[I/O:8] tried to read from {X:}", .{addr}),
};
}

View File

@ -1,10 +1,11 @@
const std = @import("std");
const io = @import("bus/io.zig");
const EventKind = @import("scheduler.zig").EventKind;
const Io = @import("bus/io.zig").Io;
const Scheduler = @import("scheduler.zig").Scheduler;
const Allocator = std.mem.Allocator;
pub const width = 240;
pub const height = 160;
pub const framebuf_pitch = width * @sizeOf(u16);
@ -12,6 +13,16 @@ pub const framebuf_pitch = width * @sizeOf(u16);
pub const Ppu = struct {
const Self = @This();
// Registers
bg0: Background,
bg1: Background,
bg2: Background,
bg3: Background,
dispcnt: io.DisplayControl,
dispstat: io.DisplayStatus,
vcount: io.VCount,
vram: Vram,
palette: Palette,
oam: Oam,
@ -33,6 +44,15 @@ pub const Ppu = struct {
.sched = sched,
.framebuf = framebuf,
.alloc = alloc,
// Registers
.bg0 = Background.init(),
.bg1 = Background.init(),
.bg2 = Background.init(),
.bg3 = Background.init(),
.dispcnt = .{ .raw = 0x0000 },
.dispstat = .{ .raw = 0x0000 },
.vcount = .{ .raw = 0x0000 },
};
}
@ -42,9 +62,9 @@ pub const Ppu = struct {
self.palette.deinit();
}
pub fn drawScanline(self: *Self, io: *const Io) void {
const bg_mode = io.dispcnt.bg_mode.read();
const scanline = io.vcount.scanline.read();
pub fn drawScanline(self: *Self) void {
const bg_mode = self.dispcnt.bg_mode.read();
const scanline = self.vcount.scanline.read();
switch (bg_mode) {
0x0 => {
@ -58,7 +78,7 @@ pub const Ppu = struct {
std.mem.copy(u8, self.framebuf[start..end], self.vram.buf[start..end]);
},
0x4 => {
const select = io.dispcnt.frame_select.read();
const select = self.dispcnt.frame_select.read();
const vram_start = width * @as(usize, scanline);
const buf_start = vram_start * @sizeOf(u16);
@ -205,3 +225,22 @@ const Oam = struct {
return self.buf[idx];
}
};
const Background = struct {
const Self = @This();
/// Read / Write
cnt: io.BackgroundControl,
/// Write Only
hofs: io.BackgroundOffset,
/// Write Only
vofs: io.BackgroundOffset,
fn init() Self {
return .{
.cnt = .{ .raw = 0x0000 },
.hofs = .{ .raw = 0x0000 },
.vofs = .{ .raw = 0x0000 },
};
}
};

View File

@ -38,28 +38,28 @@ pub const Scheduler = struct {
},
.HBlank => {
// The End of a Hblank (During Draw or Vblank)
const old_scanline = bus.io.vcount.scanline.read();
const old_scanline = bus.ppu.vcount.scanline.read();
const scanline = (old_scanline + 1) % 228;
bus.io.vcount.scanline.write(scanline);
bus.io.dispstat.hblank.unset();
bus.ppu.vcount.scanline.write(scanline);
bus.ppu.dispstat.hblank.unset();
if (scanline < 160) {
// Transitioning to another Draw
self.push(.Draw, self.tick + (240 * 4));
} else {
// Transitioning to a Vblank
if (scanline < 227) bus.io.dispstat.vblank.set() else bus.io.dispstat.vblank.unset();
if (scanline < 227) bus.ppu.dispstat.vblank.set() else bus.ppu.dispstat.vblank.unset();
self.push(.VBlank, self.tick + (240 * 4));
}
},
.Draw => {
// The end of a Draw
bus.ppu.drawScanline(&bus.io);
bus.ppu.drawScanline();
// Transitioning to a Hblank
bus.io.dispstat.hblank.set();
bus.ppu.dispstat.hblank.set();
self.push(.HBlank, self.tick + (68 * 4));
},
.VBlank => {