README.md

@@ -1,36 +1,5 @@
-# TetrOS: bare-metal tetris
+- quick drop
-
+- faster timer
-## TODO:
+- fix asm loader
-- Fix stage 1 loader
+- document everything
-
+- prettier pictures
-## Features
-- Compiles to a standalone disk image
-- Written from scratch using only Nasm and Rust
-- Custom BIOS bootloader
-- 32-bit x86 OS
-- 🌟 Detailed comments. Read the [makefile](./Makefile), then start in [`./bios/main.asm`](./bios/main.asm).
-
-
-## Non-Features
-- Never tested on real hardware
-- Minimal gameplay and graphics. These features aren't hard to implement, but also don't present any interesting challenges. I have other things to do.
-
-
-## 🚀 Building and Running
-- All scripts are in the [makefile](./Makefile).
-- To build and run, use `make qemu`.
-  - Dependencies: `nasm`, `cargo`, GNU `binutils`, `qemu`
-  - This will NOT work on MacOS. BSD `ld` does not work like GNU `ld`.
-- Alternatively, a compiled disk image for the latest commit is [here](https://git.betalupi.com/api/packages/Mark/generic/tetros/latest/disk.img). This is the same file produced by `make`.
-  - Download it and run `qemu-system-i386 -d cpu_reset -no-reboot -smp 1 -m 2048 -machine q35 -net none -serial stdio -fda "disk.img"`
-
-
-## 📜 Resources
-**Used directly:**
-- [jdh's video](https://www.youtube.com/watch?v=FaILnmUYS_U)
-- [The OSDev wiki](https://wiki.osdev.org/Main_Page)
-- [RedoxOS bootloader](https://gitlab.redox-os.org/redox-os/bootloader)
-
-**Useful background knowledge:**
-- [Writing an OS in Rust](https://os.phil-opp.com)
-- [Operating Systems: From 0 to 1](https://github.com/tuhdo/os01)

bios/cpuid.asm

@@ -0,0 +1,176 @@
+SECTION .text
+USE16
+
+cpuid_required_features:
+    .edx equ cpuid_edx.fpu | cpuid_edx.pse | cpuid_edx.pge | cpuid_edx.fxsr
+    .ecx equ 0
+
+cpuid_check:
+    ; If bit 21 of EFLAGS can be changed, then CPUID is supported
+    pushfd                               ;Save EFLAGS
+    pushfd                               ;Store EFLAGS
+    xor dword [esp],0x00200000           ;Invert the ID bit in stored EFLAGS
+    popfd                                ;Load stored EFLAGS (with ID bit inverted)
+    pushfd                               ;Store EFLAGS again (ID bit may or may not be inverted)
+    pop eax                              ;eax = modified EFLAGS (ID bit may or may not be inverted)
+    xor eax,[esp]                        ;eax = whichever bits were changed
+    popfd                                ;Restore original EFLAGS
+    test eax,0x00200000                  ;eax = zero if ID bit can't be changed, else non-zero
+    jz .no_cpuid
+
+    mov eax, 1
+    cpuid
+
+    and edx, cpuid_required_features.edx
+    cmp edx, cpuid_required_features.edx
+    jne .error
+
+    and ecx, cpuid_required_features.ecx
+    cmp ecx, cpuid_required_features.ecx
+    jne .error
+
+    ret
+
+.no_cpuid:
+    mov si, .msg_cpuid
+    call print
+
+    mov si, .msg_line
+    call print
+
+    jmp .halt
+
+.error:
+    push ecx
+    push edx
+
+    mov si, .msg_features
+    call print
+
+    mov si, .msg_line
+    call print
+
+    mov si, .msg_edx
+    call print
+
+    pop ebx
+    push ebx
+    shr ebx, 16
+    call print_hex
+
+    pop ebx
+    call print_hex
+
+    mov si, .msg_must_contain
+    call print
+
+    mov ebx, cpuid_required_features.edx
+    shr ebx, 16
+    call print_hex
+
+    mov ebx, cpuid_required_features.edx
+    call print_hex
+
+    mov si, .msg_line
+    call print
+
+    mov si, .msg_ecx
+    call print
+
+    pop ebx
+    push ebx
+    shr ebx, 16
+    call print_hex
+
+    pop ebx
+    call print_hex
+
+    mov si, .msg_must_contain
+    call print
+
+    mov ebx, cpuid_required_features.ecx
+    shr ebx, 16
+    call print_hex
+
+    mov ebx, cpuid_required_features.ecx
+    call print_hex
+
+    mov si, .msg_line
+    call print
+
+.halt:
+    cli
+    hlt
+    jmp .halt
+
+.msg_cpuid: db "CPUID not supported",0
+.msg_features: db "Required CPU features are not present",0
+.msg_line: db 13,10,0
+.msg_edx: db "EDX ",0
+.msg_ecx: db "ECX ",0
+.msg_must_contain: db " must contain ",0
+
+cpuid_edx:
+    .fpu                 equ 1 << 0
+    .vme                 equ 1 << 1
+    .de                  equ 1 << 2
+    .pse                 equ 1 << 3
+    .tsc                 equ 1 << 4
+    .msr                 equ 1 << 5
+    .pae                 equ 1 << 6
+    .mce                 equ 1 << 7
+    .cx8                 equ 1 << 8
+    .apic                equ 1 << 9
+    .sep                 equ 1 << 11
+    .mtrr                equ 1 << 12
+    .pge                 equ 1 << 13
+    .mca                 equ 1 << 14
+    .cmov                equ 1 << 15
+    .pat                 equ 1 << 16
+    .pse_36              equ 1 << 17
+    .psn                 equ 1 << 18
+    .clfsh               equ 1 << 19
+    .ds                  equ 1 << 21
+    .acpi                equ 1 << 22
+    .mmx                 equ 1 << 23
+    .fxsr                equ 1 << 24
+    .sse                 equ 1 << 25
+    .sse2                equ 1 << 26
+    .ss                  equ 1 << 27
+    .htt                 equ 1 << 28
+    .tm                  equ 1 << 29
+    .ia64                equ 1 << 30
+    .pbe                 equ 1 << 31
+
+cpuid_ecx:
+    .sse3                equ 1 << 0
+    .pclmulqdq           equ 1 << 1
+    .dtes64              equ 1 << 2
+    .monitor             equ 1 << 3
+    .ds_cpl              equ 1 << 4
+    .vmx                 equ 1 << 5
+    .smx                 equ 1 << 6
+    .est                 equ 1 << 7
+    .tm2                 equ 1 << 8
+    .ssse3               equ 1 << 9
+    .cnxt_id             equ 1 << 10
+    .sdbg                equ 1 << 11
+    .fma                 equ 1 << 12
+    .cmpxchg16b          equ 1 << 13
+    .xtpr                equ 1 << 14
+    .pdcm                equ 1 << 15
+    .pcid                equ 1 << 17
+    .dca                 equ 1 << 18
+    .sse4_1              equ 1 << 19
+    .sse4_2              equ 1 << 20
+    .x2apic              equ 1 << 21
+    .movbe               equ 1 << 22
+    .popcnt              equ 1 << 23
+    .tsc_deadline        equ 1 << 24
+    .aes                 equ 1 << 25
+    .xsave               equ 1 << 26
+    .osxsave             equ 1 << 27
+    .avx                 equ 1 << 28
+    .f16c                equ 1 << 29
+    .rdrand              equ 1 << 30
+    .hypervisor          equ 1 << 31

bios/stage2.asm

@@ -8,6 +8,10 @@ stage2.entry:
     call print_char
     call print_line
 
+
+    ; check for required features
+    call cpuid_check
+
     ; enable A20-Line via IO-Port 92, might not work on all motherboards
     in al, 0x92
     or al, 2
@@ -16,6 +20,7 @@ stage2.entry:
     mov dword [protected_mode.func], stage3.entry
     jmp protected_mode.entry
 
+%include "cpuid.asm"
 %include "gdt.asm"
 %include "protected_mode.asm"
 %include "thunk.asm"

tetros/src/game/falling.rs

@@ -62,7 +62,6 @@ impl Direction {
 		}
 	}
 
-	/*
 	pub fn rot_ccw(self) -> Self {
 		match self {
 			Self::North => Self::West,
@@ -71,7 +70,6 @@ impl Direction {
 			Self::East => Self::North,
 		}
 	}
-	*/
 }
 
 #[derive(Debug, Clone)]
@@ -126,11 +124,9 @@ impl FallingTetromino {
 		self.direction = self.direction.rot_cw()
 	}
 
-	/*
 	pub fn rotate_ccw(&mut self) {
 		self.direction = self.direction.rot_ccw()
 	}
-	*/
 
 	/// Returns the positions of this falling tetromino's tiles.
 	pub fn tiles(&self) -> [(usize, usize); 4] {

tetros/src/lib.rs

@@ -205,14 +205,12 @@ pub unsafe extern "C" fn start(thunk10: extern "C" fn()) -> ! {
 						};
 					}
 
-					Some(InputKey::Down) => loop {
+					Some(InputKey::Down) => {
-						fall_test.translate(0, 1);
+						fall_test.rotate_ccw();
 						if board.tetromino_valid(&fall_test) {
-							fall.translate(0, 1);
+							fall.rotate_ccw()
-						} else {
+						};
-							break;
+					}
-						}
-					},
 
 					Some(InputKey::Left) => {
 						fall_test.translate(-1, 0);
@@ -246,7 +244,7 @@ pub unsafe extern "C" fn start(thunk10: extern "C" fn()) -> ! {
 			board.draw(&mut v, fall.as_ref());
 
 			if let Some(fall_inner) = fall.as_mut() {
-				if t % 4 == 0 {
+				if t % 5 == 0 {
 					let mut fall_test = fall_inner.clone();
 					fall_test.translate(0, 1);
 
@@ -260,10 +258,7 @@ pub unsafe extern "C" fn start(thunk10: extern "C" fn()) -> ! {
 					}
 				}
 			} else {
-				*fall = Some(FallingTetromino::random(5, 1));
+				*fall = Some(FallingTetromino::random(5, 1))
-				if !board.tetromino_valid(fall.as_ref().unwrap()) {
-					panic!("\nGAME OVER");
-				}
 			}
 		})
 	}