prepare for transplanting of new shade into shade64 base

Makefile

@@ -1,7 +1,7 @@
 ASM ?= nasm
-CC := i686-elf-gcc
-GDB := i686-elf-gdb
-LD := i686-elf-ld
+CC := x86_64-elf-gcc
+GDB := gdb
+LD := x86_64-elf-ld
 
 C_FILES = $(shell find src/ -type f -name '*.c')
 CO_FILES = $(patsubst src/%.c, obj/%.o, $(C_FILES))
@@ -10,15 +10,15 @@ AO_FILES = $(patsubst src/kernel/%.asm, obj/kernel/%.o, $(ASM_FILES))
 
 KERNEL_O_FILES = ${CO_FILES} ${AO_FILES}
 
+BOOT_O_FILES = obj/entry.o obj/entry64.o obj/mb2.o obj/vga-print.o
+BOOT_SRC_FILES = obj/entry.asm obj/entry64.asm obj/mb2.asm obj/vga-print.asm
+
 iso: bin/shade.iso
 
-obj/boot.o: src/boot.asm
-	$(ASM) -felf32 $^ -o $@
-
-bin/shade.bin: obj/boot.o ${KERNEL_O_FILES}
+bin/shade.bin: ${BOOT_O_FILES} ${KERNEL_O_FILES}
 	mkdir -p bin
-	$(CC) -T src/linker.ld -ffreestanding -O2 -nostdlib $^ -o $@ -lgcc
-	grub-file --is-x86-multiboot bin/shade.bin
+	$(LD) -T src/linker.ld $^ -o $@
+	grub-file --is-x86-multiboot2 bin/shade.bin
 
 bin/shade.iso: bin/shade.bin
 	mkdir -p isodir/boot/grub
@@ -33,7 +33,7 @@ obj/%.o: src/%.c
 
 obj/%.o: src/%.asm
 	mkdir -p "$(@D)"
-	$(ASM) -f elf $< -o $@
+	$(ASM) -f elf64 $< -o $@
 
 
 run: clean bin/shade.iso

src/boot.asm

@@ -1,52 +0,0 @@
-; Declare constants for the multiboot header.
-MBALIGN  equ  1 << 0            ; align loaded modules on page boundaries
-MEMINFO  equ  1 << 1            ; provide memory map
-FLAGS    equ  MBALIGN | MEMINFO ; this is the Multiboot 'flag' field
-MAGIC    equ  0x1BADB002        ; 'magic number' lets bootloader find the header
-CHECKSUM equ -(MAGIC + FLAGS)   ; checksum of above, to prove we are multiboot
-
-section .multiboot
-align 4
-    dd MAGIC
-	dd FLAGS
-	dd CHECKSUM
-
-section .bss
-align 16
-
-stack_bottom:
-resb 16384
-stack_top:
-
-%include "src/gdt.asm"
-
-; _start = entry to kernel
-; Since the bootloader will be gone, it doesn't make sense to return from this
-section .text
-
-global _start:function (_start.end - _start)
-_start:
-    ; 32bit protected mode, no int, no paging
-    mov esp, stack_top ; Initialize stack
-
-    cli ; Disable interrupts
-    lgdt [gdt_descriptor] ; load the GDT
-    jmp CODE_SEG:.reload_seg ; far jump into a different segment
-
-.reload_seg: ; now in 32bit
-    mov ax, DATA_SEG ; update segment registers
-    mov ds, ax
-    mov ss, ax
-    mov es, ax
-    mov fs, ax
-    mov gs, ax
-
-    extern kmain
-    call kmain
-
-    cli ; Turn off interrupts in case they are on
-.hang:
-    hlt ; Totally halt the cpu
-    jmp .hang ; If the cpu un-halts for some reason, halt again
-
-.end:

src/gdt.asm

@@ -1,33 +0,0 @@
-section .data
-
-gdt_start: ; use labels to compute sizes and jumps
-    ; gdt starts with 8 byte null
-    dd 0x0
-    dd 0x0
-
-; GDT for code segment, base = 0x00000000, length = 0xfffff
-gdt_code:
-    dw 0xffff ; segment length
-    dw 0x0 ; segment base
-    db 0x0 ; segment base
-    db 10011010b ; flags
-    db 11001111b ; flags + segment length
-    db 0x0 ; segment base
-
-; GDT for data segment
-gdt_data:
-    dw 0xffff ; segment length
-    dw 0x0 ; segment base
-    db 0x0 ; segment base
-    db 10010010b ; flags
-    db 11001111b ; flags + segment length
-    db 0x0 ; segment base
-
-gdt_end:
-
-gdt_descriptor:
-    dw gdt_end - gdt_start - 1 ; size, always 1 less than what it actually is
-    dd gdt_start ; address
-
-CODE_SEG equ gdt_code - gdt_start
-DATA_SEG equ gdt_data - gdt_start

src/kernel/kernel.c

@@ -1,6 +1,5 @@
-#include "./platform/drivers/ports.h"
+#include "./platform/ports.h"
 #include "print.h"
-#include "./platform/interrupts/int.h"
 
 void dummy_test_entrypoint() {}
 
@@ -45,10 +44,4 @@ void kmain() {
     print_str("Copyright (c) e3team 2022. All rights reserved.\n");
     print_str("This program is provided \"as-is\" and no express or implied warranty is provided.\n");
     print_str("The full license can be found at /sys/LICENCE on this system or ./LICENCE in the source tree.\n");
-
-    idt_init();
-
-    __asm__ __volatile__("int $2");
-
-    //kernel_msg_ok("Interrupts working");
 }

src/kernel/platform/drivers/ports.c

@@ -1,26 +0,0 @@
-/*
- * Read 1 byte from specified port
- */
-unsigned char port_byte_in(unsigned short port) {
-    unsigned char result;
-    // source and dest are backwards.
-    // "=a (result)" set the C variable to the value of register e'a'x
-    // '"d" (port) map the C variable port into e'd'x register
-    __asm__("in %%dx, %%al" : "=a" (result) : "d" (port));
-}
-
-void port_byte_out(unsigned short port, unsigned char data) {
-    // both regs are C vars, nothing is returned, so no '=' in asm syntax
-    // comma because two vars in input area and none in return area
-    __asm__("out %%al, %%dx" : : "a" (data), "d" (port));
-}
-
-unsigned short port_word_in(unsigned short port) {
-    unsigned short result;
-    __asm__("in %%dx, %%ax" : "=a" (result) : "d" (port));
-    return result;
-}
-
-void port_word_out(unsigned short port, unsigned short data) {
-    __asm__("out %%ax, %%dx" : : "a" (data), "d" (port));
-}

src/kernel/platform/drivers/ports.h

@@ -1,4 +0,0 @@
-unsigned char port_byte_in(unsigned short port);
-void port_byte_out(unsigned short port, unsigned char data);
-unsigned short port_word_in(unsigned short port);
-void port_word_out(unsigned short port, unsigned short data);

src/kernel/platform/interrupts/int.c

@@ -1,35 +0,0 @@
-#include "int.h"
-#include "../../print.h"
-
-#include <stdbool.h>
-#include <stddef.h>
-#include <stdint.h>
-
-int count = 0;
-
-void exception_handler() {
-    print_str("I");
-}
-
-void idt_set_descriptor(uint8_t vector, void* isr, uint8_t flags) {
-    idt_entry_t* descriptor = &idt[vector];
- 
-    descriptor->isr_low        = (uint32_t)isr & 0xFFFF;
-    descriptor->kernel_cs      = 0x08; // this value can be whatever offset your kernel code selector is in your GDT
-    descriptor->attributes     = flags;
-    descriptor->isr_high       = (uint32_t)isr >> 16;
-    descriptor->reserved       = 0;
-}
-
-void idt_init() {
-    idtr.base = (uint32_t)&idt[0];
-    idtr.limit = (uint16_t)sizeof(idt_entry_t) * 256 - 1;
- 
-    for (uint8_t vector = 0; vector < 32; vector++) {
-        idt_set_descriptor(vector, isr_stub_table[vector], 0x8E);
-        isr_stub_table[vector] = true;
-    }
- 
-    __asm__ volatile ("lidt %0" : : "m"(idtr)); // load the new IDT
-    __asm__ volatile ("sti"); // set the interrupt flag
-}

src/kernel/platform/interrupts/int.h

@@ -1,43 +0,0 @@
-#ifndef INT_H
-#define INT_H
-
-#include "../../util.h"
-#include <stdbool.h>
-#include <stddef.h>
-#include <stdint.h>
-
-typedef struct {
-	uint16_t isr_low;      // The lower 16 bits of the ISR's address
-	uint16_t kernel_cs;    // The GDT segment selector that the CPU will load into CS before calling the ISR
-	uint8_t  reserved;     // Set to zero
-	uint8_t  attributes;   // Type and attributes; see the IDT page
-	uint16_t isr_high;     // The higher 16 bits of the ISR's address
-} __attribute__((packed)) idt_entry_t;
-
-__attribute__((aligned(0x10))) 
-static idt_entry_t idt[256]; // Create an array of IDT entries; aligned for performance
-
-typedef struct {
-	uint16_t	limit;
-	uint32_t	base;
-} __attribute__((packed)) idtr_t;
-
-static idtr_t idtr;
-
-typedef struct {
-   uint32_t ds; /* Data segment selector */
-   uint32_t edi, esi, ebp, esp, ebx, edx, ecx, eax; /* Pushed by pusha. */
-   uint32_t int_no, err_code; /* Interrupt number and error code (if applicable) */
-   uint32_t eip, cs, eflags, useresp, ss; /* Pushed by the processor automatically */
-} registers_t;
-
-__attribute__((noreturn))
-void exception_handler();
-
-void idt_set_descriptor(uint8_t vector, void* isr, uint8_t flags);
-
-extern void* isr_stub_table[];
- 
-void idt_init(void);
-
-#endif

src/kernel/platform/interrupts/int_lowlevel.asm

@@ -1,101 +0,0 @@
-%macro isr_err_stub 1
-isr_stub_%+%1:
-    ;push byte %1 ; Push interrupt no to stack
-
-    ; 1. Save CPU state
-	;pusha ; Pushes edi,esi,ebp,esp,ebx,edx,ecx,eax
-	;mov ax, ds ; Lower 16-bits of eax = ds.
-	;push eax ; save the data segment descriptor
-	;mov ax, 0x10  ; kernel data segment descriptor
-	;mov ds, ax
-	;mov es, ax
-	;mov fs, ax
-	;mov gs, ax
-	
-    ; 2. Call C handler
-	call exception_handler
-	
-    ; 3. Restore state
-	;pop eax 
-	;mov ds, ax
-	;mov es, ax
-	;mov fs, ax
-	;mov gs, ax
-	;popa
-	;add esp, 8 ; Cleans up the pushed error code and pushed ISR number
-	iret ; pops 5 things at once: CS, EIP, EFLAGS, SS, and ESP
-%endmacro
-; if writing for 64-bit, use iretq instead
-%macro isr_no_err_stub 1
-isr_stub_%+%1:
-    ;push byte 0  ; No error occured
-    ;push byte %1 ; Push interrupt no to stack
-    
-    ; 1. Save CPU state
-	;pusha ; Pushes edi,esi,ebp,esp,ebx,edx,ecx,eax
-	;mov ax, ds ; Lower 16-bits of eax = ds.
-	;push eax ; save the data segment descriptor
-	;mov ax, 0x10  ; kernel data segment descriptor
-	;mov ds, ax
-	;mov es, ax
-	;mov fs, ax
-	;mov gs, ax
-	
-    ; 2. Call C handler
-	call exception_handler
-	
-    ; 3. Restore state
-	;pop eax 
-	;mov ds, ax
-	;mov es, ax
-	;mov fs, ax
-	;mov gs, ax
-	;popa
-	;add esp, 8 ; Cleans up the pushed error code and pushed ISR number
-	;sti
-	iret ; pops 5 things at once: CS, EIP, EFLAGS, SS, and ESP
-%endmacro
-
-extern exception_handler
-
-isr_no_err_stub 0
-isr_no_err_stub 1
-isr_no_err_stub 2
-isr_no_err_stub 3
-isr_no_err_stub 4
-isr_no_err_stub 5
-isr_no_err_stub 6
-isr_no_err_stub 7
-isr_err_stub    8
-isr_no_err_stub 9
-isr_err_stub    10
-isr_err_stub    11
-isr_err_stub    12
-isr_err_stub    13
-isr_err_stub    14
-isr_no_err_stub 15
-isr_no_err_stub 16
-isr_err_stub    17
-isr_no_err_stub 18
-isr_no_err_stub 19
-isr_no_err_stub 20
-isr_no_err_stub 21
-isr_no_err_stub 22
-isr_no_err_stub 23
-isr_no_err_stub 24
-isr_no_err_stub 25
-isr_no_err_stub 26
-isr_no_err_stub 27
-isr_no_err_stub 28
-isr_no_err_stub 29
-isr_err_stub    30
-isr_no_err_stub 31
-
-global isr_stub_table
-isr_stub_table:
-%assign i 0 
-%rep    32 
-    dd isr_stub_%+i ; use DQ instead if targeting 64-bit
-%assign i i+1 
-%endrep
-

src/kernel/print.c

@@ -1,5 +1,5 @@
 #include "print.h"
-#include "./platform/drivers/ports.h"
+#include "./platform/ports.h"
 
 int row = 0;
 int col = 0;
@@ -87,10 +87,10 @@ void print_set_color(char foreground, char background) {
 
 void set_cursor_pos(int col, int row) {
    int offset = col + NUM_COLS * row;
-   port_byte_out(REG_SCREEN_CTRL, 14);
-   port_byte_out(REG_SCREEN_DATA, (unsigned char)(offset >> 8));
-   port_byte_out(REG_SCREEN_CTRL, 15);
-   port_byte_out(REG_SCREEN_DATA, (unsigned char)(offset & 0xff)); 
+   outb(REG_SCREEN_CTRL, 14);
+   outb(REG_SCREEN_DATA, (unsigned char)(offset >> 8));
+   outb(REG_SCREEN_CTRL, 15);
+   outb(REG_SCREEN_DATA, (unsigned char)(offset & 0xff)); 
 }
 
 void kernel_msg_ok(char* msg) {

src/linker.ld

@@ -1,32 +1,23 @@
-ENTRY(_start)
+
+ENTRY(entry_x86)
 
 SECTIONS
 {
 	. = 1M;
 
-    /* MB header */
-    .text BLOCK(4K) : ALIGN(4K)
+	.boot :
+	{
+		KEEP(*(.mb2_header))
+	}
+
+	.text :
 	{
-		*(.multiboot)
 		*(.text)
 	}
 
-    /* Read-only data. */
-	.rodata BLOCK(4K) : ALIGN(4K)
+	.idt BLOCK(0x1000) : ALIGN(0x1000)
 	{
-		*(.rodata)
-	}
- 
-	/* Read-write data (initialized) */
-	.data BLOCK(4K) : ALIGN(4K)
-	{
-		*(.data)
-	}
- 
-	/* Read-write data (uninitialized) and stack */
-	.bss BLOCK(4K) : ALIGN(4K)
-	{
-		*(COMMON)
-		*(.bss)
+		_idt = .;
+		. = . + 0x1000;
 	}
 }