M link.txt → link.txt

@@ -39,24 +39,20 @@
   } >KERNEL_VMA
 }
 
-__SS_LMA = LOADADDR(BOOT);
-__SS_VMA = ADDR(BOOT);
-__SS_SIZE = SIZEOF(BOOT);
+__BOOT_LMA = LOADADDR(BOOT);
+__BOOT_VMA = ADDR(BOOT);
+__BOOT_SIZE = SIZEOF(BOOT);
 
 __KERNEL_LMA = LOADADDR(KERNEL);
 __KERNEL_VMA = ADDR(KERNEL);
 __KERNEL_SIZE = SIZEOF(KERNEL);
 
-
-
-__APP_LMA = LOADADDR(APPLICATION);
-__APP_VMA = ADDR(APPLICATION);
-__APP_SIZE = SIZEOF(APPLICATION);
-
 __ELF_LMA = LOADADDR(ELF);
 __ELF_VMA = ADDR(ELF);
 __ELF_SIZE = SIZEOF(ELF);
 
 __KERNEL_STACK_ADDR = 0xC0400000;
 
-ASSERT(__SS_SIZE + __KERNEL_SIZE + __APP_SIZE + __ELF_SIZE <= 0x48 * 0x200, "bootloader payload too big!");
+ASSERT(__BOOT_SIZE <= 0x1000, "bootloader too big!");
+ASSERT(__KERNEL_SIZE <= 0x5000, "bootloader too big!");
+ASSERT(__ELF_SIZE <= 0x3000, "bootloader too big!");

M src/boot/linker.h → src/boot/linker.h

@@ -6,10 +6,6 @@ #define LINKER_H
 
 #include <stdint.h>
 
-extern uint8_t __SS_VMA;
-extern uint8_t __SS_LMA;
-extern uint8_t __SS_SIZE;
-
 extern uint8_t __KERNEL_VMA;
 extern uint8_t __KERNEL_LMA;
 extern uint8_t __KERNEL_SIZE;
@@ -17,10 +13,6 @@
 extern uint8_t __APP_VMA;
 extern uint8_t __APP_LMA;
 extern uint8_t __APP_SIZE;
-
-#define SS_VMA (&__SS_VMA)
-#define SS_LMA (&__SS_LMA)
-#define SS_SIZE (uint32_t)(&__SS_SIZE)
 
 #define KERNEL_VMA (&__KERNEL_VMA)
 #define KERNEL_LMA (&__KERNEL_LMA)

D src/boot/main.c

@@ -1,47 +0,0 @@
-#include "linker.h"
-#include "paging.h"
-
-/*
-#define VGA_TEXTMODE_COLUMNS 80
-#define VGA_TEXTMODE_LINES 25
-#define VGA_TEXTMODE_CELLS (VGA_TEXTMODE_COLUMNS * VGA_TEXTMODE_LINES)
-
-#define VGA_TEXT_COLOR 0x02
-
-uint8_t const *display_start = (uint8_t*)0xB8000;
-uint8_t *display = (uint8_t*)0xB8000;
-
-void simple_clear(void) {
-    display = (uint8_t*)display_start;
-
-    for (int i = 0; i < VGA_TEXTMODE_CELLS; i++) {
-        display[2 * i] = 0x00;
-        display[2 * i + 1] = 0x00;
-    }
-}
-
-void simple_print(const char *src) {
-    while (*src) {
-        *display++ = *src++;
-        *display++ = VGA_TEXT_COLOR;
-    }
-}
-
-void simple_println(const char *src) {
-    simple_print(src);
-
-    while ((display - display_start) % (2 * VGA_TEXTMODE_COLUMNS)) {
-        display++;
-        display++;
-    }
-}
-*/
-
-void copy_kernel(void) {
-    uint8_t *kernel_dest = (uint8_t*)0x00100000;
-    uint8_t *kernel_src = (uint8_t*)0x00010000;
-    
-    for (uint32_t i = 0; i < 0x8000; i++) {
-        kernel_dest[i] = kernel_src[i];
-    }
-}

M src/boot/paging.c → src/boot/paging.c

@@ -23,7 +23,7 @@ // map 4M of kernel to 0xC0000000
     (*pdir)[PAGE_DIR_INDEX(KERNEL_VMA)].entry = MAKE_PAGE_ENTRY(kernel, 0b000000000011);
 
     for (uint32_t i = 0; i < 1 << 10; i++) {
-        (*kernel)[i].entry = MAKE_PAGE_ENTRY(0x100000 + PAGE_SIZE * i, 0b000000000011);
+        (*kernel)[i].entry = MAKE_PAGE_ENTRY(0x10000 + PAGE_SIZE * i, 0b000000000011);
     }
 
     // identity map first 4M of memory

M src/boot/stage1.s → src/boot/entry.s

@@ -362,9 +362,25 @@ mov %eax, %es
   mov %eax, %fs
   mov %eax, %gs
   mov %eax, %ss
+  
+  # create a page directory for the kernel that maps it to 0xC0000000
+  # and identity maps the first 1M of memory
+  call create_kernel_environment
+  
+  # load kernel page directory
+  movl %eax, %cr3
 
-  # jump to second stage code
-  ljmp $0x08, $__SS_START
+  # set paging enable and protection bit
+  movl %cr0, %eax
+  or $0x80000010, %eax
+  movl %eax, %cr0
+
+  # jump to kernel code
+  ljmp $8, $__KERNEL_START
+
+  # loop until the heat death of the universe
+loop:
+  jmp loop
  
 
 .section .data 

D src/boot/stage2.s

@@ -1,24 +0,0 @@
-.section .text
-.global __SS_START
-__SS_START:
-  # copy the kernel code to 0x00100000
-  call copy_kernel
-
-  # create a page directory for the kernel that maps it to 0xC0000000
-  # and identity maps the first 1M of memory
-  call create_kernel_environment
-  
-  # load kernel page directory
-  movl %eax, %cr3
-
-  # set paging enable and protection bit
-  movl %cr0, %eax
-  or $0x80000010, %eax
-  movl %eax, %cr0
-
-  # jump to kernel code
-  ljmp $8, $__KERNEL_START
-
-  # loop until the heat death of the universe
-loop:
-  jmp loop