Interrupts work now, fixed up GDT and IDT

f98f0cda · malcolm · b7c23627 · f98f0cda · f98f0cda · f98f0cda
Commit f98f0cda authored Oct 01, 2015 by malcolm
Showing with 73 additions and 13 deletions
src/gdt.c
src/idt.c
src/kern.c
src/makefile
src/string.c
src/string.h
--- a/src/gdt.c
+++ b/src/gdt.c
 #include "gdt.h"
 #include "string.h"
+#include "serial.h"
+#include "term.h"
 uint16_t gdt_limit;
 uint32_t gdt_base;
-static gdt_desc _gdt [MAX_GDT_DESC];
+gdt_desc _gdt [MAX_GDT_DESC];
-static void gdt_install(){
+#define set_cs( cs ) asm volatile ( "ljmp %0, $1337f \n\t 1337: \n\t" :: "i"(cs) )
+void gdt_install(){
  struct{
    uint16_t limit;
    uint32_t base;
@@ -14,6 +17,20 @@ static void gdt_install(){
  gdtr.limit = gdt_limit;
  gdtr.base = gdt_base;
  asm volatile ("lgdt (%0)": :"r"(&gdtr));
+  //serial_writestring("gdt installed, now setting cs\n");
+  set_cs(8);
+  //serial_writestring("cs set, setting ds\n");
+  //asm volatile ("ljmp $0x8,$1f;		
+  //               1:		
+  asm volatile("               mov $0x10, %ax;\
+                 mov %ax, %ds;\
+                 mov %ax, %es;\
+                 mov %ax, %fs;\
+                 mov %ax, %gs;\
+                 mov %ax, %ss;");
+  //serial_writestring("ds set, we done here. moving on to idt\n");
+  //terminal_writestring("");
+  strlen("");
 }
 void gdt_set_desc(uint32_t i, uint64_t base, uint64_t limit, uint8_t access, uint8_t gran){
  if (i > MAX_GDT_DESC)
@@ -30,7 +47,6 @@ void gdt_set_desc(uint32_t i, uint64_t base, uint64_t limit, uint8_t access, uin
  _gdt[i].gran |= gran & 0xf0;
 }
 gdt_desc* gdt_get_desc (int i) {
  if (i > MAX_GDT_DESC)
    return 0;
  return &_gdt[i];
@@ -44,6 +60,7 @@ int gdt_init() {
  gdt_set_desc(1,0,0xffffffff, GDT_RW|GDT_EXE|GDT_CDT|GDT_MEM, GDT_GR_PG|GDT_GR_32|GDT_GR_HI);
  //data
  gdt_set_desc(2,0,0xffffffff, GDT_RW|GDT_CDT|GDT_MEM, GDT_GR_PG|GDT_GR_32|GDT_GR_HI);
+  //serial_writestring("gdt filled, now installing\n");
  gdt_install();
  return 0;
 }
--- a/src/idt.c
+++ b/src/idt.c
@@ -5,22 +5,33 @@
 uint16_t idt_limit;
 uint32_t idt_base;
-static idt_desc _idt [MAX_IDT_INT];
+idt_desc _idt [MAX_IDT_INT];
-static void idt_install(){
+void idt_install() {
  struct{
    uint16_t limit;
    uint32_t base;
  } __attribute__((packed)) idtr;
+  //char s[1];
+  //itoa(sizeof(idtr),s);
+  //serial_writestring(s);
  idtr.limit = idt_limit;
  idtr.base = idt_base;
+  char f[20];
+  itoa(idtr.limit,f);
+  //serial_writestring(f);
+  //serial_writestring("\n");
+  itoa(idtr.base,f);
+  //serial_writestring(f);
+  //serial_writestring("\n");
  asm volatile ("lidt (%0)": :"r"(&idtr));
 }
 static void default_handler () {
  //DEBUG OUTPUT MAYBE?
  serial_writestring("int caught\n");
-  for(;;);
+  //for(;;);
+  return;
 }
 idt_desc* get_ir (uint32_t i) {
@@ -28,6 +39,7 @@ idt_desc* get_ir (uint32_t i) {
    return 0;
  return &_idt[i];
 }
 int install_ir (uint32_t i, uint16_t flags, uint16_t code_sel, IRQ_HANDLER irq) {
  if (i>MAX_IDT_INT)
    return 0;
@@ -37,16 +49,20 @@ int install_ir (uint32_t i, uint16_t flags, uint16_t code_sel, IRQ_HANDLER irq) 
  _idt[i].low_base  = (uint16_t)(uiBase & 0xffff);
  _idt[i].high_base = (uint16_t)((uiBase >> 16) & 0xffff);
  _idt[i].reserved  = 0;
-  _idt[i].flags	  = (uint8_t)(flags);
+  _idt[i].flags	    = (uint8_t)(flags);
  _idt[i].code_sel  = code_sel;
  return 0;
 }
 int idt_init (uint16_t code_sel) {
  idt_limit = sizeof (idt_desc) * MAX_IDT_INT -1;
  idt_base  = (uint32_t)&_idt[0];
  memset ((void*)&_idt[0], 0, sizeof (idt_desc) * MAX_IDT_INT-1);
  for (int i=0; i<MAX_IDT_INT; i++)
    install_ir (i, IDT_PR|IDT_32,code_sel,(IRQ_HANDLER)default_handler);
-  idt_install ();
+  idt_install();
+  char f[20];
+  itoa((uintptr_t)&_idt,f);
+  //serial_writestring(f);
  return 0;
 }
--- a/src/kern.c
+++ b/src/kern.c
@@ -2,6 +2,7 @@
 #include <stddef.h>
 #include <stdint.h>
+#include "string.h"
 #include "serial.h"
 #include "term.h"
 #include "mem.h"
@@ -13,18 +14,23 @@ extern "C" /* Use C linkage for kernel_main. */
 #endif
 void kernel_main() {
 	/* Initialize terminal and serial interfaces */
-	terminal_initialize();
+  terminal_initialize();
    serial_init();
+    char b[2];
+    int a = strlen("");
+    itoa(a,b);
+    terminal_writestring(b);
    gdt_init();
-    idt_init(0x0);
+    idt_init(0x8);
 	/* Since there is no support for newlines in terminal_putchar
         * yet, '\n' will produce some VGA specific character instead.
         * This is normal.
         */
-    serial_writestring("First Serial Test!\n");
+    serial_writestring("IDT initialized\n");
    terminal_writestring("Hello, kernel World!\n");
-    serial_writestring("Second Serial Test\n");
+    //serial_writestring("Second Serial Test\n");
    // Enable paging of memory. For now there is only one virtual
    // memory space defined by page_dir
@@ -35,4 +41,7 @@ void kernel_main() {
    enablePaging();
    serial_writestring("Finished Initilizing memory\n");
+    asm ("int $0x80");
+    asm ("int $0x90");
+    asm ("hlt");
 }
--- a/src/makefile
+++ b/src/makefile
-C=/home/adam/college/kernel/cross/bin/i686-elf-gcc
+C=i686-elf-gcc
 all:
 	/usr/bin/nasm -felf32 head.asm -o boot.o

--- a/src/string.c
+++ b/src/string.c
@@ -6,3 +6,19 @@ void *memset(void *s, int c, size_t n){
    *p++=(unsigned char) c;
  return s;
 }
+void itoa(int n, char s[])
+ {
+     int i, sign;
+     if ((sign = n) < 0)  /* record sign */
+         n = -n;          /* make n positive */
+     i = 0;
+     do {       /* generate digits in reverse order */
+         s[i++] = n % 10 + '0';   /* get next digit */
+     } while ((n /= 10) > 0);     /* delete it */
+     if (sign < 0)
+         s[i++] = '-';
+     s[i] = '\0';
+     //reverse(s);
+ }
--- a/src/string.h
+++ b/src/string.h
@@ -3,4 +3,6 @@
 #include<stddef.h>
 void* memset(void *s, int c, size_t n);
+void itoa(int n, char s[]);
 #endif