rtc time

Makefile

@@ -9,7 +9,7 @@ GRUB_MKRESCUE = grub-mkrescue
 KERNEL = deados.bin
 ISO = deados.iso
 
-SOURCES_C = kernel.c tty.c idt.c timer.c io.c vga.c gdt.c sys.c irq.c isr.c keyboard.c shell.c string.c user_space.c syscall.c
+SOURCES_C = kernel.c tty.c idt.c timer.c io.c vga.c gdt.c sys.c irq.c isr.c keyboard.c shell.c string.c user_space.c syscall.c rtc.c
 SOURCES_ASM = boot.s idt_load.s gdt_flush.s tss_flush.s irq_flush.s isr_flush.s
 OBJECTS = $(SOURCES_ASM:.s=.o) $(SOURCES_C:.c=.o)
 

gdt.c

@@ -35,7 +35,7 @@ static void tss_install(uint8_t num, uint16_t kernel_ss, uint16_t kernel_esp)
     memset(&tss, 0, sizeof(Tss_entry));
 
     tss.ss0 = kernel_ss;
-    tss.esp0 = kernel_esp;
+    tss.esp0 = kernel_esp + 0x1000; // SHIT
 
     tss.cs = 0x1B;
     tss.ss = 0x23;
@@ -48,10 +48,10 @@ static void tss_install(uint8_t num, uint16_t kernel_ss, uint16_t kernel_esp)
 void gdt_install()
 {
     gdt_set_gate(0, 0x0, 0x0, 0x0, 0x0);          // Null segment
-    gdt_set_gate(1, 0x0, 0xFFFFFFFF, 0x9A, 0xCF); // Kernel code segment
-    gdt_set_gate(2, 0x0, 0xFFFFFFFF, 0x92, 0xCF); // Data segment
-    gdt_set_gate(3, 0x0, 0xFFFFFFFF, 0xFA, 0xCF); // User code segment
-    gdt_set_gate(4, 0x0, 0xFFFFFFFF, 0xF2, 0xCF); // User data segment
+    gdt_set_gate(1, 0x0, 0xFFFFFFFF, 0x9A, 0xCF); // 0x08 Kernel code segment
+    gdt_set_gate(2, 0x0, 0xFFFFFFFF, 0x92, 0xCF); // 0x10 Kernel Data segment
+    gdt_set_gate(3, 0x0, 0xFFFFFFFF, 0xFA, 0xCF); // 0x18 User code segment
+    gdt_set_gate(4, 0x0, 0xFFFFFFFF, 0xF2, 0xCF); // 0x20 User data segment
 
     tss_install(5, 0x10, stack_top);
 

io.c

@@ -12,9 +12,23 @@ uint8_t inb(uint16_t port)
     return ret;
 }
 
-void wait(void)
+void io_wait(void)
 {
     asm volatile("jmp 1f\n\t"
                  "1:jmp 2f\n\t"
                  "2:");
 }
+
+void outb_wait(uint16_t port, uint8_t val)
+{
+    outb(port, val);
+    io_wait();
+}
+
+uint8_t inb_wait(uint16_t port)
+{
+    uint8_t ret;
+    ret = inb(port);
+    io_wait();
+    return ret;
+}

io.h

@@ -7,4 +7,7 @@ void outb(uint16_t port, uint8_t val);
 uint8_t inb(uint16_t port);
 void io_wait(void);
 
+void outb_wait(uint16_t port, uint8_t val);
+uint8_t inb_wait(uint16_t port);
+
 #endif

isr.c

@@ -55,7 +55,9 @@ void isr_call_handler(Stack *registers)
     void (*handler)(Stack *registers);
     handler = isr_routines[registers->id];
     if (handler)
+    {
         handler(registers);
+    }
 }
 
 void isr_install(void)

kernel.c

@@ -12,9 +12,11 @@
 #include "shell.h"
 #include "user_space.h"
 #include "syscall.h"
+#include "rtc.h"
 
 void kernel_main(void)
 {
+    terminal_initialize();
     gdt_install();
 
     idt_install();
@@ -24,17 +26,18 @@ void kernel_main(void)
     timer_install();
     keyboard_install();
 
+    rtc_init();
+
     syscall_init();
     enter_user_space();
 }
 
 void main(void)
 {
-    terminal_initialize();
     for (int i = 1; i < 4; i++)
     {
         terminal_printf("&cTest &7%d\n", i);
-        delay(500);
+        delay(200);
     }
     terminal_clear();
 

rtc.c

@@ -0,0 +1,79 @@
+#include <stdint.h>
+#include "io.h"
+#include "interrupts.h"
+#include "rtc.h"
+
+uint8_t read_cmos(uint16_t reg)
+{
+    outb_wait(CMOS_ADDRESS, reg);
+    return inb_wait(CMOS_DATA);
+}
+
+uint8_t get_update_in_progress_flag()
+{
+    outb_wait(CMOS_ADDRESS, 0x0A);
+    return inb_wait(CMOS_DATA) & 0x80;
+}
+
+void rtc_handler()
+{
+    outb_wait(CMOS_ADDRESS, 0x0C);
+    inb_wait(CMOS_DATA);
+}
+
+uint8_t bcd_to_bin(uint8_t val)
+{
+    return ((val / 16) * 10) + (val & 0x0F);
+}
+
+struct Rtc_time get_rtc_time()
+{
+    struct Rtc_time time;
+
+    while (get_update_in_progress_flag())
+        ;
+
+    time.sec = read_cmos(REG_SECONDS);
+
+    time.min = read_cmos(REG_MINUTES);
+    time.hour = read_cmos(REG_HOURS);
+
+    time.mday = read_cmos(REG_DAY);
+    time.mon = read_cmos(REG_MONTH);
+    time.year = read_cmos(REG_YEAR);
+
+    uint8_t registerB = read_cmos(0x0B);
+
+    if (!(registerB & 0x04))
+    {
+        time.sec = bcd_to_bin(time.sec);
+        time.min = bcd_to_bin(time.min);
+        time.hour = bcd_to_bin(time.hour);
+        time.mday = bcd_to_bin(time.mday);
+        time.mon = bcd_to_bin(time.mon);
+        time.year = bcd_to_bin(time.year);
+    }
+
+    if (time.year < 70)
+    {
+        time.year += 100;
+    }
+    else if (time.year >= 100)
+    {
+        time.year -= 100;
+    }
+
+    time.year += 1900;
+
+    return time;
+}
+
+void rtc_init()
+{
+    outb_wait(CMOS_ADDRESS, 0x8A);
+    uint8_t prev = inb_wait(CMOS_DATA);
+    outb_wait(CMOS_ADDRESS, 0x8A);
+    outb_wait(CMOS_DATA, (prev & 0xF0) | 0x0F);
+
+    irq_install_handler(8, rtc_handler);
+}

rtc.h

@@ -0,0 +1,29 @@
+#ifndef RTC_H
+#define RTC_H
+
+#include <stdint.h>
+
+#define CMOS_ADDRESS 0x70
+#define CMOS_DATA 0x71
+
+#define REG_SECONDS 0x00
+#define REG_MINUTES 0x02
+#define REG_HOURS 0x04
+#define REG_DAY 0x07
+#define REG_MONTH 0x08
+#define REG_YEAR 0x09
+
+struct Rtc_time
+{
+    uint8_t sec;
+    uint8_t min;
+    uint8_t hour;
+    uint8_t mday;
+    uint8_t mon;
+    uint16_t year;
+};
+
+void rtc_init();
+struct Rtc_time get_rtc_time();
+
+#endif

shell.c

@@ -3,6 +3,7 @@
 #include "shell.h"
 #include "tty.h"
 #include "string.h"
+#include "rtc.h"
 
 void shell_init(void)
 {
@@ -53,6 +54,7 @@ void shell_help_command(void)
     terminal_printf("exit - Exit the shell.\n");
     terminal_printf("echo - Print out the message. &eWITH colors!&7\n");
     terminal_printf("clear - Clear the terminal.\n");
+    terminal_printf("time - Print out the current time. (UTC)\n");
 }
 
 void shell_exit_command(void)
@@ -63,6 +65,14 @@ void shell_exit_command(void)
         ;
 }
 
+void shell_time_command(void)
+{
+    struct Rtc_time current_time = get_rtc_time();
+    terminal_printf("Current time: %02d:%02d:%02d %02d.%02d.%d\n",
+                    current_time.hour, current_time.min, current_time.sec,
+                    current_time.mday, current_time.mon, current_time.year);
+}
+
 void shell_echo_command(char *input)
 {
     char *message = input;
@@ -102,6 +112,10 @@ void shell_parse_input(char *input)
     {
         terminal_clear();
     }
+    else if (strcmp(command, "time") == 0)
+    {
+        shell_time_command();
+    }
     else
     {
         terminal_printf("Unknown command: '");

string.c

@@ -21,6 +21,19 @@ void *memset(void *ptr, int value, size_t size)
     return ptr;
 }
 
+void memcpy(void *vd, const void *vs, unsigned length)
+{
+    char *d = vd;
+    const char *s = vs;
+    while (length)
+    {
+        *d = *s;
+        d++;
+        s++;
+        length--;
+    }
+}
+
 int strcmp(const char *str1, const char *str2)
 {
     while (*str1 && (*str1 == *str2))

string.h

@@ -10,5 +10,6 @@ size_t strlen(const char *str);
 void itoa(int value, char *str, int base);
 
 void *memset(void *ptr, int value, size_t size);
+void memcpy(void *vd, const void *vs, unsigned length);
 
 #endif

syscall.c

@@ -6,11 +6,13 @@
 #include "syscall.h"
 #include "tty.h"
 #include "timer.h"
+#include "rtc.h"
 
-#define NB_SYSCALL 2
+#define NB_SYSCALL 3
 
 void *syscalls[NB_SYSCALL] = {
     keyboard_getchar,
+    get_rtc_time,
 
     sys_halt};
 

tty.c

@@ -129,6 +129,21 @@ void terminal_print(const char *data)
     terminal_write(data, strlen(data));
 }
 
+static void print_number(int value, int base, int padding)
+{
+    char buffer[32];
+    itoa(value, buffer, base);
+    int len = strlen(buffer);
+
+    while (padding > len)
+    {
+        terminal_putchar('0');
+        padding--;
+    }
+
+    terminal_print(buffer);
+}
+
 void terminal_printf(const char *format, ...)
 {
     va_list args;
@@ -137,24 +152,29 @@ void terminal_printf(const char *format, ...)
     const char *p = format;
     while (*p)
     {
-        if (*p == '%' && (*(p + 1) == 's' || *(p + 1) == 'd' || *(p + 1) == 'x'))
+        if (*p == '%' && (*(p + 1) == 's' || *(p + 1) == 'd' || *(p + 1) == 'x' || *(p + 1) == '0'))
         {
             p++;
+            int padding = 0;
+
+            if (*p == '0')
+            {
+                p++;
+                padding = *p - '0';
+                p++;
+            }
+
             if (*p == 's')
             {
                 terminal_print(va_arg(args, const char *));
             }
             else if (*p == 'd')
             {
-                char buffer[12];
-                itoa(va_arg(args, int), buffer, 10);
-                terminal_print(buffer);
+                print_number(va_arg(args, int), 10, padding);
             }
             else if (*p == 'x')
             {
-                char buffer[12];
-                itoa(va_arg(args, unsigned int), buffer, 16);
-                terminal_print(buffer);
+                print_number(va_arg(args, unsigned int), 16, padding);
             }
         }
         else if (*p == '&' && ((*(p + 1) >= '0' && *(p + 1) <= '9') || (*(p + 1) >= 'a' && *(p + 1) <= 'f')))