PIT

build.ninja

@@ -23,14 +23,15 @@ build ./build/i386/pic.o: gcc ./src/arch/i386/kernel/drivers/pic.c
 build ./build/i386/cmos.o: gcc ./src/arch/i386/kernel/drivers/cmos.c
 build ./build/i386/keyboard.o: gcc ./src/arch/i386/kernel/drivers/keyboard.c
 build ./build/i386/fpu.o: gcc ./src/arch/i386/kernel/drivers/fpu.c
+build ./build/i386/pit.o: gcc ./src/arch/i386/kernel/drivers/pit.c
 build ./build/i386/console.o: gcc ./src/arch/i386/kernel/console.c
 build ./build/i386/kernel.o: gcc ./src/arch/i386/kernel/kernel.c
 
-build ./isodir/boot/piriquitOS-i386.bin: ld ./build/libc/string.o ./build/i386/boot.o ./build/i386/gdt.asm.o ./build/i386/gdt.c.o ./build/i386/idt.c.o ./build/i386/idt.asm.o ./build/i386/irq.o ./build/i386/exceptions.o ./build/i386/isr.o ./build/i386/io.o ./build/i386/vga.o ./build/i386/pic.o ./build/i386/cmos.o ./build/i386/keyboard.o ./build/i386/console.o ./build/i386/fpu.o ./build/i386/kernel.o
+build ./isodir/boot/piriquitOS-i386.bin: ld ./build/libc/string.o ./build/i386/boot.o ./build/i386/gdt.asm.o ./build/i386/gdt.c.o ./build/i386/idt.c.o ./build/i386/idt.asm.o ./build/i386/irq.o ./build/i386/exceptions.o ./build/i386/isr.o ./build/i386/io.o ./build/i386/vga.o ./build/i386/pic.o ./build/i386/cmos.o ./build/i386/keyboard.o ./build/i386/pit.o ./build/i386/console.o ./build/i386/fpu.o ./build/i386/kernel.o
 build ./build/piriquitOS-i386.iso: iso ./isodir
 
 #phony
 build libc: phony ./build/libc/string.o ./libs/libc.a
-build i386: phony ./build/libc/string.o ./build/i386/boot.o ./build/i386/gdt.asm.o ./build/i386/idt.asm.o ./build/i386/irq.o ./build/i386/exceptions.o ./build/i386/isr.o ./build/i386/io.o ./build/i386/vga.o ./build/i386/pic.o ./build/i386/cmos.o ./build/i386/keyboard.o ./build/i386/console.o ./build/i386/fpu.o ./build/i386/kernel.o ./isodir/boot/piriquitOS-i386.bin ./build/piriquitOS-i386.iso
+build i386: phony ./build/libc/string.o ./build/i386/boot.o ./build/i386/gdt.asm.o ./build/i386/idt.asm.o ./build/i386/irq.o ./build/i386/exceptions.o ./build/i386/isr.o ./build/i386/io.o ./build/i386/vga.o ./build/i386/pic.o ./build/i386/cmos.o ./build/i386/keyboard.o ./build/i386/console.o ./build/i386/fpu.o ./build/i386/pit.o ./build/i386/kernel.o ./isodir/boot/piriquitOS-i386.bin ./build/piriquitOS-i386.iso
 
 default help

rules.ninja

@@ -1,6 +1,6 @@
 NASMARGS = -f elf32
-LDARGS = -m elf_i386 -T ./src/arch/i386/linker.ld -nostdlib
-CCARGS = -m32 -std=gnu99 -ffreestanding -Wall -Wextra -c
+LDARGS = -m elf_i386 -T ./src/arch/i386/linker.ld -nostdlib -z noexecstack
+CCARGS = -m32 -std=gnu99 -ffreestanding -fcompare-debug -Wall -Wextra -c
 CCINCLUDES = -L./libs -lc -I ./src/arch/i386/kernel/include
 ARARGS = -rcs
 

src/arch/i386/kernel/drivers/cmos.c

@@ -1,4 +1,6 @@
 #include "../include/drivers/cmos.h"
+#include "../include/drivers/pic.h"
+#include "../include/isr.h"
 #include "../include/io.h"
 
 void rtc_handler(struct registers_t *r) {
@@ -8,6 +10,8 @@ void rtc_handler(struct registers_t *r) {
     u8 day = cmos_read(RTC_DAY);
     u8 month = cmos_read(RTC_MONTH);
     u8 year = cmos_read(RTC_YEAR);
+
+    pic_eoi(IRQ_CMOS);
 }
 
 void init_cmos(){

src/arch/i386/kernel/drivers/pic.c

@@ -1,34 +1,32 @@
 #include "../include/libc/include/types.h"
-#include "../include/isr.h"
-#include "../include/idt.h"
 #include "../include/io.h"
 #include "../include/drivers/pic.h"
 
 void init_pic() {
     printf("Initiating PIC...\n");
     u8 a1, a2;
 
-    a1 = inportb(PIC1_DATA);
-    a2 = inportb(PIC2_DATA);
+    a1 = inportb(PIC_MASTER_DATA);
+    a2 = inportb(PIC_SLAVE_DATA);
 
-    outportb(PIC1_COMMAND, ICW1);
-    outportb(PIC2_COMMAND, ICW1);
+    outportb(PIC_MASTER_COMMAND, PIC_ICW1);
+    outportb(PIC_SLAVE_COMMAND, PIC_ICW1);
 
-    outportb(PIC1_DATA, 0x20);
-    outportb(PIC2_DATA, 0x28);
+    outportb(PIC_MASTER_DATA, 0x20);
+    outportb(PIC_SLAVE_DATA, 0x28);
 
-    outportb(PIC1_DATA, 4);
-    outportb(PIC2_DATA, 2);
+    outportb(PIC_MASTER_DATA, 4);
+    outportb(PIC_SLAVE_DATA, 2);
 
-    outportb(PIC1_DATA, ICW4_8086);
-    outportb(PIC2_DATA, ICW4_8086);
+    outportb(PIC_MASTER_DATA, PIC_ICW4_8086);
+    outportb(PIC_SLAVE_DATA, PIC_ICW4_8086);
 
-    outportb(PIC1_DATA, a1);
-    outportb(PIC2_DATA, a2);
+    outportb(PIC_MASTER_DATA, a1);
+    outportb(PIC_SLAVE_DATA, a2);
 }
 
 void pic_eoi(u8 irq) {
     if(irq >= 0x28)
-        outportb(PIC2, PIC_EOI);
-    outportb(PIC1, PIC_EOI);
+        outportb(PIC_SLAVE_COMMAND, PIC_EOI);
+    outportb(PIC_MASTER_COMMAND, PIC_EOI);
 }

src/arch/i386/kernel/drivers/pit.c

@@ -0,0 +1,92 @@
+#include "../include/drivers/pit.h"
+#include "../include/console.h"
+#include "../include/io.h"
+#include "../include/isr.h"
+
+u64 ticks;
+const u32 freq = 100;
+
+void pit_handler(struct registers_t *r) { ticks += 1; }
+
+void init_pit() {
+  printf("Initiating PIT...\n");
+  isr_register_interrupt_handler(IRQ_BASE + IRQ_TIMER, pit_handler);
+  start_pit_timer();
+}
+
+void start_pit_timer() {
+  if (freq == 0) {
+    printf("Can't divide by zero!");
+    return;
+  }
+
+  u16 divisor = 1193180 / freq;
+
+  outportb(PIT_COMMAND_PORT, PIT_COMMAND_REGISTER);
+  outportb(PIT_CH0_DATA_PORT, (u8)(divisor & 0xFF)); // Send the low byte
+  outportb(PIT_CH0_DATA_PORT, (u8)((divisor >> 8) & 0xFF)); // Send the high byte
+}
+
+void stop_pit_timer() { outportb(PIT_COMMAND_PORT, 0x30); }
+
+u8 read_pit(u8 channel) {
+  u8 port;
+  switch (channel) {
+  case 0:
+    port = PIT_CH0_DATA_PORT;
+    break;
+  case 1:
+    port = PIT_CH1_DATA_PORT;
+    break;
+  case 2:
+    port = PIT_CH2_DATA_PORT;
+    break;
+  default:
+    // Handle invalid channel
+    break;
+  }
+
+  // Read from the specified channel
+  u8 value = inportb(port);
+  return value;
+}
+
+void write_pit(u8 channel, u8 value) {
+  u8 port;
+  switch (channel) {
+  case 0:
+    port = PIT_CH0_DATA_PORT;
+    break;
+  case 1:
+    port = PIT_CH1_DATA_PORT;
+    break;
+  case 2:
+    port = PIT_CH2_DATA_PORT;
+    break;
+  default:
+    // Handle invalid channel
+    break;
+  }
+
+  // Write to the specified channel
+  outportb(port, value);
+}
+
+void sleep(u32 milliseconds) {
+    // Calculate the number of PIT ticks needed for the delay
+    u32 ticks = milliseconds * 1000 / ticks;
+
+    // Save the current PIT channel 0 count
+    u8 initialCounter = inportb(PIT_CH0_DATA_PORT);
+
+    start_pit_timer();
+
+    while (ticks > 0) {
+        // Wait for PIT interrupt
+        ticks--;
+    }
+
+    // Restore the initial PIT channel 0 count
+    outportb(PIT_COMMAND_REGISTER, 0x36); // Set the operating mode to square wave generator
+    outportb(PIT_CH0_DATA_PORT, initialCounter); // Set the initial counter value
+}

src/arch/i386/kernel/include/drivers/cmos.h

@@ -7,13 +7,12 @@
 #define CMOS_ADDR_REG 0x70
 #define CMOS_DATA_REG 0x71
 
-//RTC register addresses
 #define RTC_SECONDS 0x00
 #define RTC_MINUTES 0x02
 #define RTC_HOURS   0x04
 #define RTC_DAY     0x07
 #define RTC_MONTH   0x08
-#define RTC_YEAR    0x09
+#define RTC_YEAR    0x09 //last two digits
 
 void init_cmos();
 u8 cmos_read(u8 reg);

src/arch/i386/kernel/include/drivers/pic.h

@@ -3,17 +3,15 @@
 
 #include "../libc/include/types.h"
 
-#define PIC1            0x20  //master PIC
-#define PIC2            0xA0  //slave PIC
-#define PIC1_COMMAND    PIC1
-#define PIC1_DATA       (PIC1+1)    //master data
-#define PIC2_COMMAND    PIC2
-#define PIC2_DATA       (PIC2+1)    //slave data
+#define PIC_MASTER_COMMAND    0X20
+#define PIC_MASTER_DATA       0X21
+#define PIC_SLAVE_COMMAND     0XA0
+#define PIC_SLAVE_DATA        0xA1
 
 #define PIC_EOI         0x20
 
-#define ICW1            0x11    /* interrupt control command word PIC for initialization */
-#define ICW4_8086       0x01    /* 8086/88 (MCS-80/85) mode */
+#define PIC_ICW1            0x11    /* interrupt control command word PIC for initialization */
+#define PIC_ICW4_8086       0x01    /* 8086/88 (MCS-80/85) mode */
 
 void init_pic();
 

src/arch/i386/kernel/include/drivers/pit.h

@@ -0,0 +1,19 @@
+#ifndef PIT_H
+#define PIT_H
+
+#define PIT_CH0_DATA_PORT 0x40
+#define PIT_CH1_DATA_PORT 0x41
+#define PIT_CH2_DATA_PORT 0x42
+#define PIT_COMMAND_PORT 0x43
+#define PIT_COMMAND_REGISTER 0x36
+
+#include "../libc/include/types.h"
+
+void init_pit();
+void start_pit_timer();
+void stop_pit_timer();
+void sleep(u32 milliseconds);
+u8 read_pit(u8 channel);
+void write_pit(u8 channel, u8 value);
+
+#endif

src/arch/i386/kernel/include/io.h

@@ -4,13 +4,11 @@
 #include "libc/include/types.h"
 
 u8 inportb(u16 port);
-u16 inports(u16 port);
+u16 inportw(u16 port);
 u32 inportl(u16 port);
 
-void outportb(u16 port, u8 val);
-void outports(u16 port, u16 data);
+void outportb(u16 port, u8 data);
+void outportw(u16 port, u16 data);
 void outportl(u16 port, u32 data);
 
-void insw(u16 port, void *buffer, u32 count);
-
 #endif

src/arch/i386/kernel/include/isr.h

@@ -73,21 +73,21 @@ extern void irq_14();
 extern void irq_15();
 
 #define IRQ_BASE            0x20
-#define IRQ_TIMER           0x20
-#define IRQ_KEYBOARD        0x21
-#define IRQ_CASCADE         0x22
-#define IRQ_SERIAL_PORT2    0x23
-#define IRQ_SERIAL_PORT1    0x24
-#define IRQ_AUDIO           0x25
-#define IRQ_DISKETTE_DRIVE  0x26
-#define IRQ_PARALLEL_PORT   0x27
-#define IRQ_CMOS            0x28
-#define IRQ_CGA             0x29
-#define IRQ_NIC1            0x2A
-#define IRQ_NIC2            0x2B
-#define IRQ_AUXILIARY       0x2C
-#define IRQ_FPU             0x2D
-#define IRQ_ATA1            0x2E
-#define IRQ_ATA2            0x2F
+#define IRQ_TIMER           0x00
+#define IRQ_KEYBOARD        0x01
+#define IRQ_CASCADE         0x02
+#define IRQ_SERIAL_PORT2    0x03
+#define IRQ_SERIAL_PORT1    0x04
+#define IRQ_AUDIO           0x05
+#define IRQ_DISKETTE_DRIVE  0x06
+#define IRQ_PARALLEL_PORT   0x07
+#define IRQ_CMOS            0x08
+#define IRQ_ACPI            0x09
+#define IRQ_NIC1            0x0A
+#define IRQ_NIC2            0x0B
+#define IRQ_AUXILIARY       0x0C
+#define IRQ_FPU             0x0D
+#define IRQ_ATA1            0x0E
+#define IRQ_ATA2            0x0F
 
 #endif

src/arch/i386/kernel/io.c

@@ -1,57 +1,33 @@
-#include "./include/libc/include/types.h"
-#include "./include/libc/include/defines.h"
 #include "include/io.h"
+#include "./include/libc/include/defines.h"
+#include "./include/libc/include/types.h"
 
-u8 inportb(u16 port)
-{
-    u8 ret;
-    asmv("inb %1, %0"
-         : "=a"(ret)
-         : "Nd"(port));
-    return ret;
-}
-
-void outportb(u16 port, u8 val)
-{
-    asmv("outb %1, %0" ::"dN"(port), "a"(val));
+u8 inportb(u16 port) {
+  u8 ret;
+  asmv("inb %1, %0" : "=a"(ret) : "dN"(port));
+  return ret;
 }
 
-u16 inports(u16 port)
-{
-    u16 rv;
-    asmv("inw %1, %0"
-         : "=a"(rv)
-         : "dN"(port));
-    return rv;
+void outportb(u16 port, u8 data) {
+  asmv("outb %1, %0" ::"dN"(port), "a"(data));
 }
 
-void outports(u16 port, u16 data)
-{
-    asmv("outw %1, %0"
-         :
-         : "dN"(port), "a"(data));
+u16 inportw(u16 port) {
+  u16 rv;
+  asmv("inw %1, %0" : "=a"(rv) : "dN"(port));
+  return rv;
 }
 
-u32 inportl(u16 port)
-{
-    u32 rv;
-    asmv("inl %%dx, %%eax"
-         : "=a"(rv)
-         : "dN"(port));
-    return rv;
+void outportw(u16 port, u16 data) {
+  asmv("outw %1, %0" : : "dN"(port), "a"(data));
 }
 
-void outportl(u16 port, u32 data)
-{
-    asmv("outl %%eax, %%dx"
-         :
-         : "dN"(port), "a"(data));
+u32 inportl(u16 port) {
+  u32 rv;
+  asmv("inl %%dx, %%eax" : "=a"(rv) : "dN"(port));
+  return rv;
 }
 
-void insw(u16 port, void *buffer, u32 count)
-{
-    asmv("cld; rep insw"
-         : "+D"(buffer), "+c"(count)
-         : "d"(port)
-         : "memory");
+void outportl(u16 port, u32 data) {
+  asmv("outl %%eax, %%dx" : : "dN"(port), "a"(data));
 }