Create pic.c

Implementation for pic.h

Makefile

@@ -8,13 +8,8 @@ OBJCOPY = i386-elf-objcopy
 BUILD_DIR = build
 CROSS_DIR = cross
 DISK_IMG = $(BUILD_DIR)/disk.img
-
-STAGE2_ADDR = 0x7e00
 STAGE2_SIZE = 2048
 
-# Place the memory map (e820) past stage2 bl in memory
-MEMMAP_BASE = $(shell echo $$(($(STAGE2_ADDR) + $(STAGE2_SIZE))))
-
 KERNEL_C_SRC = $(wildcard kernel/*.c)
 KERNEL_ASM_SRC = $(wildcard kernel/*.asm)
 KERNEL_OBJ = $(patsubst kernel/%.c, $(BUILD_DIR)/%.o, $(KERNEL_C_SRC))
@@ -34,7 +29,7 @@ stage1: $(BUILD_DIR)
 # NOTE: Stage2 final size should be checked against `$(STAGE2_SIZE)` by the build system to avoid an overflow.
 # Alternatively, convey the final stage2 size through other means to stage1.
 stage2: $(BUILD_DIR)
-	$(AS) $(ASFLAGS) -DMEMMAP_BASE=$(MEMMAP_BASE) -o $(BUILD_DIR)/stage2.o bootloader/stage2.asm
+	$(AS) $(ASFLAGS) -o $(BUILD_DIR)/stage2.o bootloader/stage2.asm
 	$(CC) -std=c11 -ffreestanding -nostdlib -nostdinc -fno-stack-protector -m32 -Iklibc/include -g -c -o $(BUILD_DIR)/stage2_load.o bootloader/stage2_load.c
 	$(LD) -Tbootloader/stage2.ld -melf_i386 -o $(BUILD_DIR)/$@.elf $(BUILD_DIR)/stage2.o $(BUILD_DIR)/stage2_load.o
 	$(OBJCOPY) -O binary $(BUILD_DIR)/$@.elf $(BUILD_DIR)/$@.bin
@@ -44,7 +39,7 @@ $(BUILD_DIR)/asm_%.o: kernel/%.asm
 	$(AS) $(ASFLAGS) -o $@ $<
 
 $(BUILD_DIR)/%.o: kernel/%.c
-	$(CC) -DMEMMAP_BASE=$(MEMMAP_BASE) -std=c11 -ffreestanding -nostdlib -nostdinc -fno-stack-protector -m32 -Iklibc/include -g -c -o $@ $<
+	$(CC) -std=c11 -ffreestanding -nostdlib -nostdinc -fno-stack-protector -m32 -Iklibc/include -g -c -o $@ $<
 
 $(BUILD_DIR)/klibc/%.o: klibc/src/%.c
 	$(CC) -std=c11 -ffreestanding -nostdlib -nostdinc -fno-stack-protector -m32 -Iklibc/include -g -c -o $@ $<

bootloader/README.md

@@ -11,16 +11,16 @@ Bootloader documentation for ClassicOS
 
 ## Stage 1 (`stage1.asm`)
 
+Responsible for loading the second stage using BIOS routines, and switching to protected mode.
+
 - Queries CHS parameters from BIOS
 - Loads the second stage bootloader (2048 B) to `0x7c00`
+- Sets up a GDT with descriptor entries for code and data both covering the whole 32-bit address space
 - Enables A20
-- Jumps to stage2
+- Set CR0.PE (enable protected mode) and jump to stage 2
 
 ## Stage 2 (`stage2.asm, stage2_load.c`)
 
-- Read and store E820 memory map from BIOS
-- Sets up a GDT with descriptor entries for code and data both covering the whole 32-bit address space
-- Set CR0.PE (enable protected mode)
 - Set up segment registers
 - Load the kernel ELF header
 - Parse the program headers, and load all `PT_LOAD` segments from disk

bootloader/stage1.asm

@@ -40,8 +40,11 @@ _start:
     call enable_a20
     jc a20_error                ; Jump if A20 enable fails
 
-    ; Jump to s2
-    jmp 0x7e00
+    ; Setup Global Descriptor Table
+    call setup_gdt
+
+    ; Switch to protected mode and jump to second stage at 0x08:0x7E00
+    call switch_to_pm
 
 disk_error:
     mov si, disk_error_msg
@@ -238,6 +241,30 @@ check_a20:
     clc                      ; Clear carry flag to indicate success
     ret
 
+; ----------------------------------------------------------------
+gdt_start:
+    dq 0x0000000000000000         ; Null descriptor
+    dq 0x00CF9A000000FFFF         ; 32-bit code segment (selector 0x08)
+    dq 0x00CF92000000FFFF         ; 32-bit data segment (selector 0x10)
+    dq 0x00009A000000FFFF         ; 16-bit code segment for real mode (selector 0x18)
+
+gdt_descriptor:
+    dw gdt_end - gdt_start - 1
+    dd gdt_start
+gdt_end:
+
+setup_gdt:
+    lgdt [gdt_descriptor]
+    ret
+
+; ----------------------------------------------------------------
+switch_to_pm:
+    cli
+    mov eax, cr0
+    or eax, 1
+    mov cr0, eax
+    jmp 0x08:0x7E00             ; jump to S2
+
 ; ----------------------------------------------------------------
 print_string_16:
 .loop:

bootloader/stage2.asm

@@ -1,80 +1,10 @@
+[BITS 32]
 global _start
+global ata_lba_read
+
 extern load_kernel
 
-%define e820_magic 0x534d4150 ; "SMAP"
-%define e820_entry_size 24
-%define e820_max_entries 128
-
-; ----------------------------------------------------------------
-; Real mode
-; ----------------------------------------------------------------
-[BITS 16]
 _start:
-    call read_e820
-    call setup_gdt
-    call switch_to_pm
-
-read_e820:
-    xor ebx, ebx
-    mov es, bx
-    mov di, MEMMAP_BASE+4       ; ES=0 DI=MEMMAP_BASE+4
-    xor bp, bp                  ; Keeping count in bp
-
-.e820_loop:
-    mov eax, 0xe820
-    mov ecx, e820_entry_size
-    mov edx, e820_magic
-    int 0x15
-    jc .done                    ; Error?
-
-    cmp eax, e820_magic         ; Verify "SMAP"
-    jne .done
-
-    test ecx, ecx               ; Skip 0-sized entries
-    jz .skip
-
-    add di, e820_entry_size     ; Advance write addr
-    inc bp                      ; Increment count
-
-    cmp bp, e820_max_entries    ; Stop if we're at capacity
-    jae .done
-.skip:
-    test ebx, ebx
-    jne .e820_loop
-.done:
-    mov [MEMMAP_BASE], bp       ; Store count
-    ret
-
-setup_gdt:
-    lgdt [gdt_descriptor]
-    ret
-
-switch_to_pm:
-    cli
-    mov eax, cr0
-    or eax, 1
-    mov cr0, eax
-    jmp 0x08:pm_entry
-
-e820_count:
-    dw 0
-
-gdt_start:
-    dq 0x0000000000000000         ; Null descriptor
-    dq 0x00CF9A000000FFFF         ; 32-bit code segment (selector 0x08)
-    dq 0x00CF92000000FFFF         ; 32-bit data segment (selector 0x10)
-    dq 0x00009A000000FFFF         ; 16-bit code segment for real mode (selector 0x18)
-gdt_descriptor:
-    dw gdt_end - gdt_start - 1
-    dd gdt_start
-gdt_end:
-
-; ----------------------------------------------------------------
-; Protected mode
-; ----------------------------------------------------------------
-[BITS 32]
-
-pm_entry:
     ; Set up segments
     ; Data segments
     mov ax, 0x10
@@ -88,8 +18,9 @@ pm_entry:
     mov ax, 0x08
     mov cs, ax
 
-    ; Stack
+    ; Stack (must be identity-mapped)
     mov esp, 0x90000
 
     call load_kernel
+
     jmp eax

kernel/fat16.c

@@ -1,107 +0,0 @@
-#include "fat16.h"
-#include "ata.h"   // Use ata_read_sector and ata_write_sector
-#include "print.h" // For debugging
-#include <string.h> // For string manipulation
-
-// Global variables
-static fat16_boot_sector_t boot_sector;
-static uint32_t root_dir_sector = FAT16_ROOT_DIR_SECTOR;
-
-// Read a sector from the disk using ATA
-bool read_sector(uint32_t lba, uint8_t* buffer) {
-    return ata_read_sector(lba, buffer);
-}
-
-// Write a sector to the disk using ATA
-bool write_sector(uint32_t lba, const uint8_t* buffer) {
-    return ata_write_sector(lba, buffer);
-}
-
-// Parse the boot sector to retrieve basic file system info
-bool parse_fat16_boot_sector(void) {
-    uint8_t sector_buffer[FAT16_SECTOR_SIZE];
-
-    // Read the boot sector
-    if (!read_sector(FAT16_BOOT_SECTOR, sector_buffer)) {
-        print_string("[FAT16] Failed to read boot sector\n");
-        return false;
-    }
-
-    // Cast to boot sector structure
-    memcpy(&boot_sector, sector_buffer, sizeof(fat16_boot_sector_t));
-
-    // Check for FAT16 signature
-    if (boot_sector.oem_name[0] != 'F' || boot_sector.oem_name[1] != 'A' || boot_sector.oem_name[2] != 'T') {
-        print_string("[FAT16] Invalid FAT16 boot sector signature\n");
-        return false;
-    }
-
-    print_string("[FAT16] FAT16 boot sector parsed successfully\n");
-    return true;
-}
-
-// Parse the root directory
-bool parse_fat16_root_dir(void) {
-    uint8_t sector_buffer[FAT16_SECTOR_SIZE];
-
-    for (int i = 0; i < (boot_sector.max_root_entries / (FAT16_SECTOR_SIZE / sizeof(fat16_dir_entry_t))); i++) {
-        // Read root directory sector
-        if (!read_sector(root_dir_sector + i, sector_buffer)) {
-            print_string("[FAT16] Failed to read root directory sector\n");
-            return false;
-        }
-
-        // Parse the root directory entries
-        for (int j = 0; j < (FAT16_SECTOR_SIZE / sizeof(fat16_dir_entry_t)); j++) {
-            fat16_dir_entry_t* entry = (fat16_dir_entry_t*)&sector_buffer[j * sizeof(fat16_dir_entry_t)];
-            if (entry->name[0] == 0x00) {
-                // End of directory entries
-                return true;
-            }
-            if (entry->name[0] != 0xE5) {
-                // Print file name (8.3 format)
-                char filename[12];
-                strncpy(filename, (char*)entry->name, 8);
-                filename[8] = '.';
-                strncpy(&filename[9], (char*)entry->ext, 3);
-                filename[11] = '\0';
-                print_string(filename);
-                print_string("\n");
-            }
-        }
-    }
-    return true;
-}
-
-// Read a specific directory entry from the FAT16 root directory
-bool read_fat16_entry(uint16_t entry_index, fat16_dir_entry_t* entry) {
-    uint8_t sector_buffer[FAT16_SECTOR_SIZE];
-    uint32_t sector_num = FAT16_ROOT_DIR_SECTOR + (entry_index / (FAT16_SECTOR_SIZE / sizeof(fat16_dir_entry_t)));
-    uint16_t entry_offset = entry_index % (FAT16_SECTOR_SIZE / sizeof(fat16_dir_entry_t));
-
-    // Read the sector
-    if (!read_sector(sector_num, sector_buffer)) {
-        print_string("[FAT16] Failed to read root directory sector\n");
-        return false;
-    }
-
-    // Get the entry
-    memcpy(entry, &sector_buffer[entry_offset * sizeof(fat16_dir_entry_t)], sizeof(fat16_dir_entry_t));
-    return true;
-}
-
-// Mount the FAT16 filesystem
-bool mount_fat16(void) {
-    // Parse the boot sector
-    if (!parse_fat16_boot_sector()) {
-        return false;
-    }
-
-    // Parse the root directory
-    if (!parse_fat16_root_dir()) {
-        return false;
-    }
-
-    print_string("[FAT16] Filesystem mounted successfully\n");
-    return true;
-}

kernel/fat16.h

@@ -1,60 +0,0 @@
-#ifndef FAT16_H
-#define FAT16_H
-
-#include <stdint.h>
-#include <stdbool.h>
-
-/* FAT16 Constants */
-#define FAT16_SECTOR_SIZE        512
-#define FAT16_CLUSTER_SIZE       1
-#define FAT16_MAX_FILENAME_LEN   11   // 8.3 format
-#define FAT16_ROOT_DIR_ENTRIES   224  // Fat16 root directory entries (typically 512 bytes per entry)
-
-#define FAT16_BOOT_SECTOR        0
-#define FAT16_FAT1_SECTOR        1
-#define FAT16_FAT2_SECTOR        2
-#define FAT16_ROOT_DIR_SECTOR    19  // First sector of root directory
-
-/* Boot Sector */
-typedef struct {
-    uint8_t jmp[3];               // Jump instruction to code
-    uint8_t oem_name[8];          // OEM Name
-    uint16_t bytes_per_sector;    // Bytes per sector (512)
-    uint8_t sectors_per_cluster;  // Sectors per cluster
-    uint16_t reserved_sectors;    // Reserved sectors
-    uint8_t num_fats;             // Number of FAT tables
-    uint16_t max_root_entries;    // Max number of root directory entries
-    uint16_t total_sectors_16;    // Total sectors in FAT16
-    uint8_t media_type;           // Media type (0xF8 = fixed drive)
-    uint16_t sectors_per_fat;    // Sectors per FAT table
-    uint16_t sectors_per_track;  // Sectors per track (for CHS addressing)
-    uint16_t num_heads;          // Number of heads (for CHS addressing)
-    uint32_t hidden_sectors;     // Hidden sectors (before the partition)
-    uint32_t total_sectors_32;   // Total sectors in FAT16 (extended)
-} __attribute__((packed)) fat16_boot_sector_t;
-
-/* FAT16 Directory Entry */
-typedef struct {
-    uint8_t name[8];   // File name (8 chars)
-    uint8_t ext[3];    // File extension (3 chars)
-    uint8_t attributes; // File attributes (e.g., directory, read-only)
-    uint8_t reserved;   // Reserved
-    uint8_t creation_time[2]; // Creation time
-    uint8_t creation_date[2]; // Creation date
-    uint8_t last_access_date[2]; // Last access date
-    uint8_t first_cluster_high[2]; // High part of first cluster number
-    uint8_t last_mod_time[2];  // Last modification time
-    uint8_t last_mod_date[2];  // Last modification date
-    uint8_t first_cluster_low[2];  // Low part of first cluster number
-    uint32_t file_size;         // File size in bytes
-} __attribute__((packed)) fat16_dir_entry_t;
-
-/* Function Prototypes */
-bool mount_fat16(void);
-bool read_sector(uint32_t lba, uint8_t* buffer);
-bool write_sector(uint32_t lba, const uint8_t* buffer);
-bool parse_fat16_boot_sector(void);
-bool parse_fat16_root_dir(void);
-bool read_fat16_entry(uint16_t entry_index, fat16_dir_entry_t* entry);
-
-#endif // FAT16_H

kernel/memmap.c

@@ -1,18 +1,21 @@
 #include "memmap.h"
 
-#define BOOTLOADER_MEMMAP_COUNT_ADDR    MEMMAP_BASE
-#define BOOTLOADER_MEMMAP_ADDR          (MEMMAP_BASE + 4)
-
 uint32_t get_memory_map(memory_map_entry_t *map, uint32_t max_entries) {
-    // Read the number of entries found by the bootloader
-    uint32_t entries_found = *(uint32_t*)BOOTLOADER_MEMMAP_COUNT_ADDR;
-    memory_map_entry_t *bios_data = (memory_map_entry_t*)BOOTLOADER_MEMMAP_ADDR;
-
     uint32_t count = 0;
-    while (count < entries_found && count < max_entries) {
-        map[count] = bios_data[count];
+
+    if (max_entries >= 1) {
+        map[count].base_addr = 0x00000000;
+        map[count].length = 0x0009FC00;
+        map[count].type = 1;
+        count++;
+    }
+
+    if (max_entries >= 2) {
+        map[count].base_addr = 0x00100000;
+        map[count].length = 0x1FF00000;
+        map[count].type = 1;
         count++;
     }
 
     return count;
-}
+}

kernel/memmap.h

@@ -7,7 +7,6 @@ typedef struct {
     uint64_t base_addr;
     uint64_t length;
     uint32_t type;
-    uint32_t ext;
 } __attribute__((packed)) memory_map_entry_t;
 
 uint32_t get_memory_map(memory_map_entry_t *map, uint32_t max_entries);

kernel/pci.c

@@ -1,109 +0,0 @@
-#include "pci.h"
-#include "io.h"
-
-/* --- Configuration Access Functions --- */
-
-uint32_t pci_config_read_dword(uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset) {
-    uint32_t address = (uint32_t)((uint32_t)1 << 31) | 
-                       ((uint32_t)bus << 16) | 
-                       ((uint32_t)slot << 11) | 
-                       ((uint32_t)func << 8) | 
-                       (offset & 0xFC);
-    outl(PCI_CONFIG_ADDRESS, address);
-    return inl(PCI_CONFIG_DATA);
-}
-
-void pci_config_write_dword(uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset, uint32_t data) {
-    uint32_t address = (uint32_t)((uint32_t)1 << 31) | 
-                       ((uint32_t)bus << 16) | 
-                       ((uint32_t)slot << 11) | 
-                       ((uint32_t)func << 8) | 
-                       (offset & 0xFC);
-    outl(PCI_CONFIG_ADDRESS, address);
-    outl(PCI_CONFIG_DATA, data);
-}
-
-/* To read a word or byte, we read the Dword and shift/mask */
-uint16_t pci_config_read_word(uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset) {
-    uint32_t dword = pci_config_read_dword(bus, slot, func, offset);
-    return (uint16_t)((dword >> ((offset & 2) * 8)) & 0xFFFF);
-}
-
-uint8_t pci_config_read_byte(uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset) {
-    uint32_t dword = pci_config_read_dword(bus, slot, func, offset);
-    return (uint8_t)((dword >> ((offset & 3) * 8)) & 0xFF);
-}
-
-/* --- BAR Decoding Logic --- */
-
-pci_bar_t pci_get_bar(uint8_t bus, uint8_t slot, uint8_t func, uint8_t bar_index) {
-    pci_bar_t bar = {0};
-    uint8_t offset = PCI_REG_BAR0 + (bar_index * 4);
-    
-    uint32_t initial_val = pci_config_read_dword(bus, slot, func, offset);
-    
-    // The Size Masking Trick
-    pci_config_write_dword(bus, slot, func, offset, 0xFFFFFFFF);
-    uint32_t mask = pci_config_read_dword(bus, slot, func, offset);
-    pci_config_write_dword(bus, slot, func, offset, initial_val); // Restore
-    
-    if (initial_val & 0x1) {
-        // I/O Space BAR
-        bar.is_io = true;
-        bar.base_address = initial_val & 0xFFFFFFFC;
-        bar.size = ~(mask & 0xFFFFFFFC) + 1;
-    } else {
-        // Memory Space BAR
-        bar.is_io = false;
-        bar.base_address = initial_val & 0xFFFFFFF0;
-        bar.is_prefetchable = (initial_val & 0x8) != 0;
-        bar.size = ~(mask & 0xFFFFFFF0) + 1;
-    }
-    
-    return bar;
-}
-
-/* --- Enumeration and Discovery --- */
-
-void pci_check_function(uint8_t bus, uint8_t slot, uint8_t func) {
-    uint16_t vendor_id = pci_config_read_word(bus, slot, func, PCI_REG_VENDOR_ID);
-    if (vendor_id == 0xFFFF) return; 
-
-    uint16_t device_id = pci_config_read_word(bus, slot, func, PCI_REG_DEVICE_ID);
-    uint8_t class_code = pci_config_read_byte(bus, slot, func, PCI_REG_CLASS);
-    
-    /* Optional: Set Master Latency Timer if it is 0. 
-       A value of 32 (0x20) or 64 (0x40) is typical. 
-    */
-    uint8_t latency = pci_config_read_byte(bus, slot, func, PCI_REG_LATENCY_TIMER);
-    if (latency == 0) {
-        // pci_config_write_byte would be needed here, or write a dword with the byte modified
-        uint32_t reg_0c = pci_config_read_dword(bus, slot, func, 0x0C);
-        reg_0c |= (0x20 << 8); // Set latency to 32
-        pci_config_write_dword(bus, slot, func, 0x0C, reg_0c);
-    }
-
-    // Replace with your kernel's print/logging function
-    // printf("Found PCI Device: %x:%x Class: %x at %d:%d:%d\n", vendor_id, device_id, class_code, bus, slot, func);
-}
-
-void pci_init(void) {
-    for (uint16_t bus = 0; bus < 256; bus++) {
-        for (uint8_t slot = 0; slot < 32; slot++) {
-            // Check Function 0 first
-            uint16_t vendor = pci_config_read_word(bus, slot, 0, PCI_REG_VENDOR_ID);
-            if (vendor == 0xFFFF) continue;
-
-            pci_check_function(bus, slot, 0);
-
-            // Check if this is a multi-function device
-            uint8_t header_type = pci_config_read_byte(bus, slot, 0, PCI_REG_HEADER_TYPE);
-            if (header_type & 0x80) {
-                // Check functions 1-7
-                for (uint8_t func = 1; func < 8; func++) {
-                    pci_check_function(bus, slot, func);
-                }
-            }
-        }
-    }
-}

kernel/pci.h

@@ -1,60 +0,0 @@
-#ifndef PCI_H
-#define PCI_H
-
-#include <stdint.h>
-#include <stdbool.h>
-
-/* I/O Ports for PCI Configuration Mechanism #1 */
-#define PCI_CONFIG_ADDRESS 0xCF8
-#define PCI_CONFIG_DATA    0xCFC
-
-/* Common PCI Configuration Register Offsets */
-#define PCI_REG_VENDOR_ID       0x00
-#define PCI_REG_DEVICE_ID       0x02
-#define PCI_REG_COMMAND         0x04
-#define PCI_REG_STATUS          0x06
-#define PCI_REG_REVISION_ID     0x08
-#define PCI_REG_PROG_IF         0x09
-#define PCI_REG_SUBCLASS        0x0A
-#define PCI_REG_CLASS           0x0B
-#define PCI_REG_CACHE_LINE_SIZE 0x0C
-#define PCI_REG_LATENCY_TIMER   0x0D
-#define PCI_REG_HEADER_TYPE     0x0E
-#define PCI_REG_BIST            0x0F
-#define PCI_REG_BAR0            0x10
-#define PCI_REG_BAR1            0x14
-#define PCI_REG_BAR2            0x18
-#define PCI_REG_BAR3            0x1C
-#define PCI_REG_BAR4            0x20
-#define PCI_REG_BAR5            0x24
-#define PCI_REG_INTERRUPT_LINE  0x3C
-
-typedef struct {
-    uint32_t base_address;
-    uint32_t size;
-    bool     is_io;
-    bool     is_prefetchable; // Only for Memory BARs
-} pci_bar_t;
-
-typedef struct {
-    uint8_t  bus;
-    uint8_t  device;
-    uint8_t  function;
-    uint16_t vendor_id;
-    uint16_t device_id;
-    uint8_t  class_code;
-    uint8_t  subclass;
-    uint8_t  interrupt_line;
-} pci_dev_t;
-
-/* Function Prototypes */
-uint32_t pci_config_read_dword(uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset);
-void     pci_config_write_dword(uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset, uint32_t data);
-
-uint16_t pci_config_read_word(uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset);
-uint8_t  pci_config_read_byte(uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset);
-
-pci_bar_t pci_get_bar(uint8_t bus, uint8_t slot, uint8_t func, uint8_t bar_index);
-void      pci_init(void);
-
-#endif

kernel/pic.h

@@ -0,0 +1,25 @@
+#ifndef PIC_H
+#define PIC_H
+
+#include <stdint.h>
+
+/* I/O Ports for the PICs */
+#define PIC1_COMMAND 0x20
+#define PIC1_DATA    0x21
+#define PIC2_COMMAND 0xA0
+#define PIC2_DATA    0xA1
+
+/* PIC Commands */
+#define PIC_EOI      0x20  /* End of Interrupt */
+
+/* Offset vectors for remapping */
+#define PIC1_OFFSET  0x20
+#define PIC2_OFFSET  0x28
+
+void pic_init(void);
+void pic_send_eoi(uint8_t irq);
+void pic_mask(uint8_t irq);
+void pic_unmask(uint8_t irq);
+void pic_disable(void);
+
+#endif

kernel/ps2.c

@@ -1,107 +0,0 @@
-#include "ps2.h"
-#include "io.h"
-
-/* --- Controller Synchronization --- */
-
-// Wait until the controller is ready to receive a byte
-static void ps2_wait_write() {
-    while (inb(PS2_STATUS_REG) & PS2_STATUS_INPUT);
-}
-
-// Wait until the controller has a byte for us to read
-static void ps2_wait_read() {
-    while (!(inb(PS2_STATUS_REG) & PS2_STATUS_OUTPUT));
-}
-
-/* --- Initialization --- */
-
-void ps2_write_device(uint8_t command) {
-    ps2_wait_write();
-    outb(PS2_DATA_PORT, command);
-}
-
-void ps2_write_mouse(uint8_t data) {
-    ps2_wait_write();
-    outb(PS2_COMMAND_REG, PS2_CMD_WRITE_MOUSE); // "Next byte goes to mouse"
-    ps2_wait_write();
-    outb(PS2_DATA_PORT, data);
-}
-
-void ps2_init(void) {
-    // 1. Disable Devices
-    ps2_wait_write();
-    outb(PS2_COMMAND_REG, PS2_CMD_DISABLE_KB);
-    ps2_wait_write();
-    outb(PS2_COMMAND_REG, PS2_CMD_DISABLE_MS);
-
-    // 2. Flush Output Buffer
-    while (inb(PS2_STATUS_REG) & PS2_STATUS_OUTPUT) {
-        inb(PS2_DATA_PORT);
-    }
-
-    // 3. Set Controller Configuration Byte
-    // Bit 0: KB Interrupt, Bit 1: Mouse Interrupt, Bit 6: Translation
-    ps2_wait_write();
-    outb(PS2_COMMAND_REG, PS2_CMD_READ_CONFIG);
-    ps2_wait_read();
-    uint8_t status = inb(PS2_DATA_PORT);
-    status |= (1 << 0) | (1 << 1); // Enable IRQ 1 and IRQ 12
-    
-    ps2_wait_write();
-    outb(PS2_COMMAND_REG, PS2_CMD_WRITE_CONFIG);
-    ps2_wait_write();
-    outb(PS2_DATA_PORT, status);
-
-    // 4. Enable Devices
-    ps2_wait_write();
-    outb(PS2_COMMAND_REG, PS2_CMD_ENABLE_KB);
-    ps2_wait_write();
-    outb(PS2_COMMAND_REG, PS2_CMD_ENABLE_MS);
-
-    // 5. Initialize Mouse (The mouse won't send IRQs until you tell it to)
-    ps2_write_mouse(MOUSE_CMD_SET_DEFAULTS);
-    ps2_wait_read(); inb(PS2_DATA_PORT); // Read ACK (0xFA)
-    
-    ps2_write_mouse(MOUSE_CMD_ENABLE_SCAN);
-    ps2_wait_read(); inb(PS2_DATA_PORT); // Read ACK (0xFA)
-}
-
-/* --- IRQ Handlers --- */
-
-// Called from IRQ 1 (Keyboard)
-void ps2_keyboard_handler(void) {
-    uint8_t scancode = inb(PS2_DATA_PORT);
-    // Process scancode (e.g., put it into a circular buffer)
-}
-
-// Called from IRQ 12 (Mouse)
-static uint8_t mouse_cycle = 0;
-static uint8_t mouse_bytes[3];
-
-void ps2_mouse_handler(void) {
-    uint8_t status = inb(PS2_STATUS_REG);
-    
-    // Ensure this is actually mouse data
-    if (!(status & PS2_STATUS_MOUSE)) return;
-
-    mouse_bytes[mouse_cycle++] = inb(PS2_DATA_PORT);
-
-    if (mouse_cycle == 3) {
-        mouse_cycle = 0;
-        
-        // Byte 0: Flags (Buttons, Signs)
-        // Byte 1: X Delta
-        // Byte 2: Y Delta
-        
-        mouse_state_t state;
-        state.left_button   = (mouse_bytes[0] & 0x01);
-        state.right_button  = (mouse_bytes[0] & 0x02);
-        state.middle_button = (mouse_bytes[0] & 0x04);
-
-        // Handle negative deltas (signed 9-bit logic)
-        state.x_delta = (int8_t)mouse_bytes[1];
-        state.y_delta = (int8_t)mouse_bytes[2];
-
-        // Update your kernel's internal mouse position here
-    }
-}

kernel/ps2.h

@@ -1,45 +0,0 @@
-#ifndef PS2_H
-#define PS2_H
-
-#include <stdint.h>
-#include <stdbool.h>
-
-/* I/O Ports */
-#define PS2_DATA_PORT       0x60
-#define PS2_STATUS_REG      0x64
-#define PS2_COMMAND_REG     0x64
-
-/* Status Register Bits */
-#define PS2_STATUS_OUTPUT   0x01 // 1 = Data ready to be read
-#define PS2_STATUS_INPUT    0x02 // 1 = Controller busy, don't write yet
-#define PS2_STATUS_SYS      0x04 // System flag
-#define PS2_STATUS_CMD_DATA 0x08 // 0 = Data written to 0x60, 1 = Cmd to 0x64
-#define PS2_STATUS_MOUSE    0x20 // 1 = Mouse data, 0 = Keyboard data
-
-/* Controller Commands */
-#define PS2_CMD_READ_CONFIG  0x20
-#define PS2_CMD_WRITE_CONFIG 0x60
-#define PS2_CMD_DISABLE_MS   0xA7
-#define PS2_CMD_ENABLE_MS    0xA8
-#define PS2_CMD_DISABLE_KB   0xAD
-#define PS2_CMD_ENABLE_KB    0xAE
-#define PS2_CMD_WRITE_MOUSE  0xD4
-
-/* Mouse Commands */
-#define MOUSE_CMD_SET_DEFAULTS 0xF6
-#define MOUSE_CMD_ENABLE_SCAN  0xF4
-
-typedef struct {
-    int8_t  x_delta;
-    int8_t  y_delta;
-    bool    left_button;
-    bool    right_button;
-    bool    middle_button;
-} mouse_state_t;
-
-/* Public API */
-void ps2_init(void);
-void ps2_keyboard_handler(void);
-void ps2_mouse_handler(void);
-
-#endif

kernel/threading.c

@@ -4,8 +4,8 @@
 #include "print.h"
 #include "threading.h"
 
-#define MAX_THREADS 16          // Maximum number of threads
-#define THREAD_STACK_SIZE 8192  // Stack size for each thread
+#define MAX_THREADS 16           // Maximum number of threads
+#define THREAD_STACK_SIZE 8192   // Stack size for each thread
 
 // The thread table stores information about all threads
 static Thread thread_table[MAX_THREADS];
@@ -16,106 +16,103 @@ static uint32_t num_threads = 0;     // Number of active threads
 static volatile int mutex_locked = 0;
 
 // Function declaration for context_switch
-void context_switch(Thread* next);
+void context_switch(Thread *next);
 
 // Initialize the threading system
 void thread_init(void) {
-  memset(thread_table, 0, sizeof(thread_table));
-  num_threads = 0;
+    memset(thread_table, 0, sizeof(thread_table));
+    num_threads = 0;
 }
 
 // Create a new thread
-void thread_create(Thread* thread __attribute__((unused)),
-                   void (*start_routine)(void*), void* arg) {
-  if (num_threads >= MAX_THREADS) {
-    my_printf("Error: Maximum thread count reached.\n");
-    return;
-  }
+void thread_create(Thread *thread __attribute__((unused)), void (*start_routine)(void *), void *arg) {
+    if (num_threads >= MAX_THREADS) {
+        my_printf("Error: Maximum thread count reached.\n");
+        return;
+    }
 
-  // Find an empty slot for the new thread
-  int index = num_threads++;
-  thread_table[index] = (Thread){0};
+    // Find an empty slot for the new thread
+    int index = num_threads++;
+    thread_table[index] = (Thread){0};
+    
+    // Set up the new thread
+    thread_table[index].start_routine = start_routine;
+    thread_table[index].arg = arg;
+    thread_table[index].stack_size = THREAD_STACK_SIZE;
+    thread_table[index].stack = (uint32_t*)malloc(THREAD_STACK_SIZE);
+    thread_table[index].stack_top = thread_table[index].stack + THREAD_STACK_SIZE / sizeof(uint32_t);
 
-  // Set up the new thread
-  thread_table[index].start_routine = start_routine;
-  thread_table[index].arg = arg;
-  thread_table[index].stack_size = THREAD_STACK_SIZE;
-  thread_table[index].stack = (uint32_t*)malloc(THREAD_STACK_SIZE);
-  thread_table[index].stack_top =
-      thread_table[index].stack + THREAD_STACK_SIZE / sizeof(uint32_t);
+    // Initialize the stack (simulate pushing the function's return address)
+    uint32_t *stack_top = thread_table[index].stack_top;
+    *(--stack_top) = (uint32_t)start_routine;  // Return address (the thread's entry point)
+    *(--stack_top) = (uint32_t)arg;            // Argument to pass to the thread
 
-  // Initialize the stack (simulate pushing the function's return address)
-  uint32_t* stack_top = thread_table[index].stack_top;
-  *(--stack_top) =
-      (uint32_t)start_routine;     // Return address (the thread's entry point)
-  *(--stack_top) = (uint32_t)arg;  // Argument to pass to the thread
+    // Set the thread's state to ready
+    thread_table[index].state = THREAD_READY;
 
-  // Set the thread's state to ready
-  thread_table[index].state = THREAD_READY;
-
-  // If this is the first thread, switch to it
-  if (index == 0) {
-    scheduler();
-  }
+    // If this is the first thread, switch to it
+    if (index == 0) {
+        scheduler();
+    }
 }
 
 // Yield the CPU to another thread
 void thread_yield(void) {
-  // Find the next thread in a round-robin manner
-  uint32_t next_thread = (current_thread + 1) % num_threads;
-  while (next_thread != current_thread &&
-         thread_table[next_thread].state != THREAD_READY) {
-    next_thread = (next_thread + 1) % num_threads;
-  }
+    // Find the next thread in a round-robin manner
+    uint32_t next_thread = (current_thread + 1) % num_threads;
+    while (next_thread != current_thread && thread_table[next_thread].state != THREAD_READY) {
+        next_thread = (next_thread + 1) % num_threads;
+    }
 
-  if (next_thread != current_thread) {
-    current_thread = next_thread;
-    scheduler();
-  }
+    if (next_thread != current_thread) {
+        current_thread = next_thread;
+        scheduler();
+    }
 }
 
 // Exit the current thread
 void thread_exit(void) {
-  thread_table[current_thread].state =
-      THREAD_BLOCKED;  // Mark the thread as blocked (finished)
-  free(thread_table[current_thread].stack);  // Free the thread's stack
-  num_threads--;                             // Decrease thread count
+    thread_table[current_thread].state = THREAD_BLOCKED;  // Mark the thread as blocked (finished)
+    free(thread_table[current_thread].stack);             // Free the thread's stack
+    num_threads--;                                       // Decrease thread count
 
-  // Yield to the next thread
-  thread_yield();
+    // Yield to the next thread
+    thread_yield();
 }
 
 // Scheduler: This function selects the next thread to run
 void scheduler(void) {
-  // Find the next ready thread
-  uint32_t next_thread = (current_thread + 1) % num_threads;
-  while (thread_table[next_thread].state != THREAD_READY) {
-    next_thread = (next_thread + 1) % num_threads;
-  }
+    // Find the next ready thread
+    uint32_t next_thread = (current_thread + 1) % num_threads;
+    while (thread_table[next_thread].state != THREAD_READY) {
+        next_thread = (next_thread + 1) % num_threads;
+    }
 
-  if (next_thread != current_thread) {
-    current_thread = next_thread;
-    context_switch(&thread_table[current_thread]);
-  }
+    if (next_thread != current_thread) {
+        current_thread = next_thread;
+        context_switch(&thread_table[current_thread]);
+    }
 }
 
-// Context switch to the next thread (assembly would go here to save/load
-// registers)
-void context_switch(Thread* next) {
-  // For simplicity, context switching in this example would involve
-  // saving/restoring registers. In a real system, you would need to save the
-  // CPU state (registers) and restore the next thread's state.
-  my_printf("Switching to thread...\n");
-  next->start_routine(next->arg);  // Start running the next thread
+// Context switch to the next thread (assembly would go here to save/load registers)
+void context_switch(Thread *next) {
+    // For simplicity, context switching in this example would involve saving/restoring registers.
+    // In a real system, you would need to save the CPU state (registers) and restore the next thread's state.
+    my_printf("Switching to thread...\n");
+    next->start_routine(next->arg);  // Start running the next thread
 }
 
 // Simple mutex functions (spinlock)
-void mutex_init(void) { mutex_locked = 0; }
-
-void mutex_lock(void) {
-  while (__sync_lock_test_and_set(&mutex_locked, 1)) {
-    // Busy wait (spinlock)
-  }
+void mutex_init(void) {
+    mutex_locked = 0;
 }
 
-void mutex_unlock(void) { __sync_lock_release(&mutex_locked); }
+void mutex_lock(void) {
+    while (__sync_lock_test_and_set(&mutex_locked, 1)) {
+        // Busy wait (spinlock)
+    }
+}
+
+void mutex_unlock(void) {
+    __sync_lock_release(&mutex_locked);
+}

klibc/include/string.h

@@ -3,13 +3,12 @@
 
 #include <stddef.h>
 
-extern int memcmp(const void *s1, const void *s2, size_t n);
-extern void *memmove(void *dst, const void *src, size_t n);
-extern void *memcpy(void *dst, const void *src, size_t n);
-extern void *memset(void *dst, int c, size_t n);
+extern int memcmp(const void* s1, const void* s2, size_t n);
+extern void* memmove(void* dst, const void* src, size_t n);
+extern void* memcpy(void* dst, const void* src, size_t n);
+extern void* memset(void* dst, int c, size_t n);
 
-extern size_t strlen(const char *s);
-extern int strcmp(const char *s1, const char *s2);
-extern char *strncpy(char *dst, const char *src, size_t n);
+extern size_t strlen(const char* s);
+extern int strcmp(const char* s1, const char* s2);
 
 #endif  // CLASSICOS_KLIBC_STRING_H

klibc/src/string.c

@@ -1,8 +1,8 @@
 #include <string.h>
 
-int memcmp(const void *s1, const void *s2, size_t n) {
-    const unsigned char *c1 = s1;
-    const unsigned char *c2 = s2;
+int memcmp(const void* s1, const void* s2, size_t n) {
+    const unsigned char* c1 = s1;
+    const unsigned char* c2 = s2;
     int d = 0;
 
     while (n--) {
@@ -13,9 +13,9 @@ int memcmp(const void *s1, const void *s2, size_t n) {
     return d;
 }
 
-void *memmove(void *dst, const void *src, size_t n) {
-    const char *p = src;
-    char *q = dst;
+void* memmove(void* dst, const void* src, size_t n) {
+    const char* p = src;
+    char* q = dst;
 #if defined(__i386__) || defined(__x86_64__)
     if (q < p) {
         __asm__ volatile("cld; rep; movsb" : "+c"(n), "+S"(p), "+D"(q));
@@ -41,19 +41,19 @@ void *memmove(void *dst, const void *src, size_t n) {
     return dst;
 }
 
-void *memcpy(void *dst, const void *src, size_t n) {
-    const char *p = src;
-    char *q = dst;
+void* memcpy(void* dst, const void* src, size_t n) {
+    const char* p = src;
+    char* q = dst;
 #if defined(__i386__)
     size_t nl = n >> 2;
     __asm__ volatile("cld ; rep ; movsl ; movl %3,%0 ; rep ; movsb"
-                     : "+c"(nl), "+S"(p), "+D"(q)
-                     : "r"(n & 3));
+                    : "+c"(nl), "+S"(p), "+D"(q)
+                    : "r"(n & 3));
 #elif defined(__x86_64__)
     size_t nq = n >> 3;
     __asm__ volatile("cld ; rep ; movsq ; movl %3,%%ecx ; rep ; movsb"
-                     : "+c"(nq), "+S"(p), "+D"(q)
-                     : "r"((uint32_t)(n & 7)));
+                    : "+c"(nq), "+S"(p), "+D"(q)
+                    : "r"((uint32_t)(n & 7)));
 #else
     while (n--) {
         *q++ = *p++;
@@ -63,20 +63,20 @@ void *memcpy(void *dst, const void *src, size_t n) {
     return dst;
 }
 
-void *memset(void *dst, int c, size_t n) {
-    char *q = dst;
+void* memset(void* dst, int c, size_t n) {
+    char* q = dst;
 
 #if defined(__i386__)
     size_t nl = n >> 2;
     __asm__ volatile("cld ; rep ; stosl ; movl %3,%0 ; rep ; stosb"
-                     : "+c"(nl), "+D"(q)
-                     : "a"((unsigned char)c * 0x01010101U), "r"(n & 3));
+                    : "+c"(nl), "+D"(q)
+                    : "a"((unsigned char)c * 0x01010101U), "r"(n & 3));
 #elif defined(__x86_64__)
     size_t nq = n >> 3;
     __asm__ volatile("cld ; rep ; stosq ; movl %3,%%ecx ; rep ; stosb"
-                     : "+c"(nq), "+D"(q)
-                     : "a"((unsigned char)c * 0x0101010101010101U),
-                       "r"((uint32_t)n & 7));
+                    : "+c"(nq), "+D"(q)
+                    : "a"((unsigned char)c * 0x0101010101010101U),
+                      "r"((uint32_t)n & 7));
 #else
     while (n--) {
         *q++ = c;
@@ -86,15 +86,15 @@ void *memset(void *dst, int c, size_t n) {
     return dst;
 }
 
-size_t strlen(const char *s) {
-    const char *ss = s;
+size_t strlen(const char* s) {
+    const char* ss = s;
     while (*ss) ss++;
     return ss - s;
 }
 
-int strcmp(const char *s1, const char *s2) {
-    const unsigned char *c1 = (const unsigned char *)s1;
-    const unsigned char *c2 = (const unsigned char *)s2;
+int strcmp(const char* s1, const char* s2) {
+    const unsigned char* c1 = (const unsigned char*)s1;
+    const unsigned char* c2 = (const unsigned char*)s2;
     unsigned char ch;
     int d = 0;
 
@@ -105,19 +105,3 @@ int strcmp(const char *s1, const char *s2) {
 
     return d;
 }
-
-char *strncpy(char *dst, const char *src, size_t n) {
-    char *q = dst;
-    const char *p = src;
-    char ch;
-
-    while (n) {
-        n--;
-        *q++ = ch = *p++;
-        if (!ch) break;
-    }
-
-    memset(q, 0, n);
-
-    return dst;
-}

pic.c

@@ -0,0 +1,76 @@
+#include "pic.h"
+#include "io.h"
+
+/* Small delay for older hardware bus timing */
+static inline void io_wait(void) {
+    outb(0x80, 0); 
+}
+
+void pic_init(void) {
+    uint8_t a1, a2;
+
+    // Save current masks
+    a1 = inb(PIC1_DATA);
+    a2 = inb(PIC2_DATA);
+
+    // ICW1: Start initialization in cascade mode
+    outb(PIC1_COMMAND, 0x11);
+    io_wait();
+    outb(PIC2_COMMAND, 0x11);
+    io_wait();
+
+    // ICW2: Master PIC vector offset
+    outb(PIC1_DATA, PIC1_OFFSET);
+    io_wait();
+    // ICW2: Slave PIC vector offset
+    outb(PIC2_DATA, PIC2_OFFSET);
+    io_wait();
+
+    // ICW3: Tell Master there is a slave at IRQ2 (0000 0100)
+    outb(PIC1_DATA, 4);
+    io_wait();
+    // ICW3: Tell Slave its cascade identity (0000 0010)
+    outb(PIC2_DATA, 2);
+    io_wait();
+
+    // ICW4: Set 8086/88 mode
+    outb(PIC1_DATA, 0x01);
+    io_wait();
+    outb(PIC2_DATA, 0x01);
+    io_wait();
+
+    // Restore masks (or disable all to start clean)
+    outb(PIC1_DATA, 0xFB); // Keep IRQ2 (cascade) open
+    outb(PIC2_DATA, 0xFF);
+}
+
+void pic_send_eoi(uint8_t irq) {
+    if (irq >= 8) {
+        outb(PIC2_COMMAND, PIC_EOI);
+    }
+    outb(PIC1_COMMAND, PIC_EOI);
+}
+
+void pic_unmask(uint8_t irq) {
+    uint16_t port;
+    if (irq < 8) {
+        port = PIC1_DATA;
+    } else {
+        port = PIC2_DATA;
+        irq -= 8;
+    }
+    uint8_t value = inb(port) & ~(1 << irq);
+    outb(port, value);
+}
+
+void pic_mask(uint8_t irq) {
+    uint16_t port;
+    if (irq < 8) {
+        port = PIC1_DATA;
+    } else {
+        port = PIC2_DATA;
+        irq -= 8;
+    }
+    uint8_t value = inb(port) | (1 << irq);
+    outb(port, value);
+}