Create ata.h

implement the base ata pio mode driver so that the filesystems like fat16, fat32 work. This is the header for that. It will need a iso9660 driver for cdrom etc optical media

.clang-format

@@ -0,0 +1,24 @@
+BasedOnStyle: Google
+IndentWidth: 4
+TabWidth: 4
+UseTab: Never
+ColumnLimit: 80
+
+DerivePointerAlignment: false
+PointerAlignment: Right
+ReferenceAlignment: Right
+
+AlignConsecutiveMacros: Consecutive
+AlignTrailingComments:
+  Kind: Always
+  OverEmptyLines: 0
+
+IncludeBlocks: Regroup
+IncludeCategories:
+  # Std headers
+  - Regex: '<[[:alnum:]_.]+>'
+    Priority: 2
+
+  # Other headers
+  - Regex: '.*'
+    Priority: 1

.clangd

@@ -0,0 +1,6 @@
+CompileFlags:
+  CompilationDatabase: build
+
+Diagnostics:
+  UnusedIncludes: Strict
+  MissingIncludes: Strict

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[Makefile]
+indent_style = tab
+indent_size = 8
+tab_width = 8

Makefile

@@ -18,9 +18,9 @@ KERNEL_OBJ += $(patsubst kernel/%.asm, $(BUILD_DIR)/asm_%.o, $(KERNEL_ASM_SRC))
 KLIBC_SRC = $(wildcard klibc/src/*.c)
 KLIBC_OBJ = $(patsubst klibc/src/%.c, $(BUILD_DIR)/klibc/%.o, $(KLIBC_SRC))
 
+.PHONY: all stage1 stage2 kernel compile-commands $(BUILD_DIR)/compile_commands.json run gdb clean clean-cross clean-all
 all: $(DISK_IMG)
 
-.PHONY: stage1 stage2 kernel run gdb clean
 stage1: $(BUILD_DIR)
 	$(AS) $(ASFLAGS) -o $(BUILD_DIR)/$@.o bootloader/$@.asm
 	$(LD) -Ttext=0x7c00 -melf_i386 -o $(BUILD_DIR)/$@.elf $(BUILD_DIR)/$@.o
@@ -57,6 +57,10 @@ $(BUILD_DIR):
 	mkdir -p $@
 	mkdir -p $(BUILD_DIR)/klibc
 
+compile-commands: $(BUILD_DIR)/compile_commands.json
+$(BUILD_DIR)/compile_commands.json: $(BUILD_DIR)
+	bear --output $@ -- make -B
+
 run:
 	qemu-system-i386 -s -S $(DISK_IMG)
 

kernel/ata.h

@@ -0,0 +1,43 @@
+#ifndef ATA_H
+#define ATA_H
+
+#include <stdint.h>
+#include <stdbool.h>
+
+/* ATA I/O ports */
+#define ATA_PRIMARY_IO     0x1F0
+#define ATA_PRIMARY_CTRL   0x3F6
+
+/* ATA registers */
+#define ATA_REG_DATA       0x00
+#define ATA_REG_ERROR      0x01
+#define ATA_REG_FEATURES   0x01
+#define ATA_REG_SECCOUNT0  0x02
+#define ATA_REG_LBA0       0x03
+#define ATA_REG_LBA1       0x04
+#define ATA_REG_LBA2       0x05
+#define ATA_REG_HDDEVSEL   0x06
+#define ATA_REG_COMMAND    0x07
+#define ATA_REG_STATUS     0x07
+
+/* ATA commands */
+#define ATA_CMD_READ_PIO   0x20
+#define ATA_CMD_WRITE_PIO  0x30
+#define ATA_CMD_IDENTIFY   0xEC
+
+/* Status flags */
+#define ATA_SR_BSY         0x80
+#define ATA_SR_DRDY        0x40
+#define ATA_SR_DRQ         0x08
+#define ATA_SR_ERR         0x01
+
+/* Drive select */
+#define ATA_MASTER         0x00
+#define ATA_SLAVE          0x10
+
+/* Public API */
+bool ata_init(void);
+bool ata_read_sector(uint32_t lba, uint8_t* buffer);
+bool ata_write_sector(uint32_t lba, const uint8_t* buffer);
+
+#endif

kernel/hid.c

@@ -1,65 +0,0 @@
-#include "hid.h"
-#include "usb.h"
-#include "mouse.h"
-#include "keyboard.h"
-#include "print.h"
-#include <stdint.h>
-#include <stdbool.h>
-
-// Global variables
-static bool hid_initialized = false;
-
-void hid_init(void) {
-    if (hid_initialized) return;
-    hid_initialized = true;
-
-    // Initialize keyboard and mouse HID handling
-    keyboard_init();
-    // Assume USB mouse has been initialized and is connected.
-    usb_hid_init(); // Initializes USB HID for both keyboard and mouse
-}
-
-void hid_process_report(uint8_t* report, uint8_t length) {
-    // Process the HID report based on its type
-    if (length == 8) {  // Assuming a standard 8-byte report for HID keyboard
-        keyboard_hid_report_t* k_report = (keyboard_hid_report_t*) report;
-        hid_process_keyboard_report(k_report);
-    } else if (length == 3) {  // Assuming a standard 3-byte report for HID mouse
-        mouse_hid_report_t* m_report = (mouse_hid_report_t*) report;
-        hid_process_mouse_report(m_report);
-    }
-}
-
-// Handle HID keyboard report
-void hid_process_keyboard_report(const keyboard_hid_report_t* report) {
-    // Iterate over the keycodes and process key presses
-    for (int i = 0; i < 6; i++) {
-        uint8_t keycode = report->keycodes[i];
-        if (keycode != 0) {
-            char key = scancode_map[keycode];
-            if (key) {
-                keyboard_buffer_add(key);
-            }
-        }
-    }
-}
-
-// Handle HID mouse report
-void hid_process_mouse_report(const mouse_hid_report_t* report) {
-    // Process mouse movement and button clicks
-    mouse_data.x += report->x;
-    mouse_data.y += report->y;
-    mouse_data.left_button = (report->buttons & 0x01) != 0;
-    mouse_data.right_button = (report->buttons & 0x02) != 0;
-
-    print_hex((uint32_t)mouse_data.x, 1, 1);
-    print_hex((uint32_t)mouse_data.y, 1, 1);
-    print_hex((uint32_t)report->buttons, 1, 1);
-}
-
-// Parse the HID descriptor (for parsing USB HID device descriptors)
-bool hid_parse_descriptor(uint8_t* descriptor, uint32_t length) {
-    // HID descriptors are defined in the USB HID specification, we'll need to parse them here.
-    // For now, just return true assuming we have a valid descriptor.
-    return true;
-}

kernel/hid.h

@@ -1,46 +0,0 @@
-#ifndef HID_H
-#define HID_H
-
-#include <stdint.h>
-#include <stdbool.h>
-
-// HID Report types
-#define HID_REPORT_INPUT  0x01
-#define HID_REPORT_OUTPUT 0x02
-#define HID_REPORT_FEATURE 0x03
-
-// HID usage page constants (USB HID)
-#define HID_USAGE_PAGE_GENERIC 0x01
-#define HID_USAGE_KEYBOARD 0x06
-#define HID_USAGE_MOUSE 0x02
-
-// HID keyboard and mouse data
-typedef struct {
-    uint8_t modifier;    // Modifier keys (shift, ctrl, alt, etc.)
-    uint8_t reserved;    // Reserved byte
-    uint8_t keycodes[6]; // Keycodes for keys pressed
-} keyboard_hid_report_t;
-
-typedef struct {
-    uint8_t buttons;     // Mouse buttons (bitwise: 0x01 = left, 0x02 = right, 0x04 = middle)
-    int8_t x;            // X axis movement
-    int8_t y;            // Y axis movement
-    int8_t wheel;        // Mouse wheel
-} mouse_hid_report_t;
-
-// Initialize the HID subsystem
-void hid_init(void);
-
-// Process an incoming HID report
-void hid_process_report(uint8_t* report, uint8_t length);
-
-// Process HID keyboard report
-void hid_process_keyboard_report(const keyboard_hid_report_t* report);
-
-// Process HID mouse report
-void hid_process_mouse_report(const mouse_hid_report_t* report);
-
-// USB HID report descriptor parsing
-bool hid_parse_descriptor(uint8_t* descriptor, uint32_t length);
-
-#endif // HID_H

kernel/keyboard.c

@@ -2,91 +2,64 @@
 #include "io.h"
 #include "isr.h"
 #include "terminal.h"
-#include <stddef.h>
 
 #define KEYBOARD_DATA_PORT 0x60
 #define KEY_BUFFER_SIZE 256
 
-// Use volatile so the compiler knows these change inside interrupts
-static volatile char key_buffer[KEY_BUFFER_SIZE];
-static volatile uint8_t buffer_head = 0;
-static volatile uint8_t buffer_tail = 0;
-static volatile uint8_t buffer_count = 0;
+static char key_buffer[KEY_BUFFER_SIZE];
+static uint8_t buffer_head = 0;  // Write position (interrupt)
+static uint8_t buffer_tail = 0;  // Read position (get_char)
+static uint8_t buffer_count = 0;
+static uint8_t buffer_index = 0;
 
-// Exported map: Removed 'static' so hid.c can reference it if needed
-const char scancode_map[128] = {
-    0,  27, '1', '2', '3', '4', '5', '6', '7', '8',
-    '9', '0', '-', '=', '\b', '\t', 'q', 'w', 'e', 'r',
-    't', 'y', 'u', 'i', 'o', 'p', '[', ']', '\n', 0,
-    'a', 's', 'd', 'f', 'g', 'h', 'j', 'k', 'l', ';',
-    '\'', '`', 0, '\\', 'z', 'x', 'c', 'v', 'b', 'n',
-    'm', ',', '.', '/', 0, '*', 0, ' ', 0
+// Basic US QWERTY keymap (scancode to ASCII)
+static const char scancode_map[128] = {
+    0,  27, '1', '2', '3', '4', '5', '6', '7', '8', // 0x00 - 0x09
+   '9', '0', '-', '=', '\b', '\t', 'q', 'w', 'e', 'r', // 0x0A - 0x13
+   't', 'y', 'z', 'u', 'i', 'o', 'p', '[', ']', '\n', // 0x14 - 0x1D
+    0, 'a', 's', 'd', 'f', 'g', 'h', 'j', 'k', 'l', // 0x1E - 0x27
+   ';', '\'', '`', 0, '\\', 'x', 'c', 'v', 'b', // 0x28 - 0x31
+   'n', 'm', ',', '.', '/', 0, '*', 0, ' ', 0,      // 0x32 - 0x3B
+    // rest can be filled as needed
 };
 
-/**
- * Shared function used by both PS/2 (callback) and USB (hid.c)
- * This fixes the "undefined reference to keyboard_buffer_add" error.
- */
-void keyboard_buffer_add(char c) {
+// Interrupt handler for IRQ1
+void keyboard_callback(void) {
+    uint8_t scancode = inb(KEYBOARD_DATA_PORT);
+
+    if (scancode & 0x80) return;  // Ignore key release
+
+    char c = scancode_map[scancode];
     if (!c) return;
 
     uint8_t next_head = (buffer_head + 1) % KEY_BUFFER_SIZE;
 
-    // If buffer is full, we must drop the key
-    if (next_head == buffer_tail) {
-        return; 
-    }
+    // Drop key if buffer full
+    if (next_head == buffer_tail) return;
 
     key_buffer[buffer_head] = c;
     buffer_head = next_head;
     buffer_count++;
 
-    // Echo to terminal
     terminal_putchar(c);
 }
 
-/**
- * Hardware Interrupt Handler for PS/2
- */
-void keyboard_callback(void) {
-    uint8_t scancode = inb(KEYBOARD_DATA_PORT);
-
-    // Ignore break codes (key release)
-    if (scancode & 0x80) return; 
-
-    char c = scancode_map[scancode];
-    keyboard_buffer_add(c);
+void keyboard_init() {
+    register_interrupt_handler(33, keyboard_callback); // IRQ1 = int 33 (0x21)
 }
 
-void keyboard_init(void) {
-    buffer_head = 0;
-    buffer_tail = 0;
-    buffer_count = 0;
-    // IRQ1 is usually mapped to IDT entry 33
-    register_interrupt_handler(33, keyboard_callback); 
-}
-
-/**
- * Blocking read with a safe HLT to prevent CPU 100% usage
- */
+// Blocking read (returns one char)
 char keyboard_get_char(void) {
-    char c;
-
-    while (1) {
-        __asm__ __volatile__("cli"); // Disable interrupts to check buffer_count safely
-        
-        if (buffer_count > 0) {
-            c = key_buffer[buffer_tail];
-            buffer_tail = (buffer_tail + 1) % KEY_BUFFER_SIZE;
-            buffer_count--;
-            __asm__ __volatile__("sti"); // Re-enable interrupts after reading
-            return c;
-        }
-
-        /* * IMPORTANT: 'sti' followed by 'hlt' is guaranteed by x86 
-         * to execute 'hlt' BEFORE the next interrupt can trigger.
-         * This prevents the race condition hang.
-         */
-        __asm__ __volatile__("sti; hlt"); 
+    while (buffer_count == 0) {
+        __asm__ __volatile__("hlt");  // Better than busy loop
     }
+
+    char c;
+    __asm__ __volatile__("cli");
+    c = key_buffer[buffer_tail];
+    buffer_tail = (buffer_tail + 1) % KEY_BUFFER_SIZE;
+    buffer_count--;
+    __asm__ __volatile__("sti");
+
+    return c;
 }

kernel/keyboard.h

@@ -1,12 +1,7 @@
 #ifndef KEYBOARD_H
 #define KEYBOARD_H
 
-#include <stdint.h>
-
 void keyboard_init(void);
-void keyboard_buffer_add(char c);
-char keyboard_get_char(void);  
-
-extern const char scancode_map[128]; 
+char keyboard_get_char(void);  // Blocking read from buffer
 
 #endif

kernel/mouse.c

@@ -5,7 +5,7 @@
 #include <stdbool.h>
 
 // Mouse buffer
-mouse_data_t mouse_data;
+static mouse_data_t mouse_data;
 
 // Read USB mouse data
 mouse_data_t usb_read_mouse(void) {

kernel/mouse.h

@@ -12,8 +12,6 @@ typedef struct {
     bool right_button;
 } mouse_data_t;
 
-extern mouse_data_t mouse_data;
-
 // Function declarations for USB 1.x HID mouse support
 bool usb_mouse_init(void);
 bool usb_mouse_detected(void);