Create vesa.h

Add header for the base VLB VBE VESA driver

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/vesa.c

@@ -0,0 +1,98 @@
+#include "vesa.h"
+#include "io.h"
+#include "print.h"
+
+// VESA mode and controller information
+#define VESA_BIOS_INT 0x10
+#define VESA_BIOS_FUNC 0x4F
+
+// Function to call BIOS with specific VESA function
+static bool vesa_bios_call(uint16_t function, uint16_t* eax, uint32_t* ebx, uint32_t* ecx, uint32_t* edx) {
+    // Set up registers for VESA function call
+    __asm__ __volatile__(
+        "movw %1, %%ax\n"           // Move function number into AX
+        "int $0x10\n"                // Call BIOS interrupt 0x10 (VESA)
+        "movw %%ax, %0\n"            // Move return value in AX to the return variable
+        : "=m"(*eax)                 // Output operand (eax)
+        : "m"(function)              // Input operand (function number)
+        : "%eax", "%ebx", "%ecx", "%edx", "memory"
+    );
+    // Check for success (return values vary depending on the function)
+    return *eax == 0x004F;
+}
+
+// Set the VESA video mode
+bool vesa_set_mode(uint16_t mode) {
+    uint16_t eax = VBE_FUNCTION_SET_MODE;
+    uint32_t ebx = mode;
+    uint32_t ecx = 0;
+    uint32_t edx = 0;
+    
+    if (vesa_bios_call(VBE_FUNCTION_SET_MODE, &eax, &ebx, &ecx, &edx)) {
+        return true;
+    }
+    return false;
+}
+
+// Get the VESA mode information
+bool vesa_get_mode_info(uint16_t mode, vbe_mode_info_t* info) {
+    uint16_t eax = VBE_FUNCTION_GET_MODE_INFO;
+    uint32_t ebx = mode;
+    uint32_t ecx = 0;
+    uint32_t edx = 0;
+
+    if (vesa_bios_call(VBE_FUNCTION_GET_MODE_INFO, &eax, &ebx, &ecx, &edx)) {
+        // Copy the information into the provided struct
+        uint32_t base = (uint32_t)info;
+        __asm__ __volatile__(
+            "movw %%bx, %%es:%%di\n"
+            : 
+            : "b" (base)
+            : "%es", "%di", "memory"
+        );
+        return true;
+    }
+    return false;
+}
+
+// Get the VESA controller information
+bool vesa_get_controller_info(vbe_controller_info_t* info) {
+    uint16_t eax = VBE_FUNCTION_GET_CONTROLLER_INFO;
+    uint32_t ebx = 0;
+    uint32_t ecx = 0;
+    uint32_t edx = 0;
+
+    if (vesa_bios_call(VBE_FUNCTION_GET_CONTROLLER_INFO, &eax, &ebx, &ecx, &edx)) {
+        // Copy controller information into the provided struct
+        uint32_t base = (uint32_t)info;
+        __asm__ __volatile__(
+            "movw %%bx, %%es:%%di\n"
+            : 
+            : "b" (base)
+            : "%es", "%di", "memory"
+        );
+        return true;
+    }
+    return false;
+}
+
+// Return pointer to the VESA framebuffer
+void* vesa_get_framebuffer(void) {
+    vbe_mode_info_t mode_info;
+    if (vesa_get_mode_info(0x101, &mode_info)) {
+        return (void*)mode_info.PhysBasePtr;
+    }
+    return NULL;
+}
+
+// Clear the screen with a color
+void vesa_clear_screen(uint32_t color) {
+    uint32_t* framebuffer = (uint32_t*)vesa_get_framebuffer();
+    if (framebuffer) {
+        for (int y = 0; y < 480; y++) { // For 640x480 mode
+            for (int x = 0; x < 640; x++) {
+                framebuffer[y * 640 + x] = color;
+            }
+        }
+    }
+}

kernel/vesa.h

@@ -0,0 +1,67 @@
+#ifndef VESA_H
+#define VESA_H
+
+#include <stdint.h>
+#include <stdbool.h>
+
+// VESA BIOS Extension 2.0 Function Calls
+#define VBE_FUNCTION_SET_MODE        0x4F02
+#define VBE_FUNCTION_GET_MODE_INFO   0x4F01
+#define VBE_FUNCTION_GET_CONTROLLER_INFO 0x4F00
+#define VBE_FUNCTION_SET_DISPLAY_START 0x4F05
+
+// VESA Mode Information Structure (VBE 2.0)
+typedef struct {
+    uint16_t ModeAttributes;      // Mode attributes
+    uint8_t WinAAttributes;       // Window A attributes
+    uint8_t WinBAttributes;       // Window B attributes
+    uint16_t WinGranularity;      // Window granularity
+    uint16_t WinSize;             // Window size
+    uint16_t WinASegment;         // Window A segment address
+    uint16_t WinBSegment;         // Window B segment address
+    uint32_t WinFuncPtr;          // Function pointer for window
+    uint16_t BytesPerScanLine;    // Bytes per scanline
+    uint16_t XResolution;         // Horizontal resolution in pixels
+    uint16_t YResolution;         // Vertical resolution in pixels
+    uint8_t XCharSize;            // Character cell width
+    uint8_t YCharSize;            // Character cell height
+    uint8_t NumberOfPlanes;       // Number of memory planes
+    uint8_t BitsPerPixel;         // Bits per pixel
+    uint8_t NumberOfBanks;        // Number of banks
+    uint8_t MemoryModel;          // Memory model type
+    uint8_t BankSize;             // Bank size in kB
+    uint8_t NumberOfImagePages;   // Number of image pages
+    uint8_t Reserved0;            // Reserved
+    uint8_t RedMaskSize;          // Red mask size
+    uint8_t RedFieldPosition;     // Red field position
+    uint8_t GreenMaskSize;        // Green mask size
+    uint8_t GreenFieldPosition;   // Green field position
+    uint8_t BlueMaskSize;         // Blue mask size
+    uint8_t BlueFieldPosition;    // Blue field position
+    uint8_t RsvdMaskSize;         // Reserved mask size
+    uint8_t RsvdFieldPosition;    // Reserved field position
+    uint8_t DirectColorModeInfo;  // Direct color mode info
+    uint32_t PhysBasePtr;         // Physical base address of the linear framebuffer
+    uint32_t OffScreenMemOff;     // Offset to off-screen memory
+    uint16_t OffScreenMemSize;    // Size of off-screen memory
+    uint8_t Reserved1[206];       // Reserved
+} __attribute__((packed)) vbe_mode_info_t;
+
+// VESA Controller Information
+typedef struct {
+    uint8_t VESAVersion[2];       // VESA version
+    uint32_t OEMStringPtr;        // Pointer to OEM string
+    uint8_t Capabilities[4];      // Capabilities of the controller
+    uint32_t VideoModePtr;        // Pointer to supported video modes
+    uint16_t TotalMemory;         // Total video memory (in 64KB)
+    uint8_t Reserved[4];          // Reserved
+} __attribute__((packed)) vbe_controller_info_t;
+
+// Function Prototypes
+bool vesa_set_mode(uint16_t mode);
+bool vesa_get_mode_info(uint16_t mode, vbe_mode_info_t* info);
+bool vesa_get_controller_info(vbe_controller_info_t* info);
+void* vesa_get_framebuffer(void);
+void vesa_clear_screen(uint32_t color);
+
+#endif // VESA_H