Development #88
Development #88
Conversation
WalkthroughRefactors boot sequence: replaces SystemInitS1/S2 with PXS1/PXS2, relocates identity-mapping and paging enablement into PXS1, moves higher-half initialization into PXS2, adds memory layout validation and bootstrap summary helpers, updates KernelMain and KernelMainHigherHalf flows, and introduces additional bootstrap diagnostics and progress output. Changes
Sequence Diagram(s)sequenceDiagram
participant MB as Multiboot Loader
participant KM as KernelMain
participant P1 as PXS1
participant MMU as Paging/MMU
participant HH as Higher-Half Entry
participant KHH as KernelMainHigherHalf
participant P2 as PXS2
participant SUB as Subsystems
MB->>KM: Pass Multiboot info
KM->>P1: PXS1(info)
P1->>P1: Init serial/VBE/console, parse Multiboot
P1->>MMU: Identity map, map kernel+stack (log progress/diagnostics)
P1->>MMU: Enable paging
P1->>HH: Jump to higher-half entry
HH->>KHH: Transfer control
KHH->>P2: PXS2()
P2->>P2: CPU feature checks, ValidateMemoryLayout, PrintBootstrapSummary
P2->>SUB: Init VMM, heap, GDT/IDT/PIC/PIT/ISA/PCI, drivers, FS
P2->>SUB: Enable protections, unmask IRQs
Estimated code review effort🎯 4 (Complex) | ⏱️ ~45 minutes Possibly related PRs
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Actionable comments posted: 1
🔭 Outside diff range comments (1)
kernel/core/Kernel.c (1)
424-500: Align identity-map allocation attempt limitsrg shows three allocation loops with inconsistent attempt limits (two use 32, one uses 64). Make them use a single configurable constant to avoid surprising failures.
Files/locations to update:
- kernel/memory/VMem.c:78 — for (int attempt = 0; attempt < 32; attempt++) {
- kernel/core/Kernel.c:73 — for (int attempt = 0; attempt < 32; attempt++) {
- kernel/core/Kernel.c:459 — for (int attempt = 0; attempt < 64; attempt++) {
Suggested minimal change (define a single constant and use it in all loops — pick 64 to preserve the least-restrictive current behavior):
+#define MAX_IDENTITY_MAP_ALLOC_ATTEMPTS 64Replace each loop bound:
- for (int attempt = 0; attempt < 32; attempt++) { + for (int attempt = 0; attempt < MAX_IDENTITY_MAP_ALLOC_ATTEMPTS; attempt++) {and
- for (int attempt = 0; attempt < 64; attempt++) { + for (int attempt = 0; attempt < MAX_IDENTITY_MAP_ALLOC_ATTEMPTS; attempt++) {Notes: put the #define in a shared header (e.g., a common kernel config/header) so both kernel/core/Kernel.c and kernel/memory/VMem.c include the same value. Consider making this configurable or documented so boot-time allocation behavior is explicit.
🧹 Nitpick comments (2)
kernel/core/Kernel.c (2)
429-429: Fix logical operator spacing.Missing space between
&&andSerialInitPort(COM4).- if (SerialInitPort(COM2) != 0 && SerialInitPort(COM3) != 0 &&SerialInitPort(COM4) != 0) { + if (SerialInitPort(COM2) != 0 && SerialInitPort(COM3) != 0 && SerialInitPort(COM4) != 0) {
155-166: Consider making progress reporting configurable.The bootstrap progress reporting is helpful but could be made more flexible with configurable thresholds.
+#define BOOTSTRAP_PROGRESS_MB_INTERVAL 256 // Show MB count every 256MB +#define BOOTSTRAP_PROGRESS_DOT_INTERVAL 64 // Show dot every 64MB + static uint64_t pages_mapped = 0; pages_mapped++; - // Show progress every 64K pages (256MB) - if (pages_mapped % 65536 == 0) { + // Show progress every BOOTSTRAP_PROGRESS_MB_INTERVAL + if (pages_mapped % (BOOTSTRAP_PROGRESS_MB_INTERVAL * 256) == 0) { PrintKernelInt((pages_mapped * PAGE_SIZE) / (1024 * 1024)); PrintKernel("MB "); } - // Show dots every 16K pages (64MB) for finer progress - else if (pages_mapped % 16384 == 0) { + // Show dots every BOOTSTRAP_PROGRESS_DOT_INTERVAL for finer progress + else if (pages_mapped % (BOOTSTRAP_PROGRESS_DOT_INTERVAL * 256) == 0) { PrintKernel("."); }
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📒 Files selected for processing (1)
kernel/core/Kernel.c(6 hunks)
🧰 Additional context used
🧠 Learnings (2)
📚 Learning: 2025-08-10T06:03:22.076Z
Learnt from: assembler-0
PR: assembler-0/VoidFrame#62
File: kernel/core/Panic.c:69-79
Timestamp: 2025-08-10T06:03:22.076Z
Learning: In VoidFrame kernel, after VBEShowPanic() draws a panic image to the framebuffer, continuing to use text console operations like PrintKernelAt() causes display corruption because it tries to render text on top of the raw pixel data. The panic handler must choose either pure VBE graphics mode (show image only) or pure text console mode, but not mix both.
Applied to files:
kernel/core/Kernel.c
📚 Learning: 2025-08-10T06:03:22.076Z
Learnt from: assembler-0
PR: assembler-0/VoidFrame#62
File: kernel/core/Panic.c:69-79
Timestamp: 2025-08-10T06:03:22.076Z
Learning: In VoidFrame kernel, mixing VBE graphics mode operations (like VBEShowPanic drawing to framebuffer) with text console operations causes display corruption with random pixels. The panic handler must choose either pure VBE graphics mode or pure text mode, not both simultaneously.
Applied to files:
kernel/core/Kernel.c
🧬 Code Graph Analysis (1)
kernel/core/Kernel.c (2)
kernel/memory/Memory.c (3)
IsPageFree(59-65)AllocPage(178-234)FreePage(276-314)kernel/memory/MemOps.c (1)
FastZeroPage(133-147)
🔇 Additional comments (4)
kernel/core/Kernel.c (4)
356-391: LGTM! Well-structured memory layout validation.The new
ValidateMemoryLayoutfunction provides comprehensive validation of kernel memory boundaries with proper checks for stack overlap, multiboot info location, and virtual address space boundaries. The warning messages are clear and will help debug potential issues.
393-420: LGTM! Useful bootstrap summary for diagnostics.The
PrintBootstrapSummaryfunction provides valuable insights into page table allocation and identity mapping details. This will be helpful for debugging bootstrap issues.
139-151: Good addition of remapping diagnostics.The new remapping check in
BootstrapMapPageis valuable for debugging page table issues. The warning clearly indicates when a virtual address is being remapped to a different physical address.
514-657: Comprehensive PXS2 initialization with improved diagnostics.The new PXS2 function provides excellent organization of the pre-execution sequence with detailed progress reporting and memory statistics. The addition of memory pool initialization early in the sequence is a good optimization for small allocations.
| if ((stack_start >= kernel_start && stack_start < kernel_end) || | ||
| (stack_end > kernel_start && stack_end <= kernel_end)) { | ||
| PrintKernelWarning("[WARNING] Stack overlaps with kernel code\n"); | ||
| } |
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Misplaced closing brace.
The closing brace is incorrectly indented and appears to be misplaced outside the if statement block.
if ((stack_start >= kernel_start && stack_start < kernel_end) ||
(stack_end > kernel_start && stack_end <= kernel_end)) {
PrintKernelWarning("[WARNING] Stack overlaps with kernel code\n");
- }
+ }📝 Committable suggestion
‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
| } | |
| } |
🤖 Prompt for AI Agents
In kernel/core/Kernel.c around line 378, the closing brace is
misplaced/incorrectly indented and has been moved outside the intended
if-statement block; move the brace so it closes the correct if block (adjust
indentation to match surrounding code) ensuring the conditional block's start
and end braces align, and recompile to verify no scope or syntax errors remain.
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oh thanks thats a copy issue, also about the shell, is there a way we can make it more advanced? like can scroll to past commands? just a simple one, by arrow keys or mouse id fine
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🧩 Analysis chain
@assembler-0 Great question! Let me examine the current shell implementation to see what we're working with and suggest how to add command history functionality.
Based on my examination of the codebase, here's how you can enhance the shell with command history:
Current State
The kernel has basic PS2 keyboard support and a shell system, but it appears to be a simple implementation without command history.
Implementing Command History
Here's what you'll need to add:
1. Command History Buffer
Add to your shell structure:
#define MAX_HISTORY 50
#define MAX_CMD_LEN 256
typedef struct {
char commands[MAX_HISTORY][MAX_CMD_LEN];
int count;
int current_index;
int history_index;
} CommandHistory;2. Arrow Key Detection
Enhance your keyboard handler to detect arrow keys:
// In your keyboard interrupt handler
switch (scancode) {
case 0x48: // Up arrow
shell_history_prev();
break;
case 0x50: // Down arrow
shell_history_next();
break;
case 0x4B: // Left arrow
shell_cursor_left();
break;
case 0x4D: // Right arrow
shell_cursor_right();
break;
}3. History Navigation Functions
void shell_history_prev(void) {
if (history.count > 0 && history.history_index > 0) {
history.history_index--;
// Clear current line and display historical command
shell_clear_line();
shell_display_command(history.commands[history.history_index]);
}
}
void shell_history_next(void) {
if (history.history_index < history.count - 1) {
history.history_index++;
shell_clear_line();
shell_display_command(history.commands[history.history_index]);
} else {
// Show empty line if at end of history
shell_clear_line();
}
}4. Command Storage
When a command is executed:
void shell_add_to_history(const char* command) {
if (strlen(command) == 0) return;
// Shift existing commands if buffer is full
if (history.count >= MAX_HISTORY) {
for (int i = 0; i < MAX_HISTORY - 1; i++) {
strcpy(history.commands[i], history.commands[i + 1]);
}
history.count = MAX_HISTORY - 1;
}
// Add new command
strcpy(history.commands[history.count], command);
history.count++;
history.history_index = history.count;
}Implementation Tips
- Start Simple: Begin with just Up/Down arrow support for command history
- Buffer Management: Use a circular buffer to efficiently manage memory
- Cursor Position: Track cursor position for left/right arrow editing
- Key Combinations: Consider Ctrl+R for reverse search later
The mouse support would be more complex since you'd need to implement mouse driver integration, but arrow keys are definitely achievable with your current PS2 setup!
Would you like me to help you implement any specific part of this, or examine the existing keyboard handling code more closely?
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rg -n "shell\|command\|prompt" --type c --type h -A3 -B1
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Perfect! Now I can see the actual implementation. The shell is quite basic and there's definitely room for command history enhancement. Let me provide you with a concrete implementation plan:
Current Shell Analysis
Your current shell (kernel/etc/Shell.c) is very minimal with just basic command parsing. The PS2 driver handles keyboard input with scan code processing.
Enhanced Shell with Command History
Here's exactly what you need to add:
1. Update Shell.h
Add these to your kernel/etc/Shell.h:
#define MAX_HISTORY_ENTRIES 50
#define MAX_COMMAND_LENGTH 256
typedef struct {
char commands[MAX_HISTORY_ENTRIES][MAX_COMMAND_LENGTH];
int total_commands;
int current_position;
int browse_position;
char current_input[MAX_COMMAND_LENGTH];
int input_length;
int cursor_position;
} ShellHistory;
extern ShellHistory shell_history;
// New function declarations
void shell_add_to_history(const char* command);
void shell_history_up(void);
void shell_history_down(void);
void shell_clear_current_line(void);
void shell_redraw_prompt_and_input(void);2. Enhance Shell.c
Add this to your kernel/etc/Shell.c:
ShellHistory shell_history = {0};
void ShellInit(void) {
cmd_pos = 0;
shell_history.total_commands = 0;
shell_history.current_position = 0;
shell_history.browse_position = 0;
shell_history.input_length = 0;
shell_history.cursor_position = 0;
}
void shell_add_to_history(const char* command) {
if (!command || strlen(command) == 0) return;
// Don't add duplicate of last command
if (shell_history.total_commands > 0 &&
strcmp(shell_history.commands[shell_history.total_commands - 1], command) == 0) {
return;
}
// If history is full, shift everything up
if (shell_history.total_commands >= MAX_HISTORY_ENTRIES) {
for (int i = 0; i < MAX_HISTORY_ENTRIES - 1; i++) {
strcpy(shell_history.commands[i], shell_history.commands[i + 1]);
}
shell_history.total_commands = MAX_HISTORY_ENTRIES - 1;
}
// Add new command
strcpy(shell_history.commands[shell_history.total_commands], command);
shell_history.total_commands++;
shell_history.browse_position = shell_history.total_commands;
}
void shell_clear_current_line(void) {
// Move cursor to beginning of line and clear it
PrintKernel("\r");
for (int i = 0; i < 80; i++) PrintKernel(" ");
PrintKernel("\r");
}
void shell_redraw_prompt_and_input(void) {
shell_clear_current_line();
PrintKernel("VoidFrame> ");
PrintKernel(shell_history.current_input);
}
void shell_history_up(void) {
if (shell_history.total_commands == 0) return;
if (shell_history.browse_position > 0) {
shell_history.browse_position--;
strcpy(shell_history.current_input,
shell_history.commands[shell_history.browse_position]);
shell_history.input_length = strlen(shell_history.current_input);
shell_history.cursor_position = shell_history.input_length;
shell_redraw_prompt_and_input();
}
}
void shell_history_down(void) {
if (shell_history.total_commands == 0) return;
if (shell_history.browse_position < shell_history.total_commands - 1) {
shell_history.browse_position++;
strcpy(shell_history.current_input,
shell_history.commands[shell_history.browse_position]);
shell_history.input_length = strlen(shell_history.current_input);
shell_history.cursor_position = shell_history.input_length;
shell_redraw_prompt_and_input();
} else if (shell_history.browse_position == shell_history.total_commands - 1) {
// Go to empty line
shell_history.browse_position = shell_history.total_commands;
shell_history.current_input[0] = '\0';
shell_history.input_length = 0;
shell_history.cursor_position = 0;
shell_redraw_prompt_and_input();
}
}3. Modify PS2 Keyboard Handler
In your drivers/PS2.c, enhance the keyboard interrupt handler to detect arrow keys:
// In your keyboard interrupt handler function, add these cases:
switch (scancode) {
case 0x48: // Up arrow key
shell_history_up();
break;
case 0x50: // Down arrow key
shell_history_down();
break;
case 0x4B: // Left arrow (for future cursor movement)
// TODO: implement cursor left movement
break;
case 0x4D: // Right arrow (for future cursor movement)
// TODO: implement cursor right movement
break;
// Your existing key handling code...
}4. Update Command Processing
When a command is executed, make sure to add it to history:
// In your command execution function
void process_command(char* command) {
// Add to history before processing
shell_add_to_history(command);
// Reset browse position
shell_history.browse_position = shell_history.total_commands;
// Your existing command processing code...
}Key Benefits of This Approach
- Simple Implementation: Builds on your existing code structure
- Memory Efficient: Fixed-size circular buffer
- Arrow Key Support: Up/Down for history navigation
- Duplicate Prevention: Won't add identical consecutive commands
- Extensible: Easy to add left/right cursor movement later
This will give you a much more usable shell with proper command history! The implementation is kernel-appropriate and doesn't require complex memory management.
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Perfect! Now I can see exactly how your shell and keyboard system work. Here's the complete implementation to add command history with arrow key support:
1. Update Shell.h
Add this to kernel/etc/Shell.h:
#ifndef SHELL_H
#define SHELL_H
#define MAX_HISTORY_ENTRIES 50
#define MAX_COMMAND_LENGTH 256
typedef struct {
char commands[MAX_HISTORY_ENTRIES][MAX_COMMAND_LENGTH];
int total_commands;
int browse_position;
char current_input[MAX_COMMAND_LENGTH];
int input_length;
} ShellHistory;
// Special key codes for shell
#define SHELL_KEY_UP_ARROW 0x80
#define SHELL_KEY_DOWN_ARROW 0x81
#define SHELL_KEY_LEFT_ARROW 0x82
#define SHELL_KEY_RIGHT_ARROW 0x83
void ShellInit(void);
void ShellProcess(void);
void shell_add_to_history(const char* command);
void shell_history_up(void);
void shell_history_down(void);
void shell_clear_current_line(void);
void shell_redraw_prompt_and_input(void);
extern ShellHistory shell_history;
#endif2. Update PS2.c KeyboardHandler
Modify the KeyboardHandler() function in drivers/PS2.c:
void KeyboardHandler(void) {
uint8_t status = inb(KEYBOARD_STATUS_PORT);
if (!(status & 0x01)) return;
if (status & 0x20) {
return;
}
uint8_t scancode = inb(KEYBOARD_DATA_PORT);
int key_released = scancode & 0x80;
scancode &= 0x7F;
// Handle modifier keys
if (scancode == 0x2A || scancode == 0x36) { // Left/Right Shift
shift_pressed = !key_released;
return;
}
if (scancode == 0x1D) { // Ctrl
ctrl_pressed = !key_released;
return;
}
if (scancode == 0x38) { // Alt
alt_pressed = !key_released;
return;
}
if (key_released) return;
// NEW: Handle arrow keys
if (scancode == 0x48) { // Up arrow
if (buffer_count < 255) {
input_buffer[buffer_tail] = SHELL_KEY_UP_ARROW;
buffer_tail = (buffer_tail + 1) % 256;
buffer_count++;
}
return;
}
if (scancode == 0x50) { // Down arrow
if (buffer_count < 255) {
input_buffer[buffer_tail] = SHELL_KEY_DOWN_ARROW;
buffer_tail = (buffer_tail + 1) % 256;
buffer_count++;
}
return;
}
if (scancode == 0x4B) { // Left arrow
if (buffer_count < 255) {
input_buffer[buffer_tail] = SHELL_KEY_LEFT_ARROW;
buffer_tail = (buffer_tail + 1) % 256;
buffer_count++;
}
return;
}
if (scancode == 0x4D) { // Right arrow
if (buffer_count < 255) {
input_buffer[buffer_tail] = SHELL_KEY_RIGHT_ARROW;
buffer_tail = (buffer_tail + 1) % 256;
buffer_count++;
}
return;
}
if (scancode >= sizeof(scancode_to_ascii)) return;
char c;
if (shift_pressed) {
c = scancode_to_ascii_shift[scancode];
} else {
c = scancode_to_ascii[scancode];
}
// Handle Ctrl combinations
if (ctrl_pressed && c >= 'a' && c <= 'z') {
c = c - 'a' + 1;
} else if (ctrl_pressed && c >= 'A' && c <= 'Z') {
c = c - 'A' + 1;
}
if (c && buffer_count < 255) {
input_buffer[buffer_tail] = c;
buffer_tail = (buffer_tail + 1) % 256;
buffer_count++;
}
}3. Update Shell.c
Replace the entire Shell.c with this enhanced version:
// Add this at the top after existing includes
ShellHistory shell_history = {0};
// Add these new functions before ShellInit()
void shell_add_to_history(const char* command) {
if (!command || strlen(command) == 0) return;
// Don't add duplicate of last command
if (shell_history.total_commands > 0 &&
FastStrCmp(shell_history.commands[shell_history.total_commands - 1], command) == 0) {
return;
}
// If history is full, shift everything up
if (shell_history.total_commands >= MAX_HISTORY_ENTRIES) {
for (int i = 0; i < MAX_HISTORY_ENTRIES - 1; i++) {
FastMemcpy(shell_history.commands[i], shell_history.commands[i + 1], MAX_COMMAND_LENGTH);
}
shell_history.total_commands = MAX_HISTORY_ENTRIES - 1;
}
// Add new command
FastMemcpy(shell_history.commands[shell_history.total_commands], command, MAX_COMMAND_LENGTH);
shell_history.total_commands++;
shell_history.browse_position = shell_history.total_commands;
}
void shell_clear_current_line(void) {
// Move cursor to beginning of line and clear it
PrintKernel("\r");
for (int i = 0; i < 120; i++) PrintKernel(" ");
PrintKernel("\r");
}
void shell_redraw_prompt_and_input(void) {
shell_clear_current_line();
PrintKernel(current_dir);
PrintKernel("> ");
PrintKernel(shell_history.current_input);
}
void shell_history_up(void) {
if (shell_history.total_commands == 0) return;
if (shell_history.browse_position > 0) {
shell_history.browse_position--;
FastMemcpy(shell_history.current_input,
shell_history.commands[shell_history.browse_position], MAX_COMMAND_LENGTH);
shell_history.input_length = strlen(shell_history.current_input);
shell_redraw_prompt_and_input();
}
}
void shell_history_down(void) {
if (shell_history.total_commands == 0) return;
if (shell_history.browse_position < shell_history.total_commands - 1) {
shell_history.browse_position++;
FastMemcpy(shell_history.current_input,
shell_history.commands[shell_history.browse_position], MAX_COMMAND_LENGTH);
shell_history.input_length = strlen(shell_history.current_input);
shell_redraw_prompt_and_input();
} else if (shell_history.browse_position == shell_history.total_commands - 1) {
// Go to empty line
shell_history.browse_position = shell_history.total_commands;
shell_history.current_input[0] = '\0';
shell_history.input_length = 0;
shell_redraw_prompt_and_input();
}
}
// Update ShellInit()
void ShellInit(void) {
cmd_pos = 0;
shell_history.total_commands = 0;
shell_history.browse_position = 0;
shell_history.input_length = 0;
FastMemset(shell_history.current_input, 0, MAX_COMMAND_LENGTH);
}
// Replace the existing ShellProcess() function with this enhanced version:
void ShellProcess(void) {
PrintKernelSuccess("System: VoidFrame Shell v0.0.1-beta (with command history)\n");
show_help();
// Initialize current input
FastMemset(shell_history.current_input, 0, MAX_COMMAND_LENGTH);
shell_history.input_length = 0;
while (1) {
if (HasInput()) {
char c = GetChar();
// Handle special keys
if (c == SHELL_KEY_UP_ARROW) {
shell_history_up();
// Update cmd_pos to match current input
cmd_pos = shell_history.input_length;
FastMemcpy(command_buffer, shell_history.current_input, cmd_pos);
continue;
}
if (c == SHELL_KEY_DOWN_ARROW) {
shell_history_down();
// Update cmd_pos to match current input
cmd_pos = shell_history.input_length;
FastMemcpy(command_buffer, shell_history.current_input, cmd_pos);
continue;
}
if (c == '\n') {
PrintKernel("\n");
command_buffer[cmd_pos] = 0;
// Add to history before executing
if (cmd_pos > 0) {
shell_add_to_history(command_buffer);
}
ExecuteCommand(command_buffer);
cmd_pos = 0;
// Reset input state
FastMemset(shell_history.current_input, 0, MAX_COMMAND_LENGTH);
shell_history.input_length = 0;
shell_history.browse_position = shell_history.total_commands;
PrintKernel(current_dir);
PrintKernel("> ");
} else if (c == '\b') {
if (cmd_pos > 0) {
cmd_pos--;
shell_history.input_length--;
shell_history.current_input[shell_history.input_length] = '\0';
PrintKernel("\b \b");
}
} else if (cmd_pos < 255 && c >= 32 && c <= 126) { // Printable characters
command_buffer[cmd_pos++] = c;
shell_history.current_input[shell_history.input_length++] = c;
shell_history.current_input[shell_history.input_length] = '\0';
char str[2] = {c, 0};
PrintKernel(str);
}
} else {
Yield();
}
}
}Key Features Added
- Arrow Key Detection: Up/Down arrows now work for command history
- History Buffer: Stores up to 50 previous commands
- Duplicate Prevention: Won't add identical consecutive commands
- Line Redrawing: Properly clears and redraws the command line
- State Management: Keeps track of current position in history
- Integration: Works seamlessly with your existing command system
How It Works
- Up Arrow: Navigate to previous commands in history
- Down Arrow: Navigate to newer commands, or empty line at the end
- Enter: Executes command and adds it to history
- Backspace: Works normally for editing current input
The implementation is memory-efficient and integrates perfectly with your existing PS2 keyboard handling and shell architecture. Just compile and you'll have a much more usable shell!
The left/right arrows are also detected (for future cursor positioning) but not implemented yet - you can add that functionality later if needed.
🧬 Code Graph Analysis Results
-
File: kernel/etc/Shell.c, lines 691-693
- Snippet:
void ShellInit(void) {
cmd_pos = 0;
}
- Snippet:
-
File: kernel/PS2.c, lines 62-116
-
Snippet:
void PS2Init(void) {
// Flush the keyboard controller's buffer
while (inb(KEYBOARD_STATUS_PORT) & 0x01) {
inb(KEYBOARD_DATA_PORT);
}// Disable both devices first wait_for_input_buffer_empty(); outb(KEYBOARD_STATUS_PORT, 0xAD); // Disable keyboard wait_for_input_buffer_empty(); outb(KEYBOARD_STATUS_PORT, PS2_CMD_DISABLE_AUX); // Disable mouse // Read current configuration wait_for_input_buffer_empty(); outb(KEYBOARD_STATUS_PORT, PS2_CMD_READ_CONFIG); wait_for_output_buffer_full(); uint8_t config = inb(KEYBOARD_DATA_PORT); config |= 0x03; // Enable keyboard and mouse interrupts // Write back configuration wait_for_input_buffer_empty(); outb(KEYBOARD_STATUS_PORT, PS2_CMD_WRITE_CONFIG); wait_for_input_buffer_empty(); outb(KEYBOARD_DATA_PORT, config); // Enable auxiliary device wait_for_input_buffer_empty(); outb(KEYBOARD_STATUS_PORT, PS2_CMD_ENABLE_AUX); // Initialize mouse send_mouse_command(MOUSE_CMD_SET_DEFAULTS); send_mouse_command(MOUSE_CMD_ENABLE); // Re-enable keyboard wait_for_input_buffer_empty(); outb(KEYBOARD_STATUS_PORT, 0xAE); // Reset keyboard wait_for_input_buffer_empty(); outb(KEYBOARD_DATA_PORT, 0xFF); wait_for_output_buffer_full(); uint8_t response = inb(KEYBOARD_DATA_PORT); if (response == 0xFA) { wait_for_output_buffer_full(); inb(KEYBOARD_DATA_PORT); // Should be 0xAA } // Clear software state buffer_head = buffer_tail = buffer_count = 0; shift_pressed = ctrl_pressed = alt_pressed = 0; mouse.x = mouse.y = 0; mouse.packet_index = 0; mouse.buttons = 0;}
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1 participant
Summary by CodeRabbit
New Features
Refactor