Development

[assembler-0]

Summary by CodeRabbit

• Bug Fixes

  • Corrected paging initialization to properly load the page directory base address during system startup.

• New Features

  • Introduced a new splash screen with enhanced visual presentation during system boot.

• Chores

  • Updated the timer frequency constant to 200 Hz, increasing the system timer rate.

[coderabbitai]

Caution

Review failed

The pull request is closed.

Walkthrough

This update modifies two core components: it doubles the value of the PIT_FREQUENCY_HZ constant in the timer driver header, and it corrects the operand order in the EnablePagingAndJump assembly routine to properly set the CR3 register for paging. Additionally, it replaces the kernel's ASCII splash screen with a new splash screen implementation that uses direct VGA text mode manipulation, adding new source and header files and updating the build configuration accordingly. No public interfaces or signatures were changed except for adding the ShowSplashScreen() declaration.

Changes

File(s)	Change Summary
drivers/Pic.h	Updated PIT_FREQUENCY_HZ macro value from 100 to 200.
kernel/memory/AsmHelpers.asm	Fixed EnablePagingAndJump to write value from RDI into CR3, ensuring correct paging behavior.
kernel/core/Kernel.c	Removed local AsciiSplash function; replaced call with ShowSplashScreen() and included Splash.h.
kernel/etc/Splash.c, kernel/etc/Splash.h	Added new splash screen implementation with functions to draw a box, print strings, and show splash screen.
meson.build	Added kernel/etc directory and Splash.c to build configuration.

Sequence Diagram(s)

sequenceDiagram
    participant Kernel
    participant AsmHelpers.asm

    Kernel->>AsmHelpers.asm: Call EnablePagingAndJump(newCR3, jumpAddr)
    AsmHelpers.asm->>AsmHelpers.asm: mov cr3, rdi (set CR3)
    AsmHelpers.asm->>AsmHelpers.asm: jmp rsi (jump to address)

Loading

sequenceDiagram
    participant KernelMain
    participant Splash

    KernelMain->>Splash: ShowSplashScreen()
    Splash->>Splash: Clear screen
    Splash->>Splash: DrawBox()
    Splash->>Splash: PrintString() x3 (centered lines)
    Splash->>Splash: Busy-wait delay
    Splash-->>KernelMain: Return after splash display

Loading

Possibly related PRs

• Development #40: Introduced the initial version and declaration of the EnablePagingAndJump assembly routine, which is directly modified in this PR.
• Development #26: Modified PIT_FREQUENCY_HZ macro in drivers/Pic.h and added function prototypes, related to timer configuration changes.

Poem

The timer ticks now twice as fast,
And paging’s set just right at last.
With CR3 now properly in place,
The kernel leaps with nimble grace.
A splash of text, a box so neat,
New screens to greet — a coder’s treat!
🐇✨
Code hops ahead, no time to waste—
Onward, VoidFrame, make your haste!

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📜 Recent review details

Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 0e57492 and 2e35cc7.

📒 Files selected for processing (4)

• kernel/core/Kernel.c (3 hunks)
• kernel/etc/Splash.c (1 hunks)
• kernel/etc/Splash.h (1 hunks)
• meson.build (2 hunks)

✨ Finishing Touches

• 📝 Generate Docstrings

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