Robert Allan JamesandClaude Sonnet 5
88eb73cfe8
Punch list §25 item 4.3.5 complete. New ioapic.c/i8042.c drivers (MADT-derived I/O APIC base, no hardcoded constants) plus a KBD-SCAN/KBD-DEBUG diagnostic word pair. Three real bugs found and fixed en route, all blocking this item's own acceptance: a fatal LAPIC spurious-vector crash (nothing had driven a real external interrupt through the I/O APIC before), OVMF leaving the keyboard device itself scanning-disabled (0xF4 fix), and isr.S's stub table only having individually-numbered stubs through vector 32 -- everything above that, including our IRQ1 vector 33, silently reported as vector 255 regardless of which IDT slot actually fired. Verified live via QEMU sendkey against KBD-SCAN: correct XT Set-1 make/break codes for two different keys. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
82 lines
2.9 KiB
C
82 lines
2.9 KiB
C
/*
|
||
StarForth — Steady-State Virtual Machine Runtime
|
||
|
||
Copyright (c) 2023–2025 Robert A. James
|
||
All rights reserved.
|
||
|
||
This file is part of the StarForth project.
|
||
|
||
Licensed under the StarForth License, Version 1.0 (the "License");
|
||
you may not use this file except in compliance with the License.
|
||
|
||
You may obtain a copy of the License at:
|
||
https://github.com/star.4th@proton.me/StarForth/LICENSE.txt
|
||
|
||
This software is provided "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
||
express or implied, including but not limited to the warranties of
|
||
merchantability, fitness for a particular purpose, and noninfringement.
|
||
|
||
See the License for the specific language governing permissions and
|
||
limitations under the License.
|
||
|
||
*/
|
||
|
||
/**
|
||
* i8042.h - PS/2 keyboard controller interface (amd64 only)
|
||
*
|
||
* Item 4.3.5 (FABRIC.md §27.5). Interrupt-driven only — no polling of the
|
||
* status port (0x64) anywhere in this path. Groundwork only: this captures
|
||
* and prints raw scancodes. Scancode-to-keycode translation and a consumer
|
||
* API belong to the REPL keyboard-input work noted in FABRIC.md, not here.
|
||
*/
|
||
|
||
#ifndef STARKERNEL_I8042_H
|
||
#define STARKERNEL_I8042_H
|
||
|
||
#include <stdint.h>
|
||
|
||
/* IDT vector the I/O APIC delivers legacy IRQ1 to. */
|
||
#define I8042_KEYBOARD_VECTOR 0x21
|
||
|
||
/**
|
||
* Enable IRQ1 delivery in the i8042 controller's command byte. Assumes the
|
||
* controller was already brought up by firmware (OVMF) — does not run the
|
||
* 0xAA self-test or the full two-port init sequence, since that is more
|
||
* than this item's scope requires.
|
||
*/
|
||
void i8042_init(void);
|
||
|
||
/**
|
||
* Drain any byte sitting in the output buffer right before unmasking IRQ1.
|
||
* Edge-triggered lines only assert on a rising edge; if OBF is already set
|
||
* (from real wall-clock time elapsing between i8042_init() and unmask
|
||
* while OBF was already high), there is no edge left to fire on, ever.
|
||
*/
|
||
void i8042_drain_stale(void);
|
||
|
||
/* Count of real keyboard IRQs serviced since boot (diagnostic). */
|
||
extern volatile uint32_t g_i8042_isr_count;
|
||
|
||
/**
|
||
* Called from the keyboard IRQ dispatch path (interrupts.c) on every
|
||
* I8042_KEYBOARD_VECTOR interrupt. Trivial by design: reads the scancode
|
||
* from port 0x60 (must always be read, or the controller never clears
|
||
* OBF and stops delivering further interrupts) and pushes it onto a small
|
||
* ring buffer. No printing, no translation, no other work — that all
|
||
* happens outside interrupt context via i8042_pop_scancode(). Does not
|
||
* issue apic_eoi() — the caller does.
|
||
*/
|
||
void i8042_handle_irq(void);
|
||
|
||
/**
|
||
* Pop one raw scancode off the ring buffer, from non-interrupt context.
|
||
* Single producer (the ISR), single reader (this function) — same shape
|
||
* already established safe on one hart elsewhere in this tree (§21.1).
|
||
*
|
||
* @param out Written with the popped scancode on success.
|
||
* @return 1 if a scancode was popped, 0 if the buffer was empty.
|
||
*/
|
||
int i8042_pop_scancode(uint8_t *out);
|
||
|
||
#endif /* STARKERNEL_I8042_H */
|