asterinas/framework/aster-frame/src/arch/x86/timer/apic.rs

125 lines
4.0 KiB
Rust

// SPDX-License-Identifier: MPL-2.0
use alloc::sync::Arc;
use core::{
arch::x86_64::_rdtsc,
sync::atomic::{AtomicBool, AtomicU64, Ordering},
};
use log::info;
use spin::Once;
use trapframe::TrapFrame;
use x86::{
cpuid::cpuid,
msr::{wrmsr, IA32_TSC_DEADLINE},
};
use super::TIMER_FREQ;
use crate::{
arch::{
kernel::tsc::init_tsc_freq,
timer::pit::OperatingMode,
x86::kernel::{
apic::{DivideConfig, APIC_INSTANCE},
tsc::TSC_FREQ,
},
},
trap::IrqLine,
};
pub fn init() {
init_tsc_freq();
if is_tsc_deadline_mode_supported() {
info!("[Timer]: Enable APIC TSC deadline mode.");
init_tsc_mode();
} else {
info!("[Timer]: Enable APIC periodic mode.");
init_periodic_mode();
}
}
pub(super) static APIC_TIMER_CALLBACK: Once<Arc<dyn Fn() + Sync + Send>> = Once::new();
/// Determine if the current system supports tsc_deadline mode APIC timer
fn is_tsc_deadline_mode_supported() -> bool {
const TSC_DEADLINE_MODE_SUPPORT: u32 = 1 << 24;
let cpuid = cpuid!(1);
(cpuid.ecx & TSC_DEADLINE_MODE_SUPPORT) > 0
}
fn init_tsc_mode() {
let mut apic_lock = APIC_INSTANCE.get().unwrap().lock();
// Enable tsc deadline mode
apic_lock.set_lvt_timer(super::TIMER_IRQ_NUM.load(Ordering::Relaxed) as u64 | (1 << 18));
drop(apic_lock);
let tsc_step = TSC_FREQ.load(Ordering::Relaxed) / TIMER_FREQ;
let callback = move || unsafe {
let tsc_value = _rdtsc();
let next_tsc_value = tsc_step + tsc_value;
wrmsr(IA32_TSC_DEADLINE, next_tsc_value);
};
callback.call(());
APIC_TIMER_CALLBACK.call_once(|| Arc::new(callback));
}
fn init_periodic_mode() {
// Allocate IRQ
let mut irq = IrqLine::alloc_specific(super::TIMER_IRQ_NUM.load(Ordering::Relaxed)).unwrap();
irq.on_active(pit_callback);
// Enable PIT
super::pit::init(OperatingMode::RateGenerator);
super::pit::enable_ioapic_line(irq.clone());
// Set APIC timer count
let mut apic_lock = APIC_INSTANCE.get().unwrap().lock();
apic_lock.set_timer_div_config(DivideConfig::Divide64);
apic_lock.set_timer_init_count(0xFFFF_FFFF);
drop(apic_lock);
static IS_FINISH: AtomicBool = AtomicBool::new(false);
x86_64::instructions::interrupts::enable();
while !IS_FINISH.load(Ordering::Acquire) {
x86_64::instructions::hlt();
}
x86_64::instructions::interrupts::disable();
drop(irq);
fn pit_callback(trap_frame: &TrapFrame) {
static IN_TIME: AtomicU64 = AtomicU64::new(0);
static APIC_FIRST_COUNT: AtomicU64 = AtomicU64::new(0);
// Set a certain times of callbacks to calculate the frequency
const CALLBACK_TIMES: u64 = TIMER_FREQ / 10;
if IN_TIME.load(Ordering::Relaxed) < CALLBACK_TIMES || IS_FINISH.load(Ordering::Acquire) {
if IN_TIME.load(Ordering::Relaxed) == 0 {
let apic_lock = APIC_INSTANCE.get().unwrap().lock();
let remain_ticks = apic_lock.timer_current_count();
APIC_FIRST_COUNT.store(0xFFFF_FFFF - remain_ticks, Ordering::Relaxed);
}
IN_TIME.fetch_add(1, Ordering::Relaxed);
return;
}
// Stop PIT and APIC Timer
super::pit::disable_ioapic_line();
let mut apic_lock = APIC_INSTANCE.get().unwrap().lock();
let remain_ticks = apic_lock.timer_current_count();
apic_lock.set_timer_init_count(0);
// Init APIC Timer
let ticks = (0xFFFF_FFFF - remain_ticks - APIC_FIRST_COUNT.load(Ordering::Relaxed))
/ CALLBACK_TIMES;
apic_lock.set_timer_init_count(ticks);
apic_lock.set_lvt_timer(super::TIMER_IRQ_NUM.load(Ordering::Relaxed) as u64 | (1 << 17));
apic_lock.set_timer_div_config(DivideConfig::Divide64);
info!(
"APIC Timer ticks count:{:x}, remain ticks: {:x},Timer Freq:{} Hz",
ticks, remain_ticks, TIMER_FREQ
);
IS_FINISH.store(true, Ordering::Release);
}
}