Files
MontaukOS/kernel/src/ACPI/AcpiEvents.cpp
T

148 lines
5.6 KiB
C++

/*
* AcpiEvents.cpp
* ACPI fixed event handling (SCI interrupt, power button, etc.)
* Copyright (c) 2026 Daniel Hammer
*/
#include "AcpiEvents.hpp"
#include <ACPI/AcpiSleep.hpp>
#include <Io/IoPort.hpp>
#include <Hal/Apic/Apic.hpp>
#include <Hal/Apic/IoApic.hpp>
#include <Hal/Apic/Interrupts.hpp>
#include <Terminal/Terminal.hpp>
#include <CppLib/Stream.hpp>
using namespace Kt;
namespace Hal {
namespace AcpiEvents {
// ============================================================================
// State
// ============================================================================
static uint32_t g_pm1aEventBlock = 0;
static uint32_t g_pm1bEventBlock = 0;
static uint8_t g_pm1EventLength = 0;
static uint16_t g_sciIrq = 0;
static bool g_initialized = false;
// ============================================================================
// PM1 register helpers
// ============================================================================
static uint16_t ReadPM1Status() {
uint16_t sts = 0;
if (g_pm1aEventBlock != 0)
sts |= Io::In16((uint16_t)g_pm1aEventBlock);
if (g_pm1bEventBlock != 0)
sts |= Io::In16((uint16_t)g_pm1bEventBlock);
return sts;
}
static void ClearPM1StatusBits(uint16_t bits) {
// Write-1-to-clear semantics
if (g_pm1aEventBlock != 0)
Io::Out16(bits, (uint16_t)g_pm1aEventBlock);
if (g_pm1bEventBlock != 0)
Io::Out16(bits, (uint16_t)g_pm1bEventBlock);
}
static void EnablePM1Events(uint16_t mask) {
uint16_t enableOffset = g_pm1EventLength / 2;
if (enableOffset == 0) return;
if (g_pm1aEventBlock != 0) {
uint16_t en = Io::In16((uint16_t)(g_pm1aEventBlock + enableOffset));
en |= mask;
Io::Out16(en, (uint16_t)(g_pm1aEventBlock + enableOffset));
}
if (g_pm1bEventBlock != 0) {
uint16_t en = Io::In16((uint16_t)(g_pm1bEventBlock + enableOffset));
en |= mask;
Io::Out16(en, (uint16_t)(g_pm1bEventBlock + enableOffset));
}
}
// ============================================================================
// SCI Interrupt Handler
// ============================================================================
static void SciHandler(uint8_t irq) {
uint16_t sts = ReadPM1Status();
if (sts & AcpiSleep::PM1_PWRBTN_STS) {
ClearPM1StatusBits(AcpiSleep::PM1_PWRBTN_STS);
KernelLogStream(INFO, "ACPI") << "Power button pressed";
}
if (sts & AcpiSleep::PM1_SLPBTN_STS) {
ClearPM1StatusBits(AcpiSleep::PM1_SLPBTN_STS);
KernelLogStream(INFO, "ACPI") << "Sleep button pressed";
}
// Note: EOI is sent by HalIrqDispatch after this handler returns.
}
// ============================================================================
// Initialize
// ============================================================================
void Initialize(ACPI::CommonSDTHeader* xsdt) {
FADT::ParsedFADT fadt{};
if (!FADT::Parse(xsdt, fadt) || !fadt.Valid) {
KernelLogStream(ERROR, "ACPI") << "Failed to parse FADT - ACPI events unavailable";
return;
}
g_pm1aEventBlock = fadt.PM1aEventBlock;
g_pm1bEventBlock = fadt.PM1bEventBlock;
g_pm1EventLength = fadt.PM1EventLength;
g_sciIrq = fadt.SCI_Interrupt;
if (g_pm1aEventBlock == 0) {
KernelLogStream(ERROR, "ACPI") << "No PM1a event block - ACPI events unavailable";
return;
}
// Clear any pending status bits
ClearPM1StatusBits(
AcpiSleep::PM1_PWRBTN_STS | AcpiSleep::PM1_SLPBTN_STS |
AcpiSleep::PM1_WAK_STS | AcpiSleep::PM1_TMR_STS |
AcpiSleep::PM1_GBL_STS | AcpiSleep::PM1_RTC_STS |
AcpiSleep::PM1_BM_STS);
// Enable power button event
EnablePM1Events(AcpiSleep::PM1_PWRBTN_EN);
// Route SCI to an IRQ vector. The SCI is level-triggered,
// active-low (ACPI spec requirement). The MADT may have an
// Interrupt Source Override for this IRQ that already sets
// these flags; RouteIrq applies overrides automatically.
uint8_t sciVector = IRQ_VECTOR_BASE + (uint8_t)g_sciIrq;
uint8_t bspApicId = (uint8_t)LocalApic::GetId();
// Register the handler before routing to avoid missing events
RegisterIrqHandler((uint8_t)g_sciIrq, SciHandler);
// Route via IoApic (applies MADT overrides for polarity/trigger)
IoApic::RouteIrq((uint8_t)g_sciIrq, sciVector, bspApicId);
g_initialized = true;
KernelLogStream(OK, "ACPI") << "ACPI events initialized (SCI IRQ "
<< base::dec << (uint64_t)g_sciIrq << ", vector "
<< (uint64_t)sciVector << ")";
}
void Reinitialize() {
if (!g_initialized) return;
// Clear pending status and re-enable power button event
ClearPM1StatusBits(
AcpiSleep::PM1_PWRBTN_STS | AcpiSleep::PM1_SLPBTN_STS);
EnablePM1Events(AcpiSleep::PM1_PWRBTN_EN);
}
};
};