arbirq.c

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/*
 * PROJECT:     ReactOS Kernel
 * LICENSE:     MIT (https://spdx.org/licenses/MIT)
 * PURPOSE:     PnP manager Root IRQ Arbiter
 * COPYRIGHT:   Copyright 2025-2026 Justin Miller <justin.miller@reactos.org>
 */
 
/* INCLUDES *****************************************************************/
 
#include <ntoskrnl.h>
#define NDEBUG
#include <debug.h>
 
/* GLOBALS *******************************************************************/
 
extern ARBITER_INSTANCE IopRootIrqArbiter;
 
/* FUNCTIONS *****************************************************************/
 
NTSTATUS
NTAPI
IopArbIrqUnpackRequirements(
    _In_ PIO_RESOURCE_DESCRIPTOR IoDescriptor,
    _Out_ PUINT64 OutMinimumAddress,
    _Out_ PUINT64 OutMaximumAddress,
    _Out_ PUINT64 OutLength,
    _Out_ PUINT64 OutAlignment)
{
    PAGED_CODE();
 
    *OutMinimumAddress = IoDescriptor->u.Interrupt.MinimumVector;
    *OutMaximumAddress = IoDescriptor->u.Interrupt.MaximumVector;
    *OutLength = 1;
    *OutAlignment = 1;
 
    return STATUS_SUCCESS;
}
 
NTSTATUS
NTAPI
IopArbIrqPackResource(
    _In_ PIO_RESOURCE_DESCRIPTOR IoDescriptor,
    _In_ UINT64 Start,
    _Out_ PCM_PARTIAL_RESOURCE_DESCRIPTOR CmDescriptor)
{
    PAGED_CODE();
 
    CmDescriptor->Type = CmResourceTypeInterrupt;
    CmDescriptor->ShareDisposition = IoDescriptor->ShareDisposition;
    CmDescriptor->Flags = IoDescriptor->Flags;
 
    CmDescriptor->u.Interrupt.Level = (ULONG)Start;
    CmDescriptor->u.Interrupt.Vector = (ULONG)Start;
    CmDescriptor->u.Interrupt.Affinity = (KAFFINITY)-1;
 
    return STATUS_SUCCESS;
}
 
NTSTATUS
NTAPI
IopArbIrqUnpackResource(
    _In_ PCM_PARTIAL_RESOURCE_DESCRIPTOR CmDescriptor,
    _Out_ PUINT64 Start,
    _Out_ PUINT64 OutLength)
{
    PAGED_CODE();
 
    *Start = CmDescriptor->u.Interrupt.Vector;
    *OutLength = 1;
 
    return STATUS_SUCCESS;
}
 
INT32
NTAPI
IopArbIrqScoreRequirement(
    _In_ PIO_RESOURCE_DESCRIPTOR IoDescriptor)
{
    PAGED_CODE();
 
    return (INT32)(IoDescriptor->u.Interrupt.MaximumVector -
                   IoDescriptor->u.Interrupt.MinimumVector + 1);
}
 
NTSTATUS
NTAPI
IopArbIrqTranslateOrdering(
    _Out_ PIO_RESOURCE_DESCRIPTOR OutIoDescriptor,
    _In_ PIO_RESOURCE_DESCRIPTOR IoDescriptor)
{
    KIRQL Irql;
    KAFFINITY Affinity = 0;
 
    PAGED_CODE();
 
    *OutIoDescriptor = *IoDescriptor;
 
    if (IoDescriptor->Type != CmResourceTypeInterrupt)
        return STATUS_SUCCESS;
 
    OutIoDescriptor->u.Interrupt.MinimumVector =
        HalGetInterruptVector(Isa,
                              0,
                              IoDescriptor->u.Interrupt.MinimumVector,
                              IoDescriptor->u.Interrupt.MinimumVector,
                              &Irql,
                              &Affinity);
 
    if (Affinity != 0)
    {
        Affinity = 0;
        OutIoDescriptor->u.Interrupt.MaximumVector =
            HalGetInterruptVector(Isa,
                                  0,
                                  IoDescriptor->u.Interrupt.MaximumVector,
                                  IoDescriptor->u.Interrupt.MaximumVector,
                                  &Irql,
                                  &Affinity);
    }
 
    if (Affinity == 0)
        *OutIoDescriptor = *IoDescriptor;
 
    return STATUS_SUCCESS;
}
 
NTSTATUS
NTAPI
IopArbIrqInitialize(VOID)
{
    NTSTATUS Status;
 
    PAGED_CODE();
 
    IopRootIrqArbiter.Name = L"RootIRQ";
    IopRootIrqArbiter.UnpackRequirement = IopArbIrqUnpackRequirements;
    IopRootIrqArbiter.PackResource = IopArbIrqPackResource;
    IopRootIrqArbiter.UnpackResource = IopArbIrqUnpackResource;
    IopRootIrqArbiter.ScoreRequirement = IopArbIrqScoreRequirement;
 
    Status = ArbiterLibInitializeInstance(&IopRootIrqArbiter,
                                          NULL,
                                          CmResourceTypeInterrupt,
                                          IopRootIrqArbiter.Name,
                                          L"Root",
                                          IopArbIrqTranslateOrdering);
    if (!NT_SUCCESS(Status))
    {
        DPRINT1("IopArbIrqInitialize: Failed with %X\n", Status);
    }
 
    return Status;
}