NTSTATUS NTAPI PciQueryResources	(	IN PPCI_PDO_EXTENSION	PdoExtension,
		OUT PCM_RESOURCE_LIST *	Buffer
	)
Definition at line 355 of file enum.c.
Referenced by PciPdoIrpQueryResources().
{
    PPCI_FUNCTION_RESOURCES PciResources;
    BOOLEAN HaveVga, HaveMemSpace, HaveIoSpace;
    USHORT BridgeControl, PciCommand;
    ULONG Count, i;
    PCM_PARTIAL_RESOURCE_DESCRIPTOR Partial, Resource, LastResource;
    PCM_RESOURCE_LIST ResourceList;
    UCHAR InterruptLine;
    PAGED_CODE();

    /* Assume failure */
    Count = 0;
    HaveVga = FALSE;
    *Buffer = NULL;

    /* Make sure there's some resources to query */
    PciResources = PdoExtension->Resources;
    if (!PciResources) return STATUS_SUCCESS;

    /* Read the decodes */
    PciReadDeviceConfig(PdoExtension,
                        &PciCommand,
                        FIELD_OFFSET(PCI_COMMON_HEADER, Command),
                        sizeof(USHORT));

    /* Check which ones are turned on */
    HaveIoSpace = PciCommand & PCI_ENABLE_IO_SPACE;
    HaveMemSpace = PciCommand & PCI_ENABLE_MEMORY_SPACE;

    /* Loop maximum possible descriptors */
    for (i = 0; i < 7; i++)
    {
        /* Check if the decode for this descriptor is actually turned on */
        Partial = &PciResources->Current[i];
        if (((HaveMemSpace) && (Partial->Type == CmResourceTypeMemory)) ||
            ((HaveIoSpace) && (Partial->Type == CmResourceTypePort)))
        {
            /* One more fully active descriptor */
            Count++;
        }
    }

    /* If there's an interrupt pin associated, check at least one decode is on */
    if ((PdoExtension->InterruptPin) && ((HaveMemSpace) || (HaveIoSpace)))
    {
        /* Read the interrupt line for the pin, add a descriptor if it's valid */
        InterruptLine = PdoExtension->AdjustedInterruptLine;
        if ((InterruptLine) && (InterruptLine != -1)) Count++;
    }

    /* Check for PCI bridge */
    if (PdoExtension->HeaderType == PCI_BRIDGE_TYPE)
    {
        /* Read bridge settings, check if VGA is present */
        PciReadDeviceConfig(PdoExtension,
                            &BridgeControl,
                            FIELD_OFFSET(PCI_COMMON_HEADER, u.type1.BridgeControl),
                            sizeof(USHORT));
        if (BridgeControl & PCI_ENABLE_BRIDGE_VGA)
        {
            /* Remember for later */
            HaveVga = TRUE;

            /* One memory descriptor for 0xA0000, plus the two I/O port ranges */
            if (HaveMemSpace) Count++;
            if (HaveIoSpace) Count += 2;
        }
    }

    /* If there's no descriptors in use, there's no resources, so return */
    if (!Count) return STATUS_SUCCESS;

    /* Allocate a resource list to hold the resources */
    ResourceList = PciAllocateCmResourceList(Count,
                                             PdoExtension->ParentFdoExtension->BaseBus);
    if (!ResourceList) return STATUS_INSUFFICIENT_RESOURCES;

    /* This is where the descriptors will be copied into */
    Resource = ResourceList->List[0].PartialResourceList.PartialDescriptors;
    LastResource = Resource + Count + 1;

    /* Loop maximum possible descriptors */
    for (i = 0; i < 7; i++)
    {
        /* Check if the decode for this descriptor is actually turned on */
        Partial = &PciResources->Current[i];
        if (((HaveMemSpace) && (Partial->Type == CmResourceTypeMemory)) ||
            ((HaveIoSpace) && (Partial->Type == CmResourceTypePort)))
        {
            /* Copy the descriptor into the resource list */
            *Resource++ = *Partial;
        }
    }

    /* Check if earlier the code detected this was a PCI bridge with VGA on it */
    if (HaveVga)
    {
        /* Are the memory decodes enabled? */
        if (HaveMemSpace)
        {
            /* Build a memory descriptor for a 128KB framebuffer at 0xA0000 */
            Resource->Flags = CM_RESOURCE_MEMORY_READ_WRITE;
            Resource->u.Generic.Start.HighPart = 0;
            Resource->Type = CmResourceTypeMemory;
            Resource->u.Generic.Start.LowPart = 0xA0000;
            Resource->u.Generic.Length = 0x20000;
            Resource++;
        }

        /* Are the I/O decodes enabled? */
        if (HaveIoSpace)
        {
            /* Build an I/O descriptor for the graphic ports at 0x3B0 */
            Resource->Type = CmResourceTypePort;
            Resource->Flags = CM_RESOURCE_PORT_POSITIVE_DECODE | CM_RESOURCE_PORT_10_BIT_DECODE;
            Resource->u.Port.Start.QuadPart = 0x3B0u;
            Resource->u.Port.Length = 0xC;
            Resource++;

            /* Build an I/O descriptor for the graphic ports at 0x3C0 */
            Resource->Type = CmResourceTypePort;
            Resource->Flags = CM_RESOURCE_PORT_POSITIVE_DECODE | CM_RESOURCE_PORT_10_BIT_DECODE;
            Resource->u.Port.Start.QuadPart = 0x3C0u;
            Resource->u.Port.Length = 0x20;
            Resource++;
        }
    }

    /* If there's an interrupt pin associated, check at least one decode is on */
    if ((PdoExtension->InterruptPin) && ((HaveMemSpace) || (HaveIoSpace)))
    {
         /* Read the interrupt line for the pin, check if it's valid */
         InterruptLine = PdoExtension->AdjustedInterruptLine;
         if ((InterruptLine) && (InterruptLine != -1))
         {
             /* Make sure there's still space */
             ASSERT(Resource < LastResource);

             /* Add the interrupt descriptor */
             Resource->Flags = CM_RESOURCE_INTERRUPT_LEVEL_SENSITIVE;
             Resource->Type = CmResourceTypeInterrupt;
             Resource->ShareDisposition = CmResourceShareShared;
             Resource->u.Interrupt.Affinity = -1;
             Resource->u.Interrupt.Level = InterruptLine;
             Resource->u.Interrupt.Vector = InterruptLine;
        }
    }

    /* Return the resouce list */
    *Buffer = ResourceList;
    return STATUS_SUCCESS;
}
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