3  * Module Name: hwpci - Obtain PCI bus, device, and function numbers
11  * Some or all of this work - Copyright (c) 1999 - 2025, Intel Corp.
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160 /* PCI configuration space values */
166 /* PCI header values */
209  * PARAMETERS:  PciId               - Initial values for the PCI ID. May be
211  *              RootPciDevice       - A handle to a PCI device object. This
212  *                                    object must be a PCI Root Bridge having a
214  *              PciRegion           - A handle to a PCI configuration space
219  * DESCRIPTION: This function derives a full PCI ID for a PCI device,
223  *              The PCI hardware dynamically configures PCI bus numbers
234  *              Function number PCI ID subfields as appropriate for the
238  *              interface since this feature is OS-independent. This module
262     /* Build a list of PCI devices, from PciRegion up to RootPciDevice */  in AcpiHwDerivePciId()
267         /* Walk the list, updating the PCI device/function/bus numbers */  in AcpiHwDerivePciId()
284  * PARAMETERS:  RootPciDevice       - A handle to a PCI device object. This
285  *                                    object is guaranteed to be a PCI Root
288  *              PciRegion           - A handle to the PCI configuration space
290  *              ReturnListHead      - Where the PCI device list is returned
294  * DESCRIPTION: Builds a list of devices from the input PCI region up to the
295  *              Root PCI device for this namespace subtree.
313      * a list of device nodes. Loop will exit when either the PCI device is  in AcpiHwBuildPciList()
329         /* Finished when we reach the PCI root device (PNP0A03 or PNP0A08) */  in AcpiHwBuildPciList()
347         ListElement->Next = *ReturnListHead;  in AcpiHwBuildPciList()
348         ListElement->Device = ParentDevice;  in AcpiHwBuildPciList()
360  * PARAMETERS:  PciId               - Initial values for the PCI ID. May be
362  *              ListHead            - Device list created by
367  * DESCRIPTION: Walk downward through the PCI device list, getting the device
368  *              info for each, via the PCI configuration space and updating
369  *              the PCI ID as necessary. Deletes the list during traversal.
389         PciId->Segment, PciId->Bus, PciId->Device, PciId->Function));  in AcpiHwProcessPciList()
391     BusNumber = PciId->Bus;  in AcpiHwProcessPciList()
394      * Descend down the namespace tree, collecting PCI device, function,  in AcpiHwProcessPciList()
395      * and bus numbers. BusNumber is only important for PCI bridges.  in AcpiHwProcessPciList()
396      * Algorithm: As we descend the tree, use the last valid PCI device,  in AcpiHwProcessPciList()
398      * to the PCI ID for the target device.  in AcpiHwProcessPciList()
403         Status = AcpiHwGetPciDeviceInfo (PciId, Info->Device,  in AcpiHwProcessPciList()
410         Info = Info->Next;  in AcpiHwProcessPciList()
416         PciId->Segment, PciId->Bus, PciId->Device, PciId->Function,  in AcpiHwProcessPciList()
427  * PARAMETERS:  ListHead            - Device list created by
432  * DESCRIPTION: Free the entire PCI list.
448         Next = Previous->Next;  in AcpiHwDeletePciList()
458  * PARAMETERS:  PciId               - Initial values for the PCI ID. May be
460  *              PciDevice           - Handle for the PCI device object
461  *              BusNumber           - Where a PCI bridge bus number is returned
462  *              IsBridge            - Return value, indicates if this PCI
463  *                                    device is a PCI bridge
467  * DESCRIPTION: Get the device info for a single PCI device object. Get the
468  *              _ADR (contains PCI device and function numbers), and for PCI
469  *              bridge devices, get the bus number from PCI configuration
510      * From _ADR, get the PCI Device and Function and  in AcpiHwGetPciDeviceInfo()
511      * update the PCI ID.  in AcpiHwGetPciDeviceInfo()
513     PciId->Device = ACPI_HIWORD (ACPI_LODWORD (ReturnValue));  in AcpiHwGetPciDeviceInfo()
514     PciId->Function = ACPI_LOWORD (ACPI_LODWORD (ReturnValue));  in AcpiHwGetPciDeviceInfo()
522         PciId->Bus = *BusNumber;  in AcpiHwGetPciDeviceInfo()
526      * Get the bus numbers from PCI Config space:  in AcpiHwGetPciDeviceInfo()
528      * First, get the PCI HeaderType  in AcpiHwGetPciDeviceInfo()
558     PciId->Bus = (UINT16) PciValue;  in AcpiHwGetPciDeviceInfo()