Specifications

76 AMD Geode™ GeodeROM Functional Specification
PCI Support
32087C
7.1.2 Subfunction 02h - Find PCI Device
Description:
Given a vendor ID, device ID, and an index N, the function Find PCI Device finds the Nth device or function whose ven-
dor ID and device ID match those passed into the function. Additionally, Find PCI Device returns the bus number,
device number, and function number of the device if it successfully finds a match.
This function is useful for locating all PCI devices in the system that perform the same function. The first return value of
DEVICE_NOT_FOUND indicates there are no more devices of the type specified in the system.
Passed:
Returns:
Parameter Description
AH B1h (PCI Function ID)
AL 02h (Find PCI Device)
CX 16-Bit device ID
DX 16-Bit vendor ID
SI Index N (Nth occurrence of PCI device)
Parameter Description
BH Bus number of device (0-based)
BL Bits [7:3] = Device number
Bits [2:0] = Function number within located device
CF Function completion status:
0 if device was located
1 if an error occurred, AH contains error code
AH Function return status codes:
00h = Successful
81h = Unsupported function
83h = Bad vendor ID
86h = Device not found
87h = Bad PCI register number