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Use PCI BIOS Functions for Device Enumeration

hard5/8

Parse ACPI Tables for Hardware Discovery Use UEFI Boot Services and Memory Map

Language

Compiler

2.0s Limit 256MB

Submit and pass all tests to enable saving to GitHub.

Implementation

Implement PCI BIOS function calls in C.

Requirements:

Implement pci_bios_present() checking for "PCI " signature
Implement pci_find_device(vendor, device, index)
Implement pci_read_config(bus, dev, func, offset, size)
Implement pci_write_config(bus, dev, func, offset, value, size)
Show PCI BIOS version
Find a specific device by vendor/device ID
Read and print BAR values via PCI BIOS
Show error handling for device not found
Print bus/device/function of found devices

Test:

Show PCI BIOS present check
Show device found
Show config read
Show error handling

Why This Matters

Before MMCONFIG (MCFG-table-based memory-mapped PCI Express config space) became standard, this exact INT 0x1A/AH=0xB1 interface was how DOS device drivers and early Linux `pcibios_*` kernel routines enumerated hardware, and SeaBIOS still implements it today for legacy guest OS compatibility in QEMU. Getting the bus/dev/func encoding wrong here is the same bug class that once made PCI device drivers scan the wrong device by accident.

Hints

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Validation Suite

main.c

Workspace 1.0

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