of_pci_preserve_config(9)

okay so this is of_pci_preserve_config(9) from the Kernel API Manual, and it's giving “tiny helper, huge boot-config energy” 💅✨

🎀 NAME 🎀

of_pci_preserve_config — return true if the boot configuration needs to be preserved. literally that's the whole vibe, bestie.

✨ SYNOPSIS ✨

bool of_pci_preserve_config (struct device_node *node );

🌸 ARGUMENTS 🌸

• node — the Device tree node in question. that's the one you're checking, no cap.

🦋 DESCRIPTION 🦋

okay so here's the tea: this function looks for the "linux,pci-probe-only" property on a given PCI controller's node, and returns true if it finds it. 👑

It also looks in the chosen node if that property is not found in the given controller's node. yep, it checks both spots. 🫶

Having this property ensures that the kernel doesn't reconfigure the BARs and bridge windows that are already done by the platform firmware. periodt — leave the firmware's work alone. 💅

💖 RETURN 💖

• true if the property exists.
• false otherwise.

🌈 SEE ALSO 🌈

Kernel file: ./drivers/pci/of.c

• pci_set_of_node(9)
• of_pci_get_devfn(9)
• of_pci_parse_bus_range(9)
• of_get_pci_domain_nr(9)
• of_pci_check_probe_only(9)
• devm_of_pci_get_host_bridge_resources(9)
• of_irq_parse_pci(9)
• of_irq_parse_and_map_pci(9)
• of_pci_supply_present(9)
• of_pci_get_max_link_speed(9)
• of_pci_get_slot_power_limit(9)
• of_pci_get_equalization_presets(9)

signing off from ./drivers/pci — October 2026, bestie — of_pci_preserve_config(9) out 💅🎀✨