rtas_config_addr(9)

💅 rtas_config_addr(9) — Kernel API Manual

okay bestie, welcome to the rtas_config_addr page ✨ this is a kernel API manual entry, and honestly? she's short, she's sweet, and she does exactly one thing. let's get into it 🎀

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🌸 NAME 🌸

rtas_config_addr — format a busno, devfn and reg for RTAS. literally that's her whole job 💖

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✨ SYNOPSIS ✨

u32 rtas_config_addr (int busno , int devfn , int reg );

so you hand her three ints and she gives you back a u32. cute, clean, no cap.

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🦋 ARGUMENTS 🦋

• busno — the bus number. that's it, that's the whole argument 🚌
• devfn — the device and function number, as encoded by PCI_DEVFN. yes, as encoded by PCI_DEVFN — don't come in here with your own handmade encoding, she will notice 🙈
• reg — the register number. the third and final int, we love a trio 👑

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💜 DESCRIPTION 💜

so what does she actually do? she takes the busno, the devfn and the register number you gave her and encodes them ~exactly the way~ they need to be encoded for RTAS calls that take a "config_addr" parameter. that's the whole vibe check: if an RTAS call wants a "config_addr", this is the girl who makes one for you 💅

and if you want the receipts on why it's encoded like that, go read PAPR requirement 7.3.4-1 — the original text literally points you there for more info, so like… go read it, bestie 📖

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🔥 SEE ALSO 🔥

• Kernel file ./arch/powerpc/include/asm/rtas.h — go look at the header if you're nosy (affectionate) 👀

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and that's the whole page, bestie 🫶 stay iconic, encode responsibly, and remember: rtas_config_addr(9) came to you from the ./arch/powerpc/include/asm corner of the kernel, dated October 2026 — mwah, see you in the next manpage 💋🌸✨