ipa_imem_init(9)

📦 version 7.3.1, in nixpkgs unstable

💖 ipa_imem_init(9) 💖

okay so bestie, welcome to ipa_imem_init — that's section 9 of the Kernel API Manual, iykyk — and honestly? This little function is a whole vibe. It's the one that initializes the IMEM memory used by the IPA. ✨

🌸 SYNOPSIS 🌸

int ipa_imem_init (struct ipa *ipa , unsigned long addr , size_t size );

Like, that's it. Three args. She's lowkey elegant. 💅

🎀 ARGUMENTS 🎀

  • ipa — the IPA pointer. Your main character struct, fr. 🫶
  • addr — physical address of the IPA region in IMEM. yes, physical. 👀
  • size — size, in bytes, of the IPA region in IMEM. bytes, not vibes. 😭

🦋 DESCRIPTION 🦋

So here's the lore, bestie. IMEM is a block of shared memory that's separate from system DRAM, and a portion of this memory is available for the IPA to use. Not the whole thing — a portion. The way that detail matters. 💜

The modem accesses this memory directly. But the IPA? Nope. The IPA accesses it via the IOMMU, using the AP's credentials. Two different lanes, same memory. iconic behavior honestly. 🔥

And if this region exists — that's size > 0, mark it — we map it for read/write access through the IOMMU using the IPA device. That's the whole job. slay. 💅

⭐ NOTE ⭐

Heads up: addr and size are not guaranteed to be page-aligned. Not a bug, not a problem, just the truth — so don't go assuming alignment that isn't promised. 🙈

🌈 SEE ALSO 🌈

Kernel file ./drivers/net/ipa/ipa_mem.c plus the whole friend group:

go read them, they're literally right there. 🧚

💖 that's the whole page, bestie 💖 This one lives in ./drivers/net/ipa, dated October 2026 — no cap, that's the version and date, and it's giving official. 🎀✨🍓

📦 where this page comes from