add_cxl_resources(9)

🎀 NAME 🎀

add_cxl_resources — the glow-up that reflects CXL fixed memory windows in iomem_resource ✨

(also hi, this is from the Kernel API Manual, section 9, bestie 🫶)

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✨ SYNOPSIS ✨

int add_cxl_resources (struct resource *cxl_res );

Like, that's the whole call. Iconic, honestly 💅

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🦋 ARGUMENTS 🦋

• cxl_res — a standalone resource tree where each CXL window is a sibling 🌈 yes bestie, standalone, and yes, every CXL window sits in there as a sibling — that's the vibe check

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🌸 DESCRIPTION 🌸

okay so picture this: add_cxl_resources walks each CXL window in cxl_res and adds it to iomem_resource, potentially expanding its boundaries so that any conflicting resources become children 👑 it's giving "make room, the windows are moving in."

and like, here's the tea: if a window does get expanded, it may then conflict with another window entry 😭 which means that window has to get truncated or trimmed. not me causing drama just by expanding 💀

consider this situation:

            |-- "CXL Window 0" --||----- "CXL Window 1" -----|
            |--------------- "System RAM" -------------|

...where platform firmware has established as System RAM resource across 2 windows, but has left some portion of window 1 for dynamic CXL region provisioning 🧚 in this case "Window 0" will span the entirety of the "System RAM" span, and "CXL Window 1" is truncated to the remaining tail past the end of that "System RAM" resource. periodt 💜

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🔥 SEE ALSO 🔥

• Kernel file ./drivers/cxl/acpi.c
• cxl_acpi_evaluate_qtg_dsm(9)

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okay that's the whole page bestie, no notes 💖 this came to you from ./drivers/cxl, October 2026 — go forth and slay your resource trees 🎀✨🦋