STRUCT XHCI_RUN_REGS(9)

✨ NAME ✨

struct xhci_run_regs — okay so bestie, this is the struct for the Host Controller Runtime Registers 💅 and yes, this page is coming in with Kernel API Manual energy the whole way through, so buckle up 🎀

Real talk though: the original NAME line is struct xhci_run_regs - with literally nothing after the dash. Not a typo, not me being lazy, that's just how it is. The description has the deets instead. 🙈

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✨ SYNOPSIS ✨

struct xhci_run_regs {
    __le32 microframe_index;
    __le32 rsvd[7];
    struct xhci_intr_reg    ir_set[1024];
 };

Look at her. Iconic. A little __le32 moment, a lil rsvd[7] for the reserved homies, and then ir_set[1024] just absolutely serving 1024 interrupt register sets like the main character she is 👑

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🫶 Members 🫶

• microframe_index — this is MFINDEX, and it's holding the current microframe number. That's it. That's the whole documented member. The rsvd[7] and ir_set[1024] are out here living undocumented lives (the original page only spells out this one), so no cap, don't come for me for not inventing lore 😭

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🌸 DESCRIPTION 🌸

Straight from Section 5.5 Host Controller Runtime Registers, and I'm quoting this exactly because the spec said what it said:

"Software should read and write these registers using only Dword (32 bit) or larger accesses"

Bestie. Read that again. Dword (32 bit) or larger accesses ONLY. No cute little byte-sized pokes, no nibbling on it with a u8. The spec was very clear and honestly a little scary about it 💀 So keep your accesses thicc and aligned, iykyk.

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🦋 SEE ALSO 🦋

• Kernel file ./drivers/usb/host/xhci.h
• struct xhci_cap_regs(9)
• struct xhci_op_regs(9)
• struct xhci_intr_reg(9)
• struct xhci_container_ctx(9)
• struct xhci_slot_ctx(9)
• struct xhci_ep_ctx(9)
• struct xhci_device_context_array(9)

Go read the whole xHCI friend group, they're all connected and honestly the lore is deep 🌈✨

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💖 that's the whole page bestie, slay 💖

This one lives in ./drivers/usb/host, dated October 2026, and it's the struct xhci_run_regs(9) page from the Kernel API Manual — go off, microframe queen 👑🦋🍓