intel_check_...fo_underruns(9)

💖 intel_check_cpu_fifo_underruns(9) 💖

okay bestie, we're in the Kernel API Manual and the page header is doing its lil truncated thing: intel_check_...fo_underruns(9). The actual main character is intel_check_cpu_fifo_underruns, and she's here to check for CPU fifo underruns immediately. periodt 💅

✨ NAME ✨

• intel_check_cpu_fifo_underruns — check for CPU fifo underruns immediately

🎀 SYNOPSIS 🎀

the whole flex is literally this:

void intel_check_cpu_fifo_underruns (struct intel_display *display );

🦋 ARGUMENTS 🦋

• display — display device instance. that's the vibe, that's the parameter 🫶

💅 DESCRIPTION 💅

Bestie, this function checks for CPU fifo underruns immediately. No waiting around, no "let me get back to you" energy — immediate. ⚡

It's useful on IVB/HSW where the shared error interrupt may have been disabled, and so CPU fifo underruns won't necessarily raise an interrupt, and on GMCH platforms where underruns never raise an interrupt. so yeah, sometimes the interrupt is lowkey not coming to the group chat 😭

🌈 SEE ALSO 🌈

Kernel file ./drivers/gpu/drm/i915/display/intel_fifo_underrun.c and fifo underrun handling(9) are the source-adjacent besties, and then we've got the whole underrun-reporting friend group:

• intel_set_cpu_fifo_underrun_reporting(9)
• intel_set_pch_fifo_underrun_reporting(9)
• intel_cpu_fifo_underrun_irq_handler(9)
• intel_pch_fifo_underrun_irq_handler(9)
• intel_check_pch_fifo_underruns(9)

mwah 💋 cute lil sign-off: this page's source/version-ish footer energy points at ./drivers/gpu/drm/i915/display, it's dated October 2026, and the header tag is still out here being intel_check_...fo_underruns(9). slay, go check those underruns ✨👑