DALSMC_MSG_S...ptimizations(9)

📦 version 7.3.1, in nixpkgs unstable

✨ DALSMC_MSG_SetDisplayIdleOptimizations ✨

okay so bestie, welcome to the Kernel API Manual — this is the page filed under DALSMC_MSG_S...ptimizations(9) (yes the title got cut off, she's mysterious like that 💅) and honestly? she's short but she matters. let's get into it 🫶

🌸 NAME 🌸

DALSMC_MSG_SetDisplayIdleOptimizations — the girl whose whole job is to tell PMFW what's up with DCN idle-state conditions. like, "hey bestie, here's what's currently safe to power down." no cap.

🎀 SYNOPSIS 🎀

DALSMC_MSG_SetDisplayIdleOptimizations

that's it. that's the whole synopsis. she's lowkey iconic for that 💀

🦋 DESCRIPTION 🦋

okay so here's the vibe: this message indicates which display-side power optimizations are currently safe to apply. PMFW takes these flags and uses them to gate deeper SoC power states such as S0i2. so basically nothing deep-sleeps unless this girl says it's chill first. gatekeeping, but make it power management 👑

here's the actual payload, flag by flag, no details skipped because we don't do that here:

  • Request:
    • DfRequestDisabled[0] — DF (data fabric) requests from DCN are disabled
    • PhyRefClkOff[1] — PHY reference clock has been gated off
    • S0i2Rdy[2] — DCN is ready for the system to enter S0i2
  • Response: (none beyond result code)

the response is literally just the result code, she gives you nothing else and honestly? respect. 🙈

note: those bracketed numbers are bit positions, so don't go reading them as array indices, bestie. iykyk.

🌈 SEE ALSO 🌈

the source vibes live in the kernel file ./drivers/gpu/drm/amd/display/dc/clk_mgr/dcn60/dalsmc.h — go look, she's right there 🧚

and her whole friend group, in order, because we love a complete list:

and that's the page!! sourced from ./drivers/gpu/drm/amd/display/..., dated October 2026, filed as DALSMC_MSG_S...ptimizations(9). slay, go read the other ones too, mwah 💖🎀🦋✨

📦 where this page comes from