dce_v10_0_pick_pll(9)

📦 version 7.3.1, in nixpkgs unstable

💅 dce_v10_0_pick_pll(9) — like, the Kernel API Manual one, bestie

okay so picture this: it's a Kernel API Manual page, the star of the show is dce_v10_0_pick_pll, and she is literally the girl who hands out PPLLs to crtcs. group chat, but make it DRM. let's go ✨

🌸 NAME 🌸

dce_v10_0_pick_pll — allocate a PPLL for use by the crtc. that's it. that's the whole job. icon behavior honestly 👑

🎀 SYNOPSIS 🎀

u32 dce_v10_0_pick_pll (struct drm_crtc *crtc );

she takes one thing and gives you back a u32. simple. elegant. slay 💅

🦋 ARGUMENTS 🦋

  • crtc — a drm crtc. that's the whole description, no notes, she said what she said 🫶

✨ DESCRIPTION ✨

okay so here's the tea, bestie: this function returns the PPLL (that's Pixel PLL, iykyk) that the crtc is gonna use. 🎀

for DP monitors, a single PPLL can be used for all DP crtcs/encoders — one PLL serving the whole group chat, very efficient, we love to see it. for non-DP monitors though? nope. a dedicated PPLL must be used. no sharing, no borrowing, everyone gets their own. 🙈

and if a particular board has an external DP PLL, she returns ATOM_PPLL_INVALID to skip PLL programming — because there's literally no need to program the PLL itself. why do the work when the board already did it, right? 💀

and lastly, if we are not able to allocate a PLL, she also returns ATOM_PPLL_INVALID to skip PLL programming — and that's on purpose, to avoid messing up an existing monitor. protective queen. we stan. 👑

⭐ Asic specific PLL information ⭐

🔥 DCE 10.x Tonga 🔥

  • PPLL1, PPLL2 are available for all UNIPHY (both DP and non-DP) CI
  • PPLL0, PPLL1, PPLL2 are available for all UNIPHY (both DP and non-DP) and DAC

like, look at PPLL0 joining the party in the second one. main character energy fr fr 🌈

🌟 SEE ALSO 🌟

the whole friend group, in this exact order, no cap:

Kernel file ./drivers/gpu/drm/amd/amdgpu/dce_v10_0.c

ok that's the page!! 💖 this lil masterpiece lives in ./drivers/gpu/drm/amd/amdgpu and it's dated October 2026 — yes, the future, because she's ahead of her time. bye bestie, go allocate some PLLs responsibly 🧚‍♀️🍓
📦 where this page comes from