mlx4_en_phc_adjfine(9)

📦 version 7.3.1, in nixpkgs unstable

💖 mlx4_en_phc_adjfine(9) — from the Kernel API Manual, bestie 💖

okay so we're in the Kernel API Manual today and the page is mlx4_en_phc_adjfine(9). grab a lil snack, this one's short and sweet 🍓

✨ NAME ✨

mlx4_en_phc_adjfine — adjust the frequency of the hardware clock

like, we're literally just nudging the clock's vibe (its frequency) so it stops drifting. no cap. 🕰️

🎀 SYNOPSIS 🎀

int mlx4_en_phc_adjfine (struct ptp_clock_info *ptp , long scaled_ppm );

it returns an int, it takes two things, and yes the spacing is exactly like that — don't come for me, I'm copying the icon 💅

🦋 ARGUMENTS 🦋

  • ptp — the ptp clock structure. this is the main character of the whole operation, the clock we're about to tweak 💫
  • scaled_ppm — the desired frequency change in scaled parts per million. so not regular ppm, scaled ppm — keep reading, I promise it makes sense 🌸

🔥 DESCRIPTION 🔥

So here's the tea ☕: this function adjusts the frequency of the PHC cycle counter by the indicated scaled_ppm from the base frequency. that's it, that's the whole job — a little nudge away from base, in either direction, no dramatic main-character overhaul.

And in case you were wondering what the heck "scaled" means here (because I know you were):

Scaled parts per million is ppm with a 16-bit binary fractional field.

so it's ppm with a 16-bit fractional bit of extra precision stapled on. fancy ppm. posh ppm. ppm that went to finishing school 🎀✨

👑 SEE ALSO 👑

kernel file ./drivers/net/ethernet/mellanox/mlx4/en_clock.c — go read the source, it's giving lore 📖

and these absolute icons, all in the same friend group:

iykyk 💜

aaaand that's the whole page, bestie, you ate that 🫶 source line lives at ./drivers/net/ethernet/mellano... (truncated in the original, don't @ me 😭), dated October 2026, and the page is mlx4_en_phc_adjfine(9) — mwah, go adjust some frequencies responsibly ⭐🌈💖

📦 where this page comes from