fdt_setprop_inplace_u64(9)

📦 version 7.3.1, in nixpkgs unstable

💅 fdt_setprop_inplace_u64 💅

okay bestie, so this page is from the Kernel API Manual and it's all about fdt_setprop_inplace_u64(9) — literally the glow-up your 64-bit integer property has been waiting for. no cap. 🎀

✨ NAME ✨

fdt_setprop_inplace_u64 — change the value of a 64-bit integer property

🦋 SYNOPSIS 🦋

int fdt_setprop_inplace_u64 (void *fdt , int nodeoffset , const char
*name , uint64_t val );

🌸 ARGUMENTS 🌸

  • fdt — pointer to the device tree blob. yes queen, the whole tree 💖
  • nodeoffset — offset of the node whose property to change. like, which node are we touching
  • name — name of the property to change. the actual thing you're editing
  • val — 64-bit integer value to replace the property with. the new content, iconic ✨

💅 DESCRIPTION 💅

so fdt_setprop_inplace_u64 replaces the value of a given property with the 64-bit integer value in val, converting val to big-endian if necessary. she's inclusive like that 🫶

⚠️ and this is the important part, bestie: this function cannot change the size of a property. so it will only work if the property already exists and has length 8. it's giving "in-place only, no room to grow," iykyk 😭

also this function will alter only the bytes in the blob which contain the given property value, and will not alter or move any other part of the tree. respectful. considerate. she minds her own business 💜

🔥 RETURN 🔥

  • 0 — on success, slay 💀✨
  • -FDT_ERR_NOSPACE — if the property's length is not equal to 8
  • -FDT_ERR_NOTFOUND — node does not have the named property
  • -FDT_ERR_BADOFFSET — nodeoffset did not point to FDT_BEGIN_NODE tag
  • -FDT_ERR_BADMAGIC, -FDT_ERR_BADVERSION, -FDT_ERR_BADSTATE, -FDT_ERR_BADSTRUCTURE, -FDT_ERR_TRUNCATED — standard meanings

👑 SEE ALSO 👑

Kernel file ./scripts/dtc/libfdt/libfdt.h and honestly the whole friend group:

and that's the whole page, bestie 🧚 no notes, ate and left no crumbs ✨

this lil masterpiece lives in ./scripts/dtc/libfdt and it's dated October 2026 — so yeah, go forth and set those 64-bit props in place 💖🎀🦋

📦 where this page comes from