drm_fb_dma_s...non_coherent(9)

💅 drm_fb_dma_s...non_coherent(9) — Kernel API Manual, section 9

okay so bestie, welcome to the glow-up era of this lil kernel API page ✨ this one lives in the Kernel API Manual, section 9, and it's genuinely so niche but so real.

---

🎀 NAME 🎀

drm_fb_dma_sync_non_coherent — sync a GEM object to non-coherent backing memory. that's it, that's the whole vibe 🫶

---

✨ SYNOPSIS ✨

void drm_fb_dma_sync_non_coherent (struct drm_device *drm , struct
drm_plane_state *old_state , struct drm_plane_state *state );

no cap, that's the exact signature, character for character 💅

---

🌸 ARGUMENTS 🌸

• drm — the DRM device. your main character, lowkey 👑
• old_state — the old plane state. the before pic 🙈
• state — the new plane state. the after pic ✨

---

🦋 DESCRIPTION 🦋

okay so here's the tea: this function is for drivers that use damage clips and have DMA GEM objects backed by non-coherent memory. very specific combo, we love a niche icon 💖

call this function in a plane's .atomic_update and it makes sure that all the data in the backing memory has been written to RAM. literally that's the whole job, and it ate 🔥

---

🌈 SEE ALSO 🌈

• Kernel file ./drivers/gpu/drm/drm_fb_dma_helper.c — framebuffer dma helper functions(9)
• drm_fb_dma_get_gem_obj(9)
• drm_fb_dma_get_gem_addr(9)
• drm_fb_dma_get_scanout_buffer(9)

iykyk, go read the whole friend group 💜

---

⭐ reminder: the behaviour above is exactly what the page says — no extra lore, no invented tips, fr fr.

---

and that's a wrap, bestie 🎀 this page belongs to ./drivers/gpu/drm, dated October 2026, filed under drm_fb_dma_s...non_coherent(9) — mwah, periodt 💅🌟