amdgpu_mm_rdoorbell64(9)

💅 amdgpu_mm_rdoorbell64 — bestie's guide to the kernel API manual ✨

okay so real talk, this is a page from the Kernel API Manual and it's literally about amdgpu_mm_rdoorbell64, which reads a doorbell Qword. yes, a Qword. 64 bits of doorbell goodness. we're in the kernel, it's giving low-level, and honestly? iconic. 🎀

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✨ NAME ✨

amdgpu_mm_rdoorbell64 — read a doorbell Qword 🦋

like literally that's the whole job. read. doorbell. Qword. no cap.

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🌸 SYNOPSIS 🌸

u64 amdgpu_mm_rdoorbell64 (struct amdgpu_device *adev , u32 index );

look at her. u64 return type, two args, clean, unbothered, moisturised. 💖

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🫶 ARGUMENTS 🫶

• adev — an amdgpu_device pointer. your whole GPU situation, basically. 💅
• index — the doorbell index. which doorbell we're reading, bestie. 🔔

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🔥 DESCRIPTION 🔥

Returns the value in the doorbell aperture at the requested doorbell index (VEGA10+). ⭐

that's it. that's the whole vibe. you point at a doorbell index, it hands you back whatever's chillin' in the doorbell aperture. and note the (VEGA10+) — this is a VEGA10-and-later situation, so don't come at her with your ancient hardware, she's not doing that. 💀

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🌈 SEE ALSO 🌈

• Kernel file ./drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c — the source, the origin, the main character. 👑
• amdgpu_mm_rdoorbell(9)
• amdgpu_mm_wdoorbell(9)
• amdgpu_mm_wdoorbell64(9)
• amdgpu_doorbell_index_on_bar(9)
• amdgpu_doorbell_create_kernel_doorbells(9)
• amdgpu_doorbell_init(9)
• amdgpu_doorbell_fini(9)

the whole doorbell friend group, fr fr. go read them too, iykyk. 🧚

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🍓 the sign-off 🍓

this little masterpiece lives in ./drivers/gpu/drm/amd/amdgpu, and the page itself is dated October 2026. that's the version and the date, babes — mentioned exactly like i promised. now go read a doorbell. slay. 💜✨