amdgpu_ttm_access_memory(9)

💅 amdgpu_ttm_access_memory (9) — the Kernel API Manual, but make it cute

okay so bestie, welcome to the Kernel API Manual page for amdgpu_ttm_access_memory — yes that's a mouthful, yes you'll get it, and yes it's lowkey iconic once you do 🎀

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✨ NAME ✨

amdgpu_ttm_access_memory — Read or Write memory that backs a buffer object. that's it, that's the whole vibe 🦋

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🌸 SYNOPSIS 🌸

int amdgpu_ttm_access_memory (struct ttm_buffer_object *bo , unsigned
long offset , void *buf , int len , int write );

like, she takes five arguments and returns an int. main character energy fr fr 👑

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💖 ARGUMENTS 💖

• bo — The buffer object to read/write 💫 that's the thing you're poking at.
• offset — Offset into buffer object. where inside the BO you're poking, basically a little address from the start 🎯
• buf — Secondary buffer to write/read from. this is the other side of the transaction — the memory you're copying to or from 🫶
• len — Length in bytes of access. how many bytes we're moving, no more no less ⭐
• write — true if writing. so if it's set, you're writing; otherwise you're reading. simple as 🙈

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🦋 DESCRIPTION 🦋

This is used to access VRAM that backs a buffer object via MMIO access for debugging purposes.

not me explaining MMIO 😭 okay so the whole point here is: you've got VRAM sitting behind a buffer object, and this function lets you reach into it through MMIO — which is straight-up register-style memory-mapped poking, no fancy shmancy paths — and it exists for debugging purposes. so like, it's the "i need to actually look at what's in VRAM right now" tool. debugging bestie behavior, we love to see it 💅✨

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🌈 SEE ALSO 🌈

the kernel file itself lives at:

./drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c

and here's the whole friend group, all tagged (9) because they're all kernel-doc'd like that 👯‍♀️:

• amdgpu_evict_flags(9)
• amdgpu_ttm_map_buffer(9)
• amdgpu_ttm_copy_mem_to_mem(9)
• amdgpu_res_cpu_visible(9)
• amdgpu_ttm_domain_start(9)
• amdgpu_ttm_mmio_remap_alloc_sgt(9)
• amdgpu_ttm_tt_create(9)
• amdgpu_ttm_tt_get_userptr(9)
• amdgpu_ttm_tt_set_userptr(9)
• amdgpu_ttm_tt_pde_flags(9)
• amdgpu_ttm_tt_pte_flags(9)
• amdgpu_ttm_training_reserve_vram_fini(9)
• amdgpu_ttm_alloc_mmio_remap_bo(9)
• amdgpu_ttm_free_mmio_remap_bo(9)
• amdgpu_ttm_enable_buffer_funcs(9)
• amdgpu_ttm_disable_buffer_funcs(9)
• amdgpu_ttm_clear_buffer(9)
• amdgpu_ttm_evict_resources(9)

like wow, that's a whole squad and they all showed up 💀💜

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ngl bestie, the whole page is short and sweet — one function, five args, one debugging purpose. memorize the vibe, copy the names exactly, and you're slaying 🧚‍♀️

source: ./drivers/gpu/drm/amd/amdgpu · dated October 2026 · and that's the whole page, mwah 💋🍓 periodt ✨💅🎀