amdgpu_ttm_a...mio_remap_bo(9)

💅 amdgpu_ttm_alloc_mmio_remap_bo — the Kernel API Manual, but make it make sense

okay so bestie, welcome to amdgpu_ttm_a...mio_remap_bo(9) — yes that's the real truncated title, no I did not do that, the manpage did. we're in the Kernel API Manual today and this function is lowkey a lil' one-job icon. let's get into it ✨

---

🌸 NAME

amdgpu_ttm_alloc_mmio_remap_bo — literally just "Allocate the singleton MMIO_REMAP BO". that's it. that's the whole assignment. one BO, allocated, singular, iconic. 👑

---

🦋 SYNOPSIS

int amdgpu_ttm_alloc_mmio_remap_bo (struct amdgpu_device *adev );

like… that's the whole call. one argument. she's minimal. she's clean. she knows what she wants. 💅

---

🎀 ARGUMENTS

• adev — the amdgpu device. that's your whole context bestie, everything you need to know lives in there. 🫶

---

✨ DESCRIPTION

so here's the tea ☕: this function allocates a global BO with backing AMDGPU_PL_MMIO_REMAP — but only when two conditions are both serving looks:

1. the hardware actually exposes a remap base (that's adev->rmmio_remap.bus_addr), and
2. the host PAGE_SIZE is <= AMDGPU_GPU_PAGE_SIZE (4K).

both or nothing, no cap. 🚦

and the way it makes the BO? it's created as a regular GEM object via amdgpu_bo_create. nothing weird, nothing cursed, just a normal GEM object doing normal GEM object things. 🧚

---

🌈 RETURN

• 0 — on success or an intentional skip (like, the feature isn't present / isn't supported — she chose peace, and that's still a win 💖)
• negative errno — on allocation failure 😭 (the BO did not eat, and we're all sad about it)

---

🍓 SEE ALSO

the source of truth lives right here, bestie:

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

and the whole friend group, in order, no one left out:

• 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_access_memory(9)
• amdgpu_ttm_training_reserve_vram_fini(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)

---

fr fr, go read amdgpu_ttm.c if you want the full lore. this page is the sparknotes and the sparknotes are cute. 🦋

---

okay that's the whole page!! huge thanks to the /drivers/gpu/drm/amd/amdgpu directory for hosting all this, and a very October 2026 coded shoutout to the amdgpu_ttm_a...mio_remap_bo(9) header+footer combo that got truncated in the middle and honestly? relatable. she's giving main character energy with a name too long for the terminal 💀👑💜