On Mon, Aug 24, 2026 at 6:20 PM Alex Deucher <[email protected]> wrote: > > GMC 9-12 use KIQ or MES for TLB invalidations to avoid using MMIO which would > require disallowing GFXOFF. KIQ and MES are management queues however and if > they hang, they cannot be recovered by a queue reset since they are the > mechanisms which handle queue resets. Since using KIQ or MES will exit GFXOFF > anyway, explicitly disallow it on the MMIO path and use that. Next, switch to > using SDMA for TLB invalidations. SDMA 4.4.x and newer have special packets > specifically for this purpose. If SDMA hangs while doing the invalidation for > some reason, it's easier to reset the SDMA queue than KIQ or MES. Finally, > most of the TLB invalidation code between GMC 9 through 12 was identical, so > move it to common GMC helpers and remove the IP specific code. If the SMDA > and MMIO pathes prove to be stable, the KIQ pathes can be removed in the > future > to further simplify things. SDMA 4.x could also be updated to support PASID > invalidation via SDMA using either the new packet (SDMA 4.4.x) or via > REG_WRITE/REG_WAIT packets (SDMA 4.0.x).
Some older gfxhubs and mmhubs will also need this patch: https://gitlab.freedesktop.org/agd5f/linux/-/commit/a1f1823a8ecd80bee660244def5f20179926fe8c Updated patches with that included here: https://gitlab.freedesktop.org/agd5f/linux/-/commits/tlb_inv_rework?ref_type=heads Alex > > > Alex Deucher (30): > drm/amdgpu/gmc9: disallow gfxoff around TLB flushes > drm/amdgpu/gmc10: disallow gfxoff around TLB flushes > drm/amdgpu/gmc11: disallow gfxoff around TLB flushes > drm/amdgpu/gmc12: disallow gfxoff around TLB flushes > drm/amdgpu: add a gmc flag for using MMIO for TLB flush > drm/amdgpu/gmc9: use MMIO for TLB flushes > drm/amdgpu/gmc10: use MMIO for TLB flushes > drm/amdgpu/gmc11: use MMIO for TLB flushes > drm/amdgpu/gmc12: use MMIO for TLB flushes > drm/amdgpu: add a buffer funcs callback for TLB invalidation > drm/amdgpu/sdma5.0: add tlb invalidation buffer func callback > drm/amdgpu/sdma5.2: add tlb invalidation buffer func callback > drm/amdgpu/sdma6: add tlb invalidation buffer func callback > drm/amdgpu/sdma7: add tlb invalidation buffer func callback > drm/amdgpu: simplify amdgpu_gmc_flush_gpu_tlb() > drm/amdgpu: add tlb invalidation method enum > drm/amdgpu: plumb tlb inv method in amdgpu_gmc_flush_gpu_tlb_gart() > drm/amdgpu: uplevel reset check in amdgpu_gmc_flush_gpu_tlb_gart() > drm/amdgpu/gmc: add new callback to lookup vmid to pasid mapping > drm/amdgpu: add a gmc callback for the inv semaphore > drm/amdgpu/gmc: rework pasid flushing > drm/amdgpu/gmc9: use SDMA for gart TLB invalidation > drm/amdgpu/gmc10: use SDMA for gart TLB invalidation > drm/amdgpu/gmc11: use SDMA for gart TLB invalidation > drm/amdgpu/gmc12: use SDMA for gart TLB invalidation > drm/amdgpu/gmc10: use SDMA for pasid TLB invalidation > drm/amdgpu/gmc11: use SDMA for pasid TLB invalidation > drm/amdgpu/gmc12: use MES or SDMA for pasid TLB invalidation > drm/amdgpu/gmc12: drop MES tlb inv in gmc callbacks > drm/amdgpu/gmc: add helpers for various tlb inv functions > > drivers/gpu/drm/amd/amdgpu/amdgpu_gart.c | 2 +- > drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c | 486 +++++++++++++++++++---- > drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.h | 33 +- > drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.h | 18 + > drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c | 2 + > drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c | 202 +--------- > drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c | 207 +--------- > drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c | 250 ++---------- > drivers/gpu/drm/amd/amdgpu/gmc_v12_1.c | 225 +---------- > drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c | 114 +----- > drivers/gpu/drm/amd/amdgpu/mes_v12_0.c | 4 + > drivers/gpu/drm/amd/amdgpu/mes_v12_1.c | 4 + > drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c | 49 +++ > drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c | 49 +++ > drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c | 49 +++ > drivers/gpu/drm/amd/amdgpu/sdma_v7_0.c | 48 +++ > 16 files changed, 747 insertions(+), 995 deletions(-) > > -- > 2.55.0 >
