[PATCH v6 0/5] Refactor default device atomic settings

[Nirmoy Das]

Merged to drm-xe-next

On 4/30/2024 6:25 PM, Nirmoy Das wrote:
> The default behavior of device atomics depends on the
> VM type and buffer allocation types. Device atomics are
> expected to function with all types of allocations for
> traditional applications/APIs. Additionally, in compute/SVM
> API scenarios with fault mode or LR mode VMs, device atomics
> must work with single-region allocations. In all other cases
> device atomics should be disabled by default. PVC needs special
> care as it doesn't support device atomics on SMEM.
>
> v6: Only check LR mode to determine compute API as fault
>      mode requires LR mode(Jose)
>      Set AE=1 on SMEM+LMEM allocation when a buffer is migrated
>      to LMEM from SMEM(Brian)
>
> v5: Fix broken atomics on PVC from v4 changes.
>
> v4: Previous assumption that device atomics should be disabled
>      by default on SMEM only BO was wrong as traditional applications
>      will not use such allocations for CPU atomics. So remove the
>      VM bind flag and the query uAPI and instead refactor default device
>      atomics settings as per VM type and buffer allocations.
>
>
> v3: Capture ret value of xe_vm_bind_ioctl_validate_bo(Matt B).
>      Remove redundant coh_mode param from xe_vm_bind_ioctl_validate_bo().
>      Remove has_device_atomics_on_smem from xe_graphics_desc(Jose).
>      Replace DRM_XE_QUERY_CONFIG_SUPP_DEV_ATOMIC_ON_SMEM with
>      config flag DRM_XE_QUERY_CONFIG_FLAG_HAS_DEV_ATOMIC_ON_SMEM(Jose).
>      Mention that PTE_AE will not be applied to userptr(Matt R)
>
> v2: Add BO helper func in xe_vm_bind_ioctl()(Matt B).
>      Use XE_IOCTL_DBG for checks(Matt B).
>      Move platform checks with help of adding flags in
>      intel_device_info(Matt B).
>      Add document for DRM_XE_VM_BIND_FLAG_DEVICE_ATOMICS(Matt B).
>      Create query uAPI for this newly added VM bind flag(Jose, Lionel).
>
> Cc: Balasubramani Vivekanandan <balasubramani.vivekanandan at intel.com>
> Cc: Brian Welty <brian.welty at intel.com>
> Cc: Fei Yang <fei.yang at intel.com>
> Cc: Jose Souza <jose.souza at intel.com>
> Cc: Lionel G Landwerlin <lionel.g.landwerlin at intel.com>
> Cc: Matt Roper <matthew.d.roper at intel.com>
> Cc: Matthew Brost <matthew.brost at intel.com>
> Cc: Michal Mrozek <michal.mrozek at intel.com>
> Cc: Oak Zeng <oak.zeng at intel.com>
> Cc: Thomas Hellstr_m <thomas.hellstrom at linux.intel.com>
>
> Nirmoy Das (5):
>    drm/xe: Introduce has_atomic_enable_pte_bit device info
>    drm/xe: Move vm bind bo validation to a helper function
>    drm/xe: Introduce has_device_atomics_on_smem device info
>    drm/xe: Add function to check if BO has single placement
>    drm/xe: Refactor default device atomic settings
>
>   drivers/gpu/drm/xe/xe_bo.c           | 14 +++++
>   drivers/gpu/drm/xe/xe_bo.h           |  1 +
>   drivers/gpu/drm/xe/xe_device_types.h |  4 ++
>   drivers/gpu/drm/xe/xe_pci.c          |  5 ++
>   drivers/gpu/drm/xe/xe_pci_types.h    |  1 +
>   drivers/gpu/drm/xe/xe_pt.c           | 37 +++++++++++--
>   drivers/gpu/drm/xe/xe_vm.c           | 79 ++++++++++++++++------------
>   7 files changed, 103 insertions(+), 38 deletions(-)
>