diff options
| author | Rob Clark <robdclark@chromium.org> | 2025-06-29 13:13:05 -0700 |
|---|---|---|
| committer | Rob Clark <robin.clark@oss.qualcomm.com> | 2025-07-04 17:48:36 -0700 |
| commit | feb8ef4636a457a1fd916a3ae575f552935e69b9 (patch) | |
| tree | e8a5ad9c03613d716cc68aba1d6bad6ef2db316a /include/uapi | |
| parent | drm/msm: Lazily create context VM (diff) | |
| download | linux-feb8ef4636a457a1fd916a3ae575f552935e69b9.tar.gz linux-feb8ef4636a457a1fd916a3ae575f552935e69b9.zip | |
drm/msm: Add opt-in for VM_BIND
Add a SET_PARAM for userspace to request to manage to the VM itself,
instead of getting a kernel managed VM.
In order to transition to a userspace managed VM, this param must be set
before any mappings are created.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>
Tested-by: Antonino Maniscalco <antomani103@gmail.com>
Reviewed-by: Antonino Maniscalco <antomani103@gmail.com>
Patchwork: https://patchwork.freedesktop.org/patch/661494/
Diffstat (limited to 'include/uapi')
| -rw-r--r-- | include/uapi/drm/msm_drm.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/include/uapi/drm/msm_drm.h b/include/uapi/drm/msm_drm.h index 5bc5e4526ccf..b974f5a24dbc 100644 --- a/include/uapi/drm/msm_drm.h +++ b/include/uapi/drm/msm_drm.h @@ -93,6 +93,30 @@ struct drm_msm_timespec { #define MSM_PARAM_UCHE_TRAP_BASE 0x14 /* RO */ /* PRR (Partially Resident Region) is required for sparse residency: */ #define MSM_PARAM_HAS_PRR 0x15 /* RO */ +/* MSM_PARAM_EN_VM_BIND is set to 1 to enable VM_BIND ops. + * + * With VM_BIND enabled, userspace is required to allocate iova and use the + * VM_BIND ops for map/unmap ioctls. MSM_INFO_SET_IOVA and MSM_INFO_GET_IOVA + * will be rejected. (The latter does not have a sensible meaning when a BO + * can have multiple and/or partial mappings.) + * + * With VM_BIND enabled, userspace does not include a submit_bo table in the + * SUBMIT ioctl (this will be rejected), the resident set is determined by + * the the VM_BIND ops. + * + * Enabling VM_BIND will fail on devices which do not have per-process pgtables. + * And it is not allowed to disable VM_BIND once it has been enabled. + * + * Enabling VM_BIND should be done (attempted) prior to allocating any BOs or + * submitqueues of type MSM_SUBMITQUEUE_VM_BIND. + * + * Relatedly, when VM_BIND mode is enabled, the kernel will not try to recover + * from GPU faults or failed async VM_BIND ops, in particular because it is + * difficult to communicate to userspace which op failed so that userspace + * could rewind and try again. When the VM is marked unusable, the SUBMIT + * ioctl will throw -EPIPE. + */ +#define MSM_PARAM_EN_VM_BIND 0x16 /* WO, once */ /* For backwards compat. The original support for preemption was based on * a single ring per priority level so # of priority levels equals the # |