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| author | Mel Henning <mhenning@darkrefraction.com> | 2026-02-19 15:05:54 -0500 |
|---|---|---|
| committer | Danilo Krummrich <dakr@kernel.org> | 2026-02-24 15:04:55 +0100 |
| commit | 196b2b95fec447c2c4460f753b277d840633fbef (patch) | |
| tree | 60eab05ef026516a6992de80e0eff3c3659e8825 /drivers/gpu | |
| parent | 27e125e5568ae4185ffd97abe5b7851ce4f67fe5 (diff) | |
| download | linux-196b2b95fec447c2c4460f753b277d840633fbef.tar.gz linux-196b2b95fec447c2c4460f753b277d840633fbef.zip | |
drm/nouveau: Add DRM_IOCTL_NOUVEAU_GET_ZCULL_INFO
Add kernel-side support for using the zcull hardware in nvidia gpus.
zcull aims to improve memory bandwidth by using an early approximate
depth test, similar to hierarchical Z on an AMD card.
Add a new ioctl that exposes zcull information that has been read
from the hardware. Userspace uses each of these parameters either
in a heuristic for determining zcull region parameters or in the
calculation of a buffer size.
It appears the hardware hasn't changed its structure for these
values since FERMI_C (circa 2011), so the assumption is that it
won't change on us too quickly, and is therefore reasonable to
include in UAPI.
This bypasses the nvif layer and instead accesses nvkm_gr directly,
which mirrors existing usage of nvkm_gr_units(). There is no nvif
object for nvkm_gr yet, and adding one is not trivial.
Signed-off-by: Mel Henning <mhenning@darkrefraction.com>
Link: https://patch.msgid.link/20260219-zcull3-v3-2-dbe6a716f104@darkrefraction.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/nouveau/nouveau_abi16.c | 29 | ||||
| -rw-r--r-- | drivers/gpu/drm/nouveau/nouveau_abi16.h | 1 | ||||
| -rw-r--r-- | drivers/gpu/drm/nouveau/nouveau_drm.c | 1 |
3 files changed, 31 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nouveau_abi16.c b/drivers/gpu/drm/nouveau/nouveau_abi16.c index f9201f2e73a3..7860877d909b 100644 --- a/drivers/gpu/drm/nouveau/nouveau_abi16.c +++ b/drivers/gpu/drm/nouveau/nouveau_abi16.c @@ -334,6 +334,35 @@ nouveau_abi16_ioctl_getparam(ABI16_IOCTL_ARGS) } int +nouveau_abi16_ioctl_get_zcull_info(ABI16_IOCTL_ARGS) +{ + struct nouveau_drm *drm = nouveau_drm(dev); + struct nvkm_gr *gr = nvxx_gr(drm); + struct drm_nouveau_get_zcull_info *out = data; + + if (gr->has_zcull_info) { + const struct nvkm_gr_zcull_info *i = &gr->zcull_info; + + out->width_align_pixels = i->width_align_pixels; + out->height_align_pixels = i->height_align_pixels; + out->pixel_squares_by_aliquots = i->pixel_squares_by_aliquots; + out->aliquot_total = i->aliquot_total; + out->zcull_region_byte_multiplier = i->zcull_region_byte_multiplier; + out->zcull_region_header_size = i->zcull_region_header_size; + out->zcull_subregion_header_size = i->zcull_subregion_header_size; + out->subregion_count = i->subregion_count; + out->subregion_width_align_pixels = i->subregion_width_align_pixels; + out->subregion_height_align_pixels = i->subregion_height_align_pixels; + out->ctxsw_size = i->ctxsw_size; + out->ctxsw_align = i->ctxsw_align; + + return 0; + } else { + return -ENOTTY; + } +} + +int nouveau_abi16_ioctl_channel_alloc(ABI16_IOCTL_ARGS) { struct drm_nouveau_channel_alloc *init = data; diff --git a/drivers/gpu/drm/nouveau/nouveau_abi16.h b/drivers/gpu/drm/nouveau/nouveau_abi16.h index af6b4e1cefd2..134b3ab58719 100644 --- a/drivers/gpu/drm/nouveau/nouveau_abi16.h +++ b/drivers/gpu/drm/nouveau/nouveau_abi16.h @@ -6,6 +6,7 @@ struct drm_device *dev, void *data, struct drm_file *file_priv int nouveau_abi16_ioctl_getparam(ABI16_IOCTL_ARGS); +int nouveau_abi16_ioctl_get_zcull_info(ABI16_IOCTL_ARGS); int nouveau_abi16_ioctl_channel_alloc(ABI16_IOCTL_ARGS); int nouveau_abi16_ioctl_channel_free(ABI16_IOCTL_ARGS); int nouveau_abi16_ioctl_grobj_alloc(ABI16_IOCTL_ARGS); diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c index 17c114645d9f..5d8475e4895e 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drm.c +++ b/drivers/gpu/drm/nouveau/nouveau_drm.c @@ -1304,6 +1304,7 @@ nouveau_ioctls[] = { DRM_IOCTL_DEF_DRV(NOUVEAU_GROBJ_ALLOC, nouveau_abi16_ioctl_grobj_alloc, DRM_RENDER_ALLOW), DRM_IOCTL_DEF_DRV(NOUVEAU_NOTIFIEROBJ_ALLOC, nouveau_abi16_ioctl_notifierobj_alloc, DRM_RENDER_ALLOW), DRM_IOCTL_DEF_DRV(NOUVEAU_GPUOBJ_FREE, nouveau_abi16_ioctl_gpuobj_free, DRM_RENDER_ALLOW), + DRM_IOCTL_DEF_DRV(NOUVEAU_GET_ZCULL_INFO, nouveau_abi16_ioctl_get_zcull_info, DRM_RENDER_ALLOW), DRM_IOCTL_DEF_DRV(NOUVEAU_SVM_INIT, nouveau_svmm_init, DRM_RENDER_ALLOW), DRM_IOCTL_DEF_DRV(NOUVEAU_SVM_BIND, nouveau_svmm_bind, DRM_RENDER_ALLOW), DRM_IOCTL_DEF_DRV(NOUVEAU_GEM_NEW, nouveau_gem_ioctl_new, DRM_RENDER_ALLOW), |