On 14/05/2022 00:06, Jordan Justen wrote:
On 2022-05-13 05:31:00, Lionel Landwerlin wrote:
On 02/05/2022 17:15, Ramalingam C wrote:
Capture the impact of memory region preference list of the objects, on their memory residency and Flat-CCS capability.
v2: Fix the Flat-CCS capability of an obj with {lmem, smem} preference list [Thomas] v3: Reworded the doc [Matt]
Signed-off-by: Ramalingam Cramalingam.c@intel.com cc: Matthew Auldmatthew.auld@intel.com cc: Thomas Hellstromthomas.hellstrom@linux.intel.com cc: Daniel Vetterdaniel.vetter@ffwll.ch cc: Jon Bloomfieldjon.bloomfield@intel.com cc: Lionel Landwerlinlionel.g.landwerlin@intel.com cc: Kenneth Graunkekenneth@whitecape.org cc:mesa-dev@lists.freedesktop.org cc: Jordan Justenjordan.l.justen@intel.com cc: Tony Yetony.ye@intel.com Reviewed-by: Matthew Auldmatthew.auld@intel.com
include/uapi/drm/i915_drm.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h index a2def7b27009..b7e1c2fe08dc 100644 --- a/include/uapi/drm/i915_drm.h +++ b/include/uapi/drm/i915_drm.h @@ -3443,6 +3443,22 @@ struct drm_i915_gem_create_ext { * At which point we get the object handle in &drm_i915_gem_create_ext.handle, * along with the final object size in &drm_i915_gem_create_ext.size, which * should account for any rounding up, if required.
- Note that userspace has no means of knowing the current backing region
- for objects where @num_regions is larger than one. The kernel will only
- ensure that the priority order of the @regions array is honoured, either
- when initially placing the object, or when moving memory around due to
- memory pressure
- On Flat-CCS capable HW, compression is supported for the objects residing
- in I915_MEMORY_CLASS_DEVICE. When such objects (compressed) has other
- memory class in @regions and migrated (by I915, due to memory
- constrain) to the non I915_MEMORY_CLASS_DEVICE region, then I915 needs to
- decompress the content. But I915 dosen't have the required information to
- decompress the userspace compressed objects.
- So I915 supports Flat-CCS, only on the objects which can reside only on
- I915_MEMORY_CLASS_DEVICE regions.
I think it's fine to assume Flat-CSS surface will always be in lmem.
I see no issue for the Anv Vulkan driver.
Maybe Nanley or Ken can speak for the Iris GL driver?
Acked-by: Jordan Justenjordan.l.justen@intel.com
I think Nanley has accounted for this on iris with:
https://gitlab.freedesktop.org/mesa/mesa/-/commit/42a865730ef72574e179b56a31...
-Jordan
Thanks Jordan,
We might want to through in an additional : assert((|flags &||BO_ALLOC_SMEM) == 0); in the CCS case |
| |
|-Lionel |