drm/panfrost, panthor: Cached maps and explicit flushing

From:		Boris Brezillon <boris.brezillon-AT-collabora.com>
To:		Steven Price <steven.price-AT-arm.com>
Subject:		[PATCH v4 00/14] drm/panfrost, panthor: Cached maps and explicit flushing
Date:		Wed, 15 Oct 2025 18:03:12 +0200
Message-ID:		<20251015160326.3657287-1-boris.brezillon@collabora.com>
Cc:		dri-devel-AT-lists.freedesktop.org, Maarten Lankhorst <maarten.lankhorst-AT-linux.intel.com>, Maxime Ripard <mripard-AT-kernel.org>, Thomas Zimmermann <tzimmermann-AT-suse.de>, David Airlie <airlied-AT-gmail.com>, Simona Vetter <simona-AT-ffwll.ch>, Faith Ekstrand <faith.ekstrand-AT-collabora.com>, Boris Brezillon <boris.brezillon-AT-collabora.com>, kernel-AT-collabora.com
Archive-link:		Article

This series implements cached maps and explicit flushing for both panfrost
and panthor.  To avoid code/bug duplication, the tricky guts of the cache
flushing ioctl which walk the sg list are broken into a new common shmem
helper which can be used by any driver.

The PanVK MR to use this lives here:

https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests...

Changes in v2:
- Expose the coherency so userspace can know when it should skip cache
  maintenance
- Hook things up at drm_gem_object_funcs level to dma-buf cpu_prep hooks
  can be implemented generically
- Revisit the semantics of the flags passed to gem_sync()
- Add BO_QUERY_INFO ioctls to query BO flags on imported objects and
  let the UMD know when cache maintenance is needed on those

Changes in v3:
- New patch to fix panthor_gpu_coherency_set()
- No other major changes, check each patch changelog for more details

Changes in v4:
- Two trivial fixes, check each patch changelog for more details

Boris Brezillon (7):
  drm/panthor: Fix panthor_gpu_coherency_set()
  drm/gem: Add a drm_gem_object_funcs::sync() and a drm_gem_sync()
    helper
  drm/prime: Provide default ::{begin,end}_cpu_access() implementations
  drm/panthor: Expose the selected coherency protocol to the UMD
  drm/panthor: Add an ioctl to query BO flags
  drm/panfrost: Expose the selected coherency protocol to the UMD
  drm/panfrost: Add an ioctl to query BO flags

Faith Ekstrand (6):
  drm/shmem: Add a drm_gem_shmem_sync() helper
  drm/panthor: Add a PANTHOR_BO_SYNC ioctl
  drm/panthor: Bump the driver version to 1.6
  drm/panfrost: Add a PANFROST_SYNC_BO ioctl
  drm/panfrost: Add flag to map GEM object Write-Back Cacheable
  drm/panfrost: Bump the driver version to 1.6

Loïc Molinari (1):
  drm/panthor: Add flag to map GEM object Write-Back Cacheable

 drivers/gpu/drm/drm_gem.c                  |  10 ++
 drivers/gpu/drm/drm_gem_shmem_helper.c     |  89 +++++++++++
 drivers/gpu/drm/drm_prime.c                |  42 +++++
 drivers/gpu/drm/panfrost/panfrost_device.h |   1 +
 drivers/gpu/drm/panfrost/panfrost_drv.c    | 106 ++++++++++++-
 drivers/gpu/drm/panfrost/panfrost_gem.c    |  23 +++
 drivers/gpu/drm/panfrost/panfrost_gem.h    |   2 +
 drivers/gpu/drm/panfrost/panfrost_gpu.c    |  26 +++-
 drivers/gpu/drm/panfrost/panfrost_regs.h   |  10 +-
 drivers/gpu/drm/panthor/panthor_device.c   |  10 +-
 drivers/gpu/drm/panthor/panthor_drv.c      |  84 +++++++++-
 drivers/gpu/drm/panthor/panthor_gem.c      |  24 +++
 drivers/gpu/drm/panthor/panthor_gem.h      |   3 +
 drivers/gpu/drm/panthor/panthor_gpu.c      |   2 +-
 drivers/gpu/drm/panthor/panthor_sched.c    |  18 ++-
 include/drm/drm_gem.h                      |  45 ++++++
 include/drm/drm_gem_shmem_helper.h         |  11 ++
 include/drm/drm_prime.h                    |   5 +
 include/uapi/drm/panfrost_drm.h            |  74 +++++++++
 include/uapi/drm/panthor_drm.h             | 171 ++++++++++++++++++++-
 20 files changed, 738 insertions(+), 18 deletions(-)

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2.51.0