[PATCH 0/9] accel: New driver for NXP's Neutron NPU

[Ioana Ciocoi-Radulescu <ruxandra.radulescu@nxp.com>]

Introduce a new accel driver for the Neutron Neural Processing Unit
(NPU), along with associated dt-bindings and DTS node.

The first patch extends the GEM DMA helper APIs to allow bidirectional
mapping of non-coherent DMA buffers. While not part of the Neutron
driver, it's a prerequisite allowing us to use the GEM DMA helper.

Neutron is a Neural Processing Unit from NXP, providing machine
learning (ML) acceleration for edge AI applications. Neutron is
integrated on NXP SoCs such as the i.MX95.

The NPU consists of the following:
- RISC-V core running a proprietary firmware
- One or more Neutron cores, representing the main computation
  engine performing ML operations
- Dedicated fast memory (TCM)
- DMA engine that handles data transfers between DDR and TCM

The firmware is closed source and distributed as a binary here [1].

The Neutron software stack also contains a userspace library [1] and
a LiteRT custom delegate [2] that allow integration with standard
LiteRT tools.

[1] https://github.com/nxp-upstream/neutron/tree/upstream
[2] https://github.com/nxp-imx/tflite-neutron-delegate

Signed-off-by: Ioana Ciocoi-Radulescu <ruxandra.radulescu@nxp.com>
---
Ioana Ciocoi-Radulescu (9):
      drm/gem-dma: Add flag for bidirectional mapping of non-coherent GEM DMA buffers
      accel/neutron: Add documentation for NXP Neutron accelerator driver
      dt-bindings: npu: Add bindings for NXP Neutron
      accel/neutron: Add driver for NXP Neutron NPU
      accel/neutron: Add GEM buffer object support
      accel/neutron: Add mailbox support
      accel/neutron: Add job submission IOCTL
      accel/neutron: Add logging support
      arm64: dts: imx95: Add Neutron node

 Documentation/accel/index.rst                      |   1 +
 Documentation/accel/neutron/index.rst              |  12 +
 Documentation/accel/neutron/neutron.rst            | 131 ++++++++
 .../devicetree/bindings/npu/nxp,imx95-neutron.yaml |  95 ++++++
 MAINTAINERS                                        |  10 +
 arch/arm64/boot/dts/freescale/imx95.dtsi           |  28 ++
 drivers/accel/Kconfig                              |   1 +
 drivers/accel/Makefile                             |   3 +-
 drivers/accel/neutron/Kconfig                      |  16 +
 drivers/accel/neutron/Makefile                     |  12 +
 drivers/accel/neutron/neutron_debugfs.c            |  34 ++
 drivers/accel/neutron/neutron_debugfs.h            |  15 +
 drivers/accel/neutron/neutron_device.c             | 239 ++++++++++++++
 drivers/accel/neutron/neutron_device.h             | 158 +++++++++
 drivers/accel/neutron/neutron_driver.c             | 262 +++++++++++++++
 drivers/accel/neutron/neutron_driver.h             |  16 +
 drivers/accel/neutron/neutron_gem.c                | 115 +++++++
 drivers/accel/neutron/neutron_gem.h                |  14 +
 drivers/accel/neutron/neutron_job.c                | 367 +++++++++++++++++++++
 drivers/accel/neutron/neutron_job.h                |  45 +++
 drivers/accel/neutron/neutron_mailbox.c            |  47 +++
 drivers/accel/neutron/neutron_mailbox.h            |  42 +++
 drivers/gpu/drm/drm_gem_dma_helper.c               |   6 +-
 include/drm/drm_gem_dma_helper.h                   |   3 +
 include/uapi/drm/neutron_accel.h                   | 130 ++++++++
 25 files changed, 1799 insertions(+), 3 deletions(-)
---
base-commit: 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f
change-id: 20260226-neutron-c435e39d167f

Best regards,
-- 
Ioana Ciocoi-Radulescu <ruxandra.radulescu@nxp.com>