Hi Tomeu,

Am Dienstag, dem 20.05.2025 um 12:27 +0200 schrieb Tomeu Vizoso:

The NPU cores have their own access to the memory bus, and this isn't cache coherent with the CPUs.

Add IOCTLs so userspace can mark when the caches need to be flushed, and also when a writer job needs to be waited for before the buffer can be accessed from the CPU.

Initially based on the same IOCTLs from the Etnaviv driver.

v2:

• Don't break UABI by reordering the IOCTL IDs (Jeff Hugo)

v3:

• Check that padding fields in IOCTLs are zero (Jeff Hugo)

Signed-off-by: Tomeu Vizoso tomeu@tomeuvizoso.net

drivers/accel/rocket/rocket_drv.c | 2 + drivers/accel/rocket/rocket_gem.c | 80 +++++++++++++++++++++++++++++++++++++++ drivers/accel/rocket/rocket_gem.h | 5 +++ include/uapi/drm/rocket_accel.h | 37 ++++++++++++++++++ 4 files changed, 124 insertions(+)

diff --git a/drivers/accel/rocket/rocket_drv.c b/drivers/accel/rocket/rocket_drv.c index fef9b93372d3f65c41c1ac35a9bfa0c01ee721a5..c06e66939e6c39909fe08bef3c4f301b07bf8fbf 100644 --- a/drivers/accel/rocket/rocket_drv.c +++ b/drivers/accel/rocket/rocket_drv.c @@ -59,6 +59,8 @@ static const struct drm_ioctl_desc rocket_drm_driver_ioctls[] = { ROCKET_IOCTL(CREATE_BO, create_bo), ROCKET_IOCTL(SUBMIT, submit),

• ROCKET_IOCTL(PREP_BO, prep_bo),
• ROCKET_IOCTL(FINI_BO, fini_bo),

}; DEFINE_DRM_ACCEL_FOPS(rocket_accel_driver_fops); diff --git a/drivers/accel/rocket/rocket_gem.c b/drivers/accel/rocket/rocket_gem.c index 8a8a7185daac4740081293aae6945c9b2bbeb2dd..cdc5238a93fa5978129dc1ac8ec8de955160dc18 100644 --- a/drivers/accel/rocket/rocket_gem.c +++ b/drivers/accel/rocket/rocket_gem.c @@ -129,3 +129,83 @@ int rocket_ioctl_create_bo(struct drm_device *dev, void *data, struct drm_file * return ret; }

+static inline enum dma_data_direction rocket_op_to_dma_dir(u32 op) +{

• if (op & ROCKET_PREP_READ)

• return DMA_FROM_DEVICE;
  

• else if (op & ROCKET_PREP_WRITE)

• return DMA_TO_DEVICE;
  

• else

• return DMA_BIDIRECTIONAL;
  

+}

This has copied over the bug fixed in etnaviv commit 58979ad6330a ("drm/etnaviv: fix DMA direction handling for cached RW buffers")

Regards, Lucas