From cdeaeb9dd762d7711241a62459dfb730b2cd0281 Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Thu, 24 Apr 2025 18:02:50 +0200 Subject: drm: nova-drm: add initial driver skeleton Add the initial nova-drm driver skeleton. nova-drm is connected to nova-core through the auxiliary bus and implements the DRM parts of the nova driver stack. For now, it implements the fundamental DRM abstractions, i.e. creates a DRM device and registers it, exposing a three sample IOCTLs. DRM_IOCTL_NOVA_GETPARAM - provides the PCI bar size from the bar that maps the GPUs VRAM from nova-core DRM_IOCTL_NOVA_GEM_CREATE - creates a new dummy DRM GEM object and returns a handle DRM_IOCTL_NOVA_GEM_INFO - provides metadata for the DRM GEM object behind a given handle I implemented a small userspace test suite [1] that utilizes this interface. Link: https://gitlab.freedesktop.org/dakr/drm-test [1] Reviewed-by: Maxime Ripard Acked-by: Dave Airlie Link: https://lore.kernel.org/r/20250424160452.8070-3-dakr@kernel.org [ Kconfig: depend on DRM=y rather than just DRM. - Danilo ] Signed-off-by: Danilo Krummrich --- include/uapi/drm/nova_drm.h | 101 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 include/uapi/drm/nova_drm.h (limited to 'include/uapi') diff --git a/include/uapi/drm/nova_drm.h b/include/uapi/drm/nova_drm.h new file mode 100644 index 000000000000..3ca90ed9d2bb --- /dev/null +++ b/include/uapi/drm/nova_drm.h @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: MIT */ + +#ifndef __NOVA_DRM_H__ +#define __NOVA_DRM_H__ + +#include "drm.h" + +/* DISCLAIMER: Do not use, this is not a stable uAPI. + * + * This uAPI serves only testing purposes as long as this driver is still in + * development. It is required to implement and test infrastructure which is + * upstreamed in the context of this driver. See also [1]. + * + * [1] https://lore.kernel.org/dri-devel/Zfsj0_tb-0-tNrJy@cassiopeiae/T/#u + */ + +#if defined(__cplusplus) +extern "C" { +#endif + +/* + * NOVA_GETPARAM_VRAM_BAR_SIZE + * + * Query the VRAM BAR size in bytes. + */ +#define NOVA_GETPARAM_VRAM_BAR_SIZE 0x1 + +/** + * struct drm_nova_getparam - query GPU and driver metadata + */ +struct drm_nova_getparam { + /** + * @param: The identifier of the parameter to query. + */ + __u64 param; + + /** + * @value: The value for the specified parameter. + */ + __u64 value; +}; + +/** + * struct drm_nova_gem_create - create a new DRM GEM object + */ +struct drm_nova_gem_create { + /** + * @handle: The handle of the new DRM GEM object. + */ + __u32 handle; + + /** + * @pad: 32 bit padding, should be 0. + */ + __u32 pad; + + /** + * @size: The size of the new DRM GEM object. + */ + __u64 size; +}; + +/** + * struct drm_nova_gem_info - query DRM GEM object metadata + */ +struct drm_nova_gem_info { + /** + * @handle: The handle of the DRM GEM object to query. + */ + __u32 handle; + + /** + * @pad: 32 bit padding, should be 0. + */ + __u32 pad; + + /** + * @size: The size of the DRM GEM obejct. + */ + __u64 size; +}; + +#define DRM_NOVA_GETPARAM 0x00 +#define DRM_NOVA_GEM_CREATE 0x01 +#define DRM_NOVA_GEM_INFO 0x02 + +/* Note: this is an enum so that it can be resolved by Rust bindgen. */ +enum { + DRM_IOCTL_NOVA_GETPARAM = DRM_IOWR(DRM_COMMAND_BASE + DRM_NOVA_GETPARAM, + struct drm_nova_getparam), + DRM_IOCTL_NOVA_GEM_CREATE = DRM_IOWR(DRM_COMMAND_BASE + DRM_NOVA_GEM_CREATE, + struct drm_nova_gem_create), + DRM_IOCTL_NOVA_GEM_INFO = DRM_IOWR(DRM_COMMAND_BASE + DRM_NOVA_GEM_INFO, + struct drm_nova_gem_info), +}; + +#if defined(__cplusplus) +} +#endif + +#endif /* __NOVA_DRM_H__ */ -- cgit v1.2.3