Merge tag 'nova-next-v6.16-2025-05-20' of https://gitlab.freedesktop.org/drm/nova into drm-next

Nova changes for v6.16

auxiliary:
  - bus abstractions
  - implementation for driver registration
  - add sample driver

drm:
  - implement __drm_dev_alloc()
  - DRM core infrastructure Rust abstractions
    - device, driver and registration
    - DRM IOCTL
    - DRM File
    - GEM object
  - IntoGEMObject rework
    - generically implement AlwaysRefCounted through IntoGEMObject
    - refactor unsound from_gem_obj() into as_ref()
    - refactor into_gem_obj() into as_raw()

driver-core:
  - merge topic/device-context-2025-04-17 from driver-core tree
  - implement Devres::access()
    - fix: doctest build under `!CONFIG_PCI`
  - accessor for Device::parent()
    - fix: conditionally expect `dead_code` for `parent()`
  - impl TryFrom<&Device> bus devices (PCI, platform)

nova-core:
  - remove completed Vec extentions from task list
  - register auxiliary device for nova-drm
  - derive useful traits for Chipset
  - add missing GA100 chipset
  - take &Device<Bound> in Gpu::new()
  - infrastructure to generate register definitions
  - fix register layout of NV_PMC_BOOT_0
  - move Firmware into own (Rust) module
  - fix: select AUXILIARY_BUS

nova-drm:
  - initial driver skeleton (depends on drm and auxiliary bus
    abstractions)
  - fix: select AUXILIARY_BUS

Rust (dependencies):
  - implement Opaque::zeroed()
  - implement Revocable::try_access_with()
  - implement Revocable::access()

From: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/aCxAf3RqQAXLDhAj@cassiopeiae

10 files changed, 333 insertions, 16 deletions

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index 9488fc01bca3..f094797f3b2b 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -274,6 +274,8 @@ source "drivers/gpu/drm/amd/amdgpu/Kconfig"
 
 source "drivers/gpu/drm/nouveau/Kconfig"
 
+source "drivers/gpu/drm/nova/Kconfig"
+
 source "drivers/gpu/drm/i915/Kconfig"
 
 source "drivers/gpu/drm/xe/Kconfig"
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 70510620f29c..4199715670b1 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -177,6 +177,7 @@ obj-$(CONFIG_DRM_VMWGFX)+= vmwgfx/
 obj-$(CONFIG_DRM_VGEM)	+= vgem/
 obj-$(CONFIG_DRM_VKMS)	+= vkms/
 obj-$(CONFIG_DRM_NOUVEAU) +=nouveau/
+obj-$(CONFIG_DRM_NOVA) += nova/
 obj-$(CONFIG_DRM_EXYNOS) +=exynos/
 obj-$(CONFIG_DRM_ROCKCHIP) +=rockchip/
 obj-$(CONFIG_DRM_GMA500) += gma500/
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 3dc7acd56b1d..4589ab4bb1ec 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -830,36 +830,62 @@ void *__devm_drm_dev_alloc(struct device *parent,
 EXPORT_SYMBOL(__devm_drm_dev_alloc);
 
 /**
- * drm_dev_alloc - Allocate new DRM device
- * @driver: DRM driver to allocate device for
+ * __drm_dev_alloc - Allocation of a &drm_device instance
  * @parent: Parent device object
+ * @driver: DRM driver
+ * @size: the size of the struct which contains struct drm_device
+ * @offset: the offset of the &drm_device within the container.
  *
- * This is the deprecated version of devm_drm_dev_alloc(), which does not support
- * subclassing through embedding the struct &drm_device in a driver private
- * structure, and which does not support automatic cleanup through devres.
+ * This should *NOT* be by any drivers, but is a dedicated interface for the
+ * corresponding Rust abstraction.
  *
- * RETURNS:
- * Pointer to new DRM device, or ERR_PTR on failure.
+ * This is the same as devm_drm_dev_alloc(), but without the corresponding
+ * resource management through the parent device, but not the same as
+ * drm_dev_alloc(), since the latter is the deprecated version, which does not
+ * support subclassing.
+ *
+ * Returns: A pointer to new DRM device, or an ERR_PTR on failure.
  */
-struct drm_device *drm_dev_alloc(const struct drm_driver *driver,
-				 struct device *parent)
+void *__drm_dev_alloc(struct device *parent,
+		      const struct drm_driver *driver,
+		      size_t size, size_t offset)
 {
-	struct drm_device *dev;
+	void *container;
+	struct drm_device *drm;
 	int ret;
 
-	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-	if (!dev)
+	container = kzalloc(size, GFP_KERNEL);
+	if (!container)
 		return ERR_PTR(-ENOMEM);
 
-	ret = drm_dev_init(dev, driver, parent);
+	drm = container + offset;
+	ret = drm_dev_init(drm, driver, parent);
 	if (ret) {
-		kfree(dev);
+		kfree(container);
 		return ERR_PTR(ret);
 	}
+	drmm_add_final_kfree(drm, container);
 
-	drmm_add_final_kfree(dev, dev);
+	return container;
+}
+EXPORT_SYMBOL(__drm_dev_alloc);
 
-	return dev;
+/**
+ * drm_dev_alloc - Allocate new DRM device
+ * @driver: DRM driver to allocate device for
+ * @parent: Parent device object
+ *
+ * This is the deprecated version of devm_drm_dev_alloc(), which does not support
+ * subclassing through embedding the struct &drm_device in a driver private
+ * structure, and which does not support automatic cleanup through devres.
+ *
+ * RETURNS:
+ * Pointer to new DRM device, or ERR_PTR on failure.
+ */
+struct drm_device *drm_dev_alloc(const struct drm_driver *driver,
+				 struct device *parent)
+{
+	return __drm_dev_alloc(parent, driver, sizeof(struct drm_device), 0);
 }
 EXPORT_SYMBOL(drm_dev_alloc);
 
diff --git a/drivers/gpu/drm/nova/Kconfig b/drivers/gpu/drm/nova/Kconfig
new file mode 100644
index 000000000000..cca6a3fea879
--- /dev/null
+++ b/drivers/gpu/drm/nova/Kconfig
@@ -0,0 +1,14 @@
+config DRM_NOVA
+	tristate "Nova DRM driver"
+	depends on DRM=y
+	depends on PCI
+	depends on RUST
+	select AUXILIARY_BUS
+	default n
+	help
+	  Choose this if you want to build the Nova DRM driver for Nvidia
+	  GSP-based GPUs.
+
+	  This driver is work in progress and may not be functional.
+
+	  If M is selected, the module will be called nova.
diff --git a/drivers/gpu/drm/nova/Makefile b/drivers/gpu/drm/nova/Makefile
new file mode 100644
index 000000000000..42019bff3173
--- /dev/null
+++ b/drivers/gpu/drm/nova/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_DRM_NOVA) += nova.o
diff --git a/drivers/gpu/drm/nova/driver.rs b/drivers/gpu/drm/nova/driver.rs
new file mode 100644
index 000000000000..b28b2e05cc15
--- /dev/null
+++ b/drivers/gpu/drm/nova/driver.rs
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use kernel::{auxiliary, c_str, device::Core, drm, drm::gem, drm::ioctl, prelude::*, types::ARef};
+
+use crate::file::File;
+use crate::gem::NovaObject;
+
+pub(crate) struct NovaDriver {
+    #[expect(unused)]
+    drm: ARef<drm::Device<Self>>,
+}
+
+/// Convienence type alias for the DRM device type for this driver
+pub(crate) type NovaDevice = drm::Device<NovaDriver>;
+
+#[pin_data]
+pub(crate) struct NovaData {
+    pub(crate) adev: ARef<auxiliary::Device>,
+}
+
+const INFO: drm::DriverInfo = drm::DriverInfo {
+    major: 0,
+    minor: 0,
+    patchlevel: 0,
+    name: c_str!("nova"),
+    desc: c_str!("Nvidia Graphics"),
+};
+
+const NOVA_CORE_MODULE_NAME: &CStr = c_str!("NovaCore");
+const AUXILIARY_NAME: &CStr = c_str!("nova-drm");
+
+kernel::auxiliary_device_table!(
+    AUX_TABLE,
+    MODULE_AUX_TABLE,
+    <NovaDriver as auxiliary::Driver>::IdInfo,
+    [(
+        auxiliary::DeviceId::new(NOVA_CORE_MODULE_NAME, AUXILIARY_NAME),
+        ()
+    )]
+);
+
+impl auxiliary::Driver for NovaDriver {
+    type IdInfo = ();
+    const ID_TABLE: auxiliary::IdTable<Self::IdInfo> = &AUX_TABLE;
+
+    fn probe(adev: &auxiliary::Device<Core>, _info: &Self::IdInfo) -> Result<Pin<KBox<Self>>> {
+        let data = try_pin_init!(NovaData { adev: adev.into() });
+
+        let drm = drm::Device::<Self>::new(adev.as_ref(), data)?;
+        drm::Registration::new_foreign_owned(&drm, adev.as_ref(), 0)?;
+
+        Ok(KBox::new(Self { drm }, GFP_KERNEL)?.into())
+    }
+}
+
+#[vtable]
+impl drm::Driver for NovaDriver {
+    type Data = NovaData;
+    type File = File;
+    type Object = gem::Object<NovaObject>;
+
+    const INFO: drm::DriverInfo = INFO;
+
+    kernel::declare_drm_ioctls! {
+        (NOVA_GETPARAM, drm_nova_getparam, ioctl::RENDER_ALLOW, File::get_param),
+        (NOVA_GEM_CREATE, drm_nova_gem_create, ioctl::AUTH | ioctl::RENDER_ALLOW, File::gem_create),
+        (NOVA_GEM_INFO, drm_nova_gem_info, ioctl::AUTH | ioctl::RENDER_ALLOW, File::gem_info),
+    }
+}
diff --git a/drivers/gpu/drm/nova/file.rs b/drivers/gpu/drm/nova/file.rs
new file mode 100644
index 000000000000..7e59a34b830d
--- /dev/null
+++ b/drivers/gpu/drm/nova/file.rs
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use crate::driver::{NovaDevice, NovaDriver};
+use crate::gem::NovaObject;
+use crate::uapi::{GemCreate, GemInfo, Getparam};
+use kernel::{
+    alloc::flags::*,
+    drm::{self, gem::BaseObject},
+    pci,
+    prelude::*,
+    types::Opaque,
+    uapi,
+};
+
+pub(crate) struct File;
+
+impl drm::file::DriverFile for File {
+    type Driver = NovaDriver;
+
+    fn open(_dev: &NovaDevice) -> Result<Pin<KBox<Self>>> {
+        Ok(KBox::new(Self, GFP_KERNEL)?.into())
+    }
+}
+
+impl File {
+    /// IOCTL: get_param: Query GPU / driver metadata.
+    pub(crate) fn get_param(
+        dev: &NovaDevice,
+        getparam: &Opaque<uapi::drm_nova_getparam>,
+        _file: &drm::File<File>,
+    ) -> Result<u32> {
+        let adev = &dev.adev;
+        let parent = adev.parent().ok_or(ENOENT)?;
+        let pdev: &pci::Device = parent.try_into()?;
+        let getparam: &Getparam = getparam.into();
+
+        let value = match getparam.param() as u32 {
+            uapi::NOVA_GETPARAM_VRAM_BAR_SIZE => pdev.resource_len(1)?,
+            _ => return Err(EINVAL),
+        };
+
+        getparam.set_value(value);
+
+        Ok(0)
+    }
+
+    /// IOCTL: gem_create: Create a new DRM GEM object.
+    pub(crate) fn gem_create(
+        dev: &NovaDevice,
+        req: &Opaque<uapi::drm_nova_gem_create>,
+        file: &drm::File<File>,
+    ) -> Result<u32> {
+        let req: &GemCreate = req.into();
+        let obj = NovaObject::new(dev, req.size().try_into()?)?;
+
+        req.set_handle(obj.create_handle(file)?);
+
+        Ok(0)
+    }
+
+    /// IOCTL: gem_info: Query GEM metadata.
+    pub(crate) fn gem_info(
+        _dev: &NovaDevice,
+        req: &Opaque<uapi::drm_nova_gem_info>,
+        file: &drm::File<File>,
+    ) -> Result<u32> {
+        let req: &GemInfo = req.into();
+        let bo = NovaObject::lookup_handle(file, req.handle())?;
+
+        req.set_size(bo.size().try_into()?);
+
+        Ok(0)
+    }
+}
diff --git a/drivers/gpu/drm/nova/gem.rs b/drivers/gpu/drm/nova/gem.rs
new file mode 100644
index 000000000000..33b62d21400c
--- /dev/null
+++ b/drivers/gpu/drm/nova/gem.rs
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use kernel::{
+    drm,
+    drm::{gem, gem::BaseObject},
+    prelude::*,
+    types::ARef,
+};
+
+use crate::{
+    driver::{NovaDevice, NovaDriver},
+    file::File,
+};
+
+/// GEM Object inner driver data
+#[pin_data]
+pub(crate) struct NovaObject {}
+
+impl gem::BaseDriverObject<gem::Object<NovaObject>> for NovaObject {
+    fn new(_dev: &NovaDevice, _size: usize) -> impl PinInit<Self, Error> {
+        try_pin_init!(NovaObject {})
+    }
+}
+
+impl gem::DriverObject for NovaObject {
+    type Driver = NovaDriver;
+}
+
+impl NovaObject {
+    /// Create a new DRM GEM object.
+    pub(crate) fn new(dev: &NovaDevice, size: usize) -> Result<ARef<gem::Object<Self>>> {
+        let aligned_size = size.next_multiple_of(1 << 12);
+
+        if size == 0 || size > aligned_size {
+            return Err(EINVAL);
+        }
+
+        gem::Object::new(dev, aligned_size)
+    }
+
+    /// Look up a GEM object handle for a `File` and return an `ObjectRef` for it.
+    #[inline]
+    pub(crate) fn lookup_handle(
+        file: &drm::File<File>,
+        handle: u32,
+    ) -> Result<ARef<gem::Object<Self>>> {
+        gem::Object::lookup_handle(file, handle)
+    }
+}
diff --git a/drivers/gpu/drm/nova/nova.rs b/drivers/gpu/drm/nova/nova.rs
new file mode 100644
index 000000000000..902876aa14d1
--- /dev/null
+++ b/drivers/gpu/drm/nova/nova.rs
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Nova DRM Driver
+
+mod driver;
+mod file;
+mod gem;
+mod uapi;
+
+use crate::driver::NovaDriver;
+
+kernel::module_auxiliary_driver! {
+    type: NovaDriver,
+    name: "Nova",
+    author: "Danilo Krummrich",
+    description: "Nova GPU driver",
+    license: "GPL v2",
+}
diff --git a/drivers/gpu/drm/nova/uapi.rs b/drivers/gpu/drm/nova/uapi.rs
new file mode 100644
index 000000000000..eb228a58d423
--- /dev/null
+++ b/drivers/gpu/drm/nova/uapi.rs
@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use kernel::uapi;
+
+// TODO Work out some common infrastructure to avoid boilerplate code for uAPI abstractions.
+
+macro_rules! define_uapi_abstraction {
+    ($name:ident <= $inner:ty) => {
+        #[repr(transparent)]
+        pub struct $name(::kernel::types::Opaque<$inner>);
+
+        impl ::core::convert::From<&::kernel::types::Opaque<$inner>> for &$name {
+            fn from(value: &::kernel::types::Opaque<$inner>) -> Self {
+                // SAFETY: `Self` is a transparent wrapper of `$inner`.
+                unsafe { ::core::mem::transmute(value) }
+            }
+        }
+    };
+}
+
+define_uapi_abstraction!(Getparam <= uapi::drm_nova_getparam);
+
+impl Getparam {
+    pub fn param(&self) -> u64 {
+        // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_getparam`.
+        unsafe { (*self.0.get()).param }
+    }
+
+    pub fn set_value(&self, v: u64) {
+        // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_getparam`.
+        unsafe { (*self.0.get()).value = v };
+    }
+}
+
+define_uapi_abstraction!(GemCreate <= uapi::drm_nova_gem_create);
+
+impl GemCreate {
+    pub fn size(&self) -> u64 {
+        // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_gem_create`.
+        unsafe { (*self.0.get()).size }
+    }
+
+    pub fn set_handle(&self, handle: u32) {
+        // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_gem_create`.
+        unsafe { (*self.0.get()).handle = handle };
+    }
+}
+
+define_uapi_abstraction!(GemInfo <= uapi::drm_nova_gem_info);
+
+impl GemInfo {
+    pub fn handle(&self) -> u32 {
+        // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_gem_info`.
+        unsafe { (*self.0.get()).handle }
+    }
+
+    pub fn set_size(&self, size: u64) {
+        // SAFETY: `self.get()` is a valid pointer to a `struct drm_nova_gem_info`.
+        unsafe { (*self.0.get()).size = size };
+    }
+}