[PATCH 2/4] gpu: nova: Add DRM registration data

[Alistair Popple <apopple@nvidia.com>]

Currently the nova-drm stub driver doesn't really interact with a real
device, so it doesn't have any registration data and has no way to call
into nova-core.

To allow for this add a DrmRegData type which will hold a reference to
the NovaCoreApi associated with the auxbus device.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Suggested-by: Danilo Krummrich <dakr@kernel.org>
---
 drivers/gpu/drm/nova/driver.rs | 16 ++++++++++++++--
 drivers/gpu/drm/nova/file.rs   | 13 ++++++-------
 2 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/nova/driver.rs b/drivers/gpu/drm/nova/driver.rs
index 739690bc2db5..3ae719540e4d 100644
--- a/drivers/gpu/drm/nova/driver.rs
+++ b/drivers/gpu/drm/nova/driver.rs
@@ -1,5 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 
+use core::pin::Pin;
+
 use kernel::{
     auxiliary,
     device::{
@@ -17,6 +19,7 @@
 
 use crate::file::File;
 use crate::gem::NovaObject;
+use nova_core::api::NovaCoreApi;
 
 pub(crate) struct NovaDriver;
 
@@ -26,6 +29,12 @@ pub(crate) struct Nova<'bound> {
     _reg: drm::Registration<'bound, NovaDriver>,
 }
 
+/// DRM registration data, accessible from ioctl handlers via the registration guard.
+pub(crate) struct DrmRegData<'bound> {
+    #[allow(dead_code)]
+    pub(crate) api: Pin<&'bound NovaCoreApi<'bound>>,
+}
+
 /// Convienence type alias for the DRM device type for this driver
 pub(crate) type NovaDevice<Ctx = drm::Normal> = drm::Device<NovaDriver, Ctx>;
 
@@ -60,9 +69,12 @@ fn probe<'bound>(
         _info: &'bound Self::IdInfo,
     ) -> impl PinInit<Self::Data<'bound>, Error> + 'bound {
         let drm = drm::UnregisteredDevice::<Self>::new(adev, Ok(()))?;
+        let reg_data = DrmRegData {
+            api: NovaCoreApi::of(adev)?,
+        };
         // SAFETY: `reg` is stored in `Nova` and dropped when the driver is unbound; it is
         // never forgotten.
-        let reg = unsafe { drm::Registration::new(adev.as_ref(), drm, (), 0)? };
+        let reg = unsafe { drm::Registration::new(adev.as_ref(), drm, reg_data, 0)? };
 
         Ok(Nova {
             drm: reg.device().into(),
@@ -74,7 +86,7 @@ fn probe<'bound>(
 #[vtable]
 impl drm::Driver for NovaDriver {
     type Data = ();
-    type RegistrationData<'a> = ();
+    type RegistrationData<'a> = DrmRegData<'a>;
     type File = File;
     type Object = gem::Object<NovaObject>;
     type ParentDevice<Ctx: DeviceContext> = auxiliary::Device<Ctx>;
diff --git a/drivers/gpu/drm/nova/file.rs b/drivers/gpu/drm/nova/file.rs
index 298c02bacb4b..855b6ffe696f 100644
--- a/drivers/gpu/drm/nova/file.rs
+++ b/drivers/gpu/drm/nova/file.rs
@@ -1,11 +1,10 @@
 // SPDX-License-Identifier: GPL-2.0
 
-use crate::driver::{NovaDevice, NovaDriver};
+use crate::driver::{DrmRegData, NovaDevice, NovaDriver};
 use crate::gem::NovaObject;
 use kernel::{
     alloc::flags::*,
     auxiliary,
-    device::Bound,
     drm::{
         self,
         gem::BaseObject,
@@ -30,12 +29,12 @@ impl File {
     /// IOCTL: get_param: Query GPU / driver metadata.
     pub(crate) fn get_param(
         dev: &NovaDevice<Registered>,
-        _reg_data: &(),
+        _reg_data: &DrmRegData<'_>,
         getparam: &mut uapi::drm_nova_getparam,
         _file: &drm::File<File>,
     ) -> Result<u32> {
-        let adev: &auxiliary::Device<Bound> = dev.as_ref();
-        let pdev: &pci::Device<Bound> = adev.parent().try_into()?;
+        let adev: &auxiliary::Device<_> = dev.as_ref();
+        let pdev: &pci::Device<_> = adev.parent().try_into()?;
 
         let value = match getparam.param as u32 {
             uapi::NOVA_GETPARAM_VRAM_BAR_SIZE => pdev.resource_len(1)?,
@@ -50,7 +49,7 @@ pub(crate) fn get_param(
     /// IOCTL: gem_create: Create a new DRM GEM object.
     pub(crate) fn gem_create(
         dev: &NovaDevice<Registered>,
-        _reg_data: &(),
+        _reg_data: &DrmRegData<'_>,
         req: &mut uapi::drm_nova_gem_create,
         file: &drm::File<File>,
     ) -> Result<u32> {
@@ -64,7 +63,7 @@ pub(crate) fn gem_create(
     /// IOCTL: gem_info: Query GEM metadata.
     pub(crate) fn gem_info(
         _dev: &NovaDevice<Registered>,
-        _reg_data: &(),
+        _reg_data: &DrmRegData<'_>,
         req: &mut uapi::drm_nova_gem_info,
         file: &drm::File<File>,
     ) -> Result<u32> {
-- 
2.54.0