[PATCH v8 1/7] drm/tyr: add resources to RegistrationData

[Deborah Brouwer]

Currently Tyr is not storing any resources in its drm::Driver
RegistrationData.

Move Tyr's device-private resources and gpu information from
drm::Driver::Data to drm::Driver::RegistrationData. This allows Tyr to
access this data safely within the lifetime of its binding to its parent
platform device and while registered with userspace.

Reviewed-by: Daniel Almeida <daniel.almeida@xxxxxxxxxxxxx>
Signed-off-by: Deborah Brouwer <deborah.brouwer@xxxxxxxxxxxxx>
---
 drivers/gpu/drm/tyr/driver.rs | 42 +++++++++++++++++++++---------------------
 drivers/gpu/drm/tyr/file.rs   | 11 ++++++-----
 2 files changed, 27 insertions(+), 26 deletions(-)

diff --git a/drivers/gpu/drm/tyr/driver.rs b/drivers/gpu/drm/tyr/driver.rs
index 8348c6cd3929..46ce5c41e310 100644
--- a/drivers/gpu/drm/tyr/driver.rs
+++ b/drivers/gpu/drm/tyr/driver.rs
@@ -6,6 +6,7 @@
         OptionalClk, //
     },
     device::{
+        Bound,
         Core,
         Device,
         DeviceContext, //
@@ -27,10 +28,7 @@
     regulator,
     regulator::Regulator,
     sizes::SZ_2M,
-    sync::{
-        aref::ARef,
-        Mutex, //
-    },
+    sync::Mutex,
     time, //
 };
 
@@ -53,13 +51,17 @@
 
 #[pin_data(PinnedDrop)]
 pub(crate) struct TyrPlatformDriverData<'bound> {
-    _device: ARef<TyrDrmDevice>,
     _reg: drm::Registration<'bound, TyrDrmDriver>,
 }
 
+/// Data owned by the DRM [`Registration`].
+///
+/// This data can have references tied to the parent platform device binding scope
+/// and is accessible only while the DRM device is registered with userspace.
 #[pin_data]
-pub(crate) struct TyrDrmDeviceData {
-    pub(crate) pdev: ARef<platform::Device>,
+pub(crate) struct TyrDrmRegistrationData<'bound> {
+    /// Parent platform device.
+    pub(crate) pdev: &'bound platform::Device<Bound>,
 
     #[pin]
     clks: Mutex<Clocks>,
@@ -67,9 +69,10 @@ pub(crate) struct TyrDrmDeviceData {
     #[pin]
     regulators: Mutex<Regulators>,
 
-    /// Some information on the GPU.
-    ///
-    /// This is mainly queried by userspace, i.e.: Mesa.
+    /// GPU MMIO register mapping.
+    pub(crate) iomem: IoMem<'bound>,
+
+    /// GPU information read from hardware during probe.
     pub(crate) gpu_info: GpuInfo,
 }
 
@@ -134,10 +137,10 @@ fn probe<'bound>(
         // other threads of execution.
         unsafe { pdev.dma_set_mask_and_coherent(DmaMask::try_new(pa_bits)?)? };
 
-        let platform: ARef<platform::Device> = pdev.into();
+        let unreg_dev = drm::UnregisteredDevice::<TyrDrmDriver>::new(pdev, Ok(()))?;
 
-        let data = try_pin_init!(TyrDrmDeviceData {
-                pdev: platform.clone(),
+        let reg_data = try_pin_init!(TyrDrmRegistrationData {
+                pdev,
                 clks <- new_mutex!(Clocks {
                     core: core_clk,
                     stacks: stacks_clk,
@@ -147,18 +150,15 @@ fn probe<'bound>(
                     _mali: mali_regulator,
                     _sram: sram_regulator,
                 }),
+                iomem,
                 gpu_info,
         });
 
-        let tdev = drm::UnregisteredDevice::<TyrDrmDriver>::new(pdev, data)?;
         // SAFETY: `reg` is stored in `TyrPlatformDriverData` and dropped when the driver is
         // unbound; it is never forgotten.
-        let reg = unsafe { drm::Registration::new(pdev.as_ref(), tdev, (), 0)? };
+        let reg = unsafe { drm::Registration::new(pdev.as_ref(), unreg_dev, reg_data, 0)? };
 
-        let driver = TyrPlatformDriverData {
-            _device: reg.device().into(),
-            _reg: reg,
-        };
+        let driver = TyrPlatformDriverData { _reg: reg };
 
         // We need this to be dev_info!() because dev_dbg!() does not work at
         // all in Rust for now, and we need to see whether probe succeeded.
@@ -184,8 +184,8 @@ fn drop(self: Pin<&mut Self>) {}
 
 #[vtable]
 impl drm::Driver for TyrDrmDriver {
-    type Data = TyrDrmDeviceData;
-    type RegistrationData<'a> = ();
+    type Data = ();
+    type RegistrationData<'bound> = TyrDrmRegistrationData<'bound>;
     type File = TyrDrmFileData;
     type Object = drm::gem::shmem::Object<BoData>;
     type ParentDevice<Ctx: DeviceContext> = platform::Device<Ctx>;
diff --git a/drivers/gpu/drm/tyr/file.rs b/drivers/gpu/drm/tyr/file.rs
index b686041d5d6b..9f60a90d4948 100644
--- a/drivers/gpu/drm/tyr/file.rs
+++ b/drivers/gpu/drm/tyr/file.rs
@@ -12,7 +12,8 @@
 
 use crate::driver::{
     TyrDrmDevice,
-    TyrDrmDriver, //
+    TyrDrmDriver,
+    TyrDrmRegistrationData, //
 };
 
 #[pin_data]
@@ -31,15 +32,15 @@ fn open(_dev: &drm::Device<Self::Driver>) -> Result<Pin<KBox<Self>>> {
 
 impl TyrDrmFileData {
     pub(crate) fn dev_query(
-        ddev: &TyrDrmDevice<Registered>,
-        _reg_data: &(),
+        _ddev: &TyrDrmDevice<Registered>,
+        reg_data: &TyrDrmRegistrationData<'_>,
         devquery: &mut uapi::drm_panthor_dev_query,
         _file: &TyrDrmFile,
     ) -> Result<u32> {
         if devquery.pointer == 0 {
             match devquery.type_ {
                 uapi::drm_panthor_dev_query_type_DRM_PANTHOR_DEV_QUERY_GPU_INFO => {
-                    devquery.size = core::mem::size_of_val(&ddev.gpu_info) as u32;
+                    devquery.size = core::mem::size_of_val(&reg_data.gpu_info) as u32;
                     Ok(0)
                 }
                 _ => Err(EINVAL),
@@ -53,7 +54,7 @@ pub(crate) fn dev_query(
                     )
                     .writer();
 
-                    writer.write(&ddev.gpu_info)?;
+                    writer.write(&reg_data.gpu_info)?;
 
                     Ok(0)
                 }

-- 
2.55.0