gpu: nova-core: firmware: gsp: use dma::Coherent for level0 table

Replace the nova-core local `DmaObject` with a `CoherentBox` that can
fulfill the same role.

Since `CoherentBox` is more flexible than `DmaObject`, we can use the
native `u64` type for page table entries instead of messing with bytes.

The `dma` module becomes unused with that change, so remove it as well.

Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/20260327-b4-nova-dma-removal-v2-7-616e1d0b5cb3@nvidia.com
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>

1 files changed, 0 insertions, 53 deletions

diff --git a/drivers/gpu/nova-core/dma.rs b/drivers/gpu/nova-core/dma.rs
deleted file mode 100644
index 3c19d5ffcfe8..000000000000
--- a/drivers/gpu/nova-core/dma.rs
+++ /dev/null
@@ -1,53 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-//! Simple DMA object wrapper.
-
-use core::ops::{
-    Deref,
-    DerefMut, //
-};
-
-use kernel::{
-    device,
-    dma::Coherent,
-    page::PAGE_SIZE,
-    prelude::*, //
-};
-
-pub(crate) struct DmaObject {
-    dma: Coherent<[u8]>,
-}
-
-impl DmaObject {
-    pub(crate) fn new(dev: &device::Device<device::Bound>, len: usize) -> Result<Self> {
-        let len = core::alloc::Layout::from_size_align(len, PAGE_SIZE)
-            .map_err(|_| EINVAL)?
-            .pad_to_align()
-            .size();
-        let dma = Coherent::zeroed_slice(dev, len, GFP_KERNEL)?;
-
-        Ok(Self { dma })
-    }
-
-    pub(crate) fn from_data(dev: &device::Device<device::Bound>, data: &[u8]) -> Result<Self> {
-        let dma_obj = Self::new(dev, data.len())?;
-        // SAFETY: We have just allocated the DMA memory, we are the only users and
-        // we haven't made the device aware of the handle yet.
-        unsafe { dma_obj.as_mut()[..data.len()].copy_from_slice(data) };
-        Ok(dma_obj)
-    }
-}
-
-impl Deref for DmaObject {
-    type Target = Coherent<[u8]>;
-
-    fn deref(&self) -> &Self::Target {
-        &self.dma
-    }
-}
-
-impl DerefMut for DmaObject {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        &mut self.dma
-    }
-}