1 files changed, 60 insertions, 0 deletions
diff --git a/drivers/gpu/nova-core/gsp/fw.rs b/drivers/gpu/nova-core/gsp/fw.rs
index 436c00d07b16..458b5610061f 100644
--- a/drivers/gpu/nova-core/gsp/fw.rs
+++ b/drivers/gpu/nova-core/gsp/fw.rs
@@ -8,11 +8,16 @@ use r570_144 as bindings;
 use core::ops::Range;
 
 use kernel::{
+    dma::CoherentAllocation,
     ptr::{
         Alignable,
         Alignment, //
     },
     sizes::SZ_1M,
+    transmute::{
+        AsBytes,
+        FromBytes, //
+    },
 };
 
 use crate::{
@@ -116,3 +121,58 @@ impl LibosParams {
 /// addresses of the GSP bootloader and firmware.
 #[repr(transparent)]
 pub(crate) struct GspFwWprMeta(bindings::GspFwWprMeta);
+
+/// Struct containing the arguments required to pass a memory buffer to the GSP
+/// for use during initialisation.
+///
+/// The GSP only understands 4K pages (GSP_PAGE_SIZE), so even if the kernel is
+/// configured for a larger page size (e.g. 64K pages), we need to give
+/// the GSP an array of 4K pages. Since we only create physically contiguous
+/// buffers the math to calculate the addresses is simple.
+///
+/// The buffers must be a multiple of GSP_PAGE_SIZE.  GSP-RM also currently
+/// ignores the @kind field for LOGINIT, LOGINTR, and LOGRM, but expects the
+/// buffers to be physically contiguous anyway.
+///
+/// The memory allocated for the arguments must remain until the GSP sends the
+/// init_done RPC.
+#[repr(transparent)]
+pub(crate) struct LibosMemoryRegionInitArgument(bindings::LibosMemoryRegionInitArgument);
+
+// SAFETY: Padding is explicit and does not contain uninitialized data.
+unsafe impl AsBytes for LibosMemoryRegionInitArgument {}
+
+// SAFETY: This struct only contains integer types for which all bit patterns
+// are valid.
+unsafe impl FromBytes for LibosMemoryRegionInitArgument {}
+
+impl LibosMemoryRegionInitArgument {
+    pub(crate) fn new<A: AsBytes + FromBytes>(
+        name: &'static str,
+        obj: &CoherentAllocation<A>,
+    ) -> Self {
+        /// Generates the `ID8` identifier required for some GSP objects.
+        fn id8(name: &str) -> u64 {
+            let mut bytes = [0u8; core::mem::size_of::<u64>()];
+
+            for (c, b) in name.bytes().rev().zip(&mut bytes) {
+                *b = c;
+            }
+
+            u64::from_ne_bytes(bytes)
+        }
+
+        Self(bindings::LibosMemoryRegionInitArgument {
+            id8: id8(name),
+            pa: obj.dma_handle(),
+            size: num::usize_as_u64(obj.size()),
+            kind: num::u32_into_u8::<
+                { bindings::LibosMemoryRegionKind_LIBOS_MEMORY_REGION_CONTIGUOUS },
+            >(),
+            loc: num::u32_into_u8::<
+                { bindings::LibosMemoryRegionLoc_LIBOS_MEMORY_REGION_LOC_SYSMEM },
+            >(),
+            ..Default::default()
+        })
+    }
+}