gpu: nova-core: gsp: Create rmargs

Initialise the GSP resource manager arguments (rmargs) which provides
initialisation parameters to the GSP firmware during boot. The rmargs
structure contains arguments to configure the GSP message/command queue
location.

These are mapped for coherent DMA and added to the libos data structure
for access when booting GSP.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Co-developed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-10-8ae4058e3c0e@nvidia.com>

1 files changed, 26 insertions, 1 deletions

diff --git a/drivers/gpu/nova-core/gsp/cmdq.rs b/drivers/gpu/nova-core/gsp/cmdq.rs
index c00d9fa9b79b..295903c28922 100644
--- a/drivers/gpu/nova-core/gsp/cmdq.rs
+++ b/drivers/gpu/nova-core/gsp/cmdq.rs
@@ -11,7 +11,10 @@ use core::{
 
 use kernel::{
     device,
-    dma::CoherentAllocation,
+    dma::{
+        CoherentAllocation,
+        DmaAddress, //
+    },
     dma_write,
     io::poll::read_poll_timeout,
     prelude::*,
@@ -33,6 +36,7 @@ use crate::{
             MsgqTxHeader, //
         },
         PteArray,
+        GSP_PAGE_SHIFT,
         GSP_PAGE_SIZE, //
     },
     num,
@@ -429,6 +433,22 @@ pub(crate) struct Cmdq {
 }
 
 impl Cmdq {
+    /// Offset of the data after the PTEs.
+    const POST_PTE_OFFSET: usize = core::mem::offset_of!(GspMem, cpuq);
+
+    /// Offset of command queue ring buffer.
+    pub(crate) const CMDQ_OFFSET: usize = core::mem::offset_of!(GspMem, cpuq)
+        + core::mem::offset_of!(Msgq, msgq)
+        - Self::POST_PTE_OFFSET;
+
+    /// Offset of message queue ring buffer.
+    pub(crate) const STATQ_OFFSET: usize = core::mem::offset_of!(GspMem, gspq)
+        + core::mem::offset_of!(Msgq, msgq)
+        - Self::POST_PTE_OFFSET;
+
+    /// Number of page table entries for the GSP shared region.
+    pub(crate) const NUM_PTES: usize = size_of::<GspMem>() >> GSP_PAGE_SHIFT;
+
     /// Creates a new command queue for `dev`.
     pub(crate) fn new(dev: &device::Device<device::Bound>) -> Result<Cmdq> {
         let gsp_mem = DmaGspMem::new(dev)?;
@@ -653,4 +673,9 @@ impl Cmdq {
 
         result
     }
+
+    /// Returns the DMA handle of the command queue's shared memory region.
+    pub(crate) fn dma_handle(&self) -> DmaAddress {
+        self.gsp_mem.0.dma_handle()
+    }
 }