[PATCH v6 07/11] gpu: nova-core: gsp: Create rmargs

[Alistair Popple <apopple@nvidia.com>]

Initialise the GSP resource manager arguments (rmargs) which provide
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>

---

Changes for v5:
 - Derive Zeroable trait

Changes for v2:
 - Rebased on Alex's latest series
---
 drivers/gpu/nova-core/gsp.rs      | 17 ++++++++++
 drivers/gpu/nova-core/gsp/cmdq.rs | 24 ++++++++++++--
 drivers/gpu/nova-core/gsp/fw.rs   | 54 +++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/nova-core/gsp.rs b/drivers/gpu/nova-core/gsp.rs
index 31eeaf76526a..f08bb0924edb 100644
--- a/drivers/gpu/nova-core/gsp.rs
+++ b/drivers/gpu/nova-core/gsp.rs
@@ -17,6 +17,7 @@
 
 mod fw;
 
+use fw::GspArgumentsCached;
 use fw::LibosMemoryRegionInitArgument;
 
 pub(crate) mod cmdq;
@@ -35,6 +36,7 @@ pub(crate) struct Gsp {
     logintr: LogBuffer,
     logrm: LogBuffer,
     pub(crate) cmdq: Cmdq,
+    rmargs: CoherentAllocation<GspArgumentsCached>,
 }
 
 #[repr(C)]
@@ -118,11 +120,26 @@ pub(crate) fn new(pdev: &pci::Device<device::Bound>) -> Result<impl PinInit<Self
 
         let cmdq = Cmdq::new(dev)?;
 
+        let rmargs = CoherentAllocation::<GspArgumentsCached>::alloc_coherent(
+            dev,
+            1,
+            GFP_KERNEL | __GFP_ZERO,
+        )?;
+        dma_write!(libos[3] = LibosMemoryRegionInitArgument::new("RMARGS", &rmargs)?)?;
+
+        dma_write!(
+            rmargs[0] = fw::GspArgumentsCached::new(
+                fw::MessageQueueInitArguments::new(&cmdq),
+                fw::GspSrInitArguments::new()
+            )
+        )?;
+
         Ok(try_pin_init!(Self {
             libos,
             loginit,
             logintr,
             logrm,
+            rmargs,
             cmdq,
         }))
     }
diff --git a/drivers/gpu/nova-core/gsp/cmdq.rs b/drivers/gpu/nova-core/gsp/cmdq.rs
index 42973c52cb03..5589bb333c16 100644
--- a/drivers/gpu/nova-core/gsp/cmdq.rs
+++ b/drivers/gpu/nova-core/gsp/cmdq.rs
@@ -5,7 +5,7 @@
 use core::sync::atomic::Ordering;
 
 use kernel::device;
-use kernel::dma::CoherentAllocation;
+use kernel::dma::{CoherentAllocation, DmaAddress};
 use kernel::dma_write;
 use kernel::io::poll::read_poll_timeout;
 use kernel::prelude::*;
@@ -283,10 +283,25 @@ pub(crate) struct Cmdq {
     dev: ARef<device::Device>,
     seq: u32,
     gsp_mem: DmaGspMem,
-    pub _nr_ptes: u32,
 }
 
 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;
+
     pub(crate) fn new(dev: &device::Device<device::Bound>) -> Result<Cmdq> {
         let gsp_mem = DmaGspMem::new(dev)?;
         let nr_ptes = size_of::<GspMem>() >> GSP_PAGE_SHIFT;
@@ -296,7 +311,6 @@ pub(crate) fn new(dev: &device::Device<device::Bound>) -> Result<Cmdq> {
             dev: dev.into(),
             seq: 0,
             gsp_mem,
-            _nr_ptes: nr_ptes as u32,
         })
     }
 
@@ -514,4 +528,8 @@ pub(crate) fn receive_msg_from_gsp<M: MessageFromGsp, R>(
             .advance_cpu_read_ptr(msg_header.length().div_ceil(GSP_PAGE_SIZE as u32));
         result
     }
+
+    pub(crate) fn dma_handle(&self) -> DmaAddress {
+        self.gsp_mem.0.dma_handle()
+    }
 }
diff --git a/drivers/gpu/nova-core/gsp/fw.rs b/drivers/gpu/nova-core/gsp/fw.rs
index c74088bdf7c0..f862422714db 100644
--- a/drivers/gpu/nova-core/gsp/fw.rs
+++ b/drivers/gpu/nova-core/gsp/fw.rs
@@ -16,6 +16,7 @@
 
 use crate::firmware::gsp::GspFirmware;
 use crate::gpu::Chipset;
+use crate::gsp::cmdq::Cmdq;
 use crate::gsp::FbLayout;
 use crate::gsp::GSP_PAGE_SIZE;
 
@@ -483,3 +484,56 @@ unsafe impl AsBytes for GspMsgElement {}
 // SAFETY: This struct only contains integer types for which all bit patterns
 // are valid.
 unsafe impl FromBytes for GspMsgElement {}
+
+#[repr(transparent)]
+pub(crate) struct GspArgumentsCached(bindings::GSP_ARGUMENTS_CACHED);
+
+impl GspArgumentsCached {
+    pub(crate) fn new(
+        queue_arguments: MessageQueueInitArguments,
+        sr_arguments: GspSrInitArguments,
+    ) -> Self {
+        Self(bindings::GSP_ARGUMENTS_CACHED {
+            messageQueueInitArguments: queue_arguments.0,
+            srInitArguments: sr_arguments.0,
+            bDmemStack: 1,
+            ..Default::default()
+        })
+    }
+}
+
+// SAFETY: Padding is explicit and will not contain uninitialized data.
+unsafe impl AsBytes for GspArgumentsCached {}
+
+// SAFETY: This struct only contains integer types for which all bit patterns
+// are valid.
+unsafe impl FromBytes for GspArgumentsCached {}
+
+#[repr(transparent)]
+pub(crate) struct MessageQueueInitArguments(bindings::MESSAGE_QUEUE_INIT_ARGUMENTS);
+
+impl MessageQueueInitArguments {
+    pub(crate) fn new(cmdq: &Cmdq) -> Self {
+        Self(bindings::MESSAGE_QUEUE_INIT_ARGUMENTS {
+            sharedMemPhysAddr: cmdq.dma_handle(),
+            pageTableEntryCount: Cmdq::NUM_PTES as u32,
+            cmdQueueOffset: Cmdq::CMDQ_OFFSET as u64,
+            statQueueOffset: Cmdq::STATQ_OFFSET as u64,
+            ..Default::default()
+        })
+    }
+}
+
+#[repr(transparent)]
+pub(crate) struct GspSrInitArguments(bindings::GSP_SR_INIT_ARGUMENTS);
+
+impl GspSrInitArguments {
+    pub(crate) fn new() -> Self {
+        Self(bindings::GSP_SR_INIT_ARGUMENTS {
+            oldLevel: 0,
+            flags: 0,
+            bInPMTransition: 0,
+            ..Default::default()
+        })
+    }
+}
-- 
2.50.1