[PATCH v2 03/10] gpu: nova-core: gsp: ensure lifetime for FMC boot DMA allocations

Currently, `FmcBootArgs` takes DMA handles directly, rather than
references to the `Coherent` for them. This is error prone, so instead
store lifetime'd references to the `Coherent` allocation.

Signed-off-by: Eliot Courtney <[email protected]>
---
 drivers/gpu/nova-core/fsp.rs           | 32 ++++++++++++++++++++------------
 drivers/gpu/nova-core/gsp.rs           |  6 ++----
 drivers/gpu/nova-core/gsp/hal/gh100.rs | 19 +++++++------------
 3 files changed, 29 insertions(+), 28 deletions(-)

diff --git a/drivers/gpu/nova-core/fsp.rs b/drivers/gpu/nova-core/fsp.rs
index f0c595175c9c..5b782aa2e3fd 100644
--- a/drivers/gpu/nova-core/fsp.rs
+++ b/drivers/gpu/nova-core/fsp.rs
@@ -40,7 +40,11 @@
         FIRMWARE_VERSION, //
     },
     gpu::Chipset,
-    gsp::GspFmcBootParams,
+    gsp::{
+        GspFmcBootParams,
+        GspFwWprMeta,
+        LibosMemoryRegionInitArgument, //
+    },
     mctp::{
         MctpHeader,
         NvdmHeader,
@@ -134,7 +138,7 @@ impl FspCotMessage {
     fn new<'a>(
         fb_layout: &FbLayout,
         fsp_fw: &'a FspFirmware,
-        args: &'a FmcBootArgs,
+        args: &'a FmcBootArgs<'_>,
     ) -> Result<impl Init<Self> + 'a> {
         // frts_vidmem_offset is measured from the end of FB, so FRTS sits at
         // (end of FB) - frts_vidmem_offset.
@@ -188,35 +192,39 @@ impl MessageToFsp for FspCotMessage {
 }
 
 /// Bundled arguments for FMC boot via FSP Chain of Trust.
-pub(crate) struct FmcBootArgs {
+pub(crate) struct FmcBootArgs<'a> {
     chipset: Chipset,
     fmc_boot_params: Coherent<GspFmcBootParams>,
     resume: bool,
+    // Additional dependencies required to be kept alive for FMC boot.
+    _wpr_meta: &'a Coherent<GspFwWprMeta>,
+    _libos: &'a Coherent<[LibosMemoryRegionInitArgument]>,
 }
 
-impl FmcBootArgs {
+impl<'a> FmcBootArgs<'a> {
     /// Builds FMC boot arguments, allocating the DMA-coherent boot parameter
     /// structure that FSP will read.
     pub(crate) fn new(
         dev: &device::Device<device::Bound>,
         chipset: Chipset,
-        wpr_meta_addr: u64,
-        libos_addr: u64,
+        wpr_meta: &'a Coherent<GspFwWprMeta>,
+        libos: &'a Coherent<[LibosMemoryRegionInitArgument]>,
         resume: bool,
     ) -> Result<Self> {
-        let init = GspFmcBootParams::new(wpr_meta_addr, libos_addr);
+        let init = GspFmcBootParams::new(wpr_meta.dma_handle(), libos.dma_handle());
 
         Ok(Self {
             chipset,
             fmc_boot_params: Coherent::<GspFmcBootParams>::init(dev, GFP_KERNEL, init)?,
             resume,
+            _wpr_meta: wpr_meta,
+            _libos: libos,
         })
     }
 
-    /// DMA address of the FMC boot parameters, needed after boot for lockdown
-    /// release polling.
-    pub(crate) fn boot_params_dma_handle(&self) -> u64 {
-        self.fmc_boot_params.dma_handle()
+    /// Returns the FMC boot parameters allocation.
+    pub(crate) fn boot_params(&self) -> &Coherent<GspFmcBootParams> {
+        &self.fmc_boot_params
     }
 }
 
@@ -332,7 +340,7 @@ pub(crate) fn boot_fmc(
         &mut self,
         dev: &device::Device<device::Bound>,
         fb_layout: &FbLayout,
-        args: &FmcBootArgs,
+        args: &FmcBootArgs<'_>,
     ) -> Result {
         dev_dbg!(dev, "Starting FSP boot sequence for {}\n", args.chipset);
 
diff --git a/drivers/gpu/nova-core/gsp.rs b/drivers/gpu/nova-core/gsp.rs
index e89366b425fb..f0242126e202 100644
--- a/drivers/gpu/nova-core/gsp.rs
+++ b/drivers/gpu/nova-core/gsp.rs
@@ -28,6 +28,7 @@
 pub(crate) use fw::{
     GspFmcBootParams,
     GspFwWprMeta,
+    LibosMemoryRegionInitArgument,
     LibosParams, //
 };
 
@@ -45,10 +46,7 @@
     },
     gsp::{
         cmdq::Cmdq,
-        fw::{
-            GspArgumentsPadded,
-            LibosMemoryRegionInitArgument, //
-        },
+        fw::GspArgumentsPadded, //
     },
     num,
 };
diff --git a/drivers/gpu/nova-core/gsp/hal/gh100.rs b/drivers/gpu/nova-core/gsp/hal/gh100.rs
index de786871c8ec..270703d0f5c6 100644
--- a/drivers/gpu/nova-core/gsp/hal/gh100.rs
+++ b/drivers/gpu/nova-core/gsp/hal/gh100.rs
@@ -24,6 +24,7 @@
         },
         Gsp,
         GspBootContext,
+        GspFmcBootParams,
         GspFwWprMeta, //
     },
 };
@@ -55,13 +56,13 @@ fn combined_addr(&self) -> u64 {
     fn lockdown_released_or_error(
         &self,
         gsp_falcon: &Falcon<'_, GspEngine>,
-        fmc_boot_params_addr: u64,
+        fmc_boot_params: &Coherent<GspFmcBootParams>,
     ) -> bool {
         // GSP-FMC normally clears the boot parameters address from the mailboxes early during
         // boot. If the address is still there, keep polling rather than treating it as an error.
         // Any other non-zero mailbox0 value is a GSP-FMC error code.
         if self.mbox0 != 0 {
-            return self.combined_addr() != fmc_boot_params_addr;
+            return self.combined_addr() != fmc_boot_params.dma_handle();
         }
 
         !gsp_falcon.riscv_branch_privilege_lockdown()
@@ -72,7 +73,7 @@ fn lockdown_released_or_error(
 fn wait_for_gsp_lockdown_release(
     dev: &device::Device<device::Bound>,
     gsp_falcon: &Falcon<'_, GspEngine>,
-    fmc_boot_params_addr: u64,
+    fmc_boot_params: &Coherent<GspFmcBootParams>,
 ) -> Result {
     dev_dbg!(dev, "Waiting for GSP lockdown release\n");
 
@@ -87,7 +88,7 @@ fn wait_for_gsp_lockdown_release(
         },
         |mbox| match mbox {
             None => false,
-            Some(mbox) => mbox.lockdown_released_or_error(gsp_falcon, fmc_boot_params_addr),
+            Some(mbox) => mbox.lockdown_released_or_error(gsp_falcon, fmc_boot_params),
         },
         Delta::from_millis(10),
         Delta::from_secs(30),
@@ -148,19 +149,13 @@ fn boot(
 
         let fsp = ctx.fsp.as_mut().ok_or(ENODEV)?;
 
-        let args = FmcBootArgs::new(
-            dev,
-            chipset,
-            wpr_meta.dma_handle(),
-            gsp.libos.dma_handle(),
-            false,
-        )?;
+        let args = FmcBootArgs::new(dev, chipset, wpr_meta, &gsp.libos, false)?;
 
         // Keep the result as we want to wait for lockdown release even in case of error, to make
         // sure `args` is not accessed by the GSP anymore.
         let res = fsp.boot_fmc(dev, fb_layout, &args);
 
-        wait_for_gsp_lockdown_release(dev, gsp_falcon, args.boot_params_dma_handle())?;
+        wait_for_gsp_lockdown_release(dev, gsp_falcon, args.boot_params())?;
 
         res.map(|()| Some(unload_bundle))
     }

-- 
2.54.0