[PATCH 3/9] gpu: nova-core: return FSP response buffer to caller

[Zhi Wang]

Change send_sync_fsp() to return the raw response buffer after
validating the common MCTP/NVDM headers and error code. This allows
callers to perform protocol-specific parsing on the response payload,
which is needed for the upcoming PRC protocol support.

For the existing COT caller, the response buffer is unused.

Signed-off-by: Zhi Wang <zhiw@xxxxxxxxxx>
---
 drivers/gpu/nova-core/fsp.rs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/nova-core/fsp.rs b/drivers/gpu/nova-core/fsp.rs
index 78b90bfbfba4..5fd2e9e277b1 100644
--- a/drivers/gpu/nova-core/fsp.rs
+++ b/drivers/gpu/nova-core/fsp.rs
@@ -257,7 +257,8 @@ pub(crate) fn wait_secure_boot(
     }
 
     /// Sends a message to FSP and waits for the response.
-    fn send_sync_fsp<M>(&mut self, dev: &device::Device, bar: Bar0<'_>, msg: &M) -> Result
+    /// Returns the full response buffer on success.
+    fn send_sync_fsp<M>(&mut self, dev: &device::Device, bar: Bar0<'_>, msg: &M) -> Result<KVec<u8>>
     where
         M: MessageToFsp,
     {
@@ -315,7 +316,7 @@ fn send_sync_fsp<M>(&mut self, dev: &device::Device, bar: Bar0<'_>, msg: &M) ->
             return Err(EIO);
         }
 
-        Ok(())
+        Ok(response_buf)
     }
 
     /// Boots GSP FMC via FSP Chain of Trust.
@@ -336,7 +337,7 @@ pub(crate) fn boot_fmc(
             GFP_KERNEL,
         )?;
 
-        self.send_sync_fsp(dev, bar, &*msg)?;
+        let _response_buf = self.send_sync_fsp(dev, bar, &*msg)?;
 
         dev_dbg!(dev, "FSP Chain of Trust completed successfully\n");
         Ok(())
-- 
2.51.0