gpu: nova-core: falcon: Add support to write firmware version

This will be needed by both the GSP boot code as well as GSP resume code
in the sequencer.

Reviewed-by: Lyude Paul <[e-mail]>
Signed-off-by: Joel Fernandes <[e-mail]>
Signed-off-by: Alexandre Courbot <[e-mail]>
Message-ID: <[e-mail]>

drivers/gpu/nova-core/falcon.rs

···
         let cpuctl = regs::NV_PRISCV_RISCV_CPUCTL::read(bar, &E::ID);
         cpuctl.active_stat()
     }
+
+    /// Write the application version to the OS register.
+    #[expect(dead_code)]
+    pub(crate) fn write_os_version(&self, bar: &Bar0, app_version: u32) {
+        regs::NV_PFALCON_FALCON_OS::default()
+            .set_value(app_version)
+            .write(bar, &E::ID);
+    }
 }

drivers/gpu/nova-core/regs.rs

···
     31:0    value as u32;
 });
 
+// Used to store version information about the firmware running
+// on the Falcon processor.
+register!(NV_PFALCON_FALCON_OS @ PFalconBase[0x00000080] {
+    31:0    value as u32;
+});
+
 register!(NV_PFALCON_FALCON_RM @ PFalconBase[0x00000084] {
     31:0    value as u32;
 });