diff --git a/drivers/gpu/nova-core/api.rs b/drivers/gpu/nova-core/api.rs
index f02c6c7c7e51..29207c4bb743 100644
--- a/drivers/gpu/nova-core/api.rs
+++ b/drivers/gpu/nova-core/api.rs
@@ -15,8 +15,11 @@
 
 pub use crate::gpu::Spec;
 
-use crate::gpu::Gpu;
-use crate::gsp::commands::GetGspStaticInfoReply;
+use crate::{
+    driver,
+    gpu::Gpu,
+    gsp::commands::GetGspStaticInfoReply, //
+};
 
 /// API handle for the auxiliary bus child drivers to interact with nova-core.
 pub struct NovaCoreApi<'bound> {
@@ -44,7 +47,9 @@ pub fn spec(&self) -> &Spec {
     /// Returns the size of the PCIe BAR used for accessing VRAM, typically
     /// BAR1.
     pub fn bar1_size(&self) -> Result<u64> {
-        self.pdev.resource_len(1)
+        let bar1 = driver::bar1_resource_index(self.pdev)?;
+
+        self.pdev.resource_len(bar1)
     }
 }