[config] Make PXE stack a compile-time option

For extremely tight space requirements and specific applications, it is
sometimes desirable to create gPXE images that cannot provide the PXE API
functionality to client programs. Add a configuration header option,
PXE_STACK, that can be removed to remove this stack. Also add PXE_MENU
to control the PXE boot menu, which most uses of gPXE do not need.

Signed-off-by: Marty Connor <mdc@etherboot.org>

1 files changed, 19 insertions, 0 deletions

diff --git a/src/arch/i386/include/pxe_call.h b/src/arch/i386/include/pxe_call.h
index 50667e62d..4d2456169 100644
--- a/src/arch/i386/include/pxe_call.h
+++ b/src/arch/i386/include/pxe_call.h
@@ -34,5 +34,24 @@ extern void pxe_activate ( struct net_device *netdev );
 extern int pxe_deactivate ( void );
 extern int pxe_start_nbp ( void );
 extern __asmcall void pxe_api_call ( struct i386_all_regs *ix86 );
+extern int _pxe_api_call_weak ( struct i386_all_regs *ix86 )
+	__attribute__ (( weak ));
+
+/**
+ * Dispatch PXE API call weakly
+ *
+ * @v ix86		Registers for PXE call
+ * @ret present		Zero if the PXE stack is present, nonzero if not
+ *
+ * A successful return only indicates that the PXE stack was available
+ * for dispatching the call; it says nothing about the success of
+ * whatever the call asked for.
+ */
+static inline int pxe_api_call_weak ( struct i386_all_regs *ix86 )
+{
+	if ( _pxe_api_call_weak != NULL )
+		return _pxe_api_call_weak ( ix86 );
+	return -1;
+}
 
 #endif /* _PXE_CALL_H */