[efi] Provide a multiprocessor API for EFI

Provide an implementation of the iPXE multiprocessor API for EFI,
based on using EFI_MP_SERVICES to start up a wrapper function on all
application processors.

Note that the processor numbers used by EFI_MP_SERVICES are opaque
integers that bear no relation to the underlying CPU identity
(e.g. the APIC ID), and so we must rely on our own (architecture-
specific) implementation to determine the relevant CPU identifiers.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 30 insertions, 0 deletions

diff --git a/src/include/ipxe/efi/efi_mp.h b/src/include/ipxe/efi/efi_mp.h
new file mode 100644
index 00000000..8dc4243e
--- /dev/null
+++ b/src/include/ipxe/efi/efi_mp.h
@@ -0,0 +1,30 @@
+#ifndef _IPXE_EFI_MP_H
+#define _IPXE_EFI_MP_H
+
+/** @file
+ *
+ * EFI multiprocessor API implementation
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+#ifdef MPAPI_EFI
+#define MPAPI_PREFIX_efi
+#else
+#define MPAPI_PREFIX_efi __efi_
+#endif
+
+/**
+ * Calculate address as seen by a multiprocessor function
+ *
+ * @v address		Address in boot processor address space
+ * @ret address		Address in application processor address space
+ */
+static inline __attribute__ (( always_inline )) mp_addr_t
+MPAPI_INLINE ( efi, mp_address ) ( void *address ) {
+
+	return ( ( mp_addr_t ) address );
+}
+
+#endif /* _IPXE_EFI_MP_H */