smbios: Expose in efi_loader as table

We can pass SMBIOS easily as EFI configuration table to an EFI payload. This
patch adds enablement for that case.

While at it, we also enable SMBIOS generation for ARM systems, since they support
EFI_LOADER.

Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

lib/efi_loader/efi_smbios.c

@@ -0,0 +1,32 @@
+/*
+ *  EFI application tables support
+ *
+ *  Copyright (c) 2016 Alexander Graf
+ *
+ *  SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <efi_loader.h>
+#include <inttypes.h>
+#include <smbios.h>
+
+static const efi_guid_t smbios_guid = SMBIOS_TABLE_GUID;
+
+void efi_smbios_register(void)
+{
+	/* Map within the low 32 bits, to allow for 32bit SMBIOS tables */
+	uint64_t dmi = 0xffffffff;
+	/* Reserve 4kb for SMBIOS */
+	uint64_t pages = 1;
+	int memtype = EFI_RUNTIME_SERVICES_DATA;
+
+	if (efi_allocate_pages(1, memtype, pages, &dmi) != EFI_SUCCESS)
+		return;
+
+	/* Generate SMBIOS tables */
+	write_smbios_table(dmi);
+
+	/* And expose them to our EFI payload */
+	efi_install_configuration_table(&smbios_guid, (void*)(uintptr_t)dmi);
+}