security: Add memory subfolder

Add files to introduce a memory clearing framework.
Introduce Kconfig PLATFORM_HAS_DRAM_CLEAR that is to be selected by
platforms, that are able to clear all DRAM.

Introduce Kconfig SECURITY_CLEAR_DRAM_ON_REGULAR_BOOT that is user
selectable to always clear DRAM on non S3 boot.

The function security_clear_dram_request tells the calling platform when
to wipe all DRAM. Will be extended by TEE frameworks.

Add Documentation for the new security API.

Change-Id: Ifba25bfdd1057049f5cbae8968501bd9be487110
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/31548
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
Reviewed-by: Christian Walter <christian.walter@9elements.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/src/security/memory/memory.h b/src/security/memory/memory.h
new file mode 100644
index 0000000000..ccb07d76ad
--- /dev/null
+++ b/src/security/memory/memory.h
@@ -0,0 +1,19 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2019 9elements Agency GmbH
+ * Copyright (C) 2019 Facebook Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <stdint.h>
+
+bool security_clear_dram_request(void);