From cdfe43454f6ce18654b233e0d2478ce091e60f65 Mon Sep 17 00:00:00 2001
From: Etienne Carriere <etienne.carriere@foss.st.com>
Date: Thu, 12 Dec 2024 17:07:56 +0100
Subject: [PATCH] optee ftpm: CFG_TA_FTPM_RPMB_STORAGE selects RPMB storage

Adds configuration switch CFG_TA_FTPM_RPMB_STORAGE that, when enable,
makes fTPM OP-TEE TA to explicitly use the eMMC RPMB secure storage of
OP-TEE instead of OP-TEE private storage which depends on OP-TEE
configuration. The configuration switch is default disabled for
compatibility reasons.

Signed-off-by: Etienne Carriere <etienne.carriere@foss.st.com>
---
 platform/NVMem.c | 12 +++++++++---
 sub.mk           |  3 +++
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/platform/NVMem.c b/platform/NVMem.c
index fad411b..4421339 100644
--- a/platform/NVMem.c
+++ b/platform/NVMem.c
@@ -49,6 +49,12 @@
 #include <tee_internal_api.h>
 #include <tee_internal_api_extensions.h>
 
+#ifdef CFG_TA_FTPM_RPMB_STORAGE
+#define CHOOSEN_TEE_STORAGE	TEE_STORAGE_PRIVATE_RPMB
+#else
+#define CHOOSEN_TEE_STORAGE	TEE_STORAGE_PRIVATE
+#endif
+
 //
 // Overall size of NV, not just the TPM's NV storage
 //
@@ -157,7 +163,7 @@ _plat__NvInitFromStorage()
 		objID = s_StorageObjectID + i;
 
 		// Attempt to open TEE persistent storage object.
-		Result = TEE_OpenPersistentObject(TEE_STORAGE_PRIVATE,
+		Result = TEE_OpenPersistentObject(CHOOSEN_TEE_STORAGE,
 									      (void *)&objID,
 									      sizeof(objID),
 									      TA_STORAGE_FLAGS,
@@ -175,7 +181,7 @@ _plat__NvInitFromStorage()
 			}
 
 			// Storage object was not found, create it.
-			Result = TEE_CreatePersistentObject(TEE_STORAGE_PRIVATE,
+			Result = TEE_CreatePersistentObject(CHOOSEN_TEE_STORAGE,
 										        (void *)&objID,
 										        sizeof(objID),
 										        TA_STORAGE_FLAGS,
@@ -313,7 +319,7 @@ _plat__NvWriteBack()
 			// Force storage stack to update its backing store
             TEE_CloseObject(s_NVStore[i]);
 
-            Result = TEE_OpenPersistentObject(TEE_STORAGE_PRIVATE,
+            Result = TEE_OpenPersistentObject(CHOOSEN_TEE_STORAGE,
                                               (void *)&objID,
                                               sizeof(objID),
                                               TA_STORAGE_FLAGS,
diff --git a/sub.mk b/sub.mk
index e317865..047b5bd 100644
--- a/sub.mk
+++ b/sub.mk
@@ -1,4 +1,5 @@
 CFG_FTPM_EMULATE_PPI ?= n
+CFG_TA_FTPM_RPMB_STORAGE ?= n
 
 #
 # The fTPM needs to overwrite some of the header files used in the
@@ -95,6 +96,8 @@ srcs-y += platform/fTPM_helpers.c
 
 srcs-y += fTPM.c
 
+cflags-$(CFG_TA_FTPM_RPMB_STORAGE) += -DCFG_TA_FTPM_RPMB_STORAGE
+
 ifeq ($(CFG_TA_MEASURED_BOOT),y)
 CFG_TA_EVENT_LOG_SIZE ?= 1024
 # Support for Trusted Firmware Measured Boot.