feat(plat/st): manage io_policies with FCONF

Introduced IO policies management through the trusted
boot firmware config device tree for UUID references.

Change-Id: Ibeeabede51b0514ebba26dbbdae587363b2aa0a7
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
diff --git a/plat/st/common/include/stm32mp_fconf_getter.h b/plat/st/common/include/stm32mp_fconf_getter.h
new file mode 100644
index 0000000..3a8bb11
--- /dev/null
+++ b/plat/st/common/include/stm32mp_fconf_getter.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2021, STMicroelectronics - All Rights Reserved
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef STM32MP_FCONF_GETTER
+#define STM32MP_FCONF_GETTER
+
+#include <assert.h>
+
+#include <lib/fconf/fconf.h>
+
+/* IO policies */
+#define stm32mp__io_policies_getter(id) __extension__ ({	\
+	assert((id) < MAX_NUMBER_IDS);				\
+	&policies[id];						\
+})
+
+struct plat_io_policy {
+	uintptr_t *dev_handle;
+	uintptr_t image_spec;
+	int (*check)(const uintptr_t spec);
+};
+
+extern struct plat_io_policy policies[];
+int fconf_populate_stm32mp_io_policies(uintptr_t config);
+
+#endif /* STM32MP_FCONF_GETTER */