[fixup] core: init dt when no DTB observed from TL

Enhance the backwards compatibility to try to map the pass-in
DTB PA when no DTB exists in TL.
Fix coding style issues.

Signed-off-by: Raymond Mao <raymond.mao@linaro.org>

core/include/kernel/transfer_list.h

@@ -18,13 +18,13 @@
 
 // version of the register convention used.
 // Set to 1 for both AArch64 and AArch32 according to fw handoff spec v0.9
-#define REGISTER_CONVENTION_VERSION_MASK (1 << 24)
+#define REGISTER_CONVENTION_VERSION_MASK BIT(24)
 
 // transfer list operation codes
-#define TL_OPS_NON 	U(0)	// invalid for any operation
-#define TL_OPS_ALL 	U(1)	// valid for all operations
-#define TL_OPS_RO 	U(2)	// valid for read only
-#define TL_OPS_CUS 	U(3)	// either abort or switch to special code to interpret
+#define TL_OPS_NON	U(0)	// invalid for any operation
+#define TL_OPS_ALL	U(1)	// valid for all operations
+#define TL_OPS_RO	U(2)	// valid for read only
+#define TL_OPS_CUS	U(3)	// either abort or special code to interpret
 
 #ifndef __ASSEMBLER__
 
@@ -84,8 +84,9 @@ void transfer_list_unmap_nosync(struct transfer_list_header *tl);
 void transfer_list_dump(struct transfer_list_header *tl);
 struct transfer_list_header *transfer_list_init(void *pa, size_t max_size);
 
-struct transfer_list_header *transfer_list_relocate(struct transfer_list_header *tl,
-						    void *pa, size_t max_size);
+struct transfer_list_header *transfer_list_relocate
+					(struct transfer_list_header *tl,
+					 void *pa, size_t max_size);
 int transfer_list_check_header(const struct transfer_list_header *tl);
 
 void transfer_list_update_checksum(struct transfer_list_header *tl);
@@ -96,18 +97,24 @@ bool transfer_list_set_data_size(struct transfer_list_header *tl,
 				 uint32_t new_data_size);
 
 void *transfer_list_entry_data(struct transfer_list_entry *entry);
-bool transfer_list_rem(struct transfer_list_header *tl, struct transfer_list_entry *entry);
+bool transfer_list_rem(struct transfer_list_header *tl,
+		       struct transfer_list_entry *entry);
 
 struct transfer_list_entry *transfer_list_add(struct transfer_list_header *tl,
-					      uint16_t tag_id, uint32_t data_size,
+					      uint16_t tag_id,
+					      uint32_t data_size,
 					      const void *data);
 
-struct transfer_list_entry *transfer_list_add_with_align(struct transfer_list_header *tl,
-							 uint16_t tag_id, uint32_t data_size,
-							 const void *data, uint8_t alignment);
+struct transfer_list_entry *transfer_list_add_with_align
+					(struct transfer_list_header *tl,
+					 uint16_t tag_id,
+					 uint32_t data_size,
+					 const void *data,
+					 uint8_t alignment);
 
-struct transfer_list_entry *transfer_list_next(struct transfer_list_header *tl,
-					       struct transfer_list_entry *last);
+struct transfer_list_entry *transfer_list_next
+					(struct transfer_list_header *tl,
+					 struct transfer_list_entry *last);
 
 struct transfer_list_entry *transfer_list_find(struct transfer_list_header *tl,
 					       uint16_t tag_id);

core/kernel/dt.c

@@ -554,14 +554,12 @@ void init_external_dt(unsigned long phys_dt)
 	if (!IS_ENABLED(CFG_EXTERNAL_DT))
 		return;
 
-	if (IS_ENABLED(CFG_TRANSFER_LIST)) {
+	if (IS_ENABLED(CFG_TRANSFER_LIST))
 		// get DTB from the mapped TL
 		fdt = transfer_list_entry_data
 			(transfer_list_find(dt->tl, TL_TAG_FDT));
-		if (!fdt)
-			panic("No mapped DTB found from TL");
-	} else {
-		// map the DTB
+
+	if (!fdt) {
 		if (!phys_dt) {
 			/*
 			 * No need to panic as we're not using the DT in OP-TEE
@@ -576,6 +574,10 @@ void init_external_dt(unsigned long phys_dt)
 			return;
 		}
 
+		/*
+		 * if DTB does not exist in the mapped TL,
+		 * try to map the PA for backwards compatibility
+		 */
 		fdt = core_mmu_add_mapping(MEM_AREA_EXT_DT, phys_dt,
 					   CFG_DTB_MAX_SIZE);
 		if (!fdt)
@@ -635,6 +637,7 @@ static TEE_Result release_external_dt(void)
 				transfer_list_entry_data(te));
 			transfer_list_set_data_size
 				(tl, te, fdt_totalsize(external_dt.blob));
+
 			transfer_list_unmap_sync(tl); // unmap the TL
 		}
 	} else if (core_mmu_remove_mapping(MEM_AREA_EXT_DT, external_dt.blob,