Support shared Mbed TLS heap for SGM

Change-Id: Ibbfedb6601feff51dfb82c1d94850716c5a36d24
Signed-off-by: John Tsichritzis <john.tsichritzis@arm.com>

plat/arm/css/sgm/fdts/sgm_tb_fw_config.dts

@@ -12,5 +12,16 @@
 		compatible = "arm,tb_fw";
 		hw_config_addr = <0x0 0x83000000>;
 		hw_config_max_size = <0x01000000>;
+		/*
+		 * The following two entries are placeholders for Mbed TLS
+		 * heap information. The default values don't matter since
+		 * they will be overwritten by BL1.
+		 * In case of having shared Mbed TLS heap between BL1 and BL2,
+		 * BL1 will populate these two properties with the respective
+		 * info about the shared heap. This info will be available for
+		 * BL2 in order to locate and re-use the heap.
+		 */
+		mbedtls_heap_addr = <0x0 0x0>;
+		mbedtls_heap_size = <0x0>;
 	};
 };

plat/arm/css/sgm/sgm_mmap_config.c

@@ -42,6 +42,9 @@ const mmap_region_t plat_arm_mmap[] = {
 	ARM_MAP_TSP_SEC_MEM,
 #ifdef SPD_opteed
 	ARM_OPTEE_PAGEABLE_LOAD_MEM,
+#endif
+#if TRUSTED_BOARD_BOOT && LOAD_IMAGE_V2 && !BL2_AT_EL3
+	ARM_MAP_BL1_RW,
 #endif
 	{0}
 };

plat/arm/css/sgm/sgm_plat_config.c

@@ -67,3 +67,13 @@ css_plat_config_t *get_plat_config(void)
 	assert(css_plat_info != NULL);
 	return css_plat_info;
 }
+
+#if TRUSTED_BOARD_BOOT && LOAD_IMAGE_V2
+int plat_get_mbedtls_heap(void **heap_addr, size_t *heap_size)
+{
+	assert(heap_addr != NULL);
+	assert(heap_size != NULL);
+
+	return arm_get_mbedtls_heap(heap_addr, heap_size);
+}
+#endif