1 /*
2  * Copyright (c) 2023, Advanced Micro Devices, Inc. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  */
7 #include <common/debug.h>
8 #include <common/fdt_fixup.h>
9 #include <common/fdt_wrappers.h>
10 #include <libfdt.h>
11 #include <lib/xlat_tables/xlat_tables_v2.h>
12 
13 #include <plat_fdt.h>
14 #include <platform_def.h>
15 
prepare_dtb(void)16 void prepare_dtb(void)
17 {
18 #if defined(XILINX_OF_BOARD_DTB_ADDR)
19 	void *dtb;
20 	int map_ret = 0;
21 	int ret = 0;
22 
23 	dtb = (void *)XILINX_OF_BOARD_DTB_ADDR;
24 
25 	if (!IS_TFA_IN_OCM(BL31_BASE)) {
26 
27 #if defined(PLAT_XLAT_TABLES_DYNAMIC)
28 		map_ret = mmap_add_dynamic_region((unsigned long long)dtb,
29 						 (uintptr_t)dtb,
30 						 XILINX_OF_BOARD_DTB_MAX_SIZE,
31 						 MT_MEMORY | MT_RW | MT_NS);
32 		if (map_ret != 0) {
33 			WARN("Failed to add dynamic region for dtb: error %d\n",
34 			     map_ret);
35 		}
36 #endif
37 
38 		if (!map_ret) {
39 			/* Return if no device tree is detected */
40 			if (fdt_check_header(dtb) != 0) {
41 				NOTICE("Can't read DT at %p\n", dtb);
42 			} else {
43 				ret = fdt_open_into(dtb, dtb, XILINX_OF_BOARD_DTB_MAX_SIZE);
44 
45 				if (ret < 0) {
46 					ERROR("Invalid Device Tree at %p: error %d\n",
47 					      dtb, ret);
48 				} else {
49 
50 					if (dt_add_psci_node(dtb)) {
51 						WARN("Failed to add PSCI Device Tree node\n");
52 					}
53 
54 					if (dt_add_psci_cpu_enable_methods(dtb)) {
55 						WARN("Failed to add PSCI cpu enable methods in DT\n");
56 					}
57 
58 					/* Reserve memory used by Trusted Firmware. */
59 					ret = fdt_add_reserved_memory(dtb,
60 								     "tf-a",
61 								     BL31_BASE,
62 								     BL31_LIMIT
63 								     -
64 								     BL31_BASE);
65 					if (ret < 0) {
66 						WARN("Failed to add reserved memory nodes for BL31 to DT.\n");
67 					}
68 
69 					ret = fdt_pack(dtb);
70 					if (ret < 0) {
71 						WARN("Failed to pack dtb at %p: error %d\n",
72 						     dtb, ret);
73 					}
74 					flush_dcache_range((uintptr_t)dtb,
75 							   fdt_blob_size(dtb));
76 
77 					INFO("Changed device tree to advertise PSCI and reserved memories.\n");
78 
79 				}
80 			}
81 
82 		}
83 
84 
85 #if defined(PLAT_XLAT_TABLES_DYNAMIC)
86 		if (!map_ret) {
87 			ret = mmap_remove_dynamic_region((uintptr_t)dtb,
88 					 XILINX_OF_BOARD_DTB_MAX_SIZE);
89 			if (ret != 0) {
90 				WARN("Failed to remove dynamic region for dtb:error %d\n",
91 					ret);
92 			}
93 		}
94 #endif
95 	}
96 
97 #endif
98 }
99