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 
16 #if defined(XILINX_OF_BOARD_DTB_ADDR)
17 
18 #define FIT_CONFS_PATH	"/configurations"
19 
is_fit_image(void * dtb)20 static uint8_t is_fit_image(void *dtb)
21 {
22 	int64_t confs_noffset;
23 	uint8_t status = 0;
24 
25 	confs_noffset = fdt_path_offset(dtb, FIT_CONFS_PATH);
26 	/*confs_noffset is only present on FIT image */
27 	if (confs_noffset < 0) {
28 		status = 0;
29 	} else {
30 		status = 1;
31 	}
32 
33 	return status;
34 }
35 
is_valid_dtb(void * fdt)36 int32_t is_valid_dtb(void *fdt)
37 {
38 	int32_t ret = 0;
39 
40 	if (fdt_check_header(fdt) != 0) {
41 		ERROR("Can't read DT at %p\n", fdt);
42 		ret = -FDT_ERR_NOTFOUND;
43 		goto error;
44 	}
45 
46 	ret = fdt_open_into(fdt, fdt, XILINX_OF_BOARD_DTB_MAX_SIZE);
47 	if (ret < 0) {
48 		ERROR("Invalid Device Tree at %p: error %d\n", fdt, ret);
49 		ret = -FDT_ERR_NOTFOUND;
50 		goto error;
51 	}
52 
53 	if (is_fit_image(fdt) != 0U) {
54 		WARN("FIT image detected, TF-A will not update DTB for DDR address space\n");
55 		ret = -FDT_ERR_NOTFOUND;
56 	}
57 error:
58 	return ret;
59 }
60 
add_mmap_dynamic_region(unsigned long long base_pa,uintptr_t base_va,size_t size,unsigned int attr)61 static int add_mmap_dynamic_region(unsigned long long base_pa, uintptr_t base_va,
62 			    size_t size, unsigned int attr)
63 {
64 	int ret = 0;
65 #if defined(PLAT_XLAT_TABLES_DYNAMIC)
66 	ret = mmap_add_dynamic_region(base_pa, base_va, size, attr);
67 	if (ret != 0) {
68 		WARN("Failed to add dynamic region for dtb: error %d\n",
69 		     ret);
70 	}
71 #endif
72 	return ret;
73 }
74 
remove_mmap_dynamic_region(uintptr_t base_va,size_t size)75 static int remove_mmap_dynamic_region(uintptr_t base_va, size_t size)
76 {
77 	int ret = 0;
78 #if defined(PLAT_XLAT_TABLES_DYNAMIC)
79 	ret = mmap_remove_dynamic_region(base_va, size);
80 	if (ret != 0) {
81 		WARN("Failed to remove dynamic region for dtb:error %d\n",
82 		     ret);
83 	}
84 #endif
85 	return ret;
86 }
87 #endif
88 
prepare_dtb(void)89 void prepare_dtb(void)
90 {
91 #if defined(XILINX_OF_BOARD_DTB_ADDR)
92 	void *dtb;
93 	int map_ret = 0;
94 	int ret = 0;
95 
96 	dtb = (void *)XILINX_OF_BOARD_DTB_ADDR;
97 
98 	if (!IS_TFA_IN_OCM(BL31_BASE)) {
99 
100 		map_ret = add_mmap_dynamic_region((unsigned long long)dtb,
101 						  (uintptr_t)dtb,
102 						  XILINX_OF_BOARD_DTB_MAX_SIZE,
103 						  MT_MEMORY | MT_RW | MT_NS);
104 		if (map_ret == 0) {
105 			/* Return if no device tree is detected */
106 			if (is_valid_dtb(dtb) == 0) {
107 				if (dt_add_psci_node(dtb)) {
108 					WARN("Failed to add PSCI Device Tree node\n");
109 				}
110 
111 				if (dt_add_psci_cpu_enable_methods(dtb)) {
112 					WARN("Failed to add PSCI cpu enable methods in DT\n");
113 				}
114 
115 				/* Reserve memory used by Trusted Firmware. */
116 				ret = fdt_add_reserved_memory(dtb, "tf-a",
117 							      BL31_BASE,
118 							      BL31_LIMIT - BL31_BASE);
119 				if (ret < 0) {
120 					WARN("Failed to add reserved memory nodes for BL31 to DT.\n");
121 				}
122 
123 				ret = fdt_pack(dtb);
124 				if (ret < 0) {
125 					WARN("Failed to pack dtb at %p: error %d\n", dtb, ret);
126 				}
127 				flush_dcache_range((uintptr_t)dtb, fdt_blob_size(dtb));
128 
129 				INFO("Changed device tree to advertise PSCI and reserved memories.\n");
130 			}
131 
132 			ret = remove_mmap_dynamic_region((uintptr_t)dtb,
133 							 XILINX_OF_BOARD_DTB_MAX_SIZE);
134 			if (ret != 0) {
135 				WARN("Failed to remove mmap dynamic regions.\n");
136 			}
137 		}
138 	}
139 #endif
140 }
141