1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2020 Western Digital Corporation or its affiliates
4  *
5  */
6 
7 #define LOG_CATEGORY LOGC_ARCH
8 
9 #include <fdt_support.h>
10 #include <log.h>
11 #include <mapmem.h>
12 #include <asm/global_data.h>
13 
14 DECLARE_GLOBAL_DATA_PTR;
15 
16 /**
17  * riscv_fdt_copy_resv_mem_node() - Copy reserve memory node entry
18  * @src: Pointer to the source device tree from which reserved memory node
19  *	 needs to be copied.
20  * @dst: Pointer to the destination device tree to which reserved memory node
21  *	 needs to be copied.
22  *
23  * Return: 0 on success or if source doesn't have reserved memory node.
24  *	   Error if copy process failed.
25  */
riscv_fdt_copy_resv_mem_node(const void * src,void * dst)26 int riscv_fdt_copy_resv_mem_node(const void *src, void *dst)
27 {
28 	u32 phandle;
29 	struct fdt_memory pmp_mem;
30 	fdt_addr_t addr;
31 	fdt_size_t size;
32 	int offset, node, err, rmem_offset;
33 	char basename[32] = {0};
34 	int bname_len;
35 	int max_len = sizeof(basename);
36 	const char *name;
37 	char *temp;
38 
39 	offset = fdt_path_offset(src, "/reserved-memory");
40 	if (offset < 0) {
41 		log_debug("No reserved memory region found in source FDT\n");
42 		return 0;
43 	}
44 
45 	/*
46 	 * Extend the FDT by the following estimated size:
47 	 *
48 	 * Each PMP memory region entry occupies 64 bytes.
49 	 * With 16 PMP memory regions we need 64 * 16 = 1024 bytes.
50 	 */
51 	err = fdt_open_into(dst, dst, fdt_totalsize(dst) + 1024);
52 	if (err < 0) {
53 		printf("Device Tree can't be expanded to accommodate new node");
54 		return err;
55 	}
56 
57 	fdt_for_each_subnode(node, src, offset) {
58 		name = fdt_get_name(src, node, NULL);
59 
60 		addr = fdtdec_get_addr_size_auto_parent(src, offset, node,
61 							"reg", 0, &size,
62 							false);
63 		if (addr == FDT_ADDR_T_NONE) {
64 			log_debug("failed to read address/size for %s\n", name);
65 			continue;
66 		}
67 		strncpy(basename, name, max_len);
68 		temp = strchr(basename, '@');
69 		if (temp) {
70 			bname_len = strnlen(basename, max_len) - strnlen(temp,
71 								       max_len);
72 			*(basename + bname_len) = '\0';
73 		}
74 		pmp_mem.start = addr;
75 		pmp_mem.end = addr + size - 1;
76 		err = fdtdec_add_reserved_memory(dst, basename, &pmp_mem,
77 						 NULL, 0, &phandle, 0);
78 		if (err < 0 && err != -FDT_ERR_EXISTS) {
79 			log_err("failed to add reserved memory: %d\n", err);
80 			return err;
81 		}
82 		if (fdt_getprop(src, node, "no-map", NULL)) {
83 			rmem_offset = fdt_node_offset_by_phandle(dst, phandle);
84 			fdt_setprop_empty(dst, rmem_offset, "no-map");
85 		}
86 	}
87 
88 	return 0;
89 }
90 
91 /**
92  * riscv_board_reserved_mem_fixup() - Fix up reserved memory node for a board
93  * @fdt: Pointer to the device tree in which reserved memory node needs to be
94  *	 added.
95  *
96  * In RISC-V, any board needs to copy the reserved memory node from the device
97  * tree provided by the firmware to the device tree used by U-Boot. This is a
98  * common function that individual board fixup functions can invoke.
99  *
100  * Return: 0 on success or error otherwise.
101  */
riscv_board_reserved_mem_fixup(void * fdt)102 int riscv_board_reserved_mem_fixup(void *fdt)
103 {
104 	int err;
105 	void *src_fdt_addr;
106 
107 	src_fdt_addr = map_sysmem(gd->arch.firmware_fdt_addr, 0);
108 
109 	/* avoid the copy if we are using the same device tree */
110 	if (src_fdt_addr == fdt)
111 		return 0;
112 
113 	err = riscv_fdt_copy_resv_mem_node(src_fdt_addr, fdt);
114 	if (err < 0)
115 		return err;
116 
117 	return 0;
118 }
119 
120 #ifdef CONFIG_OF_BOARD_FIXUP
board_fix_fdt(void * fdt)121 int board_fix_fdt(void *fdt)
122 {
123 	int err;
124 
125 	err = riscv_board_reserved_mem_fixup(fdt);
126 	if (err < 0) {
127 		log_err("failed to fixup DT for reserved memory: %d\n", err);
128 		return err;
129 	}
130 
131 	return 0;
132 }
133 #endif
134 
arch_fixup_fdt(void * blob)135 int arch_fixup_fdt(void *blob)
136 {
137 	int err;
138 #ifdef CONFIG_EFI_LOADER
139 	u32 size;
140 	int chosen_offset;
141 
142 	size = fdt_totalsize(blob);
143 	err  = fdt_open_into(blob, blob, size + 32);
144 	if (err < 0) {
145 		log_err("Device-tree can't be expanded to accommodate new node\n");
146 		return err;
147 	}
148 	chosen_offset = fdt_path_offset(blob, "/chosen");
149 	if (chosen_offset < 0) {
150 		chosen_offset = fdt_add_subnode(blob, 0, "chosen");
151 		if (chosen_offset < 0) {
152 			log_err("chosen node cannot be added\n");
153 			return chosen_offset;
154 		}
155 	}
156 	/* Overwrite the boot-hartid as U-Boot is the last stage BL */
157 	err = fdt_setprop_u32(blob, chosen_offset, "boot-hartid",
158 			      gd->arch.boot_hart);
159 	if (err < 0)
160 		return log_msg_ret("could not set boot-hartid", err);
161 #endif
162 
163 	/* Copy the reserved-memory node to the DT used by OS */
164 	err = riscv_fdt_copy_resv_mem_node(gd->fdt_blob, blob);
165 	if (err < 0)
166 		return err;
167 
168 	return 0;
169 }
170