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 <common.h>
10 #include <fdt_support.h>
11 #include <log.h>
12 #include <mapmem.h>
13 #include <asm/global_data.h>
14 
15 DECLARE_GLOBAL_DATA_PTR;
16 
17 /**
18  * riscv_fdt_copy_resv_mem_node() - Copy reserve memory node entry
19  * @src: Pointer to the source device tree from which reserved memory node
20  *	 needs to be copied.
21  * @dst: Pointer to the destination device tree to which reserved memory node
22  *	 needs to be copied.
23  *
24  * Return: 0 on success or if source doesn't have reserved memory node.
25  *	   Error if copy process failed.
26  */
riscv_fdt_copy_resv_mem_node(const void * src,void * dst)27 int riscv_fdt_copy_resv_mem_node(const void *src, void *dst)
28 {
29 	u32 phandle;
30 	struct fdt_memory pmp_mem;
31 	fdt_addr_t addr;
32 	fdt_size_t size;
33 	int offset, node, err, rmem_offset;
34 	char basename[32] = {0};
35 	int bname_len;
36 	int max_len = sizeof(basename);
37 	const char *name;
38 	char *temp;
39 
40 	offset = fdt_path_offset(src, "/reserved-memory");
41 	if (offset < 0) {
42 		log_debug("No reserved memory region found in source FDT\n");
43 		return 0;
44 	}
45 
46 	/*
47 	 * Extend the FDT by the following estimated size:
48 	 *
49 	 * Each PMP memory region entry occupies 64 bytes.
50 	 * With 16 PMP memory regions we need 64 * 16 = 1024 bytes.
51 	 */
52 	err = fdt_open_into(dst, dst, fdt_totalsize(dst) + 1024);
53 	if (err < 0) {
54 		printf("Device Tree can't be expanded to accommodate new node");
55 		return err;
56 	}
57 
58 	fdt_for_each_subnode(node, src, offset) {
59 		name = fdt_get_name(src, node, NULL);
60 
61 		addr = fdtdec_get_addr_size_auto_parent(src, offset, node,
62 							"reg", 0, &size,
63 							false);
64 		if (addr == FDT_ADDR_T_NONE) {
65 			log_debug("failed to read address/size for %s\n", name);
66 			continue;
67 		}
68 		strncpy(basename, name, max_len);
69 		temp = strchr(basename, '@');
70 		if (temp) {
71 			bname_len = strnlen(basename, max_len) - strnlen(temp,
72 								       max_len);
73 			*(basename + bname_len) = '\0';
74 		}
75 		pmp_mem.start = addr;
76 		pmp_mem.end = addr + size - 1;
77 		err = fdtdec_add_reserved_memory(dst, basename, &pmp_mem,
78 						 NULL, 0, &phandle, 0);
79 		if (err < 0 && err != -FDT_ERR_EXISTS) {
80 			log_err("failed to add reserved memory: %d\n", err);
81 			return err;
82 		}
83 		if (fdt_getprop(src, node, "no-map", NULL)) {
84 			rmem_offset = fdt_node_offset_by_phandle(dst, phandle);
85 			fdt_setprop_empty(dst, rmem_offset, "no-map");
86 		}
87 	}
88 
89 	return 0;
90 }
91 
92 /**
93  * riscv_board_reserved_mem_fixup() - Fix up reserved memory node for a board
94  * @fdt: Pointer to the device tree in which reserved memory node needs to be
95  *	 added.
96  *
97  * In RISC-V, any board needs to copy the reserved memory node from the device
98  * tree provided by the firmware to the device tree used by U-Boot. This is a
99  * common function that individual board fixup functions can invoke.
100  *
101  * Return: 0 on success or error otherwise.
102  */
riscv_board_reserved_mem_fixup(void * fdt)103 int riscv_board_reserved_mem_fixup(void *fdt)
104 {
105 	int err;
106 	void *src_fdt_addr;
107 
108 	src_fdt_addr = map_sysmem(gd->arch.firmware_fdt_addr, 0);
109 
110 	/* avoid the copy if we are using the same device tree */
111 	if (src_fdt_addr == fdt)
112 		return 0;
113 
114 	err = riscv_fdt_copy_resv_mem_node(src_fdt_addr, fdt);
115 	if (err < 0)
116 		return err;
117 
118 	return 0;
119 }
120 
121 #ifdef CONFIG_OF_BOARD_FIXUP
board_fix_fdt(void * fdt)122 int board_fix_fdt(void *fdt)
123 {
124 	int err;
125 
126 	err = riscv_board_reserved_mem_fixup(fdt);
127 	if (err < 0) {
128 		log_err("failed to fixup DT for reserved memory: %d\n", err);
129 		return err;
130 	}
131 
132 	return 0;
133 }
134 #endif
135 
arch_fixup_fdt(void * blob)136 int arch_fixup_fdt(void *blob)
137 {
138 	int err;
139 #ifdef CONFIG_EFI_LOADER
140 	u32 size;
141 	int chosen_offset;
142 
143 	size = fdt_totalsize(blob);
144 	err  = fdt_open_into(blob, blob, size + 32);
145 	if (err < 0) {
146 		log_err("Device Tree can't be expanded to accommodate new node");
147 		return err;
148 	}
149 	chosen_offset = fdt_path_offset(blob, "/chosen");
150 	if (chosen_offset < 0) {
151 		chosen_offset = fdt_add_subnode(blob, 0, "chosen");
152 		if (chosen_offset < 0) {
153 			log_err("chosen node cannot be added\n");
154 			return chosen_offset;
155 		}
156 	}
157 	/* Overwrite the boot-hartid as U-Boot is the last stage BL */
158 	err = fdt_setprop_u32(blob, chosen_offset, "boot-hartid",
159 			      gd->arch.boot_hart);
160 	if (err < 0)
161 		return log_msg_ret("could not set boot-hartid", err);
162 #endif
163 
164 	/* Copy the reserved-memory node to the DT used by OS */
165 	err = riscv_fdt_copy_resv_mem_node(gd->fdt_blob, blob);
166 	if (err < 0)
167 		return err;
168 
169 	return 0;
170 }
171