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
14DECLARE_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 */
26int 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 */
102int 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
121int 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
135int 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");
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