xref: /openbmc/u-boot/env/fat.c (revision e23b19f4)
1 /*
2  * (c) Copyright 2011 by Tigris Elektronik GmbH
3  *
4  * Author:
5  *  Maximilian Schwerin <mvs@tigris.de>
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 
12 #include <command.h>
13 #include <environment.h>
14 #include <linux/stddef.h>
15 #include <malloc.h>
16 #include <memalign.h>
17 #include <search.h>
18 #include <errno.h>
19 #include <fat.h>
20 #include <mmc.h>
21 
22 #ifdef CONFIG_SPL_BUILD
23 /* TODO(sjg@chromium.org): Figure out why this is needed */
24 # if !defined(CONFIG_TARGET_AM335X_EVM) || defined(CONFIG_SPL_OS_BOOT)
25 #  define LOADENV
26 # endif
27 #else
28 # define LOADENV
29 # if defined(CONFIG_CMD_SAVEENV)
30 #  define CMD_SAVEENV
31 # endif
32 #endif
33 
34 DECLARE_GLOBAL_DATA_PTR;
35 
36 #ifdef CMD_SAVEENV
37 static int env_fat_save(void)
38 {
39 	env_t	env_new;
40 	struct blk_desc *dev_desc = NULL;
41 	disk_partition_t info;
42 	int dev, part;
43 	int err;
44 	loff_t size;
45 
46 	err = env_export(&env_new);
47 	if (err)
48 		return err;
49 
50 	part = blk_get_device_part_str(CONFIG_ENV_FAT_INTERFACE,
51 					CONFIG_ENV_FAT_DEVICE_AND_PART,
52 					&dev_desc, &info, 1);
53 	if (part < 0)
54 		return 1;
55 
56 	dev = dev_desc->devnum;
57 	if (fat_set_blk_dev(dev_desc, &info) != 0) {
58 		/*
59 		 * This printf is embedded in the messages from env_save that
60 		 * will calling it. The missing \n is intentional.
61 		 */
62 		printf("Unable to use %s %d:%d... ",
63 		       CONFIG_ENV_FAT_INTERFACE, dev, part);
64 		return 1;
65 	}
66 
67 	err = file_fat_write(CONFIG_ENV_FAT_FILE, (void *)&env_new, 0, sizeof(env_t),
68 			     &size);
69 	if (err == -1) {
70 		/*
71 		 * This printf is embedded in the messages from env_save that
72 		 * will calling it. The missing \n is intentional.
73 		 */
74 		printf("Unable to write \"%s\" from %s%d:%d... ",
75 			CONFIG_ENV_FAT_FILE, CONFIG_ENV_FAT_INTERFACE, dev, part);
76 		return 1;
77 	}
78 
79 	return 0;
80 }
81 #endif /* CMD_SAVEENV */
82 
83 #ifdef LOADENV
84 static int env_fat_load(void)
85 {
86 	ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE);
87 	struct blk_desc *dev_desc = NULL;
88 	disk_partition_t info;
89 	int dev, part;
90 	int err;
91 
92 	part = blk_get_device_part_str(CONFIG_ENV_FAT_INTERFACE,
93 					CONFIG_ENV_FAT_DEVICE_AND_PART,
94 					&dev_desc, &info, 1);
95 	if (part < 0)
96 		goto err_env_relocate;
97 
98 	dev = dev_desc->devnum;
99 	if (fat_set_blk_dev(dev_desc, &info) != 0) {
100 		/*
101 		 * This printf is embedded in the messages from env_save that
102 		 * will calling it. The missing \n is intentional.
103 		 */
104 		printf("Unable to use %s %d:%d... ",
105 		       CONFIG_ENV_FAT_INTERFACE, dev, part);
106 		goto err_env_relocate;
107 	}
108 
109 	err = file_fat_read(CONFIG_ENV_FAT_FILE, buf, CONFIG_ENV_SIZE);
110 	if (err == -1) {
111 		/*
112 		 * This printf is embedded in the messages from env_save that
113 		 * will calling it. The missing \n is intentional.
114 		 */
115 		printf("Unable to read \"%s\" from %s%d:%d... ",
116 			CONFIG_ENV_FAT_FILE, CONFIG_ENV_FAT_INTERFACE, dev, part);
117 		goto err_env_relocate;
118 	}
119 
120 	env_import(buf, 1);
121 	return 0;
122 
123 err_env_relocate:
124 	set_default_env(NULL);
125 
126 	return -EIO;
127 }
128 #endif /* LOADENV */
129 
130 U_BOOT_ENV_LOCATION(fat) = {
131 	.location	= ENVL_FAT,
132 	ENV_NAME("FAT")
133 #ifdef LOADENV
134 	.load		= env_fat_load,
135 #endif
136 #ifdef CMD_SAVEENV
137 	.save		= env_save_ptr(env_fat_save),
138 #endif
139 };
140