xref: /openbmc/u-boot/env/fat.c (revision fd0bc623)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (c) Copyright 2011 by Tigris Elektronik GmbH
4  *
5  * Author:
6  *  Maximilian Schwerin <mvs@tigris.de>
7  */
8 
9 #include <common.h>
10 
11 #include <command.h>
12 #include <environment.h>
13 #include <linux/stddef.h>
14 #include <malloc.h>
15 #include <memalign.h>
16 #include <search.h>
17 #include <errno.h>
18 #include <fat.h>
19 #include <mmc.h>
20 
21 #ifdef CONFIG_SPL_BUILD
22 /* TODO(sjg@chromium.org): Figure out why this is needed */
23 # if !defined(CONFIG_TARGET_AM335X_EVM) || defined(CONFIG_SPL_OS_BOOT)
24 #  define LOADENV
25 # endif
26 #else
27 # define LOADENV
28 # if defined(CONFIG_CMD_SAVEENV)
29 #  define CMD_SAVEENV
30 # endif
31 #endif
32 
33 #ifdef CMD_SAVEENV
34 static int env_fat_save(void)
35 {
36 	env_t __aligned(ARCH_DMA_MINALIGN) env_new;
37 	struct blk_desc *dev_desc = NULL;
38 	disk_partition_t info;
39 	int dev, part;
40 	int err;
41 	loff_t size;
42 
43 	err = env_export(&env_new);
44 	if (err)
45 		return err;
46 
47 	part = blk_get_device_part_str(CONFIG_ENV_FAT_INTERFACE,
48 					CONFIG_ENV_FAT_DEVICE_AND_PART,
49 					&dev_desc, &info, 1);
50 	if (part < 0)
51 		return 1;
52 
53 	dev = dev_desc->devnum;
54 	if (fat_set_blk_dev(dev_desc, &info) != 0) {
55 		/*
56 		 * This printf is embedded in the messages from env_save that
57 		 * will calling it. The missing \n is intentional.
58 		 */
59 		printf("Unable to use %s %d:%d... ",
60 		       CONFIG_ENV_FAT_INTERFACE, dev, part);
61 		return 1;
62 	}
63 
64 	err = file_fat_write(CONFIG_ENV_FAT_FILE, (void *)&env_new, 0, sizeof(env_t),
65 			     &size);
66 	if (err == -1) {
67 		/*
68 		 * This printf is embedded in the messages from env_save that
69 		 * will calling it. The missing \n is intentional.
70 		 */
71 		printf("Unable to write \"%s\" from %s%d:%d... ",
72 			CONFIG_ENV_FAT_FILE, CONFIG_ENV_FAT_INTERFACE, dev, part);
73 		return 1;
74 	}
75 
76 	return 0;
77 }
78 #endif /* CMD_SAVEENV */
79 
80 #ifdef LOADENV
81 static int env_fat_load(void)
82 {
83 	ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE);
84 	struct blk_desc *dev_desc = NULL;
85 	disk_partition_t info;
86 	int dev, part;
87 	int err;
88 
89 #ifdef CONFIG_MMC
90 	if (!strcmp(CONFIG_ENV_FAT_INTERFACE, "mmc"))
91 		mmc_initialize(NULL);
92 #endif
93 
94 	part = blk_get_device_part_str(CONFIG_ENV_FAT_INTERFACE,
95 					CONFIG_ENV_FAT_DEVICE_AND_PART,
96 					&dev_desc, &info, 1);
97 	if (part < 0)
98 		goto err_env_relocate;
99 
100 	dev = dev_desc->devnum;
101 	if (fat_set_blk_dev(dev_desc, &info) != 0) {
102 		/*
103 		 * This printf is embedded in the messages from env_save that
104 		 * will calling it. The missing \n is intentional.
105 		 */
106 		printf("Unable to use %s %d:%d... ",
107 		       CONFIG_ENV_FAT_INTERFACE, dev, part);
108 		goto err_env_relocate;
109 	}
110 
111 	err = file_fat_read(CONFIG_ENV_FAT_FILE, buf, CONFIG_ENV_SIZE);
112 	if (err == -1) {
113 		/*
114 		 * This printf is embedded in the messages from env_save that
115 		 * will calling it. The missing \n is intentional.
116 		 */
117 		printf("Unable to read \"%s\" from %s%d:%d... ",
118 			CONFIG_ENV_FAT_FILE, CONFIG_ENV_FAT_INTERFACE, dev, part);
119 		goto err_env_relocate;
120 	}
121 
122 	return env_import(buf, 1);
123 
124 err_env_relocate:
125 	set_default_env(NULL, 0);
126 
127 	return -EIO;
128 }
129 #endif /* LOADENV */
130 
131 U_BOOT_ENV_LOCATION(fat) = {
132 	.location	= ENVL_FAT,
133 	ENV_NAME("FAT")
134 #ifdef LOADENV
135 	.load		= env_fat_load,
136 #endif
137 #ifdef CMD_SAVEENV
138 	.save		= env_save_ptr(env_fat_save),
139 #endif
140 };
141