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 #include <command.h>
11 #include <env.h>
12 #include <env_internal.h>
13 #include <part.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 #include <asm/cache.h>
21 #include <linux/stddef.h>
22 
23 #ifdef CONFIG_SPL_BUILD
24 /* TODO(sjg@chromium.org): Figure out why this is needed */
25 # if !defined(CONFIG_TARGET_AM335X_EVM) || defined(CONFIG_SPL_OS_BOOT)
26 #  define LOADENV
27 # endif
28 #else
29 # define LOADENV
30 #endif
31 
env_fat_device_and_part(void)32 static char *env_fat_device_and_part(void)
33 {
34 #ifdef CONFIG_MMC
35 	static char *part_str;
36 
37 	if (!part_str) {
38 		part_str = CONFIG_ENV_FAT_DEVICE_AND_PART;
39 		if (!strcmp(CONFIG_ENV_FAT_INTERFACE, "mmc") && part_str[0] == ':') {
40 			part_str = "0" CONFIG_ENV_FAT_DEVICE_AND_PART;
41 			part_str[0] += mmc_get_env_dev();
42 		}
43 	}
44 
45 	return part_str;
46 #else
47 	return CONFIG_ENV_FAT_DEVICE_AND_PART;
48 #endif
49 }
50 
env_fat_save(void)51 static int env_fat_save(void)
52 {
53 	env_t __aligned(ARCH_DMA_MINALIGN) env_new;
54 	struct blk_desc *dev_desc = NULL;
55 	struct disk_partition info;
56 	int dev, part;
57 	int err;
58 	loff_t size;
59 
60 	err = env_export(&env_new);
61 	if (err)
62 		return err;
63 
64 	part = blk_get_device_part_str(CONFIG_ENV_FAT_INTERFACE,
65 					env_fat_device_and_part(),
66 					&dev_desc, &info, 1);
67 	if (part < 0)
68 		return 1;
69 
70 	dev = dev_desc->devnum;
71 	if (fat_set_blk_dev(dev_desc, &info) != 0) {
72 		/*
73 		 * This printf is embedded in the messages from env_save that
74 		 * will calling it. The missing \n is intentional.
75 		 */
76 		printf("Unable to use %s %d:%d... ",
77 		       CONFIG_ENV_FAT_INTERFACE, dev, part);
78 		return 1;
79 	}
80 
81 	err = file_fat_write(CONFIG_ENV_FAT_FILE, (void *)&env_new, 0, sizeof(env_t),
82 			     &size);
83 	if (err == -1) {
84 		/*
85 		 * This printf is embedded in the messages from env_save that
86 		 * will calling it. The missing \n is intentional.
87 		 */
88 		printf("Unable to write \"%s\" from %s%d:%d... ",
89 			CONFIG_ENV_FAT_FILE, CONFIG_ENV_FAT_INTERFACE, dev, part);
90 		return 1;
91 	}
92 
93 	return 0;
94 }
95 
96 #ifdef LOADENV
env_fat_load(void)97 static int env_fat_load(void)
98 {
99 	ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE);
100 	struct blk_desc *dev_desc = NULL;
101 	struct disk_partition info;
102 	int dev, part;
103 	int err;
104 
105 #ifdef CONFIG_MMC
106 	if (!strcmp(CONFIG_ENV_FAT_INTERFACE, "mmc"))
107 		mmc_initialize(NULL);
108 #endif
109 
110 	part = blk_get_device_part_str(CONFIG_ENV_FAT_INTERFACE,
111 					env_fat_device_and_part(),
112 					&dev_desc, &info, 1);
113 	if (part < 0)
114 		goto err_env_relocate;
115 
116 	dev = dev_desc->devnum;
117 	if (fat_set_blk_dev(dev_desc, &info) != 0) {
118 		/*
119 		 * This printf is embedded in the messages from env_save that
120 		 * will calling it. The missing \n is intentional.
121 		 */
122 		printf("Unable to use %s %d:%d... ",
123 		       CONFIG_ENV_FAT_INTERFACE, dev, part);
124 		goto err_env_relocate;
125 	}
126 
127 	err = file_fat_read(CONFIG_ENV_FAT_FILE, buf, CONFIG_ENV_SIZE);
128 	if (err == -1) {
129 		/*
130 		 * This printf is embedded in the messages from env_save that
131 		 * will calling it. The missing \n is intentional.
132 		 */
133 		printf("Unable to read \"%s\" from %s%d:%d... ",
134 			CONFIG_ENV_FAT_FILE, CONFIG_ENV_FAT_INTERFACE, dev, part);
135 		goto err_env_relocate;
136 	}
137 
138 	return env_import(buf, 1, H_EXTERNAL);
139 
140 err_env_relocate:
141 	env_set_default(NULL, 0);
142 
143 	return -EIO;
144 }
145 #endif /* LOADENV */
146 
147 U_BOOT_ENV_LOCATION(fat) = {
148 	.location	= ENVL_FAT,
149 	ENV_NAME("FAT")
150 #ifdef LOADENV
151 	.load		= env_fat_load,
152 #endif
153 	.save		= ENV_SAVE_PTR(env_fat_save),
154 };
155