xref: /openbmc/u-boot/disk/part_dos.c (revision 1a68faac) 
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2001
4  * Raymond Lo, lo@routefree.com
5  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
6  */
7 
8 /*
9  * Support for harddisk partitions.
10  *
11  * To be compatible with LinuxPPC and Apple we use the standard Apple
12  * SCSI disk partitioning scheme. For more information see:
13  * http://developer.apple.com/techpubs/mac/Devices/Devices-126.html#MARKER-14-92
14  */
15 
16 #include <common.h>
17 #include <command.h>
18 #include <ide.h>
19 #include <memalign.h>
20 #include "part_dos.h"
21 
22 #ifdef CONFIG_HAVE_BLOCK_DEVICE
23 
24 #define DOS_PART_DEFAULT_SECTOR 512
25 
26 /* Convert char[4] in little endian format to the host format integer
27  */
28 static inline unsigned int le32_to_int(unsigned char *le32)
29 {
30     return ((le32[3] << 24) +
31 	    (le32[2] << 16) +
32 	    (le32[1] << 8) +
33 	     le32[0]
34 	   );
35 }
36 
37 static inline int is_extended(int part_type)
38 {
39     return (part_type == 0x5 ||
40 	    part_type == 0xf ||
41 	    part_type == 0x85);
42 }
43 
44 static inline int is_bootable(dos_partition_t *p)
45 {
46 	return (p->sys_ind == 0xef) || (p->boot_ind == 0x80);
47 }
48 
49 static void print_one_part(dos_partition_t *p, lbaint_t ext_part_sector,
50 			   int part_num, unsigned int disksig)
51 {
52 	lbaint_t lba_start = ext_part_sector + le32_to_int (p->start4);
53 	lbaint_t lba_size  = le32_to_int (p->size4);
54 
55 	printf("%3d\t%-10" LBAFlength "u\t%-10" LBAFlength
56 		"u\t%08x-%02x\t%02x%s%s\n",
57 		part_num, lba_start, lba_size, disksig, part_num, p->sys_ind,
58 		(is_extended(p->sys_ind) ? " Extd" : ""),
59 		(is_bootable(p) ? " Boot" : ""));
60 }
61 
62 static int test_block_type(unsigned char *buffer)
63 {
64 	int slot;
65 	struct dos_partition *p;
66 
67 	if((buffer[DOS_PART_MAGIC_OFFSET + 0] != 0x55) ||
68 	    (buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) ) {
69 		return (-1);
70 	} /* no DOS Signature at all */
71 	p = (struct dos_partition *)&buffer[DOS_PART_TBL_OFFSET];
72 	for (slot = 0; slot < 3; slot++) {
73 		if (p->boot_ind != 0 && p->boot_ind != 0x80) {
74 			if (!slot &&
75 			    (strncmp((char *)&buffer[DOS_PBR_FSTYPE_OFFSET],
76 				     "FAT", 3) == 0 ||
77 			     strncmp((char *)&buffer[DOS_PBR32_FSTYPE_OFFSET],
78 				     "FAT32", 5) == 0)) {
79 				return DOS_PBR; /* is PBR */
80 			} else {
81 				return -1;
82 			}
83 		}
84 	}
85 	return DOS_MBR;	    /* Is MBR */
86 }
87 
88 
89 static int part_test_dos(struct blk_desc *dev_desc)
90 {
91 #ifndef CONFIG_SPL_BUILD
92 	ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, mbr, 1);
93 
94 	if (blk_dread(dev_desc, 0, 1, (ulong *)mbr) != 1)
95 		return -1;
96 
97 	if (test_block_type((unsigned char *)mbr) != DOS_MBR)
98 		return -1;
99 
100 	if (dev_desc->sig_type == SIG_TYPE_NONE &&
101 	    mbr->unique_mbr_signature != 0) {
102 		dev_desc->sig_type = SIG_TYPE_MBR;
103 		dev_desc->mbr_sig = mbr->unique_mbr_signature;
104 	}
105 #else
106 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
107 
108 	if (blk_dread(dev_desc, 0, 1, (ulong *)buffer) != 1)
109 		return -1;
110 
111 	if (test_block_type(buffer) != DOS_MBR)
112 		return -1;
113 #endif
114 
115 	return 0;
116 }
117 
118 /*  Print a partition that is relative to its Extended partition table
119  */
120 static void print_partition_extended(struct blk_desc *dev_desc,
121 				     lbaint_t ext_part_sector,
122 				     lbaint_t relative,
123 				     int part_num, unsigned int disksig)
124 {
125 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
126 	dos_partition_t *pt;
127 	int i;
128 
129 	if (blk_dread(dev_desc, ext_part_sector, 1, (ulong *)buffer) != 1) {
130 		printf ("** Can't read partition table on %d:" LBAFU " **\n",
131 			dev_desc->devnum, ext_part_sector);
132 		return;
133 	}
134 	i=test_block_type(buffer);
135 	if (i != DOS_MBR) {
136 		printf ("bad MBR sector signature 0x%02x%02x\n",
137 			buffer[DOS_PART_MAGIC_OFFSET],
138 			buffer[DOS_PART_MAGIC_OFFSET + 1]);
139 		return;
140 	}
141 
142 	if (!ext_part_sector)
143 		disksig = le32_to_int(&buffer[DOS_PART_DISKSIG_OFFSET]);
144 
145 	/* Print all primary/logical partitions */
146 	pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
147 	for (i = 0; i < 4; i++, pt++) {
148 		/*
149 		 * fdisk does not show the extended partitions that
150 		 * are not in the MBR
151 		 */
152 
153 		if ((pt->sys_ind != 0) &&
154 		    (ext_part_sector == 0 || !is_extended (pt->sys_ind)) ) {
155 			print_one_part(pt, ext_part_sector, part_num, disksig);
156 		}
157 
158 		/* Reverse engr the fdisk part# assignment rule! */
159 		if ((ext_part_sector == 0) ||
160 		    (pt->sys_ind != 0 && !is_extended (pt->sys_ind)) ) {
161 			part_num++;
162 		}
163 	}
164 
165 	/* Follows the extended partitions */
166 	pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
167 	for (i = 0; i < 4; i++, pt++) {
168 		if (is_extended (pt->sys_ind)) {
169 			lbaint_t lba_start
170 				= le32_to_int (pt->start4) + relative;
171 
172 			print_partition_extended(dev_desc, lba_start,
173 				ext_part_sector == 0  ? lba_start : relative,
174 				part_num, disksig);
175 		}
176 	}
177 
178 	return;
179 }
180 
181 
182 /*  Print a partition that is relative to its Extended partition table
183  */
184 static int part_get_info_extended(struct blk_desc *dev_desc,
185 				  lbaint_t ext_part_sector, lbaint_t relative,
186 				  int part_num, int which_part,
187 				  disk_partition_t *info, unsigned int disksig)
188 {
189 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
190 	dos_partition_t *pt;
191 	int i;
192 	int dos_type;
193 
194 	if (blk_dread(dev_desc, ext_part_sector, 1, (ulong *)buffer) != 1) {
195 		printf ("** Can't read partition table on %d:" LBAFU " **\n",
196 			dev_desc->devnum, ext_part_sector);
197 		return -1;
198 	}
199 	if (buffer[DOS_PART_MAGIC_OFFSET] != 0x55 ||
200 		buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) {
201 		printf ("bad MBR sector signature 0x%02x%02x\n",
202 			buffer[DOS_PART_MAGIC_OFFSET],
203 			buffer[DOS_PART_MAGIC_OFFSET + 1]);
204 		return -1;
205 	}
206 
207 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
208 	if (!ext_part_sector)
209 		disksig = le32_to_int(&buffer[DOS_PART_DISKSIG_OFFSET]);
210 #endif
211 
212 	/* Print all primary/logical partitions */
213 	pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
214 	for (i = 0; i < 4; i++, pt++) {
215 		/*
216 		 * fdisk does not show the extended partitions that
217 		 * are not in the MBR
218 		 */
219 		if (((pt->boot_ind & ~0x80) == 0) &&
220 		    (pt->sys_ind != 0) &&
221 		    (part_num == which_part) &&
222 		    (ext_part_sector == 0 || is_extended(pt->sys_ind) == 0)) {
223 			info->blksz = DOS_PART_DEFAULT_SECTOR;
224 			info->start = (lbaint_t)(ext_part_sector +
225 					le32_to_int(pt->start4));
226 			info->size  = (lbaint_t)le32_to_int(pt->size4);
227 			part_set_generic_name(dev_desc, part_num,
228 					      (char *)info->name);
229 			/* sprintf(info->type, "%d, pt->sys_ind); */
230 			strcpy((char *)info->type, "U-Boot");
231 			info->bootable = is_bootable(pt);
232 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
233 			sprintf(info->uuid, "%08x-%02x", disksig, part_num);
234 #endif
235 			info->sys_ind = pt->sys_ind;
236 			return 0;
237 		}
238 
239 		/* Reverse engr the fdisk part# assignment rule! */
240 		if ((ext_part_sector == 0) ||
241 		    (pt->sys_ind != 0 && !is_extended (pt->sys_ind)) ) {
242 			part_num++;
243 		}
244 	}
245 
246 	/* Follows the extended partitions */
247 	pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
248 	for (i = 0; i < 4; i++, pt++) {
249 		if (is_extended (pt->sys_ind)) {
250 			lbaint_t lba_start
251 				= le32_to_int (pt->start4) + relative;
252 
253 			return part_get_info_extended(dev_desc, lba_start,
254 				 ext_part_sector == 0 ? lba_start : relative,
255 				 part_num, which_part, info, disksig);
256 		}
257 	}
258 
259 	/* Check for DOS PBR if no partition is found */
260 	dos_type = test_block_type(buffer);
261 
262 	if (dos_type == DOS_PBR) {
263 		info->start = 0;
264 		info->size = dev_desc->lba;
265 		info->blksz = DOS_PART_DEFAULT_SECTOR;
266 		info->bootable = 0;
267 		strcpy((char *)info->type, "U-Boot");
268 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
269 		info->uuid[0] = 0;
270 #endif
271 		return 0;
272 	}
273 
274 	return -1;
275 }
276 
277 void part_print_dos(struct blk_desc *dev_desc)
278 {
279 	printf("Part\tStart Sector\tNum Sectors\tUUID\t\tType\n");
280 	print_partition_extended(dev_desc, 0, 0, 1, 0);
281 }
282 
283 int part_get_info_dos(struct blk_desc *dev_desc, int part,
284 		      disk_partition_t *info)
285 {
286 	return part_get_info_extended(dev_desc, 0, 0, 1, part, info, 0);
287 }
288 
289 int is_valid_dos_buf(void *buf)
290 {
291 	return test_block_type(buf) == DOS_MBR ? 0 : -1;
292 }
293 
294 int write_mbr_partition(struct blk_desc *dev_desc, void *buf)
295 {
296 	if (is_valid_dos_buf(buf))
297 		return -1;
298 
299 	/* write MBR */
300 	if (blk_dwrite(dev_desc, 0, 1, buf) != 1) {
301 		printf("%s: failed writing '%s' (1 blks at 0x0)\n",
302 		       __func__, "MBR");
303 		return 1;
304 	}
305 
306 	return 0;
307 }
308 
309 U_BOOT_PART_TYPE(dos) = {
310 	.name		= "DOS",
311 	.part_type	= PART_TYPE_DOS,
312 	.max_entries	= DOS_ENTRY_NUMBERS,
313 	.get_info	= part_get_info_ptr(part_get_info_dos),
314 	.print		= part_print_ptr(part_print_dos),
315 	.test		= part_test_dos,
316 };
317 
318 #endif
319