1------------------- 2UBI usage in U-Boot 3------------------- 4 5UBI support in U-Boot is broken down into five separate commands. 6The first is the ubi command, which has six subcommands: 7 8=> help ubi 9ubi - ubi commands 10 11Usage: 12ubi part [part] [offset] 13 - Show or set current partition (with optional VID header offset) 14ubi info [l[ayout]] - Display volume and ubi layout information 15ubi create[vol] volume [size] [type] - create volume name with size 16ubi write[vol] address volume size - Write volume from address with size 17ubi write.part address volume size [fullsize] 18 - Write part of a volume from address 19ubi read[vol] address volume [size] - Read volume to address with size 20ubi remove[vol] volume - Remove volume 21[Legends] 22 volume: character name 23 size: specified in bytes 24 type: s[tatic] or d[ynamic] (default=dynamic) 25 26 27The first command that is needed to be issues is "ubi part" to connect 28one mtd partition to the UBI subsystem. This command will either create 29a new UBI device on the requested MTD partition. Or it will attach a 30previously created UBI device. The other UBI commands will only work 31when such a UBI device is attached (via "ubi part"). Here an example: 32 33=> mtdparts 34 35device nor0 <1fc000000.nor_flash>, # parts = 6 36 #: name size offset mask_flags 37 0: kernel 0x00200000 0x00000000 0 38 1: dtb 0x00040000 0x00200000 0 39 2: root 0x00200000 0x00240000 0 40 3: user 0x01ac0000 0x00440000 0 41 4: env 0x00080000 0x01f00000 0 42 5: u-boot 0x00080000 0x01f80000 0 43 44active partition: nor0,0 - (kernel) 0x00200000 @ 0x00000000 45 46defaults: 47mtdids : nor0=1fc000000.nor_flash 48mtdparts: mtdparts=1fc000000.nor_flash:2m(kernel),256k(dtb),2m(root),27392k(user),512k(env),512k(u-boot) 49 50=> ubi part root 51Creating 1 MTD partitions on "nor0": 520x000000240000-0x000000440000 : "mtd=2" 53UBI: attaching mtd1 to ubi0 54UBI: physical eraseblock size: 262144 bytes (256 KiB) 55UBI: logical eraseblock size: 262016 bytes 56UBI: smallest flash I/O unit: 1 57UBI: VID header offset: 64 (aligned 64) 58UBI: data offset: 128 59UBI: attached mtd1 to ubi0 60UBI: MTD device name: "mtd=2" 61UBI: MTD device size: 2 MiB 62UBI: number of good PEBs: 8 63UBI: number of bad PEBs: 0 64UBI: max. allowed volumes: 128 65UBI: wear-leveling threshold: 4096 66UBI: number of internal volumes: 1 67UBI: number of user volumes: 1 68UBI: available PEBs: 0 69UBI: total number of reserved PEBs: 8 70UBI: number of PEBs reserved for bad PEB handling: 0 71UBI: max/mean erase counter: 2/1 72 73 74Now that the UBI device is attached, this device can be modified 75using the following commands: 76 77ubi info Display volume and ubi layout information 78ubi createvol Create UBI volume on UBI device 79ubi removevol Remove UBI volume from UBI device 80ubi read Read data from UBI volume to memory 81ubi write Write data from memory to UBI volume 82ubi write.part Write data from memory to UBI volume, in parts 83 84 85Here a few examples on the usage: 86 87=> ubi create testvol 88Creating dynamic volume testvol of size 1048064 89 90=> ubi info l 91UBI: volume information dump: 92UBI: vol_id 0 93UBI: reserved_pebs 4 94UBI: alignment 1 95UBI: data_pad 0 96UBI: vol_type 3 97UBI: name_len 7 98UBI: usable_leb_size 262016 99UBI: used_ebs 4 100UBI: used_bytes 1048064 101UBI: last_eb_bytes 262016 102UBI: corrupted 0 103UBI: upd_marker 0 104UBI: name testvol 105 106UBI: volume information dump: 107UBI: vol_id 2147479551 108UBI: reserved_pebs 2 109UBI: alignment 1 110UBI: data_pad 0 111UBI: vol_type 3 112UBI: name_len 13 113UBI: usable_leb_size 262016 114UBI: used_ebs 2 115UBI: used_bytes 524032 116UBI: last_eb_bytes 2 117UBI: corrupted 0 118UBI: upd_marker 0 119UBI: name layout volume 120 121=> ubi info 122UBI: MTD device name: "mtd=2" 123UBI: MTD device size: 2 MiB 124UBI: physical eraseblock size: 262144 bytes (256 KiB) 125UBI: logical eraseblock size: 262016 bytes 126UBI: number of good PEBs: 8 127UBI: number of bad PEBs: 0 128UBI: smallest flash I/O unit: 1 129UBI: VID header offset: 64 (aligned 64) 130UBI: data offset: 128 131UBI: max. allowed volumes: 128 132UBI: wear-leveling threshold: 4096 133UBI: number of internal volumes: 1 134UBI: number of user volumes: 1 135UBI: available PEBs: 0 136UBI: total number of reserved PEBs: 8 137UBI: number of PEBs reserved for bad PEB handling: 0 138UBI: max/mean erase counter: 4/1 139 140=> ubi write 800000 testvol 80000 141Volume "testvol" found at volume id 0 142 143=> ubi read 900000 testvol 80000 144Volume testvol found at volume id 0 145read 524288 bytes from volume 0 to 900000(buf address) 146 147=> cmp.b 800000 900000 80000 148Total of 524288 bytes were the same 149 150 151Next, the ubifsmount command allows you to access filesystems on the 152UBI partition which has been attached with the ubi part command: 153 154=> help ubifsmount 155ubifsmount - mount UBIFS volume 156 157Usage: 158ubifsmount <volume-name> 159 - mount 'volume-name' volume 160 161For example: 162 163=> ubifsmount ubi0:recovery 164UBIFS: mounted UBI device 0, volume 0, name "recovery" 165UBIFS: mounted read-only 166UBIFS: file system size: 46473216 bytes (45384 KiB, 44 MiB, 366 LEBs) 167UBIFS: journal size: 6348800 bytes (6200 KiB, 6 MiB, 50 LEBs) 168UBIFS: media format: w4/r0 (latest is w4/r0) 169UBIFS: default compressor: LZO 170UBIFS: reserved for root: 0 bytes (0 KiB) 171 172Note that unlike Linux, U-Boot can only have one active UBI partition 173at a time, which can be referred to as ubi0, and must be supplied along 174with the name of the filesystem you are mounting. 175 176 177Once a UBI filesystem has been mounted, the ubifsls command allows you 178to list the contents of a directory in the filesystem: 179 180 181=> help ubifsls 182ubifsls - list files in a directory 183 184Usage: 185ubifsls [directory] 186 - list files in a 'directory' (default '/') 187 188For example: 189 190=> ubifsls 191 17442 Thu Jan 01 02:57:38 1970 imx28-evk.dtb 192 2998146 Thu Jan 01 02:57:43 1970 zImage 193 194 195And the ubifsload command allows you to load a file from a UBI 196filesystem: 197 198 199=> help ubifsload 200ubifsload - load file from an UBIFS filesystem 201 202Usage: 203ubifsload <addr> <filename> [bytes] 204 - load file 'filename' to address 'addr' 205 206For example: 207 208=> ubifsload ${loadaddr} zImage 209Loading file 'zImage' to addr 0x42000000 with size 2998146 (0x002dbf82)... 210Done 211 212 213Finally, you can unmount the UBI filesystem with the ubifsumount 214command: 215 216=> help ubifsumount 217ubifsumount - unmount UBIFS volume 218 219Usage: 220ubifsumount - unmount current volume 221 222For example: 223 224=> ubifsumount 225Unmounting UBIFS volume recovery! 226