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author | Allen Martin <amartin@nvidia.com> | 2012-12-19 13:02:36 -0800 |
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committer | Allen Martin <amartin@nvidia.com> | 2012-12-19 13:02:36 -0800 |
commit | a098cf41fdb2a6607c675f7fe4f3164617c9367e (patch) | |
tree | b37acb36f65909e6f74cc537d73efd883a1485a6 /doc | |
parent | b8a7c467960ffb4d5a5e1eef5f7783fb6f594542 (diff) | |
parent | 095728803eedfce850a2f85828f79500cb09979e (diff) | |
download | u-boot-imx-a098cf41fdb2a6607c675f7fe4f3164617c9367e.zip u-boot-imx-a098cf41fdb2a6607c675f7fe4f3164617c9367e.tar.gz u-boot-imx-a098cf41fdb2a6607c675f7fe4f3164617c9367e.tar.bz2 |
Merge remote-tracking branch 'u-boot/master' into u-boot-arm-merged
Conflicts:
README
arch/arm/cpu/armv7/exynos/clock.c
board/samsung/universal_c210/universal.c
drivers/misc/Makefile
drivers/power/power_fsl.c
include/configs/mx35pdk.h
include/configs/mx53loco.h
include/configs/seaboard.h
Diffstat (limited to 'doc')
-rw-r--r-- | doc/DocBook/Makefile | 2 | ||||
-rw-r--r-- | doc/README.gpt | 201 | ||||
-rw-r--r-- | doc/README.mpc85xx | 2 | ||||
-rw-r--r-- | doc/README.nand | 21 | ||||
-rw-r--r-- | doc/README.silent | 14 | ||||
-rw-r--r-- | doc/kwboot.1 | 2 |
6 files changed, 235 insertions, 7 deletions
diff --git a/doc/DocBook/Makefile b/doc/DocBook/Makefile index da88b32..521e8bc 100644 --- a/doc/DocBook/Makefile +++ b/doc/DocBook/Makefile @@ -8,7 +8,7 @@ include $(TOPDIR)/config.mk -DOCBOOKS := linker_lists.xml stdio.xml +DOCBOOKS := fs.xml linker_lists.xml stdio.xml ### # The build process is as follows (targets): diff --git a/doc/README.gpt b/doc/README.gpt new file mode 100644 index 0000000..a9c58b4 --- /dev/null +++ b/doc/README.gpt @@ -0,0 +1,201 @@ +# +# Copyright (C) 2012 Samsung Electronics +# +# Lukasz Majewski <l.majewski@samsung.com> +# +# +# See file CREDITS for list of people who contributed to this +# project. +# +# This program is free software; you can redistribute it and/or +# modify it under the terms of the GNU General Public License as +# published by the Free Software Foundation; either version 2 of +# the License, or (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 59 Temple Place, Suite 330, Boston, +# MA 02111-1307 USA + + +Glossary: +======== +- UUID -(Universally Unique Identifier) +- GUID - (Globally Unique ID) +- EFI - (Extensible Firmware Interface) +- UEFI - (Unified EFI) - EFI evolution +- GPT (GUID Partition Table) - it is the EFI standard part +- partitions - lists of available partitions (defined at u-boot): + ./include/configs/{target}.h + +Introduction: +============= +This document describes the GPT partition table format and usage of +the gpt command in u-boot. + + +UUID introduction: +==================== + +GPT for marking disks/partitions is using the UUID. It is supposed to be a +globally unique value. A UUID is a 16-byte (128-bit) number. The number of +theoretically possible UUIDs is therefore about 3 x 10^38. +More often UUID is displayed as 32 hexadecimal digits, in 5 groups, +separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters +(32 digits and 4 hyphens) + +For instance, GUID of Linux data partition: EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 + +Historically there are 5 methods to generate this number. The oldest one is +combining machine's MAC address and timer (epoch) value. + +Successive versions are using MD5 hash, random numbers and SHA-1 hash. All major +OSes and programming languages are providing libraries to compute UUID (e.g. +uuid command line tool). + +GPT brief explanation: +====================== + + Layout: + ------- + + -------------------------------------------------- + LBA 0 |Protective MBR | + ---------------------------------------------------------- + LBA 1 |Primary GPT Header | Primary + -------------------------------------------------- GPT + LBA 2 |Entry 1|Entry 2| Entry 3| Entry 4| + -------------------------------------------------- + LBA 3 |Entries 5 - 128 | + | | + | | + ---------------------------------------------------------- + LBA 34 |Partition 1 | + | | + ----------------------------------- + |Partition 2 | + | | + ----------------------------------- + |Partition n | + | | + ---------------------------------------------------------- + LBA -34 |Entry 1|Entry 2| Entry 3| Entry 4| Secondary + -------------------------------------------------- (bkp) + LBA -33 |Entries 5 - 128 | GPT + | | + | | + LBA -2 | | + -------------------------------------------------- + LBA -1 |Secondary GPT Header | + ---------------------------------------------------------- + + +For a legacy reasons, GPT's LBA 0 sector has a MBR structure. It is called +"protective MBR". +Its first partition entry ID has 0xEE value, and disk software, which is not +handling the GPT sees it as a storage device without free space. + +It is possible to define 128 linearly placed partition entries. + +"LBA -1" means the last addressable block (in the mmc subsystem: +"dev_desc->lba - 1") + +Primary/Secondary GPT header: +---------------------------- +Offset Size Description + +0 8 B Signature ("EFI PART", 45 46 49 20 50 41 52 54) +8 4 B Revision (For version 1.0, the value is 00 00 01 00) +12 4 B Header size (in bytes, usually 5C 00 00 00 meaning 92 bytes) +16 4 B CRC32 of header (0 to header size), with this field zeroed + during calculation +20 4 B Reserved (ZERO); +24 8 B Current LBA (location of this header copy) +32 8 B Backup LBA (location of the other header copy) +40 8 B First usable LBA for partitions (primary partition table last + LBA + 1) +48 8 B Last usable LBA (secondary partition table first LBA - 1) +56 16 B Disk GUID (also referred as UUID on UNIXes) +72 8 B Partition entries starting LBA (always 2 in primary copy) +80 4 B Number of partition entries +84 4 B Size of a partition entry (usually 128) +88 4 B CRC32 of partition array +92 * Reserved; must be ZERO (420 bytes for a 512-byte LBA) + +TOTAL: 512 B + + + +IMPORTANT: + +GPT headers and partition entries are protected by CRC32 (the POSIX CRC32). + +Primary GPT header and Secondary GPT header have swapped values of "Current LBA" +and "Backup LBA" and therefore different CRC32 check-sum. + +CRC32 for GPT headers (field "CRC of header") are calculated up till +"Header size" (92), NOT 512 bytes. + +CRC32 for partition entries (field "CRC32 of partition array") is calculated for +the whole array entry ( Number_of_partition_entries * +sizeof(partition_entry_size (usually 128))) + +Observe, how Secondary GPT is placed in the memory. It is NOT a mirror reflect +of the Primary. + + + Partition Entry Format: + ---------------------- + Offset Size Description + + 0 16 B Partition type GUID + 16 16 B Unique partition GUID + 32 8 B First LBA (Little Endian) + 40 8 B Last LBA (inclusive) + 48 8 B Attribute flags [+] + 56 72 B Partition name (text) + + Attribute flags: + Bit 0 - System partition + Bit 60 - Read-only + Bit 62 - Hidden + Bit 63 - Not mount + + +Creating GPT partitions in U-Boot: +============== + +To restore GUID partition table one needs to: +1. Define partition layout in the environment. + Format of partitions layout: + "partitions=uuid_disk=...;name=u-boot,size=60MiB,uuid=...; + name=kernel,size=60MiB,uuid=...;" + or + "partitions=uuid_disk=${uuid_gpt_disk};name=${uboot_name}, + size=${uboot_size},uuid=${uboot_uuid};" + + Fields 'name', 'size' and 'uuid' are mandatory for every partition. + The field 'start' is optional. + +2. Define 'CONFIG_EFI_PARTITION' and 'CONFIG_CMD_GPT' + +2. From u-boot prompt type: + gpt write mmc 0 $partitions + + +Useful info: +============ + +Two programs, namely: 'fdisk' and 'parted' are recommended to work with GPT +recovery. Parted is able to handle GUID partitions. Unfortunately the 'fdisk' +hasn't got such ability. +Please, pay attention at -l switch for parted. + +"uuid" program is recommended to generate UUID string. Moreover it can decode +(-d switch) passed in UUID string. It can be used to generate partitions UUID +passed to u-boot environment variables. diff --git a/doc/README.mpc85xx b/doc/README.mpc85xx index 5a4b591..f9b023f 100644 --- a/doc/README.mpc85xx +++ b/doc/README.mpc85xx @@ -26,7 +26,7 @@ Major Config Switches during various boot Modes ---------------------------------------------- NOR boot - !defined(CONFIG_SYS_RAMBOOT) + !defined(CONFIG_SYS_RAMBOOT) && !defined(CONFIG_SPL) NOR boot Secure !defined(CONFIG_SYS_RAMBOOT) && defined(CONFIG_SECURE_BOOT) RAMBOOT(SD, SPI & NAND boot) diff --git a/doc/README.nand b/doc/README.nand index c130189..a1a511c 100644 --- a/doc/README.nand +++ b/doc/README.nand @@ -108,6 +108,9 @@ Configuration Options: CONFIG_CMD_NAND Enables NAND support and commmands. + CONFIG_CMD_NAND_TORTURE + Enables the torture command (see description of this command below). + CONFIG_MTD_NAND_ECC_JFFS2 Define this if you want the Error Correction Code information in the out-of-band data to be formatted to match the JFFS2 file system. @@ -213,6 +216,24 @@ Miscellaneous and testing commands: DANGEROUS!!! Factory set bad blocks will be lost. Use only to remove artificial bad blocks created with the "markbad" command. + "torture offset" + Torture block to determine if it is still reliable. + Enabled by the CONFIG_CMD_NAND_TORTURE configuration option. + This command returns 0 if the block is still reliable, else 1. + If the block is detected as unreliable, it is up to the user to decide to + mark this block as bad. + The analyzed block is put through 3 erase / write cycles (or less if the block + is detected as unreliable earlier). + This command can be used in scripts, e.g. together with the markbad command to + automate retries and handling of possibly newly detected bad blocks if the + nand write command fails. + It can also be used manually by users having seen some NAND errors in logs to + search the root cause of these errors. + The underlying nand_torture() function is also useful for code willing to + automate actions following a nand->write() error. This would e.g. be required + in order to program or update safely firmware to NAND, especially for the UBI + part of such firmware. + NAND locking command (for chips with active LOCKPRE pin) diff --git a/doc/README.silent b/doc/README.silent index a26e3df..70202ce 100644 --- a/doc/README.silent +++ b/doc/README.silent @@ -1,9 +1,15 @@ The config option CONFIG_SILENT_CONSOLE can be used to quiet messages on the console. If the option has been enabled, the output can be -silenced by setting the environment variable "silent". The variable -is latched into the global data at an early stage in the boot process -so deleting it with "setenv" will not take effect until the system is -restarted. +silenced by setting the environment variable "silent". + +- CONFIG_SILENT_CONSOLE_UPDATE_ON_SET + When the "silent" variable is changed with env set, the change + will take effect immediately. + +- CONFIG_SILENT_CONSOLE_UPDATE_ON_RELOC + Some environments are not available until relocation (e.g. NAND) + so this will make the value in the flash env take effect at + relocation. The following actions are taken if "silent" is set at boot time: diff --git a/doc/kwboot.1 b/doc/kwboot.1 index ed08398..25fe69a 100644 --- a/doc/kwboot.1 +++ b/doc/kwboot.1 @@ -79,6 +79,6 @@ Adjust the baud rate on \fITTY\fP. Default rate is 115200. Daniel Stodden <daniel.stodden@gmail.com> .br -Luka Perkov <uboot@lukaperkov.net> +Luka Perkov <luka@openwrt.org> .br David Purdy <david.c.purdy@gmail.com> |