mmc.1

.TH man 1 "16 November 2015" "0.1" "mmc-utils man page"
.SH
NAME
mmc-utils \- Configure MMC storage devices from userspace.
.SH
SYNOPSIS
mmc [<command> [<args>]] [--help]
.PP
mmc [<command>] --help
.SH
DESCRIPTION
mmc-utils is a tool for configuring MMC storage devices from userspace.
.SH
COMMANDS AND OPTIONS
.TP
.BR "help | \-\-help | -h | " "(no arguments)"
Shows the abbreviated help menu in the terminal.
.TP
.BR "extcsd read <device>"
Print extcsd data from <device>.
.TP
.BR "writeprotect get <device>"
Determine the eMMC writeprotect status of <device>.
.TP
.BR "writeprotect set <device>"
Set the eMMC writeprotect status of <device>.
This sets the eMMC to be write-protected until next boot.
.TP
.BR "disable 512B emulation <device>"
Set the eMMC data sector size to 4KB by disabling emulation on
<device>.
.TP
.BR "gp create <-y|-n> <length KiB> <partition> <enh_attr> <ext_attr> <device>"
create general purpose partition for the <device>.
Dry-run only unless -y is passed.
To set enhanced attribute to general partition being created set <enh_attr> to 1 else set it to 0.
To set extended attribute to general partition set <ext_attr> to 1,2 else set it to 0.
NOTE!  This is a one-time programmable (unreversible) change.
.TP
.BR "enh_area set <-y|-n> <start KiB> <length KiB> <device>"
Enable the enhanced user area for the <device>.
Dry-run only unless -y is passed.
NOTE!  This is a one-time programmable (unreversible) change.
.TP
.BR "write_reliability set <-y|-n> <partition> <device>"
Enable write reliability per partition for the <device>.
Dry-run only unless -y is passed.
NOTE!  This is a one-time programmable (unreversible) change.
.TP
.BR "status get <device>"
Print the response to STATUS_SEND (CMD13).
.TP
.BR "bootpart enable <boot_partition> <send_ack> <device>"
Enable the boot partition for the <device>.
Disable the boot partition for the <device> with <boot_partition> set to 0.
To receive acknowledgment of boot from the card set <send_ack>
to 1, else set it to 0.
.TP
.BR "bootbus set <boot_mode> <reset_boot_bus_conditions> <boot_bus_width> <device>"
Set Boot Bus Conditions.
<boot_mode> must be "single_backward|single_hs|dual"
<reset_boot_bus_conditions> must be "x1|retain"
<boot_bus_width> must be "x1|x4|x8"
.TP
.BR "bkops enable <device>"
Enable the eMMC BKOPS feature on <device>.
NOTE!  This is a one-time programmable (unreversible) change.
.TP
.BR "hwreset enable <device>"
Permanently enable the eMMC H/W Reset feature on <device>.
NOTE!  This is a one-time programmable (unreversible) change.
.TP
.BR "hwreset disable <device>"
Permanently disable the eMMC H/W Reset feature on <device>.
NOTE!  This is a one-time programmable (unreversible) change.
.TP
.BR "sanitize <device>"
Send Sanitize command to the <device>.
This will delete the unmapped memory region of the device.
.TP
.BR "rpmb write-key <rpmb device> <key file>"
Program authentication key which is 32 bytes length and stored
in the specified file. Also you can specify '-' instead of
key file path to read the key from stdin.
NOTE!  This is a one-time programmable (unreversible) change.
.TP
.BR "rpmb read-counter <rpmb device>"
Counter value for the <rpmb device> will be read to stdout.
.TP
.BR "rpmb read-block <rpmb device> <address> <blocks count> <output file> [key file]"
Blocks of 256 bytes will be read from <rpmb device> to output
file or stdout if '-' is specified. If key is specified - read
data will be verified. Instead of regular path you can specify
'-' to read key from stdin.
.TP
.BR "rpmb write-block <rpmb device> <address> <256 byte data file> <key file>"
Block of 256 bytes will be written from data file to
<rpmb device>. Also you can specify '-' instead of key
file path or data file to read the data from stdin.
.TP
.BR "cache enable <device>"
Enable the eMMC cache feature on <device>.
NOTE! The cache is an optional feature on devices >= eMMC4.5.
.TP
.BR "cache disable <device>"
Disable the eMMC cache feature on <device>.
NOTE! The cache is an optional feature on devices >= eMMC4.5.
.TP
.BR "<cmd> --help"
Show detailed help for a command or subset of commands.

.SH
EXAMPLES
.TP
Program authentication key from stdin:
echo -n AAAABBBBCCCCDDDDEEEEFFFFGGGGHHHH | mmc rpmb write-key /dev/mmcblk0rpmb -
.TP
Write a block of 256 bytes of data to an rpmb device:
$ (awk 'BEGIN {while (c++<256) printf "a"}' | echo -n AAAABBBBCCCCDDDDEEEEFFFFGGGGHHHH) | mmc rpmb write-block /dev/mmcblk0rpmb 0x02 - -
.TP
Read a block of 256 bytes of data from an rpmb device to stdout:
  $ echo -n AAAABBBBCCCCDDDDEEEEFFFFGGGGHHHH | mmc rpmb read-block /dev/mmcblk0rpmb 0x02 2 /tmp/block -
.TP
Read 2 blocks of 256 bytes from rpmb device to /tmp/block without verification:
$ mmc rpmb read-block /dev/mmcblk0rpmb 0x02 2 /tmp/block