mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-14 17:07:38 +00:00
45 lines
1.3 KiB
ReStructuredText
45 lines
1.3 KiB
ReStructuredText
|
.. SPDX-License-Identifier: GPL-2.0-or-later:
|
||
|
|
|
||
|
|
read and write commands
|
||
|
|
=======================
|
||
|
|
|
||
|
|
Synopsis
|
||
|
|
--------
|
||
|
|
|
||
|
|
::
|
||
|
|
|
||
|
|
read <interface> <dev[:part|#partname]> <addr> <blk#> <cnt>
|
||
|
|
write <interface> <dev[:part|#partname]> <addr> <blk#> <cnt>
|
||
|
|
|
||
|
|
The read and write commands can be used for raw access to data in
|
||
|
|
block devices (or partitions therein), i.e. without going through a
|
||
|
|
file system.
|
||
|
|
|
||
|
|
read
|
||
|
|
----
|
||
|
|
|
||
|
|
The block device is specified using the <interface> (e.g. "mmc") and
|
||
|
|
<dev> parameters. If the block device has a partition table, one can
|
||
|
|
optionally specify a partition number (using the :part syntax) or
|
||
|
|
partition name (using the #partname syntax). The command then reads
|
||
|
|
the <cnt> blocks of data starting at block number <blk#> of the given
|
||
|
|
device/partition to the memory address <addr>.
|
||
|
|
|
||
|
|
write
|
||
|
|
-----
|
||
|
|
|
||
|
|
The write command is completely equivalent to the read command, except
|
||
|
|
of course that the transfer direction is reversed.
|
||
|
|
|
||
|
|
Examples
|
||
|
|
--------
|
||
|
|
|
||
|
|
# Read 2 MiB from partition 3 of mmc device 2 to $loadaddr
|
||
|
|
read mmc 2.3 $loadaddr 0 0x1000
|
||
|
|
|
||
|
|
# Read 16 MiB from the partition named 'kernel' of mmc device 1 to $loadaddr
|
||
|
|
read mmc 1#kernel $loadaddr 0 0x8000
|
||
|
|
|
||
|
|
# Write to the third sector of the partition named 'bootdata' of mmc device 0
|
||
|
|
write mmc 0#bootdata $loadaddr 2 1
|