Dave Embedded Systems SBC AXEL, Руководство пользователя

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S B C X U s e r ' s G u i d e v . 1 . 0 . 1
7.3.3.7 NFS Server
One of the most important components of a Linux system is the root file
system. A good development root file system provides the developer with
all the useful tools that can help developers on their work. Such a root file
system can become very big in size, so it's hard to store it in flash
memory. User could split the file system in different parts, mounting them
from different media (flash, network, usb...). But the most convenient
thing is to mount the whole root file system from the network, allowing the
host system and the target to share the same files. In this way,
developers can quickly modify the root file system, even “on the fly”
(meaning that the file system can be modified while the system is
running). The most common way to setup a system like the one
described is through NFS (Network File System). As for TFTP, installation
and configuration depends on the host Linux distribution.
The default DVDK NFS installation is configured for sharing
/home
directory and all the subdirectories.
7.3.3.8 Pre-built toolchain
To start developing software for the AXEL platform, users need a proper
toolchain, which can be pre-built or built-from-scratch. Building a
toolchain from scratch is not a trivial task (though using a recent build
system is easier than in the past), so the recommended approach
consists in using a pre-built toolchain.
XELK provides the Poky toolchain built with the Yocto 1.5 version (
GCC
version is 4.8.1 ).
7.3.3.9 Pre-built root file system
Linux needs a root file system: a root file system must contain everything
needed to support the Linux system (applications, settings, data, ..). The
root file system is the file system that is contained on the same partition
on which the root directory is located. The Linux kernel, at the end of its
startup stage, mounts the root file system on the configured root device
and finally launches the /sbin/init, the first user space process and
"father" of all the other processes. An example of root file system is
shown below:
December, 2019
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