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
Please also note that the imx6q-cpufreq driver ( http://lxr.free-
electrons.com/source/drivers/cpufreq/imx6q-cpufreq.c? v=3.10 ) works on
a per-SOC policy (and not on a per-core one), so the cpufreq governor
changes the clock speed for all the ARM cores simultaneously.
8.7 How can I limit the number of active CPU cores?
A: To evaluate the performances of the system with reduced number of
CPU cores, the user can pass the maxcpus parameter to the kernel, by
setting the command line arguments in u-boot.
For example, to set the number of active cores to 2, add the maxcpus
parameter to the addmisc environment variable:
setenv addmisc 'setenv bootargs ${bootargs} maxcpus=2'
And add the addmisc variable to the boot macro:
setenv net_nfs 'run loadk loadfdt nfsargs addip addcons addmisc;
bootm ${buf} ${dtb_addr}'
For further details, please refer to the Documentation/kernel-
parameters.txt file of the kernel source tree provided with the XELK.
8.8 Q: How can I modify the IP address of the board?
A: The network configuration is managed by a mix of init scripts and
configuration files. In particular, the
/etc/network/interfaces
provides the interface settings used by the
ifup
and
ifdown
scripts,
which are in turn activated by the
/etc/init.d/networking
init
script. A basic strategy for IP address management is:
●
set a factory default
● allow customers to change it by modifying the
/etc/network/interfaces
file.
An example is the following, that sets a static ip address and reads the
MAC address from the kernel command line:
# /etc/network/interfaces -- configuration file for ifup(8),
ifdown(8)
# The loopback interface
auto lo
iface lo inet loopback
# Wired or wireless interfaces
auto eth0
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