i.MX ProcessorsのトピックRe: Using UART port on QSB

Using UART port on QSB

VincentChou1z — Tue, 24 Apr 2012 14:12:11 GMT

Hi! Friends,

Is there any step we could follow to use the RJ45 to connect to a module which we could control the module through UART? Should we change the console parameter in the uboot environment so it will not interfere with our UART commands?

Vincent

Re: Using UART port on QSB

Serge1z — Tue, 24 Apr 2012 14:48:05 GMT

you can try something like that:

setenv bootargs_mmc 'setenv bootargs ip=192.168.10.24 root=/dev/mmcblk0p1 rootwait rw'

192.168.10.24 is ip-addr of your QSB

also you are to install sshd and put it's name in autostart string... as far as I remember it is in /etc/rc.d/rc.conf

cfg_services="mount-proc-sys udev hostname depmod modules filesystems inetd sshd "

cfg_services_r=" sshd inetd filesystems modules depmod hostname udev mount-proc-sys"

Re: Using UART port on QSB

VincentChou1z — Fri, 27 Apr 2012 02:04:16 GMT

Thanks! When you set ip=192.168.10.24 (assuming my ip is 192.168.10.24), is it going to specify the IP address only? I remember there is an env parameter "console=ttymxc0,115200' in bootargs_base. If we still keep that, we are going to see a lot of debug message output through the console. Am I right?

Re: Using UART port on QSB

Serge1z — Fri, 27 Apr 2012 09:59:29 GMT

yes, you are right

but if this env parameter "console=ttymxc0,115200' is removed, as far as I remember some debug information from u-boot will be sent anyway

Re: Using UART port on QSB

Serge1z — Sat, 28 Apr 2012 12:02:58 GMT

My QSB sends to serial the following information:

U-Boot 2009.08 (Sep 24 2011 - 22:18:53)

CPU:   Freescale i.MX53 family 2.1V at 800 MHz
mx53 pll1: 800MHz
mx53 pll2: 400MHz
mx53 pll3: 432MHz
mx53 pll4: 455MHz
ipg clock     : 66666666Hz
ipg per clock : 33333333Hz
uart clock    : 66666666Hz
cspi clock    : 108000000Hz
ahb clock     : 133333333Hz
axi_a clock   : 400000000Hz
axi_b clock   : 200000000Hz
emi_slow clock: 133333333Hz
ddr clock     : 400000000Hz
esdhc1 clock : 80000000Hz
esdhc2 clock : 80000000Hz
esdhc3 clock : 80000000Hz
esdhc4 clock : 80000000Hz
nfc clock     : 26666666Hz
Board: MX53-LOCO 1.0 Rev. B
Boot Reason: [WDOG]
Boot Device: SD
I2C:   ready
DRAM:   1 GB
MMC:   FSL_ESDHC: 0,FSL_ESDHC: 1
In:    serial
Out:   serial
Err:   serial
Serial reinitilized!
Net:   got MAC address from IIM: 00:04:9f:01:f5:76
FEC0 [PRIME]
Hit any key to stop autoboot: 0
mmc0 is current device

MMC read: dev # 0, block # 2048, count 6144 ... 6144 blocks read: OK
## Booting kernel from Legacy Image at 70800000 ...
   Image Name:   Linux-2.6.35.3-1129-g691c08a
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    3008108 Bytes = 2.9 MB
   Load Address: 70008000
   Entry Point: 70008000
   Verifying Checksum ... OK
   Loading Kernel Image ... OK
OK

Starting kernel ...

Linux version 2.6.35.3-1129-g691c08a (root@serge-desktop) (gcc version 4.4.4 (4.4.4_09.06.2010) ) #1 PREEMPT Fri Apr 6 21:01:20 MSK 2012
CPU: ARMv7 Processor [412fc085] revision 5 (ARMv7), cr=10c53c7f
CPU: VIPT nonaliasing data cache, VIPT nonaliasing instruction cache
Machine: Freescale MX53 LOCO Board
Memory policy: ECC disabled, Data cache writeback
Built 1 zonelists in Zone order, mobility grouping on. Total pages: 250880
Kernel command line: ip=192.168.10.24 root=/dev/mmcblk0p1 rootwait rw
PID hash table entries: 4096 (order: 2, 16384 bytes)
Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
Memory: 480MB 512MB = 992MB total
Memory: 998220k/998220k available, 17588k reserved, 0K highmem
Virtual kernel memory layout:
    vector : 0xffff0000 - 0xffff1000   (   4 kB)
    fixmap : 0xfff00000 - 0xfffe0000   ( 896 kB)
    DMA     : 0xf9e00000 - 0xffe00000   ( 96 MB)
    vmalloc : 0xe0800000 - 0xf4000000   ( 312 MB)
    lowmem : 0x80000000 - 0xe0000000   (1536 MB)
    pkmap   : 0x7fe00000 - 0x80000000   (   2 MB)
    modules : 0x7f000000 - 0x7fe00000   ( 14 MB)
      .init : 0x80008000 - 0x80033000   ( 172 kB)
      .text : 0x80033000 - 0x807fa000   (7964 kB)
      .data : 0x80818000 - 0x80870120   ( 353 kB)
SLUB: Genslabs=11, HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
Hierarchical RCU implementation.
        RCU-based detection of stalled CPUs is disabled.
        Verbose stalled-CPUs detection is disabled.
NR_IRQS:368
MXC GPIO hardware
MXC IRQ initialized
MXC_Early serial console at MMIO 0x53fbc000 (options '115200')
bootconsole [ttymxc0] enabled
Console: colour dummy device 80x30
console [tty0] enabled, bootconsole disabled

I don't really know if it sends to each serial port or not (I don't have a special module for QSB).

If you find out how it works in detail, write here please.

Thanks for collaboration.

Re: Using UART port on QSB

VincentChou1z — Tue, 08 May 2012 08:50:30 GMT

Hi! Serg,

I came across some strange ssh error and it shows

=============

The authenticity of host '10.1.1.112 (10.1.1.112)' can't be established.
RSA key fingerprint is 24:72:08:c9:45:7e:46:8b:cc:11:81:ec:90:65:55:64.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '10.1.1.112' (RSA) to the list of known hosts.
root@10.1.1.112's password:
Permission denied, please try again.
=============

However, I have already started dropbear when booted. Is there anything I should set in order to login through SSH like this way?

I appreciate your help!

Vincent

Re: Using UART port on QSB

VincentChou1z — Thu, 10 May 2012 03:23:07 GMT

Hi! Serg,

I discovered that I need to create another user to use ssh on my PC to login to the target board. Now the problem becomes how I could enable "sudo" in my target machine with the MIN profile configuration. Could you provide me some idea? Thanks!

Vincent

Re: Using UART port on QSB

Serge1z — Thu, 10 May 2012 06:55:52 GMT

Hi Vincent,

Actually you don't need to create another user to login on your PC. That can be needed only for security.

I guess it's better to allow of empty passwords.

/etc/ssh/sshd_config

PermitEmptyPasswords yes

Serge

Re: Using UART port on QSB

VincentChou1z — Mon, 14 May 2012 09:11:50 GMT

Hi! Serge,

I created another account to login and then use "su root" to change user and it works. Thanks anyway!

Vincent