[yocto] meta-cedartrail - serial console

[jfabernathy]

On 06/01/2012 01:01 PM, Darren Hart wrote:
>
> On 06/01/2012 08:45 AM, jfabernathy wrote:
>> On 05/31/2012 03:41 PM, Darren Hart wrote:
>>> On 05/31/2012 11:54 AM, jfabernathy wrote:
>>>> On 05/31/2012 02:13 PM, Darren Hart wrote:
>>>>> On 05/31/2012 09:11 AM, jfabernathy wrote:
>>>>>> Using a DN2800MT (Marshalltown) Intel board, I'm testing the
>>>>>> meta-cedartrail using edison branch and noticed an issues with the
>>>>>> serial console.
>>>>>>
>>>>>> The cedartrail.conf in the machine directory has the following statements:
>>>>>>
>>>>>> SYSLINUX_OPTS = "serial 0 115200"
>>>>>> SERIAL_CONSOLE = "115200 ttyS0"
>>>>>> APPEND += "console=ttyS0,115200 console=tty0"
>>>>>>
>>>>>> However, when the image booted, I had no serial console on ttyS0.  I
>>>>>> checked /etc/inittab and noticed that the following line existed:
>>>>>>
>>>>>> S:2345:respawn:/sbin/getty 115200 ttyS3
>>>>>>
>>>>>> I changed the ttyS3 to ttyS0 and then I have a serial console on the
>>>>>> next reboot.  So it appears the override in the .conf file is not
>>>>>> working.  Also I only have the console from getty, and not the kernel
>>>>>> logging console.
>>>>>>
>>>>>> Anyone have a solution??
>>>>>>
>>>>>> If this is considered a bug I can put it on bugzilla.
>>>>> Lets make sure your environment is what we expect. Please provide the
>>>>> output of:
>>>>>
>>>>> $ bitbake core-image-minimal -e | grep SERIAL_CONSOLE=
>>>>>
>>>>> If it is not "115200 ttyS0" then it is getting overwritten somewhere
>>>>> either in your config, or possibly by an inappropriate selection of an
>>>>> assignment operator (=, ?=, etc.) in edison.
>>>> okay now I'm confused.  while the cedartrail.conf file has the following:
>>>> SYSLINUX_OPTS = "serial 3 115200"
>>>> SERIAL_CONSOLE = "115200 ttyS3"
>>>> APPEND += "console=ttyS3,115200 console=tty3"
>>>>
>>>>
>>>> The output of the bitbake command you suggested above gives:
>>>> jim at ubuntu-x64:~/poky/build$ bitbake core-image-minimal -e | grep
>>>> SERIAL_CONSOLE=
>>>>
>>>> # SERIAL_CONSOLE=115200 ttyS0
>>>> SERIAL_CONSOLE="115200 ttyS0"
>>>> jim at ubuntu-x64:~/poky/build$
>>>>
>>>> So is the bitbake command showing the results before the cedartrail.conf
>>>> options take affect??
>>> variable assignments can be tricky, and are not the easiest things to
>>> track down. I suggest looking through your configured layers and looking
>>> for all the SERIAL_CONSOLE assignments using ttyS3 and ttyS0 and see if
>>> you can determine what is overriding your cedartrail.conf setting.
>>>
>> What I found out is the only variable that matters for login console in
>> my situation is SERIAL_CONSOLE because I have to use grub and the boot
>> from hard drive method because my image can't be put on a USB Flash for
>> some reason.  So I manually have to edit the grub.cfg file as documented
>> on the wiki "How Do I" section of putting Yocto on a hard drive.  Adding
>> console=ttyS0,115200 on the linux statement takes care of the boot console.
> I believe this is a manual process currently. Please open an enhancement
> in bugzilla for your specific situation and I'll incporporate into the
> larger boot process and image revamp we're doing for 1.3.
>
I'll make the entry.
>> So the question is has there been any thought about automating the
>> choice of boot loader and the parameters that are needed or optional?
>> In the case of meta-cedartrail, the cedartrail.conf assumes syslinux is
>> the boot loader. When I could use a USB Flash key, creating a boot
>> device was a trivial dd statement.  Because I have to use a hard drive
>> now, I have to do a number of manual steps.  Or is there a way to create
>> a boot-able hard drive with syslinux so the cedartrail.conf parameters
>> are all that is needed to adjust?
> This is all good feedback to consider as we work through making more
> universally bootable images. This is becoming a hot topic as people are
> using Yocto in more and more situations and as things like EFI become
> more commonplace.
>
> There is no reason you can't just dd (have a look at
> scripts/contrib/ddimage) the image to a hard disk instead of a usb
> stick. You may need a USB to SATA adapter for your host (this is what I
> use). If you have a USB port, you could just use the install option.
This script does not eliminate the boot error I get with syslinux on USB 
flash keys.  I noticed the script is not in edison but is in denzil, so 
I got it there and tried to run it against an image created with 
edison.  I still get the same boot error I get with dd, which is 
understandable since that's what the script uses.  Not sure if this is a 
size issue because my image is over a 1GB.  I'm guessing this this will 
still fail on a hard drive with the dd'ing of the .hddimg, but I'll test 
it anyway.
> The integration between the boot loader options is something that needs
> work. At some point I hope to replace GRUB with syslinux in all possible
> situations in order simplify the option handling and present a
> consistent boot interface between live images, iso limages, and disk images.
>