Re: [Embeddedxen-devel] HTC Desire configuration files

[Bornet R. <rom...@he...>]

Hi Hector,

Sorry for the late answer. I'll try to answer all your questions with as much details as possible.

________________________________
From: Hector Marco [hec...@gm...]
Sent: Friday, March 09, 2012 11:05 AM
To: Bornet Romain
Subject: Re: [Embeddedxen-devel] HTC Desire configuration files

>> Hi Romain,

>> Yes, I am interested in porting embeddedxen 2.0 to HTC Desire,
>> because I have a real HTC Desire device.

>> But I don't understand the followin:

>> 1) I need to compare dom0 kernel but what about XEN ?
>>    One thing is port XEN hypervisor, and other is port Dom0 , isn't it ?
>>    I have seen in hypervisor-4.0.2/arch/arm/mach-msm "board-bravo.c" but
>>    ¿ XEN is ready for HTC desire already ?

Yes you are right when saying that supporting a new platform involves 2 parts, dom0 and XEN.
We had at some time in the project a basic, experimental support for HTC Desire within Xen and it is the reason why you see a board-bravo.c file in the source tree. Unfortunately, we did not maintain further this port further when we switched over to HTC Desire HD. You should nevertheless be able to update the support for HTC Desire based on the existing board-bravo.c and on the board-spade.c used for the Desire HD.

>> 2) How can I do debugging ?
>>    If XEN is not ready for HTC_Desire How I could be do the debugging ?

Debugging is always difficult on such devices. When developing for HTC Desire or Desire HD, we had to "tinker" some direct access to the framebuffer to print out some debug messages but we never got a proper debugging infrastructure. It is often a problem when developing on consumer market devices.

>> I found the following:

>> Jtag (http://www.multi-com.pl/index.php/en_US,details,id_pr,7883,menu_mode,categories.html)
>>Module for HTC desire (http://www.multi-com.pl/index.php/en_US,details,id_pr,8149,menu_mode,categories.html)
>> But, I prefer don't open the device.

For our work on HTC Desire and Desire HD, we never worked with JTAG on-chip debuggers. It would have been nice and would have spare us much debugging time but, at that time, we did not find a suitable solution. Your JTAG probe and module sound interesting but I cannot say much on it since I never used them.

>> The other option that I found is to use a board.

This would be in fact the best option. Having a development board with open connectors, debug interfaces is always nice to work with.

>> The only two board that I found in that link
>> (http://www.bsquare.com/dragonboard.aspx) for chipset MSM were:
>> - MSM8655T-based Snapdragon
>> - Qualcomm Snapdragon MSM8660TM-based
>> Neither are for:
>> - HTC desire (Qualcomm QSD8250 Snapdragon)
>> - HTC Desire S (Qualcomm MSM8255 Snapdragon)
>> - HTC desire HD (Qualcomm MSM8255 Snapdragon)
>> - HTC sensation (Qualcomm MSM8260 Snapdragon)
>> - HTC Sentation XL. (Qualcomm MSM8255)

Right, there is no development board (at least publicly available) for the particular processors found on the HTC devices you mentioned. In our lab we recently bought a Dragonboard (http://www.bsquare.com/dragonboard.aspx) with an APQ8060 dual-core chip. We plan to port EmbeddedXen to this platform and to add some new features in the future but we still don't have any precise roadmap for this.

>> I tried the old configuration for HTC Desire whit the new relase embeddedxen2.0
>> but nothing is shown, just the first screen white with HTC green letters.
>> How Could I see the XEN output ?
As said above, we cannot see XEN output directly on HTC phones. With some basic framebuffer driver, we were able to print out some messages but nothing more. And this only in the early boot stage, before Android gets initialized and uses the framebuffer itself.

>> I compiled the original kernel (without XEN) for HTC desire activating ttyMSM2 but
>> not worked. ( http://code.google.com/p/android-serialport-api/wiki/Htc) and  I
>> think is not the best way because the UART need to be up and for HTC devices
>> is in Untested devices list.

We also tried to get a serial console on the devices but did not invest much time in this since we did not find how to correctly activate it on the Desire/Desire HD + it seems to require some special cable with level shifters, tinkered USB connector,...

>> So first I think I need a way to do a good debugging.
And I'm afraid that there is no way to do *good* debugging on these devices at a such low level. But I perhaps missed something at that time ?

>>In conclusion I am a bit lost :)
>> Thanks in advance.
>>Hector.

Regards,
     Romain

El 08/03/12 22:37, Bornet Romain escribió:

Hi Hector,



________________________________________
From: Hector Marco [hec...@gm...<mailto:hec...@gm...>]
Sent: Thursday, March 08, 2012 2:59 PM
To: emb...@li...<mailto:emb...@li...>
Subject: [Embeddedxen-devel] HTC Desire configuration files


Hi everyone,


Congratulations for the new release!
Currently I have an HTC Desire (not HD).
Do you have any configuration for XEN or Linux for HTC Desire ?


The latest release does not include out-of-the-box support for HTC Desire but we started the development on such devices before switching to Desire HD. We did not maintain the port on the the HTC Desire but it should be rather easy to have the latest EmbeddedXen and a dom0 running again on Desire.
Our paravitualized dom0 kernel was based on the 2.6.29 kernel for HTC Desire available from HTC.

If you are interested in porting EmbeddedXen 2.0 to Desire, the best way is to compare the 2.6.32-dom0 tree for Desire HD with the original kernel sources and apply similar changes to the 2.6.29 or 2.6.32 kernel sources for Desire. If you go this way, don't hesitate to ask for help on the list since we already know a bit on this device from our earlier experience.

A few links to useful reference kernel sources:
Desire HD original sources from HTC: http://dl4.htc.com/RomCode/Source_and_Binaries/ace_2.6.32_g5ed1769.tar.gz
Desire 2.6.29 original sources from HTC: http://dl4.htc.com/RomCode/Source_and_Binaries/bravo_54b7033a.tar.gz
Desire 2.6.32 original sources from HTC: http://dl4.htc.com/RomCode/Source_and_Binaries/bravo-2.6.32-gd96f2c0.tar.gz



Thanks in advance.
Hector.


Have fun with EmbeddedXen !
    Romain