2008-06-06 11:55:29     Booting two separate applications from Flash

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2008-06-06 11:55:29     Booting two separate applications from Flash

Appalayagari Sreedhar (INDIA)

Message: 56821   




I am having two applications in my flash chip.


u-boot and


1. Normal application


2. Standby application.


Normal application i am booting using the bootcmd "bootm" from u-boot.


whenever there is a inactivity for sometime or some specific event. i want to boot the standby application.


I am finding it difficult to boot the standby application when an external event occurs/inactivity of my system.


is there any possibility to start booting the second application (standby) from Normal application using such "boot" commands from Normal application.


or is there any other ways or methods how to implement this scenario in uClinux. I am aware of this implementation in VDSP but i am finding it little difficult to implement the same in uClinux.


your suggestions are most welcome.


thanks in advance.






2008-06-06 15:50:25     Re: Booting two separate applications from Flash

Mike Frysinger (UNITED STATES)

Message: 56828   


"booting" means you load and execute an application and never return


u-boot is not an operating system ... it doesnt monitor things


it is up to you to implement such policy decisions in our own code




2008-06-06 16:26:29     Re: Booting two separate applications from Flash

Graham Davies (UNITED STATES)

Message: 56832   




Maybe you can look at it this way: In your Flash chip you have 1) u-boot, which is a boot loader, and 2) uClinux, which is an operating system bundled with any number of applications.  The job of u-boot is to start uClinux from cold.  Once uClinux is up, you can do pretty much anything you want.  Forget u-boot, at that time.  The rc script in your <board>/<vendor> directory defines what applications uClinux runs when it starts.  Once you have your own applications started, you can start others, shut them down and do all kinds of things which I'm sure will cover your needs.  Just let go of the idea of using u-boot to boot alternate "applications".








2008-06-11 14:05:37     Re: Booting two separate applications from Flash


Message: 57021   




It is possible (for you to do), to have U-Boot read the Software Reset Register (SWRST) - if the watchdog kicks off, then it does action/image B. If it has not - action/image A.


But this is not something that is done/supported/would be accepted - since it breaks other existing use cases (where everything is done in the kernel).