Bob, I was afraid that you are thinking about boot times in the msec range. I have got ~1sec boot time with a 40MHz Atmel AT91 board just with using XIP for kernel + applications. In addition, I had to take out the HW reset for PCMCIA that was done with a ~0.5sec delay. The delay loop calibration would save another few 100msecs. BTW, which cpu are you planning to use?
It's quite a long time, but I can try to lookup the relevant celinux patches for you if you like. It may require a bit of tweaking, but shouldn't be difficult once you understand what the patch does. Regards, Erwin Am Donnerstag, den 14.02.2008, 07:14 -0700 schrieb Robert Warner: > Erwin, > > Now this is what i'd like to here. Less then 1 sec for startup time > would be absolutely perfect. This device is a hand held radio. The > people using these radios are used to typical analog radios, which at > power on are ready to go immediately. A less then one second boot and > initialization time would be perfect in this case. 30 seconds as > proposed by one of my colleagues at work seems to me to be far too long. > We are looking at operating the processor in the range of 20 to 40MHz. > > > Do you think the Patch from celinuw will work with the patched kernels > from uCLinux? Any risk of patches stepping on each other? > > tia - bob > > > Erwin Authried wrote: > > Hi Bob, > > what is the boot time that you require? With a few optimization tricks > > like making the kernel XIP from flash and using a patch from celinux to > > speed up the delay loop calibration you can easily get boot times of a > > few 100 msecs, depending on your cpu horsepower. > > > > Regards, > > Erwin > > > > Am Mittwoch, den 13.02.2008, 07:03 -0700 schrieb Robert Warner: > >> Hi > >> > >> I'm looking into the prospect of preloading all of the necessary tables > >> for applications and kernel such that when the device is turned on it > >> doesn't boot it just starts executing as if it had already gone through > >> all the booting and application(s) initialization(s). Has this aspect > >> of system operation with Linux or uCLinux ever been discussed? Search > >> the web i see instant-on with respect to BIOS (Linux-BIOS) and > >> SlapshTop's Linux (DeviceVM). > >> > >> In the automotive domain embedded systems don't 'boot'. They just start > >> executing at system start. All tasks and initializations are preloaded. > >> Some re-initialization of parts of start up are allowed, and at > >> various points of system operation. Other embedded systems domains also > >> have the concept of instant-on. > >> > >> Obviously, one way to do this is boot the system normally. Record the > >> current state of the system for all tables preloaded values, saving them > >> for preloading in the 'instant on release'. I need to think through > >> this more, but i think it;s clear in what i want to achieve. Just > >> curious if it's been done with uCLinux recently. > >> > >> tia - bob > >> _______________________________________________ > >> uClinux-dev mailing list > >> uClinux-dev@uclinux.org > >> http://mailman.uclinux.org/mailman/listinfo/uclinux-dev > >> This message was resent by uclinux-dev@uclinux.org > >> To unsubscribe see: > >> http://mailman.uclinux.org/mailman/options/uclinux-dev > _______________________________________________ > uClinux-dev mailing list > uClinux-dev@uclinux.org > http://mailman.uclinux.org/mailman/listinfo/uclinux-dev > This message was resent by uclinux-dev@uclinux.org > To unsubscribe see: > http://mailman.uclinux.org/mailman/options/uclinux-dev -- Dipl.-Ing. Erwin Authried Softwareentwicklung und Systemdesign _______________________________________________ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
