Re: [beagleboard] PREBOOT delay. Is it possible to reduce it?
> On Nov 17, 2015, at 14:18 , Robert Nelsonwrote: > > On Tue, Nov 17, 2015 at 4:15 PM, Robert Nelson > wrote: migration to driver model http://git.denx.de/?p=u-boot.git;a=tree;f=doc/driver-model;hb=HEAD >>> >>> Robert, do you mean that U-Boot is migrating to driver model during that >>> delay? Or the delay is the result of U-boot having updated to the new >>> driver model? >>> >>> If the latter, what's it doing during those two seconds? Is there any way >>> to speed that up? Eventually, I'd like to have a very fast-booting BBB. >> >> For me, it was around the initial driver model merge that we got that >> slight delay. >> >> Of course, it might also be newer ddr timing init.. >> >> The slow down didn't really bug me so i never looked too deeply in it.. >> >> But if you guys want speed, switch to u-boot's falcon mode: >> >> MLO -> kernel >> >> vs: >> >> MLO -> u-boot.img -> kernel >> >> it might not be 100% evident, but you'll need to hardcode a lot of >> stuff in MLO that u-boot.img currently reads from uEnv.txt > > For other speed up's, look into the am335x_evm board/mux files, you'll > notice it relies on reading an eeprom over i2c.. A lot of that can be > factored out if you know exactly what board you have. (i2c can be > slow)... Awesome, thanks. Yeah, in my application, it's an appliance that will have very well-understood configurations. -- Rick Mann rm...@latencyzero.com -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] PREBOOT delay. Is it possible to reduce it?
> On Nov 17, 2015, at 11:57 , Robert Nelsonwrote: > > On Tue, Nov 17, 2015 at 1:37 PM, wrote: >> >> I have tried run defferent images from SD: >> >> 1.Debian 2015-07-28 console with u-boot v2015.01 writed to unallocated space >> in front of first partition - 2 second delay remains >> 2.Jessie Snapshot console with u-boot v2015.10 writed to unallocated space >> in front of first partition - 2 second delay remains >> 3. Angstrom v2012.12 (kernel 3.8.13) with u-boot 2013.04-dirty writed to >> FAT32-MLO BOOT partition - start immediately after plug in power supply >> >> >> So, I assumed that the problem is in the method of placing the loader. But >> if replace u-boot v2015.01 with u-boot v2013.04, then delay disappears. The >> new version has something that leads to a pause. What could it be? > > migration to driver model > > http://git.denx.de/?p=u-boot.git;a=tree;f=doc/driver-model;hb=HEAD Robert, do you mean that U-Boot is migrating to driver model during that delay? Or the delay is the result of U-boot having updated to the new driver model? If the latter, what's it doing during those two seconds? Is there any way to speed that up? Eventually, I'd like to have a very fast-booting BBB. Thanks, -- Rick Mann rm...@latencyzero.com -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] PREBOOT delay. Is it possible to reduce it?
On Tue, Nov 17, 2015 at 4:15 PM, Robert Nelsonwrote: >>> migration to driver model >>> >>> http://git.denx.de/?p=u-boot.git;a=tree;f=doc/driver-model;hb=HEAD >> >> Robert, do you mean that U-Boot is migrating to driver model during that >> delay? Or the delay is the result of U-boot having updated to the new driver >> model? >> >> If the latter, what's it doing during those two seconds? Is there any way to >> speed that up? Eventually, I'd like to have a very fast-booting BBB. > > For me, it was around the initial driver model merge that we got that > slight delay. > > Of course, it might also be newer ddr timing init.. > > The slow down didn't really bug me so i never looked too deeply in it.. > > But if you guys want speed, switch to u-boot's falcon mode: > > MLO -> kernel > > vs: > > MLO -> u-boot.img -> kernel > > it might not be 100% evident, but you'll need to hardcode a lot of > stuff in MLO that u-boot.img currently reads from uEnv.txt For other speed up's, look into the am335x_evm board/mux files, you'll notice it relies on reading an eeprom over i2c.. A lot of that can be factored out if you know exactly what board you have. (i2c can be slow)... Regards, -- Robert Nelson https://rcn-ee.com/ -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] PREBOOT delay. Is it possible to reduce it?
>> migration to driver model >> >> http://git.denx.de/?p=u-boot.git;a=tree;f=doc/driver-model;hb=HEAD > > Robert, do you mean that U-Boot is migrating to driver model during that > delay? Or the delay is the result of U-boot having updated to the new driver > model? > > If the latter, what's it doing during those two seconds? Is there any way to > speed that up? Eventually, I'd like to have a very fast-booting BBB. For me, it was around the initial driver model merge that we got that slight delay. Of course, it might also be newer ddr timing init.. The slow down didn't really bug me so i never looked too deeply in it.. But if you guys want speed, switch to u-boot's falcon mode: MLO -> kernel vs: MLO -> u-boot.img -> kernel it might not be 100% evident, but you'll need to hardcode a lot of stuff in MLO that u-boot.img currently reads from uEnv.txt Regards, -- Robert Nelson https://rcn-ee.com/ -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.