[U-Boot-Users] DaVinci DM644x timer problem (divided by 16)

Dirk Behme dirk.behme at googlemail.com
Fri Mar 21 09:54:25 CET 2008


Pieter Voorthuijsen wrote:
> Hi Dirk,
> 
> If I understand correctly: When the timer wraps around, flash writes or
> other long lasting actions get timed-out. 

Yes. I never observed it myself. The inital report is

http://article.gmane.org/gmane.comp.boot-loaders.u-boot/32563/match=patch+fix+timer+overflow+davinci

but the patch was rejected by Wolfgang.

I then tried to fix it with a better patch, but seems that I failed ;) 
Sorry for that.

> Currently the timer is in 32 bit unchained mode, why not place it 64 bit
> mode?

Good idea! I'm not so familiar with DaVinci timer, but sounds like an 
option. This will need some changes to davinci/timer.c to handle 64bit 
timer, but this shouldn't be to hard, right?

Do you like to send a patch?

Many thanks

Dirk

> -----Original Message-----
> From: Dirk Behme [mailto:dirk.behme at googlemail.com] 
> Sent: donderdag 20 maart 2008 15:25
> To: Pieter Voorthuijsen
> Cc: u-boot-users at lists.sourceforge.net
> Subject: Re: [U-Boot-Users] DaVinci DM644x timer problem (divided by 16)
> 
> Pieter Voorthuijsen wrote:
> 
>>Hello,
>>
>>Some months ago, a patch was submitted ([ARM] fix timer overflow in 
>>DaVinci). The result was that in /cpu/arm926ejs/davinci/timer.c 
>>read_timer was divided by 16.
>>
>>http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=commit;h=ea686f52
>>e4
>>5b3df2938866d3f5a98bb2556dfe2b
>>
>>Right now, when I have my bootdelay variable (on a DVEVM) set to 2, 
>>and countdown takes 32 seconds... Also iprobe got very very  very
> 
> slow.
> 
>>Maybe more items are affected by this timer division.
>>
>>Is anybody else seeing this? Clearly when the timer is used by several
> 
> 
>>blocks, it cannot be easily divided by 16. I think we need something 
>>else to work with the wrap around of the timer...
> 
> 
> Thanks for the report!
> 
> Any idea what might be better?
> 
> Thanks
> 
> Dirk
> 





More information about the U-Boot mailing list