Hi, El Thu, Feb 25, 2010 at 08:22:59PM +0100 Alessandro Rubini ha dit:
> > i was/am working on a new version of the patch, taking into account > > your remarks about the unit of TIMER_FREQ and fixing some issues > > discussed with Alessandro Rubini off-list, who worked on a similar > > patch. > > Actually, I checked the point we disagreed about, which is the unit of > get_ticks() and get_tbclk(). You currently return hw-ticks in > get_ticks, and CONFIG_SYS_HZ (i.e. 1000) in get_tbclk. However, these > two functions are expected to be used together, so they must be > consistent in their return value. actually there is no disagreement between us, i totally agree with you that the return value of get_ticks() should be in CONFIG_SYS_HZ resolution and consistent with get_tbclk(). the patch i sent you yesterday off-list fixes exactly this. > It's true that the functions are little used (they are mostly used in > ppc code, within cpu/*/interrupts), and that's why I didn't even > provide them in cpu/arm926ejs/nomadik/timer.c. All few users assume > they are consistent, but there is no documentation: > > tornado% grep -qr get_tbclk README* doc || echo not found > not found > tornado% grep -qr get_ticks README* doc/* || echo not found > not found > > I've made a quick tour of all definitions in cpu/ and here is the result. > As you see, at91 (which you used as reference, I understand) is wrong, > while all the others use either hwticks or SYS_HZ consistently. yes, i used precisely at91 as reference, i liked it's code structure and didn't notice that it is wrong in this point. thanks for your research! -- Matthias Kaehlcke Embedded Linux Developer Barcelona We build too many walls and not enough bridges (Isaac Newton) .''`. using free software / Debian GNU/Linux | http://debian.org : :' : `. `'` gpg --keyserver pgp.mit.edu --recv-keys 47D8E5D4 `- _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot