[PATCH] bsp/tms570: fix get time resolution after infrastructure change to timecounter.

Martin Galvan martin.galvan at tallertechnologies.com
Wed Jul 15 17:30:55 UTC 2015


On Wed, Jul 15, 2015 at 12:22 PM, Pavel Pisa <pisa at cmp.felk.cvut.cz> wrote:
> Patch provides way to the previous working state at least.
> I would suggest to apply this patch because current mainline is broken
> in actual state - time read goes totally unrelated to the delay functions.

Could you elaborate a bit more on why is this happening, and why does
this patch fix it? We've done some testing in the past and we never
saw such behavior. I could be wrong, though.

> It requires more changes in the code because else the tick configuration
> would be incorrect, so you read right time but all timing/delay functions
> would be 90x or so times times faster.

Does this apply to the patch as it is, or only if we keep it like it
was before? What I mean is, is there a follow-up to this patch that
fixes the issue you mention?

> As for common 1 usec, we use different
> clock (i.e. 160 MHz and even other) on different test boards so I like
> idea of common base for precise trimming and possible high resolution
> POSIX nanosleep functionality with use of fixed conversion ratio instead
> of runtime at startup computed one. We even consider lop power operation
> and have demand for such mode from carmaker.

I still don't think we should just assume 1 usec will work in every
case and happily ignore what TI gives us. But it's not up to me to
decide what goes in.



More information about the devel mailing list