Hi Peter, On Mon, Jul 3, 2017 at 2:30 AM, Peter Maydell <peter.mayd...@linaro.org> wrote:
> On 2 July 2017 at 18:39, sundeep subbaraya <sundeep.l...@gmail.com> wrote: > > I figured out that systick uses cpu clock as clock source and > > system_clock_scale > > need to be set in msf2-soc.c. There is a bug in u-boot where it uses cpu > > clock as > > systick input but configures systick in external clock mode. I have > tested > > the modified > > u-boot on real hardware too and it works fine. I am calculating > > system_clock_scale > > as below: > > If CPU clock is X MHz then system_clock_scale = (1 / X) * 1000 > > > > Tested with different frequencies and they are yielding same results. > > If you calculate it like that you'll probably get rounding > errors. Better is > system_clock_scale = NANOSECONDS_PER_SECOND / freq_in_hz; > > (Our systick implementation hardwires the external clock > frequency at 1MHz, but this is not really correct, it > depends on the SoC.) > Ok. Modified as per your comment. Thanks, Sundeep > > thanks > -- PMM >