Messages in this thread | | | Date | Thu, 15 May 2014 09:47:24 +0200 | From | Uwe Kleine-König <> | Subject | Re: [RFC PATCH 0/5] Frequency resolution in CCF vs. cpufreq |
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On Wed, May 14, 2014 at 03:30:50PM -0700, Soren Brinkmann wrote: > Hi, > > I have one or two problems with cpufreq and the CCF, which are caused by > rounding/different frequency resolutions. > > cpufreq works with kHz, while the CCF uses Hz. On Zynq our default frequency is > 666666666 Hz which the CCF, due to rounding, reports as 666666660. And for Why does this happen? Isn't that a bug? What is the actual freqency? 666666666 Hz or 2000000000/3 Hz?
> cpufreq, which simply divides values it obtains through clk_round_rate() by > 1000, 666666. > Since passing 666666 to clk_round_rate() does not result in 666666660 > (clk_round_rate() always rounds down!), we chose to put 666667 in the OPP. This What is OPP?
Best regards Uwe
-- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ | -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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