Messages in this thread | | | From | Arnd Bergmann <> | Subject | Re: [PATCH v5 21/29] nios2: Time keeping | Date | Tue, 28 Oct 2014 10:23:37 +0100 |
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On Tuesday 28 October 2014 10:46:29 Ley Foon Tan wrote: > On Sun, Oct 26, 2014 at 5:10 AM, Thomas Gleixner <tglx@linutronix.de> wrote: > > On Fri, 24 Oct 2014, Ley Foon Tan wrote: > >> +#ifndef _ASM_NIOS2_TIMEX_H > >> +#define _ASM_NIOS2_TIMEX_H > >> + > >> +typedef unsigned long cycles_t; > >> + > >> +extern cycles_t get_cycles(void); > >> + > >> +#define ARCH_HAS_READ_CURRENT_TIMER > > > > Why does NIOS need that? Does it have a hardware implementation > > dependent clock frequency which needs to be calibrated at boot time? > This is suggestion from Arnd to use read_current_timer instead of using > expensive delay loop calibration during boot.
My mistake, sorry. I think the right way is to define calibrate_delay_is_known() rather than read_current_timer(), I was getting confused by the ARM implementation that does both.
Arnd
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