[PATCH v2 2/2] ARM: am335x: Changed timer
jlu at pengutronix.de
Fri Jul 17 02:16:14 PDT 2015
On Do, 2015-07-16 at 10:51 +0200, Daniel Schultz wrote:
> The dmtimer0 is too inaccurate to be used for measurements.
> We switch to the more accurate dmtimer2.
What are you trying to measure? Is the resolution or the accuracy too
> +#define CLK_M_OSC 25000000
> +static int dmtimer_init(void)
> + dmtimer_cs.mult = clocksource_hz2mult(CLK_M_OSC, dmtimer_cs.shift);
> + /* Enable counter */
> + writel(0x3, base + TCLR);
> + return init_clock(&dmtimer_cs);
You use a fixed M_OSC of 25 MHz, but this value actually depends on the
the board. The AM335x supports 19.2, 24 and 26 MHz in addition to 25
The advantage of using dmtimer0 is that it is always available and runs
at 32KiHz on every board.
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