Re: [PATCH] High resolution time/TSC patch v3

[Robert Millan <rmh@aybabtu.com>]

On Mon, Jul 28, 2008 at 10:05:33AM -0700, Colin D Bennett wrote:
> +/* Calibrate the TSC based on the RTC.  */
> +static void
> +calibrate_tsc (void)
> +{
> +  /* First calbrate the TSC rate (relative, not absolute time). */
> +  grub_uint64_t start_tsc;
> +  grub_uint64_t end_tsc;
> +  grub_uint32_t initial_tick;
> +  grub_uint32_t start_tick;
> +  grub_uint32_t end_tick;
> +
> +  /* Wait for the start of the next tick;
> +     we'll base out timing off this edge. */
> +  initial_tick = grub_get_rtc ();

Ah, I see the problem.  It calls grub_get_rtc() which in grub-coreboot is just
a stub.

How about using the interval timer for calibration instead?

-- 
Robert Millan

  The DRM opt-in fallacy: "Your data belongs to us. We will decide when (and
  how) you may access your data; but nobody's threatening your freedom: we
  still allow you to remove your data and not access it at all."