public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Jon Smirl <jonsmirl@gmail.com>
To: Lee Revell <rlrevell@joe-job.com>
Cc: "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>,
	lkml <linux-kernel@vger.kernel.org>,
	Bob Picco <Robert.Picco@hp.com>
Subject: Re: Dell BIOS and HPET timer support
Date: Wed, 8 Jun 2005 21:38:04 -0400	[thread overview]
Message-ID: <9e47339105060818383e2311f@mail.gmail.com> (raw)
In-Reply-To: <1118278673.6247.32.camel@mindpipe>

On 6/8/05, Lee Revell <rlrevell@joe-job.com> wrote:
> Check the source, it's self-explanatory.  See hpet_alloc().

What is going on with do_div()? 
0x0429b17f /100000 = 69.8 in my caculator. It comes back as 0 from do_div().

[jonsmirl@jonsmirl ~]$ dmesg | grep HPET
HPET: cap 0429b17f8086a201 period 0429b17f
HPET: period 0429b17f ns 0429b17f
HPET: period 0429b17f ns 00000000
Using HPET for base-timer
Using HPET for gettimeofday
[jonsmirl@jonsmirl ~]$


	hpetp->hp_period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
	    HPET_COUNTER_CLK_PERIOD_SHIFT;
printk(KERN_ERR "HPET: cap %016llx period %08lx\n", cap, hpetp->hp_period);

	ns = hpetp->hp_period;	/* femptoseconds, 10^-15 */
printk(KERN_ERR "HPET: period %08lx ns %08lx \n", hpetp->hp_period, ns);
	do_div(ns, 1000000);	/* convert to nanoseconds, 10^-9 */
printk(KERN_ERR "HPET: period %08lx ns %08lx \n", hpetp->hp_period, ns);
	printk(KERN_INFO "hpet%d: %ldns tick, %d %d-bit timers\n",
		hpetp->hp_which, ns, hpetp->hp_ntimer,
		cap & HPET_COUNTER_SIZE_MASK ? 64 : 32);
-- 
Jon Smirl
jonsmirl@gmail.com

  reply	other threads:[~2005-06-09  1:38 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-06-08 22:55 Dell BIOS and HPET timer support Pallipadi, Venkatesh
2005-06-09  0:34 ` Jon Smirl
2005-06-09  0:57   ` Lee Revell
2005-06-09  1:38     ` Jon Smirl [this message]
  -- strict thread matches above, loose matches on Subject: below --
2005-06-09  2:06 Pallipadi, Venkatesh
2005-06-09  2:09 ` Jon Smirl
2005-06-08 20:11 Jon Smirl
2005-06-08 22:02 ` Matt Domsch
2005-06-08 22:34   ` Jon Smirl

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=9e47339105060818383e2311f@mail.gmail.com \
    --to=jonsmirl@gmail.com \
    --cc=Robert.Picco@hp.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=rlrevell@joe-job.com \
    --cc=venkatesh.pallipadi@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox