From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1KPja0-0001Gc-TZ for mharc-grub-devel@gnu.org; Sun, 03 Aug 2008 15:49:24 -0400 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KPjZz-0001Ct-6E for grub-devel@gnu.org; Sun, 03 Aug 2008 15:49:23 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KPjZw-00017x-Ta for grub-devel@gnu.org; Sun, 03 Aug 2008 15:49:22 -0400 Received: from [199.232.76.173] (port=41115 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KPjZw-00017f-Pc for grub-devel@gnu.org; Sun, 03 Aug 2008 15:49:20 -0400 Received: from aybabtu.com ([69.60.117.155]:37302) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1KPjZw-0003Cf-It for grub-devel@gnu.org; Sun, 03 Aug 2008 15:49:20 -0400 Received: from [192.168.10.10] (helo=thorin) by aybabtu.com with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.69) (envelope-from ) id 1KPjSp-0002dY-AV for grub-devel@gnu.org; Sun, 03 Aug 2008 21:41:59 +0200 Received: from rmh by thorin with local (Exim 4.63) (envelope-from ) id 1KPjYu-0003au-VQ for grub-devel@gnu.org; Sun, 03 Aug 2008 21:48:16 +0200 Date: Sun, 3 Aug 2008 21:48:16 +0200 From: Robert Millan To: The development of GRUB 2 Message-ID: <20080803194816.GA13744@thorin> References: <20080623075438.5861e6d1@gibibit.com> <878wwi6bqy.fsf@xs4all.nl> <20080704112801.470827ea@gibibit.com> <87tzekiecu.fsf@xs4all.nl> <20080728100533.19118c0b@gibibit.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080728100533.19118c0b@gibibit.com> Organization: free as in freedom X-Message-Flag: Worried about Outlook viruses? Switch to Thunderbird! www.mozilla.com/thunderbird X-Debbugs-No-Ack: true User-Agent: Mutt/1.5.13 (2006-08-11) X-detected-kernel: by monty-python.gnu.org: Genre and OS details not recognized. Subject: Re: [PATCH] High resolution time/TSC patch v3 X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GRUB 2 List-Id: The development of GRUB 2 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 03 Aug 2008 19:49:23 -0000 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."