From mboxrd@z Thu Jan 1 00:00:00 1970 From: Edward Shao Subject: Re: BIOS and CPU C_states are strange Date: Sun, 21 Jun 2009 18:13:27 +0800 Message-ID: References: <1acba2fa0906191006i3cd5a035pf18e096fdb92e27e@mail.gmail.com> <1acba2fa0906191007l4b8d5c17id068d868e6178fb8@mail.gmail.com> <1acba2fa0906192354i3cb0f2dbp2c8abed6704db3f@mail.gmail.com> <1acba2fa0906210302x19c31974md75c72b7a171c852@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-pz0-f197.google.com ([209.85.222.197]:62839 "EHLO mail-pz0-f197.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751862AbZFUKUX convert rfc822-to-8bit (ORCPT ); Sun, 21 Jun 2009 06:20:23 -0400 Received: by pzk35 with SMTP id 35so171933pzk.33 for ; Sun, 21 Jun 2009 03:20:25 -0700 (PDT) In-Reply-To: <1acba2fa0906210302x19c31974md75c72b7a171c852@mail.gmail.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: linux-acpi@vger.kernel.org Hi~ powertop can download from http://www.lesswatts.org/projects/powertop/download/powertop-1.11.tar.g= z Sorry~I forgot the name of Intel utility. Best Regards, Edward On Sun, Jun 21, 2009 at 6:02 PM, Mahmood Naderan = wrote: > Hi, > 1- where can I find powertop source code? > 2- what is the name of intel utility in windows as you said? > -------------------------- > *Mahmood Naderan* > > > > > On Sun, Jun 21, 2009 at 2:19 PM, Edward Shao wro= te: >> Hi~ >> It's all depended on how utility to interpret raw information (both >> information reported by CPU or BIOS). >> You can check source code of powertop for detail information. >> For BIOS part, powertop checks value of mwait hint register reported >> by ACPI _CST method. >> >> As my experience, powertop will cause a misleading sometimes, >> especially for new Intel CPU. >> For example: >> BIOS engineer said they followed Intel BIOS porting guide to report = an >> accuracy C-state (C6) information via ACPI _CST method. >> However powertop said BIOS only reports C3. (but Intel utility under >> Windows said CPU can enter C6). >> >> Best Regards, >> Edward >> >> On Sat, Jun 20, 2009 at 2:54 PM, Mahmood Naderan wrote: >>> Hi, >>>> Only simple check value of edx. >>>> Well, unless CPU uses CPUID.5.EDX[31:20], the reserved area. >>> >>> You mean that powertop is not correctly reading the states? Do you >>> mean that the BIOS reports better that the CPU ? >>> >>> -------------------------- >>> *Mahmood Naderan* >>> >>> >>> >>> On Sat, Jun 20, 2009 at 7:26 AM, Edward Shao = wrote: >>>> >>>> Hi Mahmood, >>>> >>>> So far as I know, if your CPU is Intel, powertop maybe cause a mis= leading. >>>> Powertop uses CPUID.5.EDX to check CPU supported C states. >>>> According Intel's spec (Intel Processor Identification and the CPU= ID >>>> Instruction (Application Note 485), a CPU only has >>>> >>>> C0, C1, C2, C3, C4 (prior Core i7) >>>> C0, C1, C2, C6, C7 (Core i7 and subsequent) >>>> >>>> Check with source code of powertop >>>> while (edx) { >>>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0if (edx&7) >>>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0printf("C%i ", i); >>>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0edx =3D edx >> 4; >>>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0i++; >>>> =A0 =A0 =A0 =A0} >>>> Only simple check value of edx. >>>> Well, unless CPU uses CPUID.5.EDX[31:20], the reserved area. >>>> >>>> Ps: I does not check AMD's spec. >>>> >>>> Best Regards, >>>> Edward >>>> >>>> >>>> On Sat, Jun 20, 2009 at 1:07 AM, Mahmood Naderan wrote: >>>> > Hi, >>>> > I have run powertop with root permission with both AC and batter= powers. The >>>> > reported C_States are the same and strange: >>>> > >>>> > mahmood@magma:~$ sudo powertop >>>> > PowerTOP 1.11 =A0 (C) 2007, 2008 Intel Corporation >>>> > >>>> > Collecting data for 5 seconds >>>> > >>>> > Your CPU supports the following C-states : C1 C2 C3 C4 C5 C6 >>>> > Your BIOS reports the following C-states : C1 C2 C6 >>>> > >>>> > Where are C4 and C5? >>>> > >>>> > -------------------------- >>>> > *Mahmood Naderan* >>>> > -- >>>> > To unsubscribe from this list: send the line "unsubscribe linux-= acpi" in >>>> > the body of a message to majordomo@vger.kernel.org >>>> > More majordomo info at =A0http://vger.kernel.org/majordomo-info.= html >>>> > >>>> >>>> >>>> >>>> -- >>>> Best Regards, >>>> Edward >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-acp= i" in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at =A0http://vger.kernel.org/majordomo-info.htm= l >>> >> >> >> >> -- >> Best Regards, >> Edward >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-acpi"= in > the body of a message to majordomo@vger.kernel.org > More majordomo info at =A0http://vger.kernel.org/majordomo-info.html > --=20 Best Regards, Edward -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html