From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from co9outboundpool.messaging.microsoft.com (co9ehsobe001.messaging.microsoft.com [207.46.163.24]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (Client CN "mail.global.frontbridge.com", Issuer "Microsoft Secure Server Authority" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 95D5B2C00A7 for ; Sun, 7 Apr 2013 13:14:41 +1000 (EST) Received: from mail117-co9 (localhost [127.0.0.1]) by mail117-co9-R.bigfish.com (Postfix) with ESMTP id C55273000FD for ; Sun, 7 Apr 2013 03:14:36 +0000 (UTC) Received: from CO9EHSMHS005.bigfish.com (unknown [10.236.132.231]) by mail117-co9.bigfish.com (Postfix) with ESMTP id 0D58BD80056 for ; Sun, 7 Apr 2013 03:14:36 +0000 (UTC) Date: Sun, 7 Apr 2013 11:15:56 +0800 From: Zhao Chenhui To: Tang Yuantian-B29983 Subject: Re: [PATCH 08/17] powerpc/85xx: add support to JOG feature using cpufreq interface Message-ID: <20130407031556.GA17885@localhost.localdomain> References: <1364994565-16010-1-git-send-email-chenhui.zhao@freescale.com> <1364994565-16010-8-git-send-email-chenhui.zhao@freescale.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" In-Reply-To: Cc: "linuxppc-dev@lists.ozlabs.org" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sun, Apr 07, 2013 at 10:30:41AM +0800, Tang Yuantian-B29983 wrote: > Also send this patch to cpufreq@vger.kernel.org and linux-pm@vger.kerne= l.org > And better to rebase it on git://git.kernel.org/pub/scm/linux/kernel/gi= t/rafael/linux-pm.git >=20 > Thanks, > Yuantian OK. Thanks. -Chenhui >=20 > > -----Original Message----- > > From: Linuxppc-dev [mailto:linuxppc-dev- > > bounces+b29983=3Dfreescale.com@lists.ozlabs.org] On Behalf Of Zhao Ch= enhui > > Sent: 2013=E5=B9=B44=E6=9C=883=E6=97=A5 21:09 > > To: linuxppc-dev@lists.ozlabs.org > > Subject: [PATCH 08/17] powerpc/85xx: add support to JOG feature using > > cpufreq interface > >=20 > > From: chenhui zhao > >=20 > > Some MPC85xx SoCs like MPC8536 and P1022 have a JOG feature, which > > provides a dynamic mechanism to lower or raise the CPU core clock at > > runtime. > >=20 > > This patch adds the support to change CPU frequency using the standar= d > > cpufreq interface. The ratio CORE to CCB can be 1:1(except MPC8536), = 3:2, > > 2:1, 5:2, 3:1, 7:2 and 4:1. > >=20 > > Two CPU cores on P1022 must not in the low power state during the > > frequency transition. The driver uses a flag to meet the requirement. > >=20 > > The jog mode frequency transition process on the MPC8536 is similar t= o > > the deep sleep process. The driver need save the CPU state and restor= e it > > after CPU warm reset. > >=20 > > Note: > > * The I/O peripherals such as PCIe and eTSEC may lose packets during > > the jog mode frequency transition. > > * The driver doesn't support MPC8536 Rev 1.0 due to a JOG erratum. > > Subsequent revisions of MPC8536 have corrected the erratum. > >=20 > > Signed-off-by: Dave Liu > > Signed-off-by: Li Yang > > Signed-off-by: Jerry Huang > > Signed-off-by: Zhao Chenhui