From mboxrd@z Thu Jan 1 00:00:00 1970 From: Santosh Shilimkar Subject: RE: [PATCH 4/5 v2] OMAP3630: PM: Disable L2 cache while invalidating L2 cache Date: Thu, 2 Dec 2010 10:35:57 +0530 Message-ID: <68d1d4807ed2c28d3b339571601a2a7f@mail.gmail.com> References: <1291061993-4740-1-git-send-email-nm@ti.com> <1291061993-4740-5-git-send-email-nm@ti.com> <4CF507CF.30909@ti.com> <4CF65E03.103@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Return-path: Received: from na3sys009aog111.obsmtp.com ([74.125.149.205]:34479 "EHLO na3sys009aog111.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751062Ab0LBFF7 (ORCPT ); Thu, 2 Dec 2010 00:05:59 -0500 Received: by mail-qy0-f175.google.com with SMTP id 8so3462077qyk.20 for ; Wed, 01 Dec 2010 21:05:59 -0800 (PST) In-Reply-To: <4CF65E03.103@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Nishanth Menon , TAO HU Cc: TAO HU , linux-omap , Jean , Tony , Kevin , Vishwanath Sripathy , Russell King - ARM Linux > -----Original Message----- > From: linux-omap-owner@vger.kernel.org [mailto:linux-omap- > owner@vger.kernel.org] On Behalf Of Nishanth Menon > Sent: Wednesday, December 01, 2010 8:09 PM > To: TAO HU > Cc: TAO HU; linux-omap; Jean; Tony; Kevin; Vishwa > Subject: Re: [PATCH 4/5 v2] OMAP3630: PM: Disable L2 cache while > invalidating L2 cache > > TAO HU had written, on 12/01/2010 02:56 AM, the following: > > Do we need to implement the same thing in bootloader? > > I.e. Do we need to disable L2 prior invalidating L2 for OMAP3630 1st > boot up? > Though out of context for this email list (linux kernel :)), I believe > it wont hurt to do this as a standard procedure. You should always invalidate the cache before enabling it. Now if at the 1st boot-up if the ROM code / boot-loader is doing this, you don't have do it. At least from kernel point of it's responsibility of boot-loaders/boot-straps to keep the caches invalidated. That's why the generic kernel don't invalidate them before enabling them. RMK has documeneted this. Read " 2. Loader Checks" http://www.arm.linux.org.uk/developer/noboot-checklist/ Regards, Santosh