From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: Please help with the OMAP static mapping mess Date: Tue, 04 Oct 2011 21:09:47 -0500 Message-ID: <4E8BBC6B.7000500@gmail.com> References: <20111003205658.GJ6324@atomide.com> <20111003223824.GK6324@atomide.com> <4E8AAFF9.3090600@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-gy0-f174.google.com ([209.85.160.174]:54680 "EHLO mail-gy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753297Ab1JECJu (ORCPT ); Tue, 4 Oct 2011 22:09:50 -0400 Received: by gyg10 with SMTP id 10so1118824gyg.19 for ; Tue, 04 Oct 2011 19:09:50 -0700 (PDT) In-Reply-To: Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Nicolas Pitre Cc: Santosh Shilimkar , Tony Lindgren , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org On 10/04/2011 04:21 PM, Nicolas Pitre wrote: > On Tue, 4 Oct 2011, Santosh Shilimkar wrote: > >> On Tuesday 04 October 2011 04:08 AM, Tony Lindgren wrote: >>> * Nicolas Pitre [111003 14:36]: >>>> On Mon, 3 Oct 2011, Tony Lindgren wrote: >>>> >>>>> Having the SRAM base address move around with different sizes also >>>>> requires the SoC detection.. Otherwise we can end up mapping wrong >>>>> size and end up trying to access secure SRAM that will hang the system. >>>>> >>>>> The way to fix it is to move SRAM init happen much later so we don't >>>>> have to map it early. I guess now we could use ioremap for SRAM, >>>>> although we may not want device attributes for the executable code? >>>>> Got any suggestions here on how we should map SRAM later on? >>>> >>>> You can use a variant of ioremap() such as __arm_ioremap() which let you >>>> specify the memory attribute. >>> >>> OK, I'll take a look at that. >>> >> I have tried __arm_ioremap_pfn() for some DDR mapping and it didn't >> work as expected. The mapping was not getting created. > > Did you investigate why it wasn't created? Must have been a trivial > issue surely? But you have to wait until memory management is fully > initialized to call the real ioremap() though, which happens later > during the boot. > Isn't ioremap prevented from using main memory now? Rob From mboxrd@z Thu Jan 1 00:00:00 1970 From: robherring2@gmail.com (Rob Herring) Date: Tue, 04 Oct 2011 21:09:47 -0500 Subject: Please help with the OMAP static mapping mess In-Reply-To: References: <20111003205658.GJ6324@atomide.com> <20111003223824.GK6324@atomide.com> <4E8AAFF9.3090600@ti.com> Message-ID: <4E8BBC6B.7000500@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 10/04/2011 04:21 PM, Nicolas Pitre wrote: > On Tue, 4 Oct 2011, Santosh Shilimkar wrote: > >> On Tuesday 04 October 2011 04:08 AM, Tony Lindgren wrote: >>> * Nicolas Pitre [111003 14:36]: >>>> On Mon, 3 Oct 2011, Tony Lindgren wrote: >>>> >>>>> Having the SRAM base address move around with different sizes also >>>>> requires the SoC detection.. Otherwise we can end up mapping wrong >>>>> size and end up trying to access secure SRAM that will hang the system. >>>>> >>>>> The way to fix it is to move SRAM init happen much later so we don't >>>>> have to map it early. I guess now we could use ioremap for SRAM, >>>>> although we may not want device attributes for the executable code? >>>>> Got any suggestions here on how we should map SRAM later on? >>>> >>>> You can use a variant of ioremap() such as __arm_ioremap() which let you >>>> specify the memory attribute. >>> >>> OK, I'll take a look at that. >>> >> I have tried __arm_ioremap_pfn() for some DDR mapping and it didn't >> work as expected. The mapping was not getting created. > > Did you investigate why it wasn't created? Must have been a trivial > issue surely? But you have to wait until memory management is fully > initialized to call the real ioremap() though, which happens later > during the boot. > Isn't ioremap prevented from using main memory now? Rob