From mboxrd@z Thu Jan 1 00:00:00 1970 From: Madhavi Manchala Subject: Re: Support for ARM940T core Samsung S3C2510A MCU under Linux Date: Wed, 23 Mar 2011 18:06:00 +0530 Message-ID: References: <4D87363A.7090209@snapgear.com> <4D89E270.1080001@snapgear.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-ww0-f44.google.com ([74.125.82.44]:46785 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932763Ab1CWMgB convert rfc822-to-8bit (ORCPT ); Wed, 23 Mar 2011 08:36:01 -0400 Received: by wwa36 with SMTP id 36so10062859wwa.1 for ; Wed, 23 Mar 2011 05:36:00 -0700 (PDT) In-Reply-To: <4D89E270.1080001@snapgear.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Greg Ungerer Cc: linux-arch@vger.kernel.org Hi Greg, Thanks for your information. On Wed, Mar 23, 2011 at 5:37 PM, Greg Ungerer wrote= : > Hi Madhavi, > > On 22/03/11 22:43, Madhavi Manchala wrote: >> >> Thank you very much for your valuable information and suggestions. >> >> On Mon, Mar 21, 2011 at 4:57 PM, Greg Ungerer =A0= wrote: >>> >>> On 19/03/11 01:54, Madhavi Manchala wrote: >>>> >>>> I have one basic question about the architecture files in Linux >>>> kernels. We have a board with Samsung S3C2510A MCU (ARM940T core) >>>> which is a no-mmu based CPU. I heard that "there was not a lot of = ARM >>>> no-mmu support at the moment" from Ben Dooks. >>> >>> The core is there, but there is very little specific machine suppor= t. >>> The one I use for testing is non-MMU ARM is the Atmel/AT91X40 (that= is >>> CONFIG_ARCH_AT91X40). I don't run it on real hardware, but on the >>> SkyEye emulator. >> >> I saw the mach-at91/at91x40.c and mach-at91/at91x40_time.c file >> sources. There is a few lines of code is available in these two file= s. >> I guess, some of the common files are there for all Atmel boards and >> that is also included as a part of at91x40 board. Am I correct? > > Yes, exactly. Much of the code is shared by all type of at91 parts, > irrespective of whether they have the MMU or not. (Most of the > internal peripherals at either the same or very similar - so > things like interrupts, etc). > > >> I found only at91_aic_init() function only called from at91x40.c fil= e. >> What about other initialization like serial etc.? =A0Is this include= d >> from common files for Atmel boards? > > Serial is a problem for this target, it is a little different > on the old at91x40 series to most of the newer at91 parts. Currently > it requires a different driver than the standard at91 serial driver. > (And that driver is not in mainline, and is not a platform type > driver either). > > >>>> So, I started developing the architecture files for my Samsung >>>> S3C2510A MCU (ARM940T core) by looking at the existing S3C2410A >>>> (ARM920 core) architecture files. Is this my porting (developing t= he >>>> architecture files) correct? >>> >>> Would make sense to start on something similar, yes. >> >> I downloaded the latest uClinux sources from >> http://sourceforge.net/projects/uclinux/files/uClinux%20Stable/ and >> the name of the file is uClinux-dist-20101026.tar.bz2. In this >> distribution, I found mach-s3c24a0, mach-s3c3410, s3c44b0x and >> mach-s5c7375 sources in linux-2.6.x/arch/arm/ directory. (Arnd asked >> me to see these sources as a reference, only). So, I am looking at >> these sources and especially s3c3410 sources as remaining are >> different like s3c24a0 is a MMU based etc. >> >>> >>>> How can I port the Linux on to my board which has a Samsung S3C251= 0A >>>> MCU (ARM940T core) which is a NO-MMU based CPU? >>>> >>>> Thanks for your suggestions / hints / comments. >>> >>> You can look at what I did with the AT91X40 for an example. >>> Or look at the patches that Ithamar Adema sent to the ARM linux >>> mailing list in the last few days for supporting the NXP LPC2K >>> family as another example (they are also non-MMU parts). >> >> As I said above, there are only two files which are related to at91x= 40 >> board. However, I found some sources for the Ithamar Adema patches a= t >> the following link. >> http://www.spinics.net/lists/arm-kernel/msg118932.html >> >> These sources (patches) are similar to samsung sources which are >> available in uClinux-dist. So, I will look into the Ithamar Adema >> patches and uClinux-dist samsung machine directory sources. Please >> suggest me. > > Looking at all of these will be useful. The AT91 changes where quite > simple due to the high degree of similarity. Do you mean similarity between AT91 and S3C2510A processors? Am I understand your statement correct? Thanks and Regards, Madhavi M. > >> My final question, All these samsung machines (s3c24a0, s3c3410, >> s3c44b0x and s5c7375) are ARM7TDMI core based MCUs. My MCU (Samsung >> s3c2510A) is a ARM9TDMI core based. So, is this porting will help? >> >> I am extreamly sorry, If I asked silly questions here. >> >> Once again, thanks for your suggestions and valuable inforamtion. > > No problem, glad to help. > > Regards > Greg > > > ---------------------------------------------------------------------= --- > Greg Ungerer =A0-- =A0Principal Engineer =A0 =A0 =A0 =A0EMAIL: =A0 =A0= gerg@snapgear.com > SnapGear Group, McAfee =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0PHO= NE: =A0 =A0 =A0 +61 7 3435 2888 > 8 Gardner Close =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0= FAX: =A0 =A0 =A0 =A0 +61 7 3217 5323 > Milton, QLD, 4064, Australia =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0WEB: http= ://www.SnapGear.com >