From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754532AbaIBP7C (ORCPT ); Tue, 2 Sep 2014 11:59:02 -0400 Received: from mail-pd0-f171.google.com ([209.85.192.171]:45438 "EHLO mail-pd0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753692AbaIBP7A (ORCPT ); Tue, 2 Sep 2014 11:59:00 -0400 Date: Tue, 2 Sep 2014 08:58:56 -0700 From: Guenter Roeck To: Xuetao Guan Cc: linux-kernel@vger.kernel.org, Guan Xuetao , Chen Gang , Grant Likely Subject: Re: =?utf-8?B?5Zue5aSN?= =?utf-8?B?77ya?= Status of 'unicore32' architecture in Linux kernel Message-ID: <20140902155856.GA16029@roeck-us.net> References: <20140831235115.GA6248@roeck-us.net> <1418547425.30923.1409666628661.JavaMail.root@bj-mail03.pku.edu.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1418547425.30923.1409666628661.JavaMail.root@bj-mail03.pku.edu.cn> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 02, 2014 at 10:03:48PM +0800, Xuetao Guan wrote: > Sorry for late reply. > > ----- Guenter Roeck 写道： > > Status of 'unicore32' architecture in Linux kernel > > -------------------------------------------------- > > > > The idea was to create a working kernel and initramfs for the ongoing Linux > > kernel test project. This summary describes the result of this effort. > > > > Overall, conclusion is that the architecture would need some work > > (both in qemu and the kernel itself) to make it testable with qemu. > > Great. And there's a lot of work to do for unicore32. > > > > > Guenter > > > > --------------------- > > Toolchain used was from [1]. I did not attempt to build my own toolchain. > > > > Configuration: > > > > make ARCH=unicore32 defconfig && make ARCH=unicore32 > > > > This configuration currently fails to build in the upstream kernel. > > A patch to fix the problem has been submitted and is pending upstream > > integration [2]. With this patch merged, the 'defconfig' image can > > be built. > > Thanks. I'll apply it in my repo. > Linus already accepted the patch upstream after I sent it to him directly, so this problem has been solved by now. > > > > ---------------- > > qemu > > > > Attempts to load the unicore32:defconfig image with qemu failed. > > > > Research points to [3], which includes a working unicore32 linux kernel > > in its linux repository [4], in branch unicore32-working. This branch > > includes a working unicore32 qemu configuration. It also includes > > a critical patch which is not available in the upstream kernel. > > Yes. And these patches need to be reviewed and reconsidered. > I'll try to do that in this month. > > > > > unicore32: Add ocd console and qemu-defconfig to support qemu simulator > > This patch adds a primitive OCD console to communicate with qemu. > > The same code is already used for early console support. > > Do you mean there's the same/similar code in QEMU. > No, I mean that the ocd functions in the linux kernel (such as ocd_putc) are used by both earlyprintk and the ocd console code. > > > > With this patch added, and with qemu_defconfig as provided by the same patch, > > it is possible to build and load a unicore32 image in qemu using the following > > qemu command line. > > > > qemu-system-unicore32 -curses -M puv3 -m 512 -kernel arch/unicore32/boot/zImage > > > > Caveats: > > - The use of -nographic instead of -curses causes a qemu crash > Yes, since qemu curses code was modified to meet the simple OCD console requirement. > The lack of support for -nographic is a problem for scripted testing. The issue is that we have to interpret console output for scripted testing, and having to go through curses makes that a bit difficult. Wonder if '-nographic' can be modeled as '-curses' with no available terminal configuration. At least in theory that should work, but executing the above command with TERM=dumb yields no output. Wonder how difficult it would be to change that. > > - The qemu emulation only accepts a built-in initramfs. > Yes, github version only support built-in initramfs. > NFS+LFS could be also supported, and puv3-pci sim should be added at first. > > > - The only working image is arch/unicore32/boot/zImage. > > All other variants, arch/unicore32/boot/Image and vmlinux, cause a crash. > > The same (or a similar) crash is also seen if I don't provide a built-in > > kernel command line and try to load zImage. > Sorry for that. That should be fixed. > > > - There is no networking. There is another patch in the github linux > > respository [4] which is not available upstream. The driver was submitted > > for integration back in 2011 [5] but it was never accepted or merged. > Yes, exactly. Too bad. Not exactly necessary for our current scope of testing, but it would be nice to be able to test networking. > Thanks Guenter. > You are welcome. Thanks for the feedback. Guenter