From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean-Christophe PLAGNIOL-VILLARD Date: Sat, 17 Jan 2009 11:16:51 +0000 Subject: Re: [Qemu-devel] [PATCH 1/3] sh: SE7750 board definition Message-Id: <20090117111651.GA3682@game.jcrosoft.org> List-Id: References: <4969B77E.7050206@juno.dti.ne.jp> <20090111130445.GA12080@game.jcrosoft.org> <496ABD72.20400@juno.dti.ne.jp> <20090112124949.GA14269@linux-sh.org> <496BFD30.30306@renesas.com> <496C98EB.5040309@juno.dti.ne.jp> <496E9570.2050306@renesas.com> <4971B6CE.4060009@juno.dti.ne.jp> In-Reply-To: <4971B6CE.4060009@juno.dti.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Shin-ichiro KAWASAKI Cc: Takashi Yoshii , qemu-devel@nongnu.org, "linux-sh@vger.kernel.org" >>> >>> Another reason for SE7750 is support for TOPPERS. TOPPERS is an open >>> source realtime OS. I think QEMU will be a strong tool for TOPPERS >>> developers. They already utilizes SkyEye, the ARM dedicated CPU >>> simulator for board-less development. Of course SkyEye cannot be >>> used for the work for SuperH. >>> >>> Here's the list of the CPUs and boards which can run TOPPERS. >>> http://www.toppers.jp/en/jsp-kernel-e.html >>> SE7750 is the only one board which has SuperH, can run TOPPERS, and >>> has Linux kernel's default config. >>> >>> We should focus on completing SH-Linux emulation before thinking about >>> other OSes. But if I have to add new board emulation, I think SE7750 >>> is a good choice. >> >> I understood. >> But this board can not get now and CPU is too old. >> And you don't have this. How do you develop this board and IP? >> >> # Does the development of SH of Toppers still continue? > > Right, the board's not available. It is a problem, even though > some amount of development can be done from SH-Linux source code > and chip specifications. > > I posted a mail to TOPPERS users ML, and got an advice that > the type of board is not so important to run TOPPERS kernel. > So, now I think I should not stick to SE7750. > # Development of SH Toppers seems going. my the TOPPERS dev could help us to have a common board to use it as reference >>> BTW, I have question about Qemu-sh board support. >>>> Does the developer of Qemu-SH try to support all boards? >>>> I think that it is good to make it the base of Qemu-SH by >>>> thinking about one board as virtual as MIPS. >>>> >>>> Because first of all, I am not so interested in the support of the >>>> board. >>>> I am interested in emulation of CPU and the userland. >>>> In the current situation, the number of supported real boards increases >>>> when the support of CPU increases. The code of the board enters whenever >>>> CPU is supported. >>>> I think that you should decide a virtual board of SH and switch CPU. >>>> >>>> How about you? >>> Good idea. I agree that virtual board is useful. >>> I wonder how linux kernel config will be. >>> Or on what kind of policy, its specs should be decided? >> I think that the Qemu-sh developer talk about it. >> # Though the talk might be not settled.... >> Or get from other architectures (ex. MIPS). > I guess you mean "hw/mips_mipssim.c". It seems emulate MIPSsim, the > MIPS emulator. In a same way, "hw/sh_virtual_board.c" or > "hw/sh_pseudo_machine.c" can be implemented. It will be useful to > check how SH CPU cores and its SoC internal IPs work. > >> Or I thought create of configurable mechanism to be good. > Once machine config file was discussed on this ML. > It will be useful for qemu-sh also, I think. I've in mind to use fdt to describe the board when implementating the qemu sh generic board Best Regards, J.