From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/7945 Path: news.gmane.org!not-for-mail From: Yoshinori Sato Newsgroups: gmane.linux.lib.musl.general Subject: Re: Moving forward with sh2/nommu Date: Tue, 16 Jun 2015 15:38:59 +0900 Message-ID: <871thcgnss.wl-ysato@users.sourceforge.jp> References: <20150601151107.GA20759@brightrain.aerifal.cx> <20150610033050.GS17573@brightrain.aerifal.cx> <5579085B.5090407@landley.net> <20150611151252.GW17573@brightrain.aerifal.cx> <87oakl602i.wl-ysato@users.sourceforge.jp> <20150612042821.GB17573@brightrain.aerifal.cx> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-Trace: ger.gmane.org 1434436761 15595 80.91.229.3 (16 Jun 2015 06:39:21 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 16 Jun 2015 06:39:21 +0000 (UTC) Cc: musl@lists.openwall.com, "D. Jeff Dionne" , shumpei.kawasaki@swhwc.com To: Rich Felker Original-X-From: musl-return-7958-gllmg-musl=m.gmane.org@lists.openwall.com Tue Jun 16 08:39:20 2015 Return-path: Envelope-to: gllmg-musl@m.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1Z4kWj-0004C1-RV for gllmg-musl@m.gmane.org; Tue, 16 Jun 2015 08:39:17 +0200 Original-Received: (qmail 11953 invoked by uid 550); 16 Jun 2015 06:39:16 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Original-Received: (qmail 11935 invoked from network); 16 Jun 2015 06:39:15 -0000 X-Virus-Scanned: Debian amavisd-new at sa76r4.localdomain In-Reply-To: <20150612042821.GB17573@brightrain.aerifal.cx> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM/1.14.9 (=?ISO-8859-4?Q?Goj=F2?=) APEL/10.8 EasyPG/1.0.0 Emacs/24.4 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) Xref: news.gmane.org gmane.linux.lib.musl.general:7945 Archived-At: On Fri, 12 Jun 2015 13:28:21 +0900, Rich Felker wrote: > > On Fri, Jun 12, 2015 at 01:08:05PM +0900, Yoshinori Sato wrote: > > > > >> 4. Syscall trap numbers differ on SH2 vs SH3/4. Presumably the reason > > > > >> is that these two SH2A hardware traps overlap with the syscall > > > > >> range used by SH3/4 ABI: > > > > > > > > > > I haven't patched this yet. I'd like to use 31 (0x1f) as the new > > > > > universal SH syscall trap number, instead of 22. More details on the > > > > > reasons later. > > > > > > > > I've cc'd Yoshinori Sato (who did most of the historical sh2 work) and > > > > Shumpei Kawasaki (the original superh architect). They'll probably have > > > > an opinion on your "more reasons" for changing sh2 system call numbers > > > > to match sh4. > > > > It histrical reason. > > SH3/4 is assigned #0x10 to #0x17 for system call entry. > > But SH2A system using this vector. > > So we moved to #0x20 to #0x27 for SH2A. > > (SH2A specification is #0x20 to #0x3f allocated for user application.) > > > > And SH2 port is based on SH2A port. > > It have same systemcall interface. > > > > > Thank you. I'd really like to make progress at least on the matter of > > > determining if this is feasible. I now have a new musl/sh2 patch that > > > simply uses "trapa #31" unconditionally, and it's a lot > > > simpler/cleaner and working on my patched kernel. The big question is > > > just whether this is an unacceptable constraint on hardware. > > > > SH2A reserved system for vector 31. > > But not assigned now. > > I think no problem. > > Thank you for the feedback. This sounds promising. > > We still need whoever ends up being the new kernel maintainer for SH > to be okay with adding trap 31 syscall support for sh2 and declaring > it supported/stable for sh3/4 too, but at least it looks like there > arent technical problems for doing this. > > Rich Yes. I think test necessary by SH2A, but there would be no problems. -- Yoshinori Sato