From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49027) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bD2Kz-0005S4-OO for qemu-devel@nongnu.org; Wed, 15 Jun 2016 00:21:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bD2Ku-0003XW-SD for qemu-devel@nongnu.org; Wed, 15 Jun 2016 00:21:56 -0400 Date: Wed, 15 Jun 2016 14:17:57 +1000 From: David Gibson Message-ID: <20160615041757.GI4882@voom.fritz.box> References: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="LmeqhziFqEm+Ep0k" Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] [Qemu-ppc] Determining interest in PPC e500spin, yield, and openpic patches List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: alarson@ddci.com Cc: qemu-devel@nongnu.org, qemu-ppc@nongnu.org --LmeqhziFqEm+Ep0k Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jun 13, 2016 at 06:08:30PM -0500, alarson@ddci.com wrote: > We've used older versions of QEMU for several years as a virtual > target for our OS. Many thanks to the community for providing this > platform. Hi, Thanks for your interest. > We've been working to get our OS running under QEMU 2.x and have > identified a few bugs in QEMU, have made some enhancements, and are > still tracking down some other curious behaviors. I'm looking for > some guidance as to how, and whether, you'd like patches for the > following. Always interested in bug fixes. The e500 support probably doesn't get a whole lot of attention these days, but you're proof that there are at least a few people who care. > 1. There is a defect in ppce500_spin.c:spin_kick() that creates an > incorrectly sized TLB entry. This was reported as bug > https://bugs.launchpad.net/qemu/+bug/1587535 I can provide a > patch if desired. Absolutely. > 2. We have implemented the PPC "yield" instruction. I can provide a > patch if desired. Sounds good. > 3. We're working on support for openpic timers. We're not finished, > but it would be helpful to know if a patch is desired or if we > should expect to maintain the changes independently. I don't see a reason we wouldn't want it, unless it's horribly invasive. By all means post patches, and I'll review as best I can. > 4. We're currently tracking down why in our e500 (both unicore and > multi-core) PPC QEMU 2.5 guest (x86 host), that with interrupts > disabled, after enabling the decrementer and issuing a "wait" > instruction QEMU continues to "busy loop", consuming an entire host > CPU doing apparently nothing. As expected, issuing a "wait" prior > to enabling the decrementer leaves the host process idle. We found > the bug in the PPC "wait" instruction implementation that was > independently reported and resolved last week, but that did not fix > the problem. We also have our OS running on the g3beige and using > MSR.POW which causes the host to "sleep", but we are having no joy > with e500 and "wait". Any pointers would be appreciated. When we > find something we'll report back. Ok. So, patches for ppc related code should be sent to myself and Alex Graf , co-maintainers for the target-ppc and related code. You should CC both qemu-ppc@nongnu.org and qemu-devel@nongnu.org. I have a (frequently rebased) git tree where I stage ppc patches at: https://github.com/dgibson/qemu/tree/ppc-for-2.7 --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --LmeqhziFqEm+Ep0k Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJXYNb1AAoJEGw4ysog2bOSGwEQAN3JfsBFE1suLIJZJvEUrhnI 6f6o1cZZ2MIWtI3nHmZJ97A7StYrOWelaphTgVBrtS5jdjo6OHyDiZP/2p+7jK7U DshHXLdzlO2jYYtlhm31Hq5ygcLrZe/oFVOJOQhK9nJcdIvgU09wDYnJ3QRDTSTb RmVESsXZkvInM1IWoTVYwunCJ0UKPr1FU26oHMUlAi0pXD0+vkXfG3qgAxLDHscK ECe7fJJt24pTeSct70Ug7vDcPzlXrBAv5DUfGVahQmd276k3HMohp4cuN8Q0zazf N2cgYvPNu+cJINmEEHaBZxHE2fXlm51lGP9WfA1JeoWG76fatsh98kS48R4vwO9E +0yWMVkDvepkf43uk6CWMOy/YOME+6FpMV+bxBt2Yk7oRJqAdUoLJj7KJOngHlE1 2G/WjNtdSLBZnjxOxu6jJ6nfbQ9Gpe4clQ6c4EEZRJpsUWqNOEhO07NBEhT0T1q3 0frdPfoeTtlg90/5KFNWV649qyvhhfqOP4ZEccHbwUeSh4m4QIl3yG9n/sfWfW4v Fnjb4CWNAH7vP8kwdIYIM6OoI4ItJnUo/M4041zlpQpuHNO50PadOKFCL0g3ByCX 0oq1FoJMVv+73IKoIACzsFBEzG8wQWksNtGZbUfkXZC4VwB0WLcyE+a6LgvVwZv/ j+0nDDVmuM6RPpWgM3oU =dQzi -----END PGP SIGNATURE----- --LmeqhziFqEm+Ep0k--