From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1bs5X4-0006vJ-Lo for ptxdist@pengutronix.de; Thu, 06 Oct 2016 12:04:06 +0200 Received: from [172.17.34.175] (unknown [172.17.34.175]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "mkl@blackshift.org", Issuer "StartCom Class 1 Primary Intermediate Client CA" (not verified)) (Authenticated sender: mkl@blackshift.org) by smtp.blackshift.org (Postfix) with ESMTPSA id C624F17A133 for ; Thu, 6 Oct 2016 10:04:04 +0000 (UTC) References: <20161004152325.GA2051@archie.localdomain> <20161005131327.mp6qo5gmpzbrt23c@pengutronix.de> <20161005155510.GA1586@archie.localdomain> <20161006063332.6emfdkityxiyf3lc@pengutronix.de> From: Marc Kleine-Budde Message-ID: Date: Thu, 6 Oct 2016 12:04:00 +0200 MIME-Version: 1.0 In-Reply-To: <20161006063332.6emfdkityxiyf3lc@pengutronix.de> Subject: Re: [ptxdist] Go in ptxdist List-Id: PTXdist Development Mailing List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: ptxdist@pengutronix.de Content-Type: multipart/mixed; boundary="===============0298583512==" Errors-To: ptxdist-bounces@pengutronix.de Sender: "ptxdist" To: ptxdist@pengutronix.de This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --===============0298583512== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="8d4rEqOf4mgXLeBSLxjBj5oQUAdNIdPnv" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --8d4rEqOf4mgXLeBSLxjBj5oQUAdNIdPnv Content-Type: multipart/mixed; boundary="oitvKTh6nQJvJcM7qHxNtrEeDeIg6pOu5"; protected-headers="v1" From: Marc Kleine-Budde To: ptxdist@pengutronix.de Message-ID: Subject: Re: [ptxdist] Go in ptxdist References: <20161004152325.GA2051@archie.localdomain> <20161005131327.mp6qo5gmpzbrt23c@pengutronix.de> <20161005155510.GA1586@archie.localdomain> <20161006063332.6emfdkityxiyf3lc@pengutronix.de> In-Reply-To: <20161006063332.6emfdkityxiyf3lc@pengutronix.de> --oitvKTh6nQJvJcM7qHxNtrEeDeIg6pOu5 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 10/06/2016 08:33 AM, Uwe Kleine-K=C3=B6nig wrote: > Hello, >=20 > On Wed, Oct 05, 2016 at 05:55:10PM +0200, Clemens Gruber wrote: >> They write: "ARM on Linux. You must run an EABI kernel. These are >> generally known as armel for softfloat (compatible with ARMv5) or armh= f >> for hardware floating point (ARMv6 and above)." >=20 > At least for Debian an ARMv6 compatible CPU (e.g. Raspberry Pi 1) canno= t > run armhf. According to https://www.debian.org/ports/: Cannot run debian's flavour of armhf, as it uses vp3 und thumb-2" > A lot of modern 32-bit ARM boards and devices ship with a > floating-point unit (FPU), but the Debian armel port doesn't > take much advantage of it. The armhf port was started to improve > this situation and also take advantage of other features of > newer ARM CPUs. The Debian armhf port requires at least an ARMv7 > CPU with Thumb-2 and VFP3-D16 floating point support. >> If you set GOARM to 6 or 7 it always creates hardfloat code. So I thin= k, >> setting it to anything else than 5 would lead to a crash on all >> architectures without a VFP unit? >=20 > Not necessarily. AFAIK given a properly configured kernel a hardfloat > instruction generates an exception that is then fixed up in the kernel.= > It's not efficient but at least it works. armel passes floating point values in the integer registers and debian's armhf passes them in floating point registers. This means you cannot mix and match armel and armhf, as the are ABI incompatible. Marc --=20 Pengutronix e.K. | Marc Kleine-Budde | Industrial Linux Solutions | Phone: +49-231-2826-924 | Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de | --oitvKTh6nQJvJcM7qHxNtrEeDeIg6pOu5-- --8d4rEqOf4mgXLeBSLxjBj5oQUAdNIdPnv Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEcBAEBCgAGBQJX9iGRAAoJED07qiWsqSVqhLEH/j/NMhxyWklNQ2UTZH7a2a5M U4CROF/hBPxgfGF3eHU91A2xPXGjQUsCROfLAes1Zj+l5bhtYPgi26j8tDdv5AGo hHcu1vxolxNIOo/VGv+0U3G/j/vhb/qbqNEGLvj9fLuV+W4NvA5k/dfHrIQzNCwV briupzZaqF0GX5ZIv12Sgtba/pfkP5XMV7QYjJKBMU4DFySMKOUZtr7LCpomYksw L/L5g66BszmMwBa2+2EboYSLAt87ZLdnS9iyMq3kj5+w8ft95xUK1WBwSk+ggp5e rn10SlenSU8DzafUAptdQIoi5zdfG44ZyYxqY5IrR/GchIPcvNqL/iXwvQ2HzP4= =tm75 -----END PGP SIGNATURE----- --8d4rEqOf4mgXLeBSLxjBj5oQUAdNIdPnv-- --===============0298583512== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KcHR4ZGlzdCBt YWlsaW5nIGxpc3QKcHR4ZGlzdEBwZW5ndXRyb25peC5kZQ== --===============0298583512==--