From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: Re: [PATCH v6 1/6] arm/arm64: add smccc Date: Mon, 2 Nov 2015 14:45:22 +0000 Message-ID: <20151102144521.GG29657@arm.com> References: <1446106888-8983-1-git-send-email-jens.wiklander@linaro.org> <1446106888-8983-2-git-send-email-jens.wiklander@linaro.org> <20151102115119.GB29657@arm.com> <20151102135633.GA17559@ermac> <20151102140313.GG2684@leverpostej> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20151102140313.GG2684@leverpostej> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Mark Rutland Cc: Jens Wiklander , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Arnd Bergmann , Greg Kroah-Hartman , Kees Cook , valentin.manea-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, jean-michel.delorme-qxv4g6HH51o@public.gmane.org, emmanuel.michel-qxv4g6HH51o@public.gmane.org, javier-5MUHepqpBA1BDgjK7y7TUQ@public.gmane.org, Jason Gunthorpe , Michal Simek , Rob Herring List-Id: devicetree@vger.kernel.org On Mon, Nov 02, 2015 at 02:03:13PM +0000, Mark Rutland wrote: > > > > +/** > > > > + * struct smccc_res - Result from SMC/HVC call > > > > + * @a0-a3 result values from registers 0 to 3 > > > > + */ > > > > +struct smccc_res { > > > > + unsigned long a0; > > > > + unsigned long a1; > > > > + unsigned long a2; > > > > + unsigned long a3; > > > > +}; > > > > > > Are there any endianness considerations for this structure? > > > > No, I can't find anything in the ARM SMC Calling Convention document > > indicating that. > > The calling conventions have no bearing on the structure, which is our > invention. > > We stash register values (which don't have endianness) returned by the > firmeware into the structure in the sequences above (which appear > endian-clean to me). Ah yes, the structure is populated by the kernel not the firmware, so there's nothing to worry about. Thanks for the explanation. Will -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html