From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sinan Kaya Subject: Re: [PATCH V2 2/3] vfio, platform: make reset driver a requirement Date: Wed, 16 Mar 2016 10:27:24 -0400 Message-ID: <56E96D4C.3080008@codeaurora.org> References: <1457715275-11925-1-git-send-email-okaya@codeaurora.org> <1457715275-11925-3-git-send-email-okaya@codeaurora.org> <56E5A271.6000408@codeaurora.org> <56E8E2CD.3020604@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <56E8E2CD.3020604-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Eric Auger , kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, timur-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, cov-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, jcm-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org Cc: shankerd-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, vikrams-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, marc.zyngier-5wv7dgnIgG8@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, vinod.koul-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, agross-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Baptiste Reynal , Alex Williamson , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org Hi Baptiste, >> I couldn't see a reset function for AMBA devices. >> >> Is there anyway to write reset function for it? I have no experience with >> AMBA devices. > To my knowledge only the PL330 DMA controller (drivers/dma/pl330.c) was > passthrough'ed at some point, rather for development purpose than > production purpose. This was done by Virtual Open Systems (ask Baptiste > for more details). But I don't think this is really used. Are you OK with requiring reset driver for AMBA devices too? The PL330 driver won't work until a reset driver is submitted for it. >> >> Would you include a reset needed flag and just not require it for AMBA? >> (I honestly don't like this idea) >> > I think the requirement also makes sense for AMBA. > > Maybe an option would be to add a module parameter that would allow to > use the vfio platform/amba driver without reset module (with explicit > opt-in from the user). Maybe this can be done later on. I can see this flag useful for testing purposes but it should not be used in production. How about I add a module parameter which is not set by default? When set, I don't perform the reset requirement check. > > FYI I will not have access to my mailbox until the end of the week. OK, no rush. > > Best Regards > > Eric > -- Sinan Kaya Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project -- 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