From mboxrd@z Thu Jan 1 00:00:00 1970 From: Timur Tabi Subject: Re: [PATCH 2/2] dma: add Qualcomm Technologies HIDMA channel driver Date: Fri, 30 Oct 2015 16:55:16 -0500 Message-ID: <5633E744.6040202@codeaurora.org> References: <1446174501-8870-1-git-send-email-okaya@codeaurora.org> <1446174501-8870-2-git-send-email-okaya@codeaurora.org> <5741892.rRLhcI7KQG@wuerfel> <5633E442.3010003@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5633E442.3010003-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sinan Kaya , Arnd Bergmann Cc: dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cov-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, jcm-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Vinod Koul , Dan Williams , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org On 10/30/2015 04:42 PM, Sinan Kaya wrote: >> >> if (WARN_ON(!pdev->dev.dma_mask)) >> return -ENXIO; >> >> The dma mask has to always be set by the platform code before probe() >> is called. If it is not set, you are not allowed to perform DMA. > > I tested this on an ACPI platform BTW when I was working on the initial > implementation. PowerPC sets the mask to 32 bits by default: http://lxr.free-electrons.com/ident?i=arch_setup_pdev_archdata Should we do something similar in ARM64? Today, we have to manually set the DMA mask in all drivers. -- Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the 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