From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A063BC282D7 for ; Wed, 30 Jan 2019 13:00:25 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2AF0E2175B for ; Wed, 30 Jan 2019 13:00:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2AF0E2175B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 43qNkv0VxqzDqXB for ; Thu, 31 Jan 2019 00:00:23 +1100 (AEDT) Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 43qNhx3x0qzDqCZ for ; Wed, 30 Jan 2019 23:58:41 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPSA id 43qNhx1kRdz9s9h; Wed, 30 Jan 2019 23:58:41 +1100 (AEDT) From: Michael Ellerman To: Alexander Fomichev , linuxppc-dev@lists.ozlabs.org Subject: Re: [RFC PATCH] powerpc: fix get_arch_dma_ops() for NTB devices In-Reply-To: <20190128133203.mon4a3nkrzijn43g@alfbook-pro.local> References: <20190128133203.mon4a3nkrzijn43g@alfbook-pro.local> Date: Wed, 30 Jan 2019 23:58:40 +1100 Message-ID: <87imy6pain.fsf@concordia.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Christoph Hellwig , linux@yadro.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Alexander Fomichev writes: > get_dma_ops() falls into arch-dependant get_arch_dma_ops(), which > historically returns NULL on PowerPC. Therefore dma_set_mask() fails. > This affects Switchtec (and probably other) NTB devices, that they fail > to initialize. What's an NTB device? drivers/ntb I assume? So it's a PCI device of some sort, but presumably the device you're calling dma_set_mask() on is an NTB device not a PCI device? But then it works if you tell it to use the PCI DMA ops? At the very least the code should be checking for the NTB bus type and only returning the PCI ops in that specific case, not for all devices. cheers