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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT 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 8251CC43387 for ; Thu, 20 Dec 2018 15:08:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4BF0E218D8 for ; Thu, 20 Dec 2018 15:08:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545318532; bh=u7C8+QJIgZn2KTlrtx/D76/p3INt0xn1OcrxfyZdLh4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=AEyW6+vwoLFWe8MDx4a+RVOc4b+K2Umg/n+UcexwTDMxLIopakJFAEf7/TIlJdMDS QpPaKmUv8T6sS6kgL1Bkm1JMmHBjx0LshyIw/T8AMwkA6KJ+oOzp3YEVuhTCWmGEwO G4/o2YBNXI3t3EkkhPqTFW+G6GIaRIrT4HAIHOLo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731123AbeLTPIv (ORCPT ); Thu, 20 Dec 2018 10:08:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:45426 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729339AbeLTPIv (ORCPT ); Thu, 20 Dec 2018 10:08:51 -0500 Received: from localhost (173-25-171-118.client.mchsi.com [173.25.171.118]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 113FE21720; Thu, 20 Dec 2018 15:08:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545318530; bh=u7C8+QJIgZn2KTlrtx/D76/p3INt0xn1OcrxfyZdLh4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=t3lTejcIcSe52bezwm4dS/kKRDpfBUNXZY6ndRj4ppLrkT9ALXnNvD43FijXONCt3 tTs+i8Pg0gpjtu5zXPli1Jaj1UTlI2SWdHQBtyOZ1CVTtp/S/d266a21gtj67vwQaS bcwSEJtnaJLctE1ybZDPd0uUJTIeu+zwNJ/tmerA= Date: Thu, 20 Dec 2018 09:08:48 -0600 From: Bjorn Helgaas To: Robin Murphy Cc: hch@lst.de, linux-pci@vger.kernel.org, catalin.marinas@arm.com, rjw@rjwysocki.net, linux-kernel@vger.kernel.org, will.deacon@arm.com, linux-acpi@vger.kernel.org, iommu@lists.linux-foundation.org, gregkh@linuxfoundation.org, lenb@kernel.org, linux-arm-kernel@lists.infradead.org, m.szyprowski@samsung.com Subject: Re: [PATCH 2/2] ACPI / scan: Refactor _CCA enforcement Message-ID: <20181220150848.GA183878@google.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 07, 2018 at 04:31:35PM +0000, Robin Murphy wrote: > Rather than checking the DMA attribute at each callsite, just pass it > through for acpi_dma_configure() to handle directly. That can then deal > with the relatively exceptional DEV_DMA_NOT_SUPPORTED case by explicitly > installing dummy DMA ops instead of just skipping setup entirely. This > will then free up the dev->dma_ops == NULL case for some valuable > fastpath optimisations. > > CC: Rafael J. Wysocki > CC: Len Brown > CC: Greg Kroah-Hartman > CC: Bjorn Helgaas > Signed-off-by: Robin Murphy FWIW, if this hasn't been applied already (I think you targeted a DMA tree): Acked-by: Bjorn Helgaas > --- > drivers/acpi/scan.c | 5 +++++ > drivers/base/platform.c | 3 +-- > drivers/pci/pci-driver.c | 3 +-- > 3 files changed, 7 insertions(+), 4 deletions(-) > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index bd1c59fb0e17..b75ae34ed188 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -1456,6 +1456,11 @@ int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) > const struct iommu_ops *iommu; > u64 dma_addr = 0, size = 0; > > + if (attr == DEV_DMA_NOT_SUPPORTED) { > + set_dma_ops(dev, &dma_dummy_ops); > + return 0; > + } > + > iort_dma_setup(dev, &dma_addr, &size); > > iommu = iort_iommu_configure(dev); > diff --git a/drivers/base/platform.c b/drivers/base/platform.c > index 41b91af95afb..c6daca875c17 100644 > --- a/drivers/base/platform.c > +++ b/drivers/base/platform.c > @@ -1138,8 +1138,7 @@ int platform_dma_configure(struct device *dev) > ret = of_dma_configure(dev, dev->of_node, true); > } else if (has_acpi_companion(dev)) { > attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode)); > - if (attr != DEV_DMA_NOT_SUPPORTED) > - ret = acpi_dma_configure(dev, attr); > + ret = acpi_dma_configure(dev, attr); > } > > return ret; > diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c > index bef17c3fca67..f899a28b90f8 100644 > --- a/drivers/pci/pci-driver.c > +++ b/drivers/pci/pci-driver.c > @@ -1602,8 +1602,7 @@ static int pci_dma_configure(struct device *dev) > struct acpi_device *adev = to_acpi_device_node(bridge->fwnode); > enum dev_dma_attr attr = acpi_get_dma_attr(adev); > > - if (attr != DEV_DMA_NOT_SUPPORTED) > - ret = acpi_dma_configure(dev, attr); > + ret = acpi_dma_configure(dev, attr); > } > > pci_put_host_bridge_device(bridge); > -- > 2.19.1.dirty > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel