Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936431AbcCQQrB (ORCPT ); Thu, 17 Mar 2016 12:47:01 -0400 Received: from galahad.ideasonboard.com ([185.26.127.97]:33785 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936309AbcCQQnZ convert rfc822-to-8bit (ORCPT ); Thu, 17 Mar 2016 12:43:25 -0400 From: Laurent Pinchart To: Niklas =?ISO-8859-1?Q?S=F6derlund?= Cc: vinod.koul@intel.com, linux-renesas-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org, iommu@lists.linux-foundation.org, robin.murphy@arm.com, geert+renesas@glider.be, linus.walleij@linaro.org, dan.j.williams@intel.com, arnd@arndb.de, linux-arch@vger.kernel.org Subject: Re: [PATCH v5 1/9] iommu: Add MMIO mapping type Date: Thu, 17 Mar 2016 13:18:36 +0200 Message-ID: <1602932.Q3715QPPaf@avalon> User-Agent: KMail/4.14.8 (Linux/4.1.15-gentoo-r1; KDE/4.14.8; x86_64; ; ) In-Reply-To: <1457404974-1800-2-git-send-email-niklas.soderlund+renesas@ragnatech.se> References: <1457404974-1800-1-git-send-email-niklas.soderlund+renesas@ragnatech.se> <1457404974-1800-2-git-send-email-niklas.soderlund+renesas@ragnatech.se> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2255 Lines: 67 Hi Niklas, Thank you for the patch. On Tuesday 08 March 2016 03:42:46 Niklas S?derlund wrote: > From: Robin Murphy > > On some platforms, MMIO regions might need slightly different treatment > compared to mapping regular memory; add the notion of MMIO mappings to > the IOMMU API's memory type flags, so that callers can let the IOMMU > drivers know to do the right thing. > > Signed-off-by: Robin Murphy > Signed-off-by: Niklas S?derlund Reviewed-by: Laurent Pinchart > --- > drivers/iommu/io-pgtable-arm.c | 9 +++++++-- > include/linux/iommu.h | 1 + > 2 files changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c > index 381ca5a..9c19989 100644 > --- a/drivers/iommu/io-pgtable-arm.c > +++ b/drivers/iommu/io-pgtable-arm.c > @@ -355,7 +355,10 @@ static arm_lpae_iopte arm_lpae_prot_to_pte(struct > arm_lpae_io_pgtable *data, if (!(prot & IOMMU_WRITE) && (prot & > IOMMU_READ)) > pte |= ARM_LPAE_PTE_AP_RDONLY; > > - if (prot & IOMMU_CACHE) > + if (prot & IOMMU_MMIO) > + pte |= (ARM_LPAE_MAIR_ATTR_IDX_DEV > + << ARM_LPAE_PTE_ATTRINDX_SHIFT); > + else if (prot & IOMMU_CACHE) > pte |= (ARM_LPAE_MAIR_ATTR_IDX_CACHE > << ARM_LPAE_PTE_ATTRINDX_SHIFT); > } else { > @@ -364,7 +367,9 @@ static arm_lpae_iopte arm_lpae_prot_to_pte(struct > arm_lpae_io_pgtable *data, pte |= ARM_LPAE_PTE_HAP_READ; > if (prot & IOMMU_WRITE) > pte |= ARM_LPAE_PTE_HAP_WRITE; > - if (prot & IOMMU_CACHE) > + if (prot & IOMMU_MMIO) > + pte |= ARM_LPAE_PTE_MEMATTR_DEV; > + else if (prot & IOMMU_CACHE) > pte |= ARM_LPAE_PTE_MEMATTR_OIWB; > else > pte |= ARM_LPAE_PTE_MEMATTR_NC; > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > index a5c539f..34b6432 100644 > --- a/include/linux/iommu.h > +++ b/include/linux/iommu.h > @@ -30,6 +30,7 @@ > #define IOMMU_WRITE (1 << 1) > #define IOMMU_CACHE (1 << 2) /* DMA cache coherency */ > #define IOMMU_NOEXEC (1 << 3) > +#define IOMMU_MMIO (1 << 4) /* e.g. things like MSI doorbells */ > > struct iommu_ops; > struct iommu_group; -- Regards, Laurent Pinchart