From mboxrd@z Thu Jan 1 00:00:00 1970 From: laurent.pinchart@ideasonboard.com (Laurent Pinchart) Date: Thu, 17 Mar 2016 13:18:36 +0200 Subject: [PATCH v5 1/9] iommu: Add MMIO mapping type 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> Message-ID: <1602932.Q3715QPPaf@avalon> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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