| Message ID | 1455065878-11906-2-git-send-email-niklas.soderlund+renesas@ragnatech.se (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Niklas, Thank you for the patch. On Wednesday 10 February 2016 01:57:51 Niklas Söderlund wrote: > From: Robin Murphy <robin.murphy@arm.com> > > 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 <robin.murphy@arm.com> > Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Answering the question from the cover letter, yes, it's totally fine to pick the ack, that's actually expected. > --- > drivers/iommu/io-pgtable-arm.c | 4 +++- > include/linux/iommu.h | 1 + You might be asked to split this patch in two. > 2 files changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c > index 381ca5a..3ff4f87 100644 > --- a/drivers/iommu/io-pgtable-arm.c > +++ b/drivers/iommu/io-pgtable-arm.c > @@ -364,7 +364,9 @@ 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;
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c index 381ca5a..3ff4f87 100644 --- a/drivers/iommu/io-pgtable-arm.c +++ b/drivers/iommu/io-pgtable-arm.c @@ -364,7 +364,9 @@ 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;