[PATCH v5 1/9] iommu: Add MMIO mapping type
From: niklas.soderlund+renesas@ragnatech.se (Niklas Söderlund)
Date: 2016-03-08 02:44:22
Also in:
linux-arch, linux-iommu, linux-renesas-soc, lkml
Subsystem:
arm smmu drivers, iommu subsystem, the rest · Maintainers:
Will Deacon, Joerg Roedel, Linus Torvalds
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> Signed-off-by: Niklas S?derlund <niklas.soderlund+renesas@ragnatech.se> --- 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;
--
2.7.2