diff options
| author | Suthikulpanit, Suravee <Suravee.Suthikulpanit@amd.com> | 2015-06-10 16:08:53 (GMT) |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-06-15 12:40:49 (GMT) |
| commit | b6197b93fa4bcba9313cc415934e3fe27e2db9b0 (patch) | |
| tree | 8420fa14c410e23aae37f1277e5473ef047ca99d /arch/arm64/include | |
| parent | d0562674838c08ff142c0e9a8e12634e133c4361 (diff) | |
| download | linux-b6197b93fa4bcba9313cc415934e3fe27e2db9b0.tar.xz | |
arm64 : Introduce support for ACPI _CCA object
section 6.2.17 _CCA states that ARM platforms require ACPI _CCA
object to be specified for DMA-cabpable devices. Therefore, this patch
specifies ACPI_CCA_REQUIRED in arm64 Kconfig.
In addition, to handle the case when _CCA is missing, arm64 would assign
dummy_dma_ops to disable DMA capability of the device.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'arch/arm64/include')
| -rw-r--r-- | arch/arm64/include/asm/dma-mapping.h | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h index 9437e3d..f0d6d0b 100644 --- a/arch/arm64/include/asm/dma-mapping.h +++ b/arch/arm64/include/asm/dma-mapping.h @@ -18,6 +18,7 @@ #ifdef __KERNEL__ +#include <linux/acpi.h> #include <linux/types.h> #include <linux/vmalloc.h> @@ -28,13 +29,23 @@ #define DMA_ERROR_CODE (~(dma_addr_t)0) extern struct dma_map_ops *dma_ops; +extern struct dma_map_ops dummy_dma_ops; static inline struct dma_map_ops *__generic_dma_ops(struct device *dev) { - if (unlikely(!dev) || !dev->archdata.dma_ops) + if (unlikely(!dev)) return dma_ops; - else + else if (dev->archdata.dma_ops) return dev->archdata.dma_ops; + else if (acpi_disabled) + return dma_ops; + + /* + * When ACPI is enabled, if arch_set_dma_ops is not called, + * we will disable device DMA capability by setting it + * to dummy_dma_ops. + */ + return &dummy_dma_ops; } static inline struct dma_map_ops *get_dma_ops(struct device *dev) @@ -48,6 +59,9 @@ static inline struct dma_map_ops *get_dma_ops(struct device *dev) static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, struct iommu_ops *iommu, bool coherent) { + if (!acpi_disabled && !dev->archdata.dma_ops) + dev->archdata.dma_ops = dma_ops; + dev->archdata.dma_coherent = coherent; } #define arch_setup_dma_ops arch_setup_dma_ops |