Commit Graph

7 Commits

Author SHA1 Message Date
Robin Murphy
d0acbb750a Docs: dt: document ARM SMMU generic binding usage
Document how the generic "iommus" binding should be used to describe ARM
SMMU stream IDs instead of the old "mmu-masters" binding.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-16 09:34:21 +01:00
Tirumalesh Chalamarla
1bd37a6835 iommu/arm-smmu: Workaround for ThunderX erratum #27704
Due to erratum #27704, the CN88xx SMMUv2 implementation supports only
shared ASID and VMID numberspaces.

This patch ensures that ASID and VMIDs are unique across all SMMU
instances on affected Cavium systems.

Signed-off-by: Tirumalesh Chalamarla <tchalamarla@caviumnetworks.com>
Signed-off-by: Akula Geethasowjanya <Geethasowjanya.Akula@caviumnetworks.com>
[will: commit message, comments and formatting]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03 18:23:01 +01:00
Robin Murphy
bae2c2d421 iommu/arm-smmu: Sort out coherency
Currently, we detect whether the SMMU has coherent page table walk
capability from the IDR0.CTTW field, and base our cache maintenance
decisions on that. In preparation for fixing the bogus DMA API usage,
however, we need to ensure that the DMA API agrees about this, which
necessitates deferring to the dma-coherent property in the device tree
for the final say.

As an added bonus, since systems exist where an external CTTW signal
has been tied off incorrectly at integration, allowing DT to override
it offers a neat workaround for coherency issues with such SMMUs.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-31 11:42:53 +01:00
Robin Murphy
d3aba0460a iommu/arm-smmu: support MMU-401
MMU-401 is similar to MMU-400, but updated with limited ARMv8 support.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-09-16 19:15:23 +01:00
Will Deacon
44680eedf9 iommu/arm-smmu: remove support for chained SMMUs
The ARM SMMU driver has supported chained SMMUs (i.e. SMMUs connected
back-to-back in series) via the smmu-parent property in device tree.
This was in anticipation of somebody building such a configuration,
however that seems not to be the case.

This patch removes the unused chained SMMU hack from the driver. We can
consider adding it back later if somebody decided they need it, but for
the time being it's just pointless mess that we're carrying in mainline.

Removal of the feature also makes migration to the generic IOMMU bindings
easier.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-07-03 15:50:22 +01:00
Andreas Herrmann
0c9d70d724 documentation/iommu: update description of ARM System MMU binding
This patch adds descriptions for new properties of the device tree
binding for the ARM SMMU architecture. These properties control
arm-smmu driver options.

Cc: Grant Likely <grant.likely@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andreas Herrmann <andreas.herrmann@calxeda.com>
[will: removed device isolation property, as this has been dropped and
       fixed up spacing in documentation]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-02-24 19:09:45 +00:00
Will Deacon
98c33c5a97 documentation/iommu: Add description of ARM System MMU binding
This patch adds a description of the device tree binding for the ARM
System MMU architecture.

Cc: Rob Herring <robherring2@gmail.com>
Cc: Andreas Herrmann <andreas.herrmann@calxeda.com>
Cc: Joerg Roedel <joro@8bytes.org>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Andreas Herrmann <andreas.herrmann@calxeda.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-06-25 23:33:43 +02:00