This patch is a fix to "iommu/arm-smmu: add support for iova_to_phys
through ATS1PR".
According to ARM documentation, translation registers are optional even
in SMMUv1, so ID0_S1TS needs to be checked to verify their presence.
Also, we check that the domain is a stage-1 domain.
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
ARM allmodconfig gained a new warning when dma_addr_t is 32-bit wide:
drivers/iommu/arm-smmu.c: In function 'arm_smmu_iova_to_phys_hard':
drivers/iommu/arm-smmu.c:1255:3: warning: right shift count >= width of type
This changes the calculation so that the effective type is always
64-bit.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 859a732e4f ("iommu/arm-smmu: add support for iova_to_phys through ATS1PR")
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Currently, we provide the iommu_ops.iova_to_phys service by doing a
table walk in software to translate IO virtual addresses to physical
addresses. On SMMUs that support it, it can be useful to ask the SMMU
itself to do the translation. This can be used to warm the TLBs for an
SMMU. It can also be useful for testing and hardware validation.
Since the address translation registers are optional on SMMUv2, only
enable hardware translations when using SMMUv1 or when SMMU_IDR0.S1TS=1
and SMMU_IDR0.ATOSNS=0, as described in the ARM SMMU v1-v2 spec.
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
[will: reworked on top of generic iopgtbl changes]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Currently we do a STLBIALL when we initialize the SMMU. However, in
some configurations that register is not supposed to be touched and is
marked as "Secure only" in the spec. Rip it out.
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Here's the set of driver core patches for 3.19-rc1.
They are dominated by the removal of the .owner field in platform
drivers. They touch a lot of files, but they are "simple" changes, just
removing a line in a structure.
Other than that, a few minor driver core and debugfs changes. There are
some ath9k patches coming in through this tree that have been acked by
the wireless maintainers as they relied on the debugfs changes.
Everything has been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core update from Greg KH:
"Here's the set of driver core patches for 3.19-rc1.
They are dominated by the removal of the .owner field in platform
drivers. They touch a lot of files, but they are "simple" changes,
just removing a line in a structure.
Other than that, a few minor driver core and debugfs changes. There
are some ath9k patches coming in through this tree that have been
acked by the wireless maintainers as they relied on the debugfs
changes.
Everything has been in linux-next for a while"
* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
fs: debugfs: add forward declaration for struct device type
firmware class: Deletion of an unnecessary check before the function call "vunmap"
firmware loader: fix hung task warning dump
devcoredump: provide a one-way disable function
device: Add dev_<level>_once variants
ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
ath: use seq_file api for ath9k debugfs files
debugfs: add helper function to create device related seq_file
drivers/base: cacheinfo: remove noisy error boot message
Revert "core: platform: add warning if driver has no owner"
drivers: base: support cpu cache information interface to userspace via sysfs
drivers: base: add cpu_device_create to support per-cpu devices
topology: replace custom attribute macros with standard DEVICE_ATTR*
cpumask: factor out show_cpumap into separate helper function
driver core: Fix unbalanced device reference in drivers_probe
driver core: fix race with userland in device_add()
sysfs/kernfs: make read requests on pre-alloc files use the buffer.
sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
fs: sysfs: return EGBIG on write if offset is larger than file size
...
When domains are set with the DOMAIN_ATTR_NESTING flag, we must ensure
that we allocate them to stage-2 context banks if the hardware permits
it.
This patch adds support for the attribute to the ARM SMMU driver, with
the actual stage being determined depending on the features supported
by the hardware.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Currently the driver registers IOMMU bus operations for all busses even
if no ARM SMMU is present on a system. Depending on the driver probing
order this prevents the driver for the real IOMMU to register itself as
the bus-wide IOMMU.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The ARM SMMU supports the IOMMU_NOEXEC protection flag. Add the
corresponding IOMMU capability.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Exposing the XN flag of the SMMU driver as IOMMU_NOEXEC instead of
IOMMU_EXEC makes it enforceable, since for IOMMUs that don't support
the XN flag pages will always be executable.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Mapping and unmapping are more often than not in the critical path.
map_sg allows IOMMU driver implementations to optimize the process
of mapping buffers into the IOMMU page tables.
Instead of mapping a buffer one page at a time and requiring potentially
expensive TLB operations for each page, this function allows the driver
to map all pages in one go and defer TLB maintenance until after all
pages have been mapped.
Additionally, the mapping operation would be faster in general since
clients does not have to keep calling map API over and over again for
each physically contiguous chunk of memory that needs to be mapped to a
virtually contiguous region.
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Make of_device_id array const, because all OF functions handle it as const.
Signed-off-by: Kiran Padwal <kiran.padwal@smartplayin.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
We are using the same pfn for every pte we create while constructing the
pmd. Fix this by actually updating the pfn on each iteration of the pmd
construction loop.
It's not clear if we can actually hit this bug right now since iommu_map
splits up the calls to .map based on the page size, so we only ever seem to
iterate this loop once. However, things might change in the future that
might cause us to hit this.
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
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>
The SMMU driver was relying on a quirk of MMU-500 r2px to identify
the correct architecture version. Since this does not apply to other
implementations, make the architecture version for each supported
implementation explicit.
While we're at it, remove the unnecessary #ifdef since the dependencies
for CONFIG_ARM_SMMU already imply CONFIG_OF.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
In order for nested translation to work correctly, we need to ensure
that the maximum output address size from stage-1 is <= the maximum
supported input address size to stage-2. The latter is currently defined
by VA_BITS, since we make use of the CPU page table functions for
allocating out tables and so the driver currently enforces this
restriction by truncating the stage-1 output size during probe.
In reality, this doesn't make a lot of sense; the guest OS is responsible
for managing the stage-1 page tables, so we actually just need to ensure
that the ID registers of the virtual SMMU interface only advertise the
supported stage-2 input size.
This patch fixes the problem by treating the stage-1 and stage-2 input
address sizes separately.
Reported-by: Tirumalesh Chalamarla <tchalamarla@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Arbitrary integer division is not available in all ARM CPUs, so the GCC
may spit out calls to helper functions which are not implemented in
the kernel.
This patch avoids these problems in the SMMU driver by using page shift
instead of page size, so that divisions by the page size (as required
by the vSMMU code) can be expressed as a simple right shift.
Signed-off-by: Will Deacon <will.deacon@arm.com>
In preparation for nested translation support, stick a pointer to the
iommu_domain in dev->archdata.iommu. This makes it much easier to grab
hold of the physical group configuration (e.g. cbndx) when dealing with
vSMMU accesses from a guest.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Whilst the driver currently creates one IOMMU group per device, this
will soon change when we start supporting non-transparent PCI bridges
which require all upstream masters to be assigned to the same address
space.
This patch reworks our IOMMU group code so that we can easily support
multi-master groups. The master configuration (streamids and smrs) is
stored as private iommudata on the group, whilst the low-level attach/detach
code is updated to avoid double alloc/free when dealing with multiple
masters sharing the same SMMU configuration. This unifies device
handling, regardless of whether the device sits on the platform or pci
bus.
Signed-off-by: Will Deacon <will.deacon@arm.com>
When debugging and testing code on an SMMU that supports nested
translation, it can be useful to restrict the driver to a particular
stage of translation.
This patch adds a module parameter to the ARM SMMU driver to allow this
by restricting the ability of the probe() code to detect support for
only the specified stage.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Working out the usable address sizes for the SMMU is surprisingly tricky.
We must take into account both the limitations of the hardware for VA,
IPA and PA sizes but also any restrictions imposed by the Linux page
table code, particularly when dealing with nested translation (where the
IPA size is limited by the input address size at stage-2).
This patch fixes a few corner cases in our address size handling so that
we correctly deal with 40-bit addresses in TTBCR2 and restrict the IPA
size differently depending on whether or not we have support for nested
translation.
Signed-off-by: Will Deacon <will.deacon@arm.com>
The prefix suggests the number should be printed in hex, so use
the %x specifier to do that.
Found by using regex suggested by Joe Perches.
Signed-off-by: Hans Wennborg <hans@hanshq.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The number of S2CR registers is not properly set when stream
matching is not supported. Fix this and add check that we do not try to
access outside of the number of S2CR regisrers.
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
[will: added missing NUMSIDB_* definitions]
Signed-off-by: Will Deacon <will.deacon@arm.com>
When we attach a device to a domain, we configure the SMRs (if we have
any) to match the Stream IDs for the corresponding SMMU master and
program the s2crs accordingly. However, on detach we tear down the s2crs
assuming stream-indexing (as opposed to stream-matching) and SMRs
assuming they are present.
This patch fixes the device detach code so that it operates as a
converse of the attach code.
Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
If split page table lock for PTE tables is enabled (CONFIG_SPLIT_PTLOCK_CPUS
<=NR_CPUS) pgtable_page_ctor() leads to non-atomic allocation for ptlock with
a spinlock held, resulting in:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 466 at kernel/locking/lockdep.c:2742 lockdep_trace_alloc+0xd8/0xf4()
DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags))
Modules linked in:
CPU: 0 PID: 466 Comm: dma0chan0-copy0 Not tainted 3.16.0-3d47efb-clean-pl330-dma_test-ve-a15-a32-slr-m
c-on-3+ #55
[<80014748>] (unwind_backtrace) from [<80011640>] (show_stack+0x10/0x14)
[<80011640>] (show_stack) from [<802bf864>] (dump_stack+0x80/0xb4)
[<802bf864>] (dump_stack) from [<8002385c>] (warn_slowpath_common+0x64/0x88)
[<8002385c>] (warn_slowpath_common) from [<80023914>] (warn_slowpath_fmt+0x30/0x40)
[<80023914>] (warn_slowpath_fmt) from [<8005d818>] (lockdep_trace_alloc+0xd8/0xf4)
[<8005d818>] (lockdep_trace_alloc) from [<800d3d78>] (kmem_cache_alloc+0x24/0x144)
[<800d3d78>] (kmem_cache_alloc) from [<800bfae4>] (ptlock_alloc+0x18/0x2c)
[<800bfae4>] (ptlock_alloc) from [<802b1ec0>] (arm_smmu_handle_mapping+0x4c0/0x690)
[<802b1ec0>] (arm_smmu_handle_mapping) from [<802b0cd8>] (iommu_map+0xe0/0x148)
[<802b0cd8>] (iommu_map) from [<80019098>] (arm_coherent_iommu_map_page+0x160/0x278)
[<80019098>] (arm_coherent_iommu_map_page) from [<801f4d78>] (dmatest_func+0x60c/0x1098)
[<801f4d78>] (dmatest_func) from [<8003f8ac>] (kthread+0xcc/0xe8)
[<8003f8ac>] (kthread) from [<8000e868>] (ret_from_fork+0x14/0x2c)
---[ end trace ce0d27e6f434acf8 ]--
Split page tables lock is not used in the driver. In fact, page tables are
guarded with domain lock, so remove calls to pgtable_page_{c,d}tor().
Cc: <stable@vger.kernel.org>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Stage-1 context banks do not have the SMMU_CBn_TCR[SL0] field since it
is only applicable to stage-2 context banks.
This patch ensures that we don't set the reserved TCR bits for stage-1
translations.
Cc: <stable@vger.kernel.org>
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
request_irq shouldn't be called from atomic context since it might
sleep, but we're calling it with a spinlock held, resulting in:
[ 9.172202] BUG: sleeping function called from invalid context at kernel/mm/slub.c:926
[ 9.182989] in_atomic(): 1, irqs_disabled(): 128, pid: 1, name: swapper/0
[ 9.189762] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G W 3.10.40-gbc1b510b-38437-g55831d3bd9-dirty #97
[ 9.199757] [<c020c448>] (unwind_backtrace+0x0/0x11c) from [<c02097d0>] (show_stack+0x10/0x14)
[ 9.208346] [<c02097d0>] (show_stack+0x10/0x14) from [<c0301d74>] (kmem_cache_alloc_trace+0x3c/0x210)
[ 9.217543] [<c0301d74>] (kmem_cache_alloc_trace+0x3c/0x210) from [<c0276a48>] (request_threaded_irq+0x88/0x11c)
[ 9.227702] [<c0276a48>] (request_threaded_irq+0x88/0x11c) from [<c0931ca4>] (arm_smmu_attach_dev+0x188/0x858)
[ 9.237686] [<c0931ca4>] (arm_smmu_attach_dev+0x188/0x858) from [<c0212cd8>] (arm_iommu_attach_device+0x18/0xd0)
[ 9.247837] [<c0212cd8>] (arm_iommu_attach_device+0x18/0xd0) from [<c093314c>] (arm_smmu_test_probe+0x68/0xd4)
[ 9.257823] [<c093314c>] (arm_smmu_test_probe+0x68/0xd4) from [<c05aadd0>] (driver_probe_device+0x12c/0x330)
[ 9.267629] [<c05aadd0>] (driver_probe_device+0x12c/0x330) from [<c05ab080>] (__driver_attach+0x68/0x8c)
[ 9.277090] [<c05ab080>] (__driver_attach+0x68/0x8c) from [<c05a92d4>] (bus_for_each_dev+0x70/0x84)
[ 9.286118] [<c05a92d4>] (bus_for_each_dev+0x70/0x84) from [<c05aa3b0>] (bus_add_driver+0x100/0x244)
[ 9.295233] [<c05aa3b0>] (bus_add_driver+0x100/0x244) from [<c05ab5d0>] (driver_register+0x9c/0x124)
[ 9.304347] [<c05ab5d0>] (driver_register+0x9c/0x124) from [<c0933088>] (arm_smmu_test_init+0x14/0x38)
[ 9.313635] [<c0933088>] (arm_smmu_test_init+0x14/0x38) from [<c0200618>] (do_one_initcall+0xb8/0x160)
[ 9.322926] [<c0200618>] (do_one_initcall+0xb8/0x160) from [<c1200b7c>] (kernel_init_freeable+0x108/0x1cc)
[ 9.332564] [<c1200b7c>] (kernel_init_freeable+0x108/0x1cc) from [<c0b924b0>] (kernel_init+0xc/0xe4)
[ 9.341675] [<c0b924b0>] (kernel_init+0xc/0xe4) from [<c0205e38>] (ret_from_fork+0x14/0x3c)
Fix this by moving the request_irq out of the critical section. This
should be okay since smmu_domain->smmu is still being protected by the
critical section. Also, we still don't program the Stream Match Register
until after registering our interrupt handler so we shouldn't be missing
any interrupts.
Cc: <stable@vger.kernel.org>
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
[will: code cleanup and fixed request_irq token parameter]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Fix some issues reported by checkpatch.pl. Mostly whitespace, but also
includes min=>min_t, kzalloc=>kcalloc, and kmalloc=>kmalloc_array.
The only issue I'm leaving alone is:
arm-smmu.c:853: WARNING: line over 80 characters
#853: FILE: arm-smmu.c:853:
+ (MAIR_ATTR_WBRWA << MAIR_ATTR_SHIFT(MAIR_ATTR_IDX_CACHE)) |
since it seems to be a case where "exceeding 80 columns significantly
increases readability and does not hide information."
(Documentation/CodingStyle).
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This structure is read-only data and should never be modified.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
If somebody attempts to check the capability of an IOMMU domain prior to
device attach, then we'll try to dereference a NULL SMMU pointer through
the SMMU domain (since we can't determine the actual SMMU instance until
we have a device attached).
This patch fixes the capability check so that non-global features are
reported as being absent when no device is attached to the domain.
Signed-off-by: Will Deacon <will.deacon@arm.com>
For an SMMU that supports both Stage-1 and Stage-2 mappings (but not
nested translation), then we should prefer stage-1 mappings as we
otherwise rely on the memory attributes of the incoming transactions
for IOMMU_CACHE mappings.
Signed-off-by: Will Deacon <will.deacon@arm.com>
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>
MSIs are just seen as bog standard memory writes by the ARM SMMU, so
they can be translated (and isolated) in the same way.
This patch adds the IOMMU_CAP_INTR_REMAP capability to the ARM SMMU
driver and reworks our capabaility code so that we don't assume the
caps are organised as bits in a bitmask (since this isn't the intention).
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch extends the ARM SMMU driver so that it can handle PCI master
devices in addition to platform devices described in the device tree.
The driver is informed about the PCI host controller in the DT via a
phandle to the host controller in the mmu-masters property. The host
controller is then added to the master tree for that SMMU, just like a
normal master (although it probably doesn't advertise any StreamIDs).
When a device is added to the PCI bus, we set the archdata.iommu pointer
for that device to describe its StreamID (actually its RequesterID for
the moment). This allows us to re-use our existing data structures using
the host controller of_node for everything apart from StreamID
configuration, where we reach into the archdata for the information we
require.
Cc: Varun Sethi <varun.sethi@freescale.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
T0SZ controls the input address range for TTBR0, so use the input
address range rather than the output address range for the calculation.
For stage-2, this means using the output size of stage-1.
Signed-off-by: Will Deacon <will.deacon@arm.com>
There is already S2CR_TYPE_SHIFT in S2CR_TYPE_TRANS macro, so drop the
second shift. Note that, since S2CR_TYPE_SHIFT is 0x0, there is no
functional change introduced by this patch.
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The output size of stage-1 is currently limited by the input size of
stage-2, which is further limited by VA_BITS since we make use of the
standard pgd_alloc functions for creating page tables.
This patch ensures that we use VA_BITS instead of a hardcoded '39'
for the stage-1 output size limit.
Signed-off-by: Will Deacon <will.deacon@arm.com>
kernel panic happened when iommu_unmap a buffer larger than 2MB,
more than expected pmd entries got “invalidated”, due to a wrong range
passed to arm_smmu_alloc_init_pte. it was likely a typo, now we fix
it, passing the correct "end" address to arm_smmu_alloc_init_pte.
Signed-off-by: Bin Wang <binw@marvell.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The IOMMU core expects the unmap operation to return the number of bytes
that have been unmapped or 0 on failure, a negative return value being
treated like a number of bytes.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Commit 1463fe44fd ("iommu/arm-smmu: Don't use VMIDs for stage-1
translations") moved our TLB invalidation from context creation time to
context destruction time, but forgot to update an associated comment.
This patch fixes the broken comment.
Signed-off-by: Will Deacon <will.deacon@arm.com>
On coherent systems, publishing new page tables to the SMMU walker is
achieved with a dsb instruction. In fact, this can be a dsb(ishst) which
also provides the mandatory barrier option for arm64.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Commit 972157cac5 ("arm/smmu: Use irqsafe spinlock for domain lock")
fixed our page table locks to be the irq{save,restore} variants, since
the DMA mapping API can be invoked from interrupt context.
This patch cleans up our use of the flags variable so we can distinguish
between IRQ flags (now `flags') and pte protection bits (now `prot').
Signed-off-by: Will Deacon <will.deacon@arm.com>
In such a case we have to use secure aliases of some non-secure
registers.
This handling is switched on by DT property
"calxeda,smmu-secure-config-access" for an SMMU node.
Signed-off-by: Andreas Herrmann <andreas.herrmann@calxeda.com>
[will: merged with driver option handling patch]
Signed-off-by: Will Deacon <will.deacon@arm.com>
The DT parsing code that determines stream IDs uses
of_parse_phandle_with_args and thus MAX_MASTER_STREAMIDS
is always bound by MAX_PHANDLE_ARGS.
Signed-off-by: Andreas Herrmann <andreas.herrmann@calxeda.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
As the lock might be used through DMA-API which is allowed
in interrupt context.
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Baptiste Reynal