Commit Graph

123 Commits

Author SHA1 Message Date
Will Deacon 3714ce1d66 iommu/arm-smmu: Disable stalling faults for all endpoints
Enabling stalling faults can result in hardware deadlock on poorly
designed systems, particularly those with a PCI root complex upstream of
the SMMU.

Although it's not really Linux's job to save hardware integrators from
their own misfortune, it *is* our job to stop userspace (e.g. VFIO
clients) from hosing the system for everybody else, even if they might
already be required to have elevated privileges.

Given that the fault handling code currently executes entirely in IRQ
context, there is nothing that can sensibly be done to recover from
things like page faults anyway, so let's rip this code out for now and
avoid the potential for deadlock.

Cc: <stable@vger.kernel.org>
Fixes: 48ec83bcbc ("iommu/arm-smmu: Add initial driver support for ARM SMMUv3 devices")
Reported-by: Matt Evans <matt.evans@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-08-19 09:48:01 +01:00
Peng Fan bee1400445 iommu/arm-smmu: Use devm_request_irq and devm_free_irq
Use devm_request_irq to simplify error handling path,
when probe smmu device.

Also devm_{request|free}_irq when init or destroy domain context.

Signed-off-by: Peng Fan <van.freenix@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-07-06 18:31:51 +01:00
Wei Chen 112c898b59 iommu/arm-smmu: request pcie devices to enable ACS
The PCIe ACS capability will affect the layout of iommu groups.
Generally speaking, if the path from root port to the PCIe device
is ACS enabled, the iommu will create a single iommu group for this
PCIe device. If all PCIe devices on the path are ACS enabled then
Linux can determine this path is ACS enabled.

Linux use two PCIe configuration registers to determine the ACS
status of PCIe devices:
ACS Capability Register and ACS Control Register.

The first register is used to check the implementation of ACS function
of a PCIe device, the second register is used to check the enable status
of ACS function. If one PCIe device has implemented and enabled the ACS
function then Linux will determine this PCIe device enabled ACS.

From the Chapter:6.12 of PCI Express Base Specification Revision 3.1a,
we can find that when a PCIe device implements ACS function, the enable
status is set to disabled by default and can be enabled by ACS-aware
software.

ACS will affect the iommu groups topology, so, the iommu driver is
ACS-aware software. This patch adds a call to pci_request_acs() to the
arm-smmu driver to enable the ACS function in PCIe devices that support
it, when they get probed.

Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Wei Chen <Wei.Chen@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-07-01 14:04:36 +01:00
Arnd Bergmann 287980e49f remove lots of IS_ERR_VALUE abuses
Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.

However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.

Andrzej Hajda has already fixed a lot of the worst abusers that
were causing actual bugs, but it would be nice to prevent any
users that are not passing 'unsigned long' arguments.

This patch changes all users of IS_ERR_VALUE() that I could find
on 32-bit ARM randconfig builds and x86 allmodconfig. For the
moment, this doesn't change the definition of IS_ERR_VALUE()
because there are probably still architecture specific users
elsewhere.

Almost all the warnings I got are for files that are better off
using 'if (err)' or 'if (err < 0)'.
The only legitimate user I could find that we get a warning for
is the (32-bit only) freescale fman driver, so I did not remove
the IS_ERR_VALUE() there but changed the type to 'unsigned long'.
For 9pfs, I just worked around one user whose calling conventions
are so obscure that I did not dare change the behavior.

I was using this definition for testing:

 #define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL && \
       unlikely((unsigned long long)(x) >= (unsigned long long)(typeof(x))-MAX_ERRNO))

which ends up making all 16-bit or wider types work correctly with
the most plausible interpretation of what IS_ERR_VALUE() was supposed
to return according to its users, but also causes a compile-time
warning for any users that do not pass an 'unsigned long' argument.

I suggested this approach earlier this year, but back then we ended
up deciding to just fix the users that are obviously broken. After
the initial warning that caused me to get involved in the discussion
(fs/gfs2/dir.c) showed up again in the mainline kernel, Linus
asked me to send the whole thing again.

[ Updated the 9p parts as per Al Viro  - Linus ]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.org/lkml/2016/1/7/363
Link: https://lkml.org/lkml/2016/5/27/486
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> # For nvmem part
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-27 15:26:11 -07:00
Linus Torvalds e7f44b65b5 Devicetree for 4.7:
- Rewrite of the unflattening code to avoid recursion and lessen the
   stack usage.
 
 - Rewrite of the phandle args parsing code to get rid of the fixed args
   size. This is needed for IOMMU code.
 
 - Sync to latest dtc which adds more dts style checking. These warnings
   are enabled with "W=1" compiles.
 
 - Tegra documentation updates related to the above warnings.
 
 - A bunch of spelling and other doc fixes.
 
 - Various vendor prefix additions.
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Merge tag 'devicetree-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull devicetree updates from Rob Herring:

 - Rewrite of the unflattening code to avoid recursion and lessen the
   stack usage.

 - Rewrite of the phandle args parsing code to get rid of the fixed args
   size.  This is needed for IOMMU code.

 - Sync to latest dtc which adds more dts style checking.  These
   warnings are enabled with "W=1" compiles.

 - Tegra documentation updates related to the above warnings.

 - A bunch of spelling and other doc fixes.

 - Various vendor prefix additions.

* tag 'devicetree-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (52 commits)
  devicetree: Add Creative Technology vendor id
  gpio: dt-bindings: add ibm,ppc4xx-gpio binding
  of/unittest: Remove unnecessary module.h header inclusion
  drivers/of: Fix build warning in populate_node()
  drivers/of: Fix depth when unflattening devicetree
  of: dynamic: changeset prop-update revert fix
  drivers/of: Export of_detach_node()
  drivers/of: Return allocated memory from of_fdt_unflatten_tree()
  drivers/of: Specify parent node in of_fdt_unflatten_tree()
  drivers/of: Rename unflatten_dt_node()
  drivers/of: Avoid recursively calling unflatten_dt_node()
  drivers/of: Split unflatten_dt_node()
  of: include errno.h in of_graph.h
  of: document refcount incrementation of of_get_cpu_node()
  Documentation: dt: soc: fix spelling mistakes
  Documentation: dt: power: fix spelling mistake
  Documentation: dt: pinctrl: fix spelling mistake
  Documentation: dt: opp: fix spelling mistake
  Documentation: dt: net: fix spelling mistakes
  Documentation: dt: mtd: fix spelling mistake
  ...
2016-05-20 14:51:34 -07:00
Robin Murphy d546635731 iommu/arm-smmu: Use per-domain page sizes.
Now that we can accurately reflect the context format we choose for each
domain, do that instead of imposing the global lowest-common-denominator
restriction and potentially ending up with nothing. We currently have a
strict 1:1 correspondence between domains and context banks, so we don't
need to entertain the possibility of multiple formats _within_ a domain.

Signed-off-by: Will Deacon <will.deacon@arm.com>
[rm: split from original patch, added SMMUv3]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-05-09 19:38:39 +02:00
Joerg Roedel 8801561ce0 Merge branch 'for-joerg/arm-smmu/updates' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into arm/smmu 2016-05-09 12:03:37 +02:00
Peng Fan 3ca3712a42 iommu/arm-smmu: Clear cache lock bit of ACR
According MMU-500r2 TRM, section 3.7.1 Auxiliary Control registers,
You can modify ACTLR only when the ACR.CACHE_LOCK bit is 0.

So before clearing ARM_MMU500_ACTLR_CPRE of each context bank,
need clear CACHE_LOCK bit of ACR register first.

Since CACHE_LOCK bit is only present in MMU-500r2 onwards,
need to check the major number of IDR7.

Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Peng Fan <van.freenix@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03 18:23:04 +01:00
Robin Murphy b7862e3559 iommu/arm-smmu: Support SMMUv1 64KB supplement
The 64KB Translation Granule Supplement to the SMMUv1 architecture
allows an SMMUv1 implementation to support 64KB pages for stage 2
translations, using a constrained VMSAv8 descriptor format limited
to 40-bit addresses. Now that we can freely mix and match context
formats, we can actually handle having 4KB pages via an AArch32
context but 64KB pages via an AArch64 context, so plumb it in.

It is assumed that any implementations will have hardware capabilities
matching the format constraints, thus obviating the need for excessive
sanity-checking; this is the case for MMU-401, the only ARM Ltd.
implementation.

CC: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03 18:23:03 +01:00
Robin Murphy 7602b87106 iommu/arm-smmu: Decouple context format from kernel config
The way the driver currently forces an AArch32 or AArch64 context format
based on the kernel config and SMMU architecture version is suboptimal,
in that it makes it very hard to support oddball mix-and-match cases
like the SMMUv1 64KB supplement, or situations where the reduced table
depth of an AArch32 short descriptor context may be desirable under an
AArch64 kernel. It also only happens to work on current implementations
which do support all the relevant formats.

Introduce an explicit notion of context format, so we can manage that
independently and get rid of the inflexible #ifdeffery.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03 18:23:03 +01:00
Robin Murphy f9a05f05b1 iommu/arm-smmu: Tidy up 64-bit/atomic I/O accesses
With {read,write}q_relaxed now able to fall back to the common
nonatomic-hi-lo helper, make use of that so that we don't have to
open-code our own. In the process, also convert the other remaining
split accesses, and repurpose the custom accessor to smooth out the
couple of troublesome instances where we really want to avoid
nonatomic writes (and a 64-bit access is unnecessary in the 32-bit
context formats we would use on a 32-bit CPU).

This paves the way for getting rid of some of the assumptions currently
baked into the driver which make it really awkward to use 32-bit context
formats with SMMUv2 under a 64-bit kernel.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03 18:23:03 +01:00
Robin Murphy f0cfffc48c iommu/arm-smmu: Work around MMU-500 prefetch errata
MMU-500 erratum #841119 is tickled by a particular set of circumstances
interacting with the next-page prefetcher. Since said prefetcher is
quite dumb and actually detrimental to performance in some cases (by
causing unwanted TLB evictions for non-sequential access patterns), we
lose very little by turning it off, and what we gain is a guarantee that
the erratum is never hit.

As a bonus, the same workaround will also prevent erratum #826419 once
v7 short descriptor support is implemented.

CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03 18:23:02 +01:00
Robin Murphy e086d912d4 iommu/arm-smmu: Convert ThunderX workaround to new method
With a framework for implementation-specific funtionality in place, the
currently-FDT-dependent ThunderX workaround gets to be the first user.

Acked-by: Tirumalesh Chalamarla <tchalamarla@caviumnetworks.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03 18:23:02 +01:00
Robin Murphy 67b65a3fb8 iommu/arm-smmu: Differentiate specific implementations
As the inevitable reality of implementation-specific errata workarounds
begin to accrue alongside our integration quirk handling, it's about
time the driver had a decent way of keeping track. Extend the per-SMMU
data so we can identify specific implementations in an efficient and
firmware-agnostic manner.

Acked-by: Tirumalesh Chalamarla <tchalamarla@caviumnetworks.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03 18:23:01 +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
Tirumalesh Chalamarla 4e3e9b6997 iommu/arm-smmu: Add support for 16 bit VMID
This patch adds support for 16-bit VMIDs on implementations of SMMUv2
that support it.

Signed-off-by: Tirumalesh Chalamarla <tchalamarla@caviumnetworks.com>
[will: commit messsage and comments]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03 18:23:00 +01:00
Robin Murphy 9800699c64 iommu/arm-smmu: Don't allocate resources for bypass domains
Until we get fully plumbed into of_iommu_configure, our default
IOMMU_DOMAIN_DMA domains just bypass translation. Since we achieve that
by leaving the stream table entries set to bypass instead of pointing at
a translation context, the context bank we allocate for the domain is
completely wasted. Context banks are typically a rather limited
resource, so don't hog ones we don't need.

Reported-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-04-21 16:47:32 +02:00
Will Deacon 5f634956cc iommu/arm-smmu: Fix stream-match conflict with IOMMU_DOMAIN_DMA
Commit cbf8277ef4 ("iommu/arm-smmu: Treat IOMMU_DOMAIN_DMA as bypass
for now") ignores requests to attach a device to the default domain
since, without IOMMU-basked DMA ops available everywhere, the default
domain will just lead to unexpected transaction faults being reported.

Unfortunately, the way this was implemented on SMMUv2 causes a
regression with VFIO PCI device passthrough under KVM on AMD Seattle.
On this system, the host controller device is associated with both a
pci_dev *and* a platform_device, and can therefore end up with duplicate
SMR entries, resulting in a stream-match conflict at runtime.

This patch amends the original fix so that attaching to IOMMU_DOMAIN_DMA
is rejected even before configuring the SMRs. This restores the old
behaviour for now, but we'll need to look at handing host controllers
specially when we come to supporting the default domain fully.

Reported-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-04-21 16:47:32 +02:00
Joerg Roedel cb6c27bb09 iommu/arm-smmu: Make use of phandle iterators in device-tree parsing
Remove the usage of of_parse_phandle_with_args() and replace
it by the phandle-iterator implementation so that we can
parse out all of the potentially present 128 stream-ids.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2016-04-19 17:25:15 -05:00
Will Deacon cbf8277ef4 iommu/arm-smmu: Treat IOMMU_DOMAIN_DMA as bypass for now
Until all upstream devices have their DMA ops swizzled to point at the
SMMU, we need to treat the IOMMU_DOMAIN_DMA domain as bypass to avoid
putting devices into an empty address space when detaching from VFIO.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-18 15:02:44 +00:00
Will Deacon bc7f2ce0a7 iommu/arm-smmu: Don't fail device attach if already attached to a domain
The ARM SMMU attach_dev implementations returns -EEXIST if the device
being attached is already attached to a domain. This doesn't play nicely
with the default domain, resulting in splats such as:

  WARNING: at drivers/iommu/iommu.c:1257
  Modules linked in:

  CPU: 3 PID: 1939 Comm: virtio-net-tx Tainted: G S              4.5.0-rc4+ #1
  Hardware name: FVP Base (DT)
  task: ffffffc87a9d0000 ti: ffffffc07a278000 task.ti: ffffffc07a278000
  PC is at __iommu_detach_group+0x68/0xe8
  LR is at __iommu_detach_group+0x48/0xe8

This patch fixes the problem by forcefully detaching the device from
its old domain, if present, when attaching to a new one. The unused
->detach_dev callback is also removed the iommu_ops structures.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-18 15:02:44 +00:00
Robin Murphy 25a1c96cd2 iommu/arm-smmu: Allow disabling unmatched stream bypass
Borrow the disable_bypass parameter from the SMMUv3 driver as a handy
debugging/security feature so that unmatched stream IDs (i.e. devices
not attached to an IOMMU domain) may be configured to fault.

Rather than introduce unsightly inconsistency, or repeat the existing
unnecessary use of module_param_named(), fix that as well in passing.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-18 15:02:44 +00:00
Robin Murphy 9adb95949a iommu/arm-smmu: Support DMA-API domains
With DMA mapping ops provided by the iommu-dma code, only a minimal
contribution from the IOMMU driver is needed to create a suitable
DMA-API domain for them to use. Implement this for the ARM SMMUs.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-18 15:02:43 +00:00
Robin Murphy d346180e70 iommu/arm-smmu: Treat all device transactions as unprivileged
The IOMMU API has no concept of privilege so assumes all devices and
mappings are equal, and indeed most non-CPU master devices on an AMBA
interconnect make little use of the attribute bits on the bus thus by
default perform unprivileged data accesses.

Some devices, however, believe themselves more equal than others, such
as programmable DMA controllers whose 'master' thread issues bus
transactions marked as privileged instruction fetches, while the data
accesses of its channel threads (under the control of Linux, at least)
are marked as unprivileged. This poses a problem for implementing the
DMA API on an IOMMU conforming to ARM VMSAv8, under which a page that is
unprivileged-writeable is also implicitly privileged-execute-never.
Given that, there is no one set of attributes with which iommu_map() can
implement, say, dma_alloc_coherent() that will allow every possible type
of access without something running into unexecepted permission faults.

Fortunately the SMMU architecture provides a means to mitigate such
issues by overriding the incoming attributes of a transaction; make use
of that to strip the privileged/unprivileged status off incoming
transactions, leaving just the instruction/data dichotomy which the
IOMMU API does at least understand; Four states good, two states better.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-18 15:02:42 +00:00
Robin Murphy 75df138655 iommu/arm-smmu: Invalidate TLBs properly
When invalidating an IOVA range potentially spanning multiple pages,
such as when removing an entire intermediate-level table, we currently
only issue an invalidation for the first IOVA of that range. Since the
architecture specifies that address-based TLB maintenance operations
target a single entry, an SMMU could feasibly retain live entries for
subsequent pages within that unmapped range, which is not good.

Make sure we hit every possible entry by iterating over the whole range
at the granularity provided by the pagetable implementation.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[will: added missing semicolons...]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17 12:05:35 +00:00
Robin Murphy 06c610e8f3 iommu/io-pgtable: Indicate granule for TLB maintenance
IOMMU hardware with range-based TLB maintenance commands can work
happily with the iova and size arguments passed via the tlb_add_flush
callback, but for IOMMUs which require separate commands per entry in
the range, it is not straightforward to infer the necessary granularity
when it comes to issuing the actual commands.

Add an additional argument indicating the granularity for the benefit
of drivers needing to know, and update the ARM LPAE code appropriately
(for non-leaf invalidations we currently just assume the worst-case
page granularity rather than walking the table to check).

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17 12:05:34 +00:00
Peng Fan 9a4a9d8c34 iommu/arm-smmu: Correct group reference count
The basic flow for add a device:
 arm_smmu_add_device
        |->iommu_group_get_for_dev
            |->iommu_group_get
                     return group;  (1)
            |->ops->device_group : Init/increase reference count to/by 1.
            |->iommu_group_add_device : Increase reference count by 1.
		     return group   (2)
        |->return 0;

Since we are adding one device, the flow is (2) and the group reference
count will be increased by 2. So, we need to add iommu_group_put at the
end of arm_smmu_add_device to decrease the count by 1.

Also take the failure path into consideration when fail to add a device.

Signed-off-by: Peng Fan <van.freenix@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17 12:05:33 +00:00
Markus Elfring 44830b0cbd iommu/arm-smmu: Delete an unnecessary check before free_io_pgtable_ops()
The free_io_pgtable_ops() function tests whether its argument is NULL
and then returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17 12:05:32 +00:00
Joerg Roedel b67ad2f7c7 Merge branches 'x86/vt-d', 'arm/omap', 'arm/smmu', 's390', 'core' and 'x86/amd' into next
Conflicts:
	drivers/iommu/amd_iommu_types.h
2015-11-02 20:03:34 +09:00
Joerg Roedel af65993224 iommu/arm-smmu: Switch to device_group call-back
This converts the ARM SMMU and the SMMUv3 driver to use the
new device_group call-back.

Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-22 00:00:49 +02:00
Will Deacon c88ae5de71 iommu/arm-smmu: Remove redundant calculation of gr0 base address
Since commit 1463fe44fd ("iommu/arm-smmu: Don't use VMIDs for stage-1
translations"), we don't need the GR0 base address when initialising a
context bank, so remove the useless local variable and its init code.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-15 16:29:54 +01:00
Tirumalesh Chalamarla 668b4ada1c iommu/arm-smmu: ThunderX mis-extends 64bit registers
The SMMU architecture defines two different behaviors when 64-bit
registers are written with 32-bit writes.  The first behavior causes
zero extension into the upper 32-bits.  The second behavior splits a
64-bit register into "normal" 32-bit register pairs.

On some buggy implementations, registers incorrectly zero extended
when they should instead behave as normal 32-bit register pairs.

Signed-off-by: Tirumalesh Chalamarla <tchalamarla@caviumnetworks.com>
[will: removed redundant macro parameters]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-14 13:43:51 +01:00
Fabio Estevam 077124c98d iommu/arm-smmu: Remove unneeded '0x' annotation
'%pad' automatically prints with '0x', so remove the explicit '0x'
annotation.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-14 13:43:50 +01:00
Robin Murphy 4103d662cb iommu/arm-smmu: Remove arm_smmu_flush_pgtable()
With the io-pgtable code now enforcing its own appropriate sync points,
the vestigial flush_pgtable callback becomes entirely redundant, so
remove it altogether.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-08-06 14:35:40 +01:00
Robin Murphy 2df7a25ce4 iommu/arm-smmu: Clean up DMA API usage
With the correct DMA API calls now integrated into the io-pgtable code,
let that handle the flushing of non-coherent page table updates.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-08-06 14:35:38 +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
Will Deacon d38f0ff9ab iommu/arm-smmu: Fix broken ATOS check
Commit 83a60ed8f0 ("iommu/arm-smmu: fix ARM_SMMU_FEAT_TRANS_OPS
condition") accidentally negated the ID0_ATOSNS predicate in the ATOS
feature check, causing the driver to attempt ATOS requests on SMMUv2
hardware without the ATOS feature implemented.

This patch restores the predicate to the correct value.

Cc: <stable@vger.kernel.org> # 4.0+
Reported-by: Varun Sethi <varun.sethi@freescale.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-06-29 21:57:32 +02:00
Will Deacon e3ce0c940e iommu/arm-smmu: Make force_stage module param read-only in sysfs
Changing force_stage dynamically isn't supported by the driver and it
also doesn't make a whole lot of sense to change it once the SMMU is up
and running.

This patch makes the sysfs entry for the parameter read-only.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-05-29 11:12:01 +02:00
Robin Murphy 661d962f19 iommu/arm-smmu: Fix ATS1* register writes
The ATS1* address translation registers only support being written
atomically - in SMMUv2 where they are 64 bits wide, 32-bit writes to
the lower half are automatically zero-extended, whilst 32-bit writes
to the upper half are ignored. Thus, the current logic of performing
64-bit writes as two 32-bit accesses is wrong.

Since we already limit IOVAs to 32 bits on 32-bit ARM, the lack of a
suitable writeq() implementation there is not an issue, and we only
need a little preprocessor ugliness to safely hide the 64-bit case.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-05-29 11:12:01 +02:00
Will Deacon 5dc5616ee8 iommu/arm-smmu: Fix sign-extension of upstream bus addresses at stage 1
Stage 1 translation is controlled by two sets of page tables (TTBR0 and
TTBR1) which grow up and down from zero respectively in the ARMv8
translation regime. For the SMMU, we only care about TTBR0 and, in the
case of a 48-bit virtual space, we expect to map virtual addresses 0x0
through to 0xffff_ffff_ffff.

Given that some masters may be incapable of emitting virtual addresses
targetting TTBR1 (e.g. because they sit on a 48-bit bus), the SMMU
architecture allows bit 47 to be sign-extended, halving the virtual
range of TTBR0 but allowing TTBR1 to be used. This is controlled by the
SEP field in TTBCR2.

The SMMU driver incorrectly enables this sign-extension feature, which
causes problems when userspace addresses are programmed into a master
device with the SMMU expecting to map the incoming transactions via
TTBR0; if the top bit of address is set, we will instead get a
translation fault since TTBR1 walks are disabled in the TTBCR.

This patch fixes the issue by disabling sign-extension of a fixed
virtual address bit and instead basing the behaviour on the upstream bus
size: the incoming address is zero extended unless the upstream bus is
only 49 bits wide, in which case bit 48 is used as the sign bit and is
replicated to the upper bits.

Cc: <stable@vger.kernel.org> # v4.0+
Reported-by: Varun Sethi <varun.sethi@freescale.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-05-11 18:36:20 +02:00
Joerg Roedel 7f65ef01e1 Merge branches 'iommu/fixes', 'x86/vt-d', 'x86/amd', 'arm/smmu', 'arm/tegra' and 'core' into next
Conflicts:
	drivers/iommu/amd_iommu.c
	drivers/iommu/tegra-gart.c
	drivers/iommu/tegra-smmu.c
2015-04-02 13:33:19 +02:00
Joerg Roedel 1d672638fc iommu/arm-smmu: Make use of domain_alloc and domain_free
Implement domain_alloc and domain_free iommu-ops as a
replacement for domain_init/domain_destroy.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-03-31 15:32:04 +02:00
Will Deacon 03edb2264c iommu/arm-smmu: handle multi-alias IOMMU groups for PCI devices
IOMMU groups for PCI devices can correspond to multiple DMA aliases due
to things like ACS and PCI quirks.

This patch extends the ARM SMMU ->add_device callback so that we
consider all of the DMA aliases for a PCI IOMMU group, rather than
creating a separate group for each Requester ID.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-27 13:39:36 +00:00
Robin Murphy f1d8454869 iommu/arm-smmu: set a more appropriate DMA mask
Since we use dma_map_page() as an architecture-independent means of
making page table updates visible to non-coherent SMMUs, we need to
have a suitable DMA mask set to discourage the DMA mapping layer from
creating bounce buffers and flushing those instead, if said page tables
happen to lie outside the default 32-bit mask.

Tested-by: Mitchel Humpherys <mitchelh@codeaurora.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[will: added error checking]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-27 13:39:36 +00:00
Will Deacon 4a1c93cbe9 iommu/arm-smmu: ensure CBA2R is initialised before CBAR on SMMUv2
The VMID16 (8.1) extension to SMMUv2 added a 16-bit VMID16 field to the
CBA2R registers. Unfortunately, if software writes this field as zero
after setting an 8-bit VMID in a stage-2 CBAR, then the VMID may also be
overwritten with zero on some early implementations (the architecture
was later updated to fix this issue).

This patch ensures that we initialise CBA2R before CBAR, therefore
ensuring that the VMID is set correctly.

Tested-by: Manish Jaggi <mjaggi@caviumnetworks.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-27 13:39:35 +00:00
Baptiste Reynal 83a60ed8f0 iommu/arm-smmu: fix ARM_SMMU_FEAT_TRANS_OPS condition
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>
2015-03-23 15:21:26 +01:00
Arnd Bergmann a4188beee5 iommu/arm-smmu: Avoid build warning
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>
2015-02-03 18:53:27 +01:00
Mitchel Humpherys 859a732e4f iommu/arm-smmu: add support for iova_to_phys through ATS1PR
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>
2015-01-19 18:18:38 +00:00
Mitchel Humpherys 3c8567d1ca iommu/arm-smmu: don't touch the secure STLBIALL register
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>
2015-01-19 14:46:54 +00:00
Will Deacon 518f713624 iommu/arm-smmu: make use of generic LPAE allocator
The ARM SMMU can walk LPAE page tables, so make use of the generic
allocator.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-19 14:46:45 +00:00