Use the new helpers dev_iommu_fwspec_get()/set() to access
the dev->iommu_fwspec pointer. This makes it easier to move
that pointer later into another struct.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The Kconfig currently controlling compilation of this code is:
drivers/iommu/Kconfig:config IPMMU_VMSA
drivers/iommu/Kconfig: bool "Renesas VMSA-compatible IPMMU"
...meaning that it currently is not being built as a module by anyone.
Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.
Since module_init was not even used by this driver, the init ordering
remains unchanged with this commit.
We also delete the MODULE_LICENSE tag etc. since all that information
was (or is now) contained at the top of the file in the comments.
Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code.
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: iommu@lists.linux-foundation.org
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
To avoid adding copy and pasted strcmp codes in the future,
this patch adds an array "rcar_gen3_slave_whitelist" to check
whether the device can work with the IPMMU or not.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Some R-Car Gen3 SoCs has hardware restrictions on the IPMMU. So,
to check whether this R-Car Gen3 SoC can use the IPMMU correctly,
this patch modifies the ipmmu_slave_whitelist().
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
If iommu_ops.add_device() fails, iommu_ops.domain_free() is still
called, leading to a crash, as the domain was only partially
initialized:
ipmmu-vmsa e67b0000.mmu: Cannot accommodate DMA translation for IOMMU page tables
sata_rcar ee300000.sata: Unable to initialize IPMMU context
iommu: Failed to add device ee300000.sata to group 0: -22
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000038
...
Call trace:
ipmmu_domain_free+0x1c/0xa0
iommu_group_release+0x48/0x68
kobject_put+0x74/0xe8
kobject_del.part.0+0x3c/0x50
kobject_put+0x60/0xe8
iommu_group_get_for_dev+0xa8/0x1f0
ipmmu_add_device+0x1c/0x40
of_iommu_configure+0x118/0x190
Fix this by checking if the domain's context already exists, before
trying to destroy it.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Fixes: d25a2a16f0 ('iommu: Add driver for Renesas VMSA-compatible IPMMU')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Including:
- PASID table handling updates for the Intel VT-d driver. It
implements a global PASID space now so that applications
usings multiple devices will just have one PASID.
- A new config option to make iommu passthroug mode the default.
- New sysfs attribute for iommu groups to export the type of the
default domain.
- A debugfs interface (for debug only) usable by IOMMU drivers
to export internals to user-space.
- R-Car Gen3 SoCs support for the ipmmu-vmsa driver
- The ARM-SMMU now aborts transactions from unknown devices and
devices not attached to any domain.
- Various cleanups and smaller fixes all over the place.
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Merge tag 'iommu-updates-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:
- PASID table handling updates for the Intel VT-d driver. It implements
a global PASID space now so that applications usings multiple devices
will just have one PASID.
- A new config option to make iommu passthroug mode the default.
- New sysfs attribute for iommu groups to export the type of the
default domain.
- A debugfs interface (for debug only) usable by IOMMU drivers to
export internals to user-space.
- R-Car Gen3 SoCs support for the ipmmu-vmsa driver
- The ARM-SMMU now aborts transactions from unknown devices and devices
not attached to any domain.
- Various cleanups and smaller fixes all over the place.
* tag 'iommu-updates-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (42 commits)
iommu/omap: Fix cache flushes on L2 table entries
iommu: Remove the ->map_sg indirection
iommu/arm-smmu-v3: Abort all transactions if SMMU is enabled in kdump kernel
iommu/arm-smmu-v3: Prevent any devices access to memory without registration
iommu/ipmmu-vmsa: Don't register as BUS IOMMU if machine doesn't have IPMMU-VMSA
iommu/ipmmu-vmsa: Clarify supported platforms
iommu/ipmmu-vmsa: Fix allocation in atomic context
iommu: Add config option to set passthrough as default
iommu: Add sysfs attribyte for domain type
iommu/arm-smmu-v3: sync the OVACKFLG to PRIQ consumer register
iommu/arm-smmu: Error out only if not enough context interrupts
iommu/io-pgtable-arm-v7s: Abort allocation when table address overflows the PTE
iommu/io-pgtable-arm: Fix pgtable allocation in selftest
iommu/vt-d: Remove the obsolete per iommu pasid tables
iommu/vt-d: Apply per pci device pasid table in SVA
iommu/vt-d: Allocate and free pasid table
iommu/vt-d: Per PCI device pasid table interfaces
iommu/vt-d: Add for_each_device_domain() helper
iommu/vt-d: Move device_domain_info to header
iommu/vt-d: Apply global PASID in SVA
...
All iommu drivers use the default_iommu_map_sg implementation, and there
is no good reason to ever override it. Just expose it as iommu_map_sg
directly and remove the indirection, specially in our post-spectre world
where indirect calls are horribly expensive.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This fixes kernel crashing on NVIDIA Tegra if kernel is compiled in
a multiplatform configuration and IPMMU-VMSA driver is enabled.
Cc: <stable@vger.kernel.org> # v3.20+
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
When attaching a device to an IOMMU group with
CONFIG_DEBUG_ATOMIC_SLEEP=y:
BUG: sleeping function called from invalid context at mm/slab.h:421
in_atomic(): 1, irqs_disabled(): 128, pid: 61, name: kworker/1:1
...
Call trace:
...
arm_lpae_alloc_pgtable+0x114/0x184
arm_64_lpae_alloc_pgtable_s1+0x2c/0x128
arm_32_lpae_alloc_pgtable_s1+0x40/0x6c
alloc_io_pgtable_ops+0x60/0x88
ipmmu_attach_device+0x140/0x334
ipmmu_attach_device() takes a spinlock, while arm_lpae_alloc_pgtable()
allocates memory using GFP_KERNEL. Originally, the ipmmu-vmsa driver
had its own custom page table allocation implementation using
GFP_ATOMIC, hence the spinlock was fine.
Fix this by replacing the spinlock by a mutex, like the arm-smmu driver
does.
Fixes: f20ed39f53 ("iommu/ipmmu-vmsa: Use the ARM LPAE page table allocator")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The TTSEL bit of IMUCTRn register of R-Car Gen3 needs to be set
unused MMU context number even if uTLBs are disabled
(The MMUEN bit of IMUCTRn register = 0).
Since initial values of IMUCTRn.TTSEL on all IPMMU-domains are 0,
this patch adds a new feature "reserved_context" to reserve IPMMU
context number 0 as the unused MMU context.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Now that we use the driver core to stop deferred probe for missing
drivers, IOMMU_OF_DECLARE can be removed.
This is slightly less optimal than having a list of built-in drivers in
that we'll now defer probe twice before giving up. This shouldn't have a
significant impact on boot times as past discussions about deferred
probe have given no evidence of deferred probe having a substantial
impact.
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: iommu@lists.linux-foundation.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-arm-msm@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org
Cc: devicetree@vger.kernel.org
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Support the r8a77970 (R-Car V3M) and r8a77995 (R-Car D3) IPMMUs by sharing
feature flags with r8a7795 (R-Car H3) and r8a7796 (R-Car M3-W). Also update
IOMMU_OF_DECLARE to hook up the compat strings.
Based on work for the r8a7796 by Magnus Damm
[rebased on v4.17]
Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Support the r8a7796 IPMMU by sharing feature flags between
r8a7795 and r8a7796. Also update IOMMU_OF_DECLARE to hook
up the updated compat string.
[rebased on v4.17]
Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Bump up the maximum numbers of micro-TLBS to 48.
Each IPMMU device instance get micro-TLB assignment via
the "iommus" property in DT. Older SoCs tend to use a
maximum number of 32 micro-TLBs per IPMMU instance however
newer SoCs such as r8a7796 make use of up to 48 micro-TLBs.
At this point no SoC specific handling is done to validate
the maximum number of micro-TLBs, and because of that the
DT information is assumed to be within correct range for
each particular SoC.
If needed in the future SoC specific feature flags can be
added to handle the maximum number of micro-TLBs without
requiring DT changes, however at this point this does not
seem necessary.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Now that no more drivers rely on arbitrary early initialisation via an
of_iommu_init_fn hook, let's clean up the redundant remnants. The
IOMMU_OF_DECLARE() macro needs to remain for now, as the probe-deferral
mechanism has no other nice way to detect built-in drivers before they
have registered themselves, such that it can make the right decision.
Reviewed-by: Sricharan R <sricharan@codeaurora.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Having of_iommu_init() call ipmmu_init() via ipmmu_vmsa_iommu_of_setup()
does nothing that the subsys_initcall wouldn't do slightly later anyway,
since probe-deferral of masters means it is no longer critical to
register the driver super-early. Clean it up.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Tie in r8a7795 features and update the IOMMU_OF_DECLARE
compat string to include the updated compat string.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Introduce support for two bit SL0 bitfield in IMTTBCR
by using a separate feature flag.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Introduce a feature to allow opt-out of setting up
IMBUSCR. The default case is unchanged.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Write IMCTR both in the root device and the leaf node.
To allow access of IMCTR introduce the following function:
- ipmmu_ctx_write_all()
While at it also rename context functions:
- ipmmu_ctx_read() -> ipmmu_ctx_read_root()
- ipmmu_ctx_write() -> ipmmu_ctx_write_root()
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The r8a7795 IPMMU supports 40-bit bus mastering. Both
the coherent DMA mask and the streaming DMA mask are
set to unlock the 40-bit address space for coherent
allocations and streaming operations.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Hook up IOMMU_OF_DECLARE() support in case CONFIG_IOMMU_DMA
is enabled. The only current supported case for 32-bit ARM
is disabled, however for 64-bit ARM usage of OF is required.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add support for up to 8 contexts. Each context is mapped to one
domain. One domain is assigned one or more slave devices. Contexts
are allocated dynamically and slave devices are grouped together
based on which IPMMU device they are connected to. This makes slave
devices tied to the same IPMMU device share the same IOVA space.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add root device handling to the IPMMU driver by allowing certain
DT compat strings to enable has_cache_leaf_nodes that in turn will
support both root devices with interrupts and leaf devices that
face the actual IPMMU consumer devices.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Introduce struct ipmmu_features to track various hardware
and software implementation changes inside the driver for
different kinds of IPMMU hardware. Add use_ns_alias_offset
as a first example of a feature to control if the secure
register bank offset should be used or not.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The remaining difference between the ARM-specific and iommu-dma ops is
in the {add,remove}_device implementations, but even those have some
overlap and duplication. By stubbing out the few arm_iommu_*() calls,
we can get rid of the rest of the inline #ifdeffery to both simplify the
code and improve build coverage.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that the IPMMU instance pointer is the only thing remaining in the
private data structure, we no longer need the extra level of indirection
and can simply stash that directlty in the fwspec.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We go through quite the merry dance in order to find masters behind the
same IPMMU instance, so that we can ensure they are grouped together.
None of which is really necessary, since the master's private data
already points to the particular IPMMU it is associated with, and that
IPMMU instance data is the perfect place to keep track of a per-instance
group directly.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We have two implementations for ipmmu_ops->alloc depending on
CONFIG_IOMMU_DMA, the difference being whether they accept the
IOMMU_DOMAIN_DMA type or not. However, iommu_dma_get_cookie() is
guaranteed to return an error when !CONFIG_IOMMU_DMA, so if
ipmmu_domain_alloc_dma() was actually checking and handling the return
value correctly, it would behave the same as ipmmu_domain_alloc()
anyway.
Similarly for freeing; iommu_put_dma_cookie() is robust by design.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In case of error, the function iommu_group_get() returns NULL pointer
not ERR_PTR(). The IS_ERR() test in the return value check should be
replaced with NULL test.
Fixes: 3ae4729202 ("iommu/ipmmu-vmsa: Add new IOMMU_DOMAIN_DMA ops")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that the core API issues its own post-unmap TLB sync call, push that
operation out from the io-pgtable-arm internals into the users. For now,
we leave the invalidation implicit in the unmap operation, since none of
the current users would benefit much from any change to that.
CC: Magnus Damm <damm+renesas@opensource.se>
CC: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Reserving a free context is both quicker and more likely to fail
(due to limited hardware resources) than setting up a pagetable.
What is more the pagetable init/cleanup code could require
the context to be set up.
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
CC: Robin Murphy <robin.murphy@arm.com>
CC: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
CC: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Extend the driver to make use of iommu_device_sysfs_add()/remove()
functions to hook up initial sysfs support.
Suggested-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Get rid of now unused device tracking code. Future code should instead
be able to use driver_for_each_device() for this purpose.
This is a simplified version of the following patch from Robin
[PATCH] iommu/ipmmu-vmsa: Clean up group allocation
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Now when both 32-bit and 64-bit code inside the driver is using
fwspec it is possible to replace the utlb handling with fwspec ids
that get populated from ->of_xlate().
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Consolidate the 32-bit and 64-bit code to make use of fwspec instead
of archdata for the 32-bit ARM case.
This is a simplified version of the fwspec handling code from Robin
posted as [PATCH] iommu/ipmmu-vmsa: Convert to iommu_fwspec
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The 32-bit ARM code gets updated to make use of ->of_xlate() and the
code is shared between 64-bit and 32-bit ARM. The of_device_is_available()
check gets dropped since it is included in of_iommu_xlate().
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Extend the driver to make use of iommu_device_register()/unregister()
functions together with iommu_device_set_ops() and iommu_set_fwnode().
These used to be part of the earlier posted 64-bit ARM (r8a7795) series but
it turns out that these days they are required on 32-bit ARM as well.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Fix comma-instead-of-semicolon typo error present
in the latest version of the IPMMU driver.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Convert from archdata to iommu_priv via iommu_fwspec on ARM64 but
let 32-bit ARM keep on using archdata for now.
Once the 32-bit ARM code and the IPMMU driver is able to move over
to CONFIG_IOMMU_DMA=y then coverting to fwspec via ->of_xlate() will
be easy.
For now fwspec ids and num_ids are not used to allow code sharing between
32-bit and 64-bit ARM code inside the driver.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Introduce an alternative set of iommu_ops suitable for 64-bit ARM
as well as 32-bit ARM when CONFIG_IOMMU_DMA=y. Also adjust the
Kconfig to depend on ARM or IOMMU_DMA. Initialize the device
from ->xlate() when CONFIG_IOMMU_DMA=y.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Break out the domain allocation code into a separate function.
This is preparation for future code sharing.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
