Intel VT-d specification revision 3 added support for Scalable Mode
Translation for DMA remapping. Add the Scalable Mode fault reasons to
show detailed fault reasons when the translation fault happens.
Link: https://software.intel.com/sites/default/files/managed/c5/15/vt-directed-io-spec.pdf
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Signed-off-by: Kyung Min Park <kyung.min.park@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Global pages support is removed from VT-d spec 3.0. Since global pages G
flag only affects first-level paging structures and because DMA request
with PASID are only supported by VT-d spec. 3.0 and onward, we can
safely remove global pages support.
For kernel shared virtual address IOTLB invalidation, PASID
granularity and page selective within PASID will be used. There is
no global granularity supported. Without this fix, IOTLB invalidation
will cause invalid descriptor error in the queued invalidation (QI)
interface.
Fixes: 1c4f88b7f1 ("iommu/vt-d: Shared virtual address in scalable mode")
Reported-by: Sanjay K Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms and conditions of the gnu general public license
version 2 as published by the free software foundation this program
is distributed in the hope it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
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extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 33 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000435.254582722@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previously, get_valid_domain_for_dev() is used to retrieve the
DMA domain which has been attached to the device or allocate one
if no domain has been attached yet. As we have delegated the DMA
domain management to upper layer, this function is used purely to
allocate a private DMA domain if the default domain doesn't work
for ths device. Cleanup the code for readability.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
A scalable mode DMAR table walk would involve looking at bits in each stage
of walk, like,
1. Is PASID enabled in the context entry?
2. What's the size of PASID directory?
3. Is the PASID directory entry present?
4. Is the PASID table entry present?
5. Number of PASID table entries?
Hence, add these macros that will later be used during this walk.
Apart from adding new macros, move existing macros (like
pasid_pde_is_present(), get_pasid_table_from_pde() and pasid_supported())
to appropriate header files so that they could be reused.
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Sohil Mehta <sohil.mehta@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
When multiple domains per device has been enabled by the
device driver, the device will tag the default PASID for
the domain to all DMA traffics out of the subset of this
device; and the IOMMU should translate the DMA requests
in PASID granularity.
This adds the intel_iommu_aux_attach/detach_device() ops
to support managing PASID granular translation structures
when the device driver has enabled multiple domains per
device.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This adds the iommu ops entries for aux-domain per-device
feature query and enable/disable.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This moves intel_iommu_enable_pasid() out of the scope of
CONFIG_INTEL_IOMMU_SVM with more and more features requiring
pasid function.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
VT-d Rev3.0 has made a few changes to the page request interface,
1. widened PRQ descriptor from 128 bits to 256 bits;
2. removed streaming response type;
3. introduced private data that requires page response even the
request is not last request in group (LPIG).
This is a supplement to commit 1c4f88b7f1 ("iommu/vt-d: Shared
virtual address in scalable mode") and makes the svm code compliant
with VT-d Rev3.0.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Fixes: 1c4f88b7f1 ("iommu/vt-d: Shared virtual address in scalable mode")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Deferred invalidation is an ECS specific feature. It will not be
supported when IOMMU works in scalable mode. As we deprecated the
ECS support, remove deferred invalidation and cleanup the code.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Cc: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This patch enables the current SVA (Shared Virtual Address)
implementation to work in the scalable mode.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This adds an interface to setup the PASID entries for first
level page table translation.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This patch enables the translation for requests without PASID in
the scalable mode by setting up the root and context entries.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This adds the interfaces to setup or tear down the structures
for second level page table translations. This includes types
of second level only translation and pass through.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Intel vt-d spec rev3.0 requires software to use 256-bit
descriptors in invalidation queue. As the spec reads in
section 6.5.2:
Remapping hardware supporting Scalable Mode Translations
(ECAP_REG.SMTS=1) allow software to additionally program
the width of the descriptors (128-bits or 256-bits) that
will be written into the Queue. Software should setup the
Invalidation Queue for 256-bit descriptors before progra-
mming remapping hardware for scalable-mode translation as
128-bit descriptors are treated as invalid descriptors
(see Table 21 in Section 6.5.2.10) in scalable-mode.
This patch adds 256-bit invalidation descriptor support
if the hardware presents scalable mode capability.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
So that they could also be used in other source files.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Cc: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The Intel vt-d spec rev3.0 introduces a new translation
mode called scalable mode, which enables PASID-granular
translations for first level, second level, nested and
pass-through modes. At the same time, the previous
Extended Context (ECS) mode is deprecated (no production
ever implements ECS).
This patch adds enumeration for Scalable Mode and removes
the deprecated ECS enumeration. It provides a boot time
option to disable scalable mode even hardware claims to
support it.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Commit e61d98d8da ("x64, x2apic/intr-remap: Intel vt-d, IOMMU
code reorganization") moved dma_remapping.h from drivers/pci/ to
current place. It is entirely VT-d specific, but uses a generic
name. This merges dma_remapping.h with include/linux/intel-iommu.h
and removes dma_remapping.h as the result.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Sohil Mehta <sohil.mehta@intel.com>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Liu, Yi L <yi.l.liu@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Add a new config option CONFIG_INTEL_IOMMU_DEBUGFS and do the base
enabling for Intel IOMMU debugfs.
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Co-Developed-by: Gayatri Kammela <gayatri.kammela@intel.com>
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Add new register definitions added in the VT-d 3.0 specification. Also
include registers that were missing previously.
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Gayatri Kammela <gayatri.kammela@intel.com>
Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
To reuse the static functions and the struct declarations, move them to
corresponding header files and export the needed functions.
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The obsolete per iommu pasid tables are no longer used. Hence,
clean up them.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This patch adds the interfaces for per PCI device pasid
table management. Currently we allocate one pasid table
for all PCI devices under the scope of an IOMMU. It's
insecure in some cases where multiple devices under one
single IOMMU unit support PASID features. With per PCI
device pasid table, we can achieve finer protection and
isolation granularity.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Suggested-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This adds a helper named for_each_device_domain() to iterate
over the elements in device_domain_list and invoke a callback
against each element. This allows to search the device_domain
list in other source files.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This allows the per device iommu data and some helpers to be
used in other files.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This patch applies the global pasid name space in the shared
virtual address (SVA) implementation.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
idr_for_each_entry() is used to iteratte over idr elements
of a given type. It isn't suitable for the globle pasid idr
since the pasid idr consumer could specify different types
of pointers to bind with a pasid.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This reverts commit ab96746aaa.
The commit ab96746aaa ("iommu/vt-d: Clean up pasid quirk for
pre-production devices") triggers ECS mode on some platforms
which have broken ECS support. As the result, graphic device
will be inoperable on boot.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107017
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
PFSID should be used in the invalidation descriptor for flushing
device IOTLBs on SRIOV VFs.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: stable@vger.kernel.org
Cc: "Ashok Raj" <ashok.raj@intel.com>
Cc: "Lu Baolu" <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
When SRIOV VF device IOTLB is invalidated, we need to provide
the PF source ID such that IOMMU hardware can gauge the depth
of invalidation queue which is shared among VFs. This is needed
when device invalidation throttle (DIT) capability is supported.
This patch adds bit definitions for checking and tracking PFSID.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: stable@vger.kernel.org
Cc: "Ashok Raj" <ashok.raj@intel.com>
Cc: "Lu Baolu" <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The pasid28 quirk is needed only for some pre-production devices.
Remove it to make the code concise.
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
So one could decode them without opening the specification.
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Add a check to verify IOMMU 5-level paging support. If the CPU supports
supports 5-level paging but the IOMMU does not support it then disable
SVM by not allocating PASID tables.
Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Add a check to verify IOMMU 1GB page support. If the CPU supports 1GB
pages but the IOMMU does not support it then disable SVM by not
allocating PASID tables.
Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Currently Page Request Overflow bit in IOMMU Fault Status register
is not cleared. Not clearing this bit would mean that any future
page-request is going to be automatically dropped by IOMMU.
Suggested-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There is already helper functions to do 64-bit I/O on 32-bit machines or
buses, thus we don't need to reinvent the wheel.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
There is currently support for iommu sysfs bindings, but
those need to be implemented in the IOMMU drivers. Add a
more generic version of this by adding a struct device to
struct iommu_device and use that for the sysfs bindings.
Also convert the AMD and Intel IOMMU driver to make use of
it.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This struct represents one hardware iommu in the iommu core
code. For now it only has the iommu-ops associated with it,
but that will be extended soon.
The register/unregister interface is also added, as well as
making use of it in the Intel and AMD IOMMU drivers.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Somehow I ended up with an off-by-three error in calculating the size of
the PASID and PASID State tables, which triggers allocations failures as
those tables unfortunately have to be physically contiguous.
In fact, even the *correct* maximum size of 8MiB is problematic and is
wont to lead to allocation failures. Since I have extracted a promise
that this *will* be fixed in hardware, I'm happy to limit it on the
current hardware to a maximum of 0x20000 PASIDs, which gives us 1MiB
tables — still not ideal, but better than before.
Reported by Mika Kuoppala <mika.kuoppala@linux.intel.com> and also by
Xunlei Pang <xlpang@redhat.com> who submitted a simpler patch to fix
only the allocation (and not the free) to the "correct" limit... which
was still problematic.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Cc: stable@vger.kernel.org
According to the VT-d specification we need to clear the PPR bit in
the Page Request Status register when handling page requests, or the
hardware won't generate any more interrupts.
This wasn't actually necessary on SKL/KBL (which may well be the
subject of a hardware erratum, although it's harmless enough). But
other implementations do appear to get it right, and we only ever get
one interrupt unless we clear the PPR bit.
Reported-by: CQ Tang <cq.tang@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@vger.kernel.org
This provides basic PASID support for endpoint devices, tested with a
version of the i915 driver.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>