The Arm SMMU drivers are getting fat on vendor value-add, so move them
to their own subdirectory out of the way of the other IOMMU drivers.

Suggested-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Will Deacon <will@kernel.org>

Add global/context fault hooks to allow vendor specific implementations
override default fault interrupt handlers.

Update NVIDIA implementation to override the default global/context fault
interrupt handlers and handle interrupts across the two ARM MMU-500s that
are programmed identically.

Signed-off-by: Krishna Reddy <vdumpa@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Pritesh Raithatha <praithatha@nvidia.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Thierry Reding <thierry.reding@gmail.com>
Link: https://lore.kernel.org/r/20200718193457.30046-6-vdumpa@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>

NVIDIA's Tegra194 SoC has three ARM MMU-500 instances.
It uses two of the ARM MMU-500s together to interleave IOVA
accesses across them and must be programmed identically.
This implementation supports programming the two ARM MMU-500s
that must be programmed identically.

The third ARM MMU-500 instance is supported by standard
arm-smmu.c driver itself.

Signed-off-by: Krishna Reddy <vdumpa@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Pritesh Raithatha <praithatha@nvidia.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Thierry Reding <thierry.reding@gmail.com>
Link: https://lore.kernel.org/r/20200718193457.30046-4-vdumpa@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>

Move TLB timeout and spin count macros to header file to
allow using the same from vendor specific implementations.

Signed-off-by: Krishna Reddy <vdumpa@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Pritesh Raithatha <praithatha@nvidia.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Thierry Reding <thierry.reding@gmail.com>
Link: https://lore.kernel.org/r/20200718193457.30046-2-vdumpa@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>

Implement the new def_domain_type call-back for the ARM
SMMU driver. We need this to support requesting the domain
type by the client devices.

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/28c5d101cc4ac29aff3553ecec7cf256d0907ed7.1587407458.git.saiprakash.ranjan@codeaurora.org
Signed-off-by: Will Deacon <will@kernel.org>

Commit 05a648cd2dd7 ("iommu/io-pgtable-arm: Rationalise TCR handling")
reworked the way in which the TCR register value is returned from the
io-pgtable code when targetting the Arm long-descriptor format, in
preparation for allowing page-tables to target TTBR1.

As it turns out, the new interface is a lot nicer to use, so do the same
conversion for the VTCR register even though there is only a single base
register for stage-2 translation.

Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

Now that we have arm-smmu.h defining various SMMU constants, ensure that
they are namespaced with the ARM_SMMU_ prefix in order to avoid conflicts
with the CPU, such as the one we're currently bodging around with the
TCR.

Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

Although it's conceptually nice for the io_pgtable_cfg to provide a
standard VMSA TCR value, the reality is that no VMSA-compliant IOMMU
looks exactly like an Arm CPU, and they all have various other TCR
controls which io-pgtable can't be expected to understand. Thus since
there is an expectation that drivers will have to add to the given TCR
value anyway, let's strip it down to just the essentials that are
directly relevant to io-pgtable's inner workings - namely the various
sizes and the walk attributes.

Tested-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[will: Add missing include of bitfield.h]
Signed-off-by: Will Deacon <will@kernel.org>

Add reset hook for sdm845 based platforms to turn off
the wait-for-safe sequence.

Understanding how wait-for-safe logic affects USB and UFS performance
on MTP845 and DB845 boards:

Qcom's implementation of arm,mmu-500 adds a WAIT-FOR-SAFE logic
to address under-performance issues in real-time clients, such as
Display, and Camera.
On receiving an invalidation requests, the SMMU forwards SAFE request
to these clients and waits for SAFE ack signal from real-time clients.
The SAFE signal from such clients is used to qualify the start of
invalidation.
This logic is controlled by chicken bits, one for each - MDP (display),
IFE0, and IFE1 (camera), that can be accessed only from secure software
on sdm845.

This configuration, however, degrades the performance of non-real time
clients, such as USB, and UFS etc. This happens because, with wait-for-safe
logic enabled the hardware tries to throttle non-real time clients while
waiting for SAFE ack signals from real-time clients.

On mtp845 and db845 devices, with wait-for-safe logic enabled by the
bootloaders we see degraded performance of USB and UFS when kernel
enables the smmu stage-1 translations for these clients.
Turn off this wait-for-safe logic from the kernel gets us back the perf
of USB and UFS devices until we re-visit this when we start seeing perf
issues on display/camera on upstream supported SDM845 platforms.
The bootloaders on these boards implement secure monitor callbacks to
handle a specific command - QCOM_SCM_SVC_SMMU_PROGRAM with which the
logic can be toggled.

There are other boards such as cheza whose bootloaders don't enable this
logic. Such boards don't implement callbacks to handle the specific SCM
call so disabling this logic for such boards will be a no-op.

This change is inspired by the downstream change from Patrick Daly
to address performance issues with display and camera by handling
this wait-for-safe within separte io-pagetable ops to do TLB
maintenance. So a big thanks to him for the change and for all the
offline discussions.

Without this change the UFS reads are pretty slow:
$ time dd if=/dev/sda of=/dev/zero bs=1048576 count=10 conv=sync
10+0 records in
10+0 records out
10485760 bytes (10.0MB) copied, 22.394903 seconds, 457.2KB/s
real    0m 22.39s
user    0m 0.00s
sys     0m 0.01s

With this change they are back to rock!
$ time dd if=/dev/sda of=/dev/zero bs=1048576 count=300 conv=sync
300+0 records in
300+0 records out
314572800 bytes (300.0MB) copied, 1.030541 seconds, 291.1MB/s
real    0m 1.03s
user    0m 0.00s
sys     0m 0.54s

Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Signed-off-by: Will Deacon <will@kernel.org>

Although CONFIG_ARM_SMMU_DISABLE_BYPASS_BY_DEFAULT is a welcome tool
for smoking out inadequate firmware, the failure mode is non-obvious
and can be confusing for end users. Add some special-case reporting of
Unidentified Stream Faults to help clarify this particular symptom.
Since we're adding yet another print to the mix, also break out an
explicit ratelimit state to make sure everything stays together (and
reduce the static storage footprint a little).

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>