Commit Graph

21 Commits

Author SHA1 Message Date
Thierry Reding
02b0cc52c0 memory: tegra: Add Tegra186 support
The memory controller found on Tegra186 is different in some respects to
its predecessors. Most notably it no longer implements an SMMU, but does
assign ARM SMMU stream IDs for each memory client instead.

Provide a driver that programs these registers so that memory clients
can translate addresses via the ARM SMMU.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2017-12-13 12:58:21 +01:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Christophe Jaillet
b92f4380a1 memory: tegra: Add a missing 'of_node_put()' call
If 'of_find_device_by_node()' fails, an 'of_node_put()' call is missing in
the error handling path.
Fix it by reordering the code.

While at it, remove some empty lines in a more or less similar construction
a few lines below.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2017-01-25 07:57:13 +01:00
Amitoj Kaur Chawla
55bb1d8355 memory: tegra: mc: Add missing of_node_put()
for_each_child_of_node() performs an of_node_get() on each iteration, so
to break out of the loop an of_node_put() is required.

Found using Coccinelle. The semantic patch used for this is as follows:

// <smpl>
@@
expression e;
local idexpression n;
@@

 for_each_child_of_node(..., n) {
   ... when != of_node_put(n)
       when != e = n
(
   return n;
|
+  of_node_put(n);
?  return ...;
)
   ...
 }
// </smpl>

Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2016-06-14 11:39:39 +02:00
Julia Lawall
d1122e4b76 memory: tegra: Delete unneeded of_node_put()
for_each_child_of_node() performs an of_node_put() on each iteration, so
putting an of_node_put() before a continue results in a double put.

The semantic match that finds this problem is as follows
(http://coccinelle.lip6.fr):

// <smpl>
@@
expression root,e;
local idexpression child;
iterator name for_each_child_of_node;
@@

 for_each_child_of_node(root, child) {
   ... when != of_node_get(child)
*  of_node_put(child);
   ...
*  continue;
}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2016-06-14 11:39:39 +02:00
Amitoj Kaur Chawla
aafb197f75 memory: tegra: tegra124-emc: Add missing of_node_put()
for_each_child_of_node() performs an of_node_get() on each iteration, so
to break out of the loop an of_node_put() is required.

Found using Coccinelle. The semantic patch used for this is as follows:

// <smpl>
@@
expression e;
local idexpression n;
@@

 for_each_child_of_node(..., n) {
   ... when != of_node_put(n)
       when != e = n
(
   return n;
|
+  of_node_put(n);
?  return ...;
)
   ...
 }
// </smpl>

Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2016-06-14 11:39:38 +02:00
Vince Hsu
e2127ae7a5 memory/tegra: Add number of TLB lines for Tegra124
Tegra124 was accidentally left out when the number of TLB lines was
parameterized in commit 11cec15bf3 ("iommu/tegra-smmu: Parameterize
number of TLB lines"). Fortunately this doesn't cause any noticeable
regressions upstream, presumably because there aren't any use-cases
that exercise enough pressure on the SMMU. But it is a regression
nonetheless, so let's fix it.

Fixes: 11cec15bf3 ("iommu/tegra-smmu: Parameterize number of TLB lines")
Signed-off-by: Vince Hsu <vince.h@nvidia.com>
Signed-off-by: Tomasz Figa <tfiga@chromium.org>
[treding@nvidia.com: extract from unrelated patch]
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-12-14 16:11:35 +01:00
Linus Torvalds
9a9952bbd7 IOMMU Updates for Linux v4.3
This time the IOMMU updates are mostly cleanups or fixes. No big new
 features or drivers this time. In particular the changes include:
 
 	* Bigger cleanup of the Domain<->IOMMU data structures and the
 	  code that manages them in the Intel VT-d driver. This makes
 	  the code easier to understand and maintain, and also easier to
 	  keep the data structures in sync. It is also a preparation
 	  step to make use of default domains from the IOMMU core in the
 	  Intel VT-d driver.
 
 	* Fixes for a couple of DMA-API misuses in ARM IOMMU drivers,
 	  namely in the ARM and Tegra SMMU drivers.
 
 	* Fix for a potential buffer overflow in the OMAP iommu driver's
 	  debug code
 
 	* A couple of smaller fixes and cleanups in various drivers
 
 	* One small new feature: Report domain-id usage in the Intel
 	  VT-d driver to easier detect bugs where these are leaked.
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Merge tag 'iommu-updates-v4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu updates for from Joerg Roedel:
 "This time the IOMMU updates are mostly cleanups or fixes.  No big new
  features or drivers this time.  In particular the changes include:

   - Bigger cleanup of the Domain<->IOMMU data structures and the code
     that manages them in the Intel VT-d driver.  This makes the code
     easier to understand and maintain, and also easier to keep the data
     structures in sync.  It is also a preparation step to make use of
     default domains from the IOMMU core in the Intel VT-d driver.

   - Fixes for a couple of DMA-API misuses in ARM IOMMU drivers, namely
     in the ARM and Tegra SMMU drivers.

   - Fix for a potential buffer overflow in the OMAP iommu driver's
     debug code

   - A couple of smaller fixes and cleanups in various drivers

   - One small new feature: Report domain-id usage in the Intel VT-d
     driver to easier detect bugs where these are leaked"

* tag 'iommu-updates-v4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (83 commits)
  iommu/vt-d: Really use upper context table when necessary
  x86/vt-d: Fix documentation of DRHD
  iommu/fsl: Really fix init section(s) content
  iommu/io-pgtable-arm: Unmap and free table when overwriting with block
  iommu/io-pgtable-arm: Move init-fn declarations to io-pgtable.h
  iommu/msm: Use BUG_ON instead of if () BUG()
  iommu/vt-d: Access iomem correctly
  iommu/vt-d: Make two functions static
  iommu/vt-d: Use BUG_ON instead of if () BUG()
  iommu/vt-d: Return false instead of 0 in irq_remapping_cap()
  iommu/amd: Use BUG_ON instead of if () BUG()
  iommu/amd: Make a symbol static
  iommu/amd: Simplify allocation in irq_remapping_alloc()
  iommu/tegra-smmu: Parameterize number of TLB lines
  iommu/tegra-smmu: Factor out tegra_smmu_set_pde()
  iommu/tegra-smmu: Extract tegra_smmu_pte_get_use()
  iommu/tegra-smmu: Use __GFP_ZERO to allocate zeroed pages
  iommu/tegra-smmu: Remove PageReserved manipulation
  iommu/tegra-smmu: Convert to use DMA API
  iommu/tegra-smmu: smmu_flush_ptc() wants device addresses
  ...
2015-09-08 17:22:35 -07:00
Thierry Reding
11cec15bf3 iommu/tegra-smmu: Parameterize number of TLB lines
The number of TLB lines was increased from 16 on Tegra30 to 32 on
Tegra114 and later. Parameterize the value so that the initial default
can be set accordingly.

On Tegra30, initializing the value to 32 would effectively disable the
TLB and hence cause massive latencies for memory accesses translated
through the SMMU. This is especially noticeable for isochronuous clients
such as display, whose FIFOs would continuously underrun.

Fixes: 8918465163 ("memory: Add NVIDIA Tegra memory controller support")
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-08-13 17:05:28 +02:00
Thierry Reding
588c43a7bd memory: tegra: Add Tegra210 support
Add the table of memory clients and SWGROUPs for Tegra210 to enable SMMU
support for this new SoC.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-08-13 16:07:52 +02:00
Paul Walmsley
3c01cf3bef memory: tegra: Add support for a variable-size client ID bitfield
Recent versions of the Tegra MC hardware extend the size of the client
ID bitfield in the MC_ERR_STATUS register by one bit.  While one could
simply extend the bitfield for older hardware, that would allow data
from reserved bits into the driver code, which is generally a bad idea
on principle.  So this patch instead passes in the client ID mask from
from the per-SoC MC data.

There's no MC support for T210 (yet), but when that support winds up
in the kernel, the appropriate soc->client_id_mask value for that chip
will be 0xff.

Based on an original patch by David Ung <davidu@nvidia.com>.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Paul Walmsley <pwalmsley@nvidia.com>
Cc: Thierry Reding <treding@nvidia.com>
Cc: David Ung <davidu@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-08-13 16:07:52 +02:00
Russell King
4b3c7d1076 iommu/tegra-smmu: Move flush_dcache to tegra-smmu.c
Drivers should not be using __cpuc_* functions nor outer_cache_flush()
directly.  This change partly cleans up tegra-smmu.c.

The only difference between cache handling of the tegra variants is
Denver, which omits the call to outer_cache_flush().  This is due to
Denver being an ARM64 CPU, and the ARM64 architecture does not provide
this function.  (This, in itself, is a good reason why these should not
be used.)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[treding@nvidia.com: fix build failure on 64-bit ARM]
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-08-13 16:06:40 +02:00
Thierry Reding
30a636f984 memory: tegra: Expose supported rates via debugfs
In order to ease testing, expose the list of supported EMC frequencies
via debugfs.

Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-07-16 09:51:47 +02:00
Arnd Bergmann
44fb3026ad ARM: tegra: Add EMC driver for v4.2-rc1
This introduces the EMC driver that's required to scale the external
 memory frequency.
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Merge tag 'tegra-for-4.2-emc' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into next/drivers

Merge "ARM: tegra: Add EMC driver for v4.2-rc1" from Thierry Reding:

This introduces the EMC driver that's required to scale the external
memory frequency.

* tag 'tegra-for-4.2-emc' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux:
  memory: tegra: Add EMC frequency debugfs entry
  memory: tegra: Add EMC (external memory controller) driver
  memory: tegra: Add API needed by the EMC driver
  of: Add Tegra124 EMC bindings
  of: Document timings subnode of nvidia,tegra-mc
2015-05-13 17:59:35 +02:00
Mikko Perttunen
9c77a81f21 memory: tegra: Add EMC frequency debugfs entry
This file in debugfs can be used to get or set the EMC frequency.
Reading the file will return the currently set frequency in Hz, while
writing the file sets the specified frequency rounded to the next
highest frequency supported by the board.

Will be very useful when tuning memory scaling.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
[treding@nvidia.com: add "emc" debugfs directory]
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-05-05 11:39:48 +02:00
Mikko Perttunen
73a7f0a906 memory: tegra: Add EMC (external memory controller) driver
Implements functionality needed to change the rate of the memory bus
clock.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-05-05 11:12:17 +02:00
Mikko Perttunen
3d9dd6fdd2 memory: tegra: Add API needed by the EMC driver
The EMC driver needs to know the number of external memory devices and
also needs to update the EMEM configuration based on the new rate of the
memory bus.

To know how to update the EMEM config, looks up the values of the burst
regs in the DT, for a given timing.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-05-05 11:10:19 +02:00
Tomeu Vizoso
6f0a4d0c26 memory: tegra: Disable ARBITRATION_EMEM interrupt
As this interrupt is just for development purposes, as the TRM says, and
the sheer amount of interrupts fired can seriously disrupt userspace
when testing the lower frequencies supported by the EMC.

From the TRM:

"There is one performance warning type interrupt: ARBITRATION_EMEM. It
fires when the MC detects that a request has been pending in the Row
Sorter long enough to hit the DEADLOCK_PREVENTION_SLACK_THRESHOLD. In
addition to true performance problems, this interrupt may fire in
situations such as clock-change where the EMC backpressures pending
traffic for long periods of time. This interrupt helps developers
identify and debug performance issues and configuration issues."

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-05-04 15:09:36 +02:00
Thierry Reding
242b1d7133 memory: tegra: Add Tegra132 support
The memory controller on Tegra132 is very similar to the one found on
Tegra124. But the Denver CPUs don't have an outer cache, so dcache
maintenance is done slightly differently.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-05-04 12:54:23 +02:00
Thierry Reding
e660df07ab memory: tegra: Add SWGROUP names
Subsequent patches will add debugfs files that print the status of the
SWGROUPs. Add a new names field and complement the SoC tables with the
names of the individual SWGROUPs.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-05-04 12:54:23 +02:00
Thierry Reding
8918465163 memory: Add NVIDIA Tegra memory controller support
The memory controller on NVIDIA Tegra exposes various knobs that can be
used to tune the behaviour of the clients attached to it.

Currently this driver sets up the latency allowance registers to the HW
defaults. Eventually an API should be exported by this driver (via a
custom API or a generic subsystem) to allow clients to register latency
requirements.

This driver also registers an IOMMU (SMMU) that's implemented by the
memory controller. It is supported on Tegra30, Tegra114 and Tegra124
currently. Tegra20 has a GART instead.

The Tegra SMMU operates on memory clients and SWGROUPs. A memory client
is a unidirectional, special-purpose DMA master. A SWGROUP represents a
set of memory clients that form a logical functional unit corresponding
to a single device. Typically a device has two clients: one client for
read transactions and one client for write transactions, but there are
also devices that have only read clients, but many of them (such as the
display controllers).

Because there is no 1:1 relationship between memory clients and devices
the driver keeps a table of memory clients and the SWGROUPs that they
belong to per SoC. Note that this is an exception and due to the fact
that the SMMU is tightly integrated with the rest of the Tegra SoC. The
use of these tables is discouraged in drivers for generic IOMMU devices
such as the ARM SMMU because the same IOMMU could be used in any number
of SoCs and keeping such tables for each SoC would not scale.

Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-12-04 16:11:47 +01:00