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  1. 02 6月, 2020 2 次提交
  3. 18 5月, 2020 1 次提交
  5. 25 1月, 2020 1 次提交
  7. 24 9月, 2019 2 次提交
  9. 28 8月, 2019 3 次提交
  11. 22 12月, 2018 1 次提交
  13. 19 12月, 2018 1 次提交
  15. 30 7月, 2018 2 次提交
  17. 16 7月, 2018 1 次提交
  19. 12 7月, 2018 1 次提交
  21. 03 6月, 2018 1 次提交
  23. 13 4月, 2018 1 次提交
    • M
      powerpc/64s: Fix CPU_FTRS_ALWAYS vs DT CPU features · 81b654c2
      由 Michael Ellerman 提交于 
      The cpu_has_feature() mechanism has an optimisation where at build
time we construct a mask of the CPU feature bits that will always be
true for the given .config, based on the platform/bitness/etc. that we
are building for.

That is incompatible with DT CPU features, where the set of CPU
features is dependent on feature flags that are given to us by
firmware.

The result is that some feature bits can not be *disabled* by DT CPU
features. Or more accurately, they can be disabled but they will still
appear in the ALWAYS mask, meaning cpu_has_feature() will always
return true for them.

In the past this hasn't really been a problem because on Book3S
64 (where we support DT CPU features), the set of ALWAYS bits has been
very small. That was because we always built for POWER4 and later,
meaning the set of common bits was small.

The only bit that could be cleared by DT CPU features that was also in
the ALWAYS mask was CPU_FTR_NODSISRALIGN, and that was only used in
the alignment handler to create a fake DSISR. That code was itself
deleted in 31bfdb03 ("powerpc: Use instruction emulation
infrastructure to handle alignment faults") (Sep 2017).

However the set of ALWAYS features changed with the recent commit
db5ae1c1 ("powerpc/64s: Refine feature sets for little endian
builds") which restricted the set of feature flags when building
little endian to Power7 or later. That caused the ALWAYS mask to
become much larger for little endian builds.

The result is that the following feature bits can currently not
be *disabled* by DT CPU features:

  CPU_FTR_REAL_LE, CPU_FTR_MMCRA, CPU_FTR_CTRL, CPU_FTR_SMT,
  CPU_FTR_PURR, CPU_FTR_SPURR, CPU_FTR_DSCR, CPU_FTR_PKEY,
  CPU_FTR_VMX_COPY, CPU_FTR_CFAR, CPU_FTR_HAS_PPR.

To fix it we need to mask the set of ALWAYS features with the base set
of DT CPU features, ie. the features that are always enabled by DT CPU
features. That way there are no bits in the ALWAYS mask that are not
also always set by DT CPU features.

Fixes: db5ae1c1 ("powerpc/64s: Refine feature sets for little endian builds")
Reviewed-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      81b654c2
  25. 05 4月, 2018 1 次提交
  27. 01 4月, 2018 1 次提交
  29. 31 3月, 2018 4 次提交
  31. 27 3月, 2018 1 次提交
  33. 23 3月, 2018 5 次提交
    • P
      powerpc: Add CPU feature bits for TM bug workarounds on POWER9 v2.2 · b5af4f27
      由 Paul Mackerras 提交于 
      This adds a CPU feature bit which is set for POWER9 "Nimbus" DD2.2
processors which will be used to enable the hypervisor to assist
hardware with the handling of checkpointed register values while the
CPU is in suspend state, in order to work around hardware bugs.  The
hardware assistance for these workarounds introduced a new hardware
bug relating to the XER[SO] bit.  We add a separate feature bit for
this bug in case future chips fix it while still requiring the
hypervisor assistance with suspend state.

When the dt_cpu_ftrs subsystem is in use, the software assistance can
be enabled using a "tm-suspend-hypervisor-assist" node in the device
tree, and a "tm-suspend-xer-so-bug" node enables the workarounds for
the XER[SO] bug.  In the absence of such nodes, a quirk enables both
for POWER9 "Nimbus" DD2.2 processors.
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      b5af4f27
    • P
      powerpc: Free up CPU feature bits on 64-bit machines · 9bbf0b57
      由 Paul Mackerras 提交于 
      This moves all the CPU feature bits that are only used on 32-bit
machines to the top 20 bits of the CPU feature word and arranges
for them to be defined only in 32-bit builds.  The features that
are common to 32-bit and 64-bit machines are moved to bits 0-11
of the CPU feature word.  This means that for 64-bit platforms,
bits 44-63 can now be used for new features that only exist on
64-bit machines.  (These bit numbers are counting from the right,
i.e. the LSB is bit 0.)

Because CPU_FTR_L3_DISABLE_NAP moved from the low 16 bits to the high
16 bits, we have to adjust some assembly code.  Also, CPU_FTR_EMB_HV
moved from the high 16 bits to the low 16 bits.

Note that CPU_FTR_REAL_LE only applies to 64-bit chips, because only
64-bit chips (POWER6, 7, 8, 9) have a true little-endian mode that is
a CPU execution mode as opposed to being a page attribute.

With this we now have 20 free CPU feature bits on 64-bit machines.
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      9bbf0b57
    • P
      powerpc: Book E: Remove unused CPU_FTR_L2CSR bit · dd0efb3f
      由 Paul Mackerras 提交于 
      The CPU_FTR_L2CSR bit is never tested anywhere, so let's reclaim the
bit.

The last usage was removed in 86d63363 ("powerpc/e500mc: Remove
dead L2 flushing code in idle_e500.S") (Jun 2015).
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      dd0efb3f
    • P
      powerpc: Use feature bit for RTC presence rather than timebase presence · c0d64cf9
      由 Paul Mackerras 提交于 
      All PowerPC CPUs other than the original PPC601 have a timebase
register rather than the "real-time clock" (RTC) register that the
PPC601 (and the original POWER and POWER2 CPUs) had.  Currently
we have a CPU feature bit to indicate the presence of the timebase,
but it makes more sense to use a bit to indicate the unusual
situation rather than the common situation.  This therefore defines
a CPU_FTR_USE_RTC bit in place of the CPU_FTR_USE_TB bit, and
arranges for it to be set on PPC601 systems.
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      c0d64cf9
    • A
      powerpc/mm: Fixup tlbie vs store ordering issue on POWER9 · a5d4b589
      由 Aneesh Kumar K.V 提交于 
      On POWER9, under some circumstances, a broadcast TLB invalidation
might complete before all previous stores have drained, potentially
allowing stale stores from becoming visible after the invalidation.
This works around it by doubling up those TLB invalidations which was
verified by HW to be sufficient to close the risk window.

This will be documented in a yet-to-be-published errata.

Fixes: 1a472c9d ("powerpc/mm/radix: Add tlbflush routines")
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Enable the feature in the DT CPU features code for all Power9,
      rename the feature to CPU_FTR_P9_TLBIE_BUG per benh.]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      a5d4b589
  35. 20 1月, 2018 1 次提交
    • R
      powerpc: Enable pkey subsystem · cf43d3b2
      由 Ram Pai 提交于 
      PAPR defines 'ibm,processor-storage-keys' property. It exports two
values. The first value holds the number of data-access keys and the
second holds the number of instruction-access keys. Due to a bug in
the firmware, instruction-access keys is always reported as zero.
However any key can be configured to disable data-access and/or
disable execution-access. The inavailablity of the second value is not
a big handicap, though it could have been used to determine if the
platform supported disable-execution-access.

Non-PAPR platforms do not define this property in the device tree yet.
Fortunately power8 is the only released Non-PAPR platform that is
supported. Here, we hardcode the number of supported pkey to 32, by
consulting the PowerISA3.0

This patch calculates the number of keys supported by the platform.
Also it determines the platform support for read/write/execution
access support for pkeys.
Signed-off-by: NRam Pai <linuxram@us.ibm.com>
[mpe: Use a PVR check instead of CPU_FTR for execute. Restrict to
 Power7/8/9 for now until older CPUs are tested.]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      cf43d3b2
  37. 17 1月, 2018 1 次提交
    • N
      powerpc/64s: Improve local TLB flush for boot and MCE on POWER9 · d4748276
      由 Nicholas Piggin 提交于 
      There are several cases outside the normal address space management
where a CPU's entire local TLB is to be flushed:

  1. Booting the kernel, in case something has left stale entries in
     the TLB (e.g., kexec).

  2. Machine check, to clean corrupted TLB entries.

One other place where the TLB is flushed, is waking from deep idle
states. The flush is a side-effect of calling ->cpu_restore with the
intention of re-setting various SPRs. The flush itself is unnecessary
because in the first case, the TLB should not acquire new corrupted
TLB entries as part of sleep/wake (though they may be lost).

This type of TLB flush is coded inflexibly, several times for each CPU
type, and they have a number of problems with ISA v3.0B:

- The current radix mode of the MMU is not taken into account, it is
  always done as a hash flushn For IS=2 (LPID-matching flush from host)
  and IS=3 with HV=0 (guest kernel flush), tlbie(l) is undefined if
  the R field does not match the current radix mode.

- ISA v3.0B hash must flush the partition and process table caches as
  well.

- ISA v3.0B radix must flush partition and process scoped translations,
  partition and process table caches, and also the page walk cache.

So consolidate the flushing code and implement it in C and inline asm
under the mm/ directory with the rest of the flush code. Add ISA v3.0B
cases for radix and hash, and use the radix flush in radix environment.

Provide a way for IS=2 (LPID flush) to specify the radix mode of the
partition. Have KVM pass in the radix mode of the guest.

Take out the flushes from early cputable/dt_cpu_ftrs detection hooks,
and move it later in the boot process after, the MMU registers are set
up and before relocation is first turned on.

The TLB flush is no longer called when restoring from deep idle states.
This was not be done as a separate step because booting secondaries
uses the same cpu_restore as idle restore, which needs the TLB flush.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      d4748276
  39. 15 11月, 2017 1 次提交
    • M
      powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 feature · 3ffa9d9e
      由 Michael Ellerman 提交于 
      Recently we added a CPU feature for Power9 DD2.0, to capture the fact
that some workarounds are required only on Power9 DD1 and DD2.0 but
not DD2.1 or later.

Then in commit 9d2f510a ("powerpc/64s/idle: avoid POWER9 DD1 and
DD2.0 ERAT workaround on DD2.1") and commit e3646330
"powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 PMU workaround on
DD2.1") we changed CPU_FTR_SECTIONs to check for DD1 or DD20, eg:

  BEGIN_FTR_SECTION
          PPC_INVALIDATE_ERAT
  END_FTR_SECTION_IFSET(CPU_FTR_POWER9_DD1 | CPU_FTR_POWER9_DD20)

Unfortunately although this reads as "if set DD1 or DD2.0", the or is
a bitwise or and actually generates a mask of both bits. The code that
does the feature patching then checks that the value of the CPU
features masked with that mask are equal to the mask.

So the end result is we're checking for DD1 and DD20 being set, which
never happens. Yes the API is terrible.

Removing the ERAT workaround on DD2.0 results in random SEGVs, the
system tends to boot, but things randomly die including sometimes
dhclient, udev etc.

To fix the problem and hopefully avoid it in future, we remove the
DD2.0 CPU feature and instead add a DD2.1 (or later) feature. This
allows us to easily express that the workarounds are required if DD2.1
is not set.

At some point we will drop the DD1 workarounds entirely and some of
this can be cleaned up.

Fixes: 9d2f510a ("powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 ERAT workaround on DD2.1")
Fixes: e3646330 ("powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 PMU workaround on DD2.1")
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      3ffa9d9e
  41. 06 11月, 2017 2 次提交
  43. 02 11月, 2017 1 次提交
    • G
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      由 Greg Kroah-Hartman 提交于 
      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: NKate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: NPhilippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  45. 10 8月, 2017 1 次提交
  47. 01 6月, 2017 1 次提交
    • M
      powerpc/64: Reclaim CPU_FTR_SUBCORE · 0e5e7f5e
      由 Michael Ellerman 提交于 
      We are running low on CPU feature bits, so we only want to use them when
it's really necessary.

CPU_FTR_SUBCORE is only used in one place, and only in C, so we don't
need it in order to make asm patching work. It can only be set on
"Power8" CPUs, which in practice means POWER8, POWER8E and POWER8NVL.
There are no plans to implement it on future CPUs, but if there ever
were we could retrofit it then.

Although KVM uses subcores, it never looks at the CPU feature, it either
looks at the ISA level or the threads_per_subcore value.

So drop the CPU feature and do a PVR check instead. Drop the device tree
"subcore" feature as we no longer support doing anything with it, and we
will drop it from skiboot too.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      0e5e7f5e
  49. 09 5月, 2017 1 次提交
  51. 19 4月, 2017 2 次提交