Commit Graph

11105 Commits

Author SHA1 Message Date
Paul Burton
ae4cd0b1a4
MIPS: barrier: Make __smp_mb__before_atomic() a no-op for Loongson3
Loongson3 systems with CONFIG_CPU_LOONGSON3_WORKAROUNDS enabled already
emit a full completion barrier as part of the inline assembly containing
LL/SC loops for atomic operations. As such the barrier emitted by
__smp_mb__before_atomic() is redundant, and we can remove it.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:43:08 -07:00
Paul Burton
7f56b12354
MIPS: barrier: Remove loongson_llsc_mb()
The loongson_llsc_mb() macro is no longer used - instead barriers are
emitted as part of inline asm using the __SYNC() macro. Remove the
now-defunct loongson_llsc_mb() macro.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:43:06 -07:00
Paul Burton
e84957e6ae
MIPS: syscall: Emit Loongson3 sync workarounds within asm
Generate the sync instructions required to workaround Loongson3 LL/SC
errata within inline asm blocks, which feels a little safer than doing
it from C where strictly speaking the compiler would be well within its
rights to insert a memory access between the separate asm statements we
previously had, containing sync & ll instructions respectively.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:43:05 -07:00
Paul Burton
3c1d3f0979
MIPS: futex: Emit Loongson3 sync workarounds within asm
Generate the sync instructions required to workaround Loongson3 LL/SC
errata within inline asm blocks, which feels a little safer than doing
it from C where strictly speaking the compiler would be well within its
rights to insert a memory access between the separate asm statements we
previously had, containing sync & ll instructions respectively.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:43:03 -07:00
Paul Burton
a91f2a1dba
MIPS: cmpxchg: Omit redundant barriers for Loongson3
When building a kernel configured to support Loongson3 LL/SC workarounds
(ie. CONFIG_CPU_LOONGSON3_WORKAROUNDS=y) the inline assembly in
__xchg_asm() & __cmpxchg_asm() already emits completion barriers, and as
such we don't need to emit extra barriers from the xchg() or cmpxchg()
macros. Add compile-time constant checks causing us to omit the
redundant memory barriers.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:43:01 -07:00
Paul Burton
6a57d2d1e7
MIPS: cmpxchg: Emit Loongson3 sync workarounds within asm
Generate the sync instructions required to workaround Loongson3 LL/SC
errata within inline asm blocks, which feels a little safer than doing
it from C where strictly speaking the compiler would be well within its
rights to insert a memory access between the separate asm statements we
previously had, containing sync & ll instructions respectively.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:43:00 -07:00
Paul Burton
9026737703
MIPS: bitops: Use smp_mb__before_atomic in test_* ops
Use smp_mb__before_atomic() rather than smp_mb__before_llsc() in
test_and_set_bit(), test_and_clear_bit() & test_and_change_bit(). The
_atomic() versions make semantic sense in these cases, and will allow a
later patch to omit redundant barriers for Loongson3 systems that
already include a barrier within __test_bit_op().

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:58 -07:00
Paul Burton
5bb29275df
MIPS: bitops: Emit Loongson3 sync workarounds within asm
Generate the sync instructions required to workaround Loongson3 LL/SC
errata within inline asm blocks, which feels a little safer than doing
it from C where strictly speaking the compiler would be well within its
rights to insert a memory access between the separate asm statements we
previously had, containing sync & ll instructions respectively.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:57 -07:00
Paul Burton
c042be02d7
MIPS: bitops: Use BIT_WORD() & BITS_PER_LONG
Rather than using custom SZLONG_LOG & SZLONG_MASK macros to shift & mask
a bit index to form word & bit offsets respectively, make use of the
standard BIT_WORD() & BITS_PER_LONG macros for the same purpose.

volatile is added to the definition of pointers to the long-sized word
we'll operate on, in order to prevent the compiler complaining that we
cast away the volatile qualifier of the addr argument. This should have
no effect on generated code, which in the LL/SC case is inline asm
anyway & in the non-LLSC case access is constrained by compiler barriers
provided by raw_local_irq_{save,restore}().

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:55 -07:00
Paul Burton
cc99987c37
MIPS: bitops: Abstract LL/SC loops
Introduce __bit_op() & __test_bit_op() macros which abstract away the
implementation of LL/SC loops. This cuts down on a lot of duplicate
boilerplate code, and also allows R10000_LLSC_WAR to be handled outside
of the individual bitop functions.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:53 -07:00
Paul Burton
aad028cadb
MIPS: bitops: Avoid redundant zero-comparison for non-LLSC
The IRQ-disabling non-LLSC fallbacks for bitops on UP systems already
return a zero or one, so there's no need to perform another comparison
against zero. Move these comparisons into the LLSC paths to avoid the
redundant work.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:52 -07:00
Paul Burton
d6103510e7
MIPS: bitops: Use the BIT() macro
Use the BIT() macro in asm/bitops.h rather than open-coding its
equivalent.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:50 -07:00
Paul Burton
a2e66b862c
MIPS: bitops: Allow immediates in test_and_{set,clear,change}_bit
The logical operations or & xor used in the test_and_set_bit_lock(),
test_and_clear_bit() & test_and_change_bit() functions currently force
the value 1<<bit to be placed in a register. If the bit is compile-time
constant & fits within the immediate field of an or/xor instruction (ie.
16 bits) then we can make use of the ori/xori instruction variants &
avoid the use of an extra register. Add the extra "i" constraints in
order to allow use of these immediate encodings.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:49 -07:00
Paul Burton
6bbe043bd3
MIPS: bitops: Implement test_and_set_bit() in terms of _lock variant
The only difference between test_and_set_bit() & test_and_set_bit_lock()
is memory ordering barrier semantics - the former provides a full
barrier whilst the latter only provides acquire semantics.

We can therefore implement test_and_set_bit() in terms of
test_and_set_bit_lock() with the addition of the extra memory barrier.
Do this in order to avoid duplicating logic.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:47 -07:00
Paul Burton
27aab27259
MIPS: bitops: ins start position is always an immediate
The start position for an ins instruction is always encoded as an
immediate, so allowing registers to be used by the inline asm makes no
sense. It should never happen anyway since a bit index should always be
small enough to be treated as an immediate, but remove the nonsensical
"r" for sanity.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:42 -07:00
Paul Burton
59361e9975
MIPS: bitops: Use MIPS_ISA_REV, not #ifdefs
Rather than #ifdef on CONFIG_CPU_* to determine whether the ins
instruction is supported we can simply check MIPS_ISA_REV to discover
whether we're targeting MIPSr2 or higher. Do so in order to clean up the
code.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:41 -07:00
Paul Burton
3d2920cf4f
MIPS: bitops: Only use ins for bit 16 or higher
set_bit() can set bits 0-15 using an ori instruction, rather than
loading the value -1 into a register & then using an ins instruction.

That is, rather than the following:

  li   t0, -1
  ll   t1, 0(t2)
  ins  t1, t0, 4, 1
  sc   t1, 0(t2)

We can have the simpler:

  ll   t1, 0(t2)
  ori  t1, t1, 0x10
  sc   t1, 0(t2)

The or path already allows immediates to be used, so simply restricting
the ins path to bits that don't fit in immediates is sufficient to take
advantage of this.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:39 -07:00
Paul Burton
fe7cd97e68
MIPS: bitops: Handle !kernel_uses_llsc first
Reorder conditions in our various bitops functions that check
kernel_uses_llsc such that they handle the !kernel_uses_llsc case first.
This allows us to avoid the need to duplicate the kernel_uses_llsc check
in all the other cases. For functions that don't involve barriers common
to the various implementations, we switch to returning from within each
if block making each case easier to read in isolation.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:37 -07:00
Paul Burton
1da7bce859
MIPS: atomic: Deduplicate 32b & 64b read, set, xchg, cmpxchg
Remove the remaining duplication between 32b & 64b in asm/atomic.h by
making use of an ATOMIC_OPS() macro to generate:

  - atomic_read()/atomic64_read()
  - atomic_set()/atomic64_set()
  - atomic_cmpxchg()/atomic64_cmpxchg()
  - atomic_xchg()/atomic64_xchg()

This is consistent with the way all other functions in asm/atomic.h are
generated, and ensures consistency between the 32b & 64b functions.

Of note is that this results in the above now being static inline
functions rather than macros.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:36 -07:00
Paul Burton
40e784b4d4
MIPS: atomic: Unify 32b & 64b sub_if_positive
Unify the definitions of atomic_sub_if_positive() &
atomic64_sub_if_positive() using a macro like we do for most other
atomic functions. This allows us to share the implementation ensuring
consistency between the two. Notably this provides the appropriate
loongson3_war barriers in the atomic64_sub_if_positive() case which were
previously missing.

The code is rearranged a little to handle the !kernel_uses_llsc case
first in order to de-indent the LL/SC case & allow us not to go over 80
characters per line.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:34 -07:00
Paul Burton
77d281b796
MIPS: atomic: Use _atomic barriers in atomic_sub_if_positive()
Use smp_mb__before_atomic() & smp_mb__after_atomic() in
atomic_sub_if_positive() rather than the equivalent
smp_mb__before_llsc() & smp_llsc_mb(). The former are more standard &
this preps us for avoiding redundant duplicate barriers on Loongson3 in
a later patch.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:32 -07:00
Paul Burton
4d1dbfe6cb
MIPS: atomic: Emit Loongson3 sync workarounds within asm
Generate the sync instructions required to workaround Loongson3 LL/SC
errata within inline asm blocks, which feels a little safer than doing
it from C where strictly speaking the compiler would be well within its
rights to insert a memory access between the separate asm statements we
previously had, containing sync & ll instructions respectively.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:31 -07:00
Paul Burton
a38ee6bb14
MIPS: atomic: Use one macro to generate 32b & 64b functions
Cut down on duplication by generalizing the ATOMIC_OP(),
ATOMIC_OP_RETURN() & ATOMIC_FETCH_OP() macros to work for both 32b &
64b atomics, and removing the ATOMIC64_ variants. This ensures
consistency between our atomic_* & atomic64_* functions.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:29 -07:00
Paul Burton
9537db24c6
MIPS: atomic: Handle !kernel_uses_llsc first
Handle the !kernel_uses_llsc path first in our ATOMIC_OP(),
ATOMIC_OP_RETURN() & ATOMIC_FETCH_OP() macros & return from within the
block. This allows us to de-indent the kernel_uses_llsc path by one
level which will be useful when making further changes.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:27 -07:00
Paul Burton
36d3295c5a
MIPS: atomic: Fix whitespace in ATOMIC_OP macros
We define macros in asm/atomic.h which end each line with space
characters before a backslash to continue on the next line. Remove the
space characters leaving tabs as the whitespace used for conformity with
coding convention.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:26 -07:00
Paul Burton
185d7d7a58
MIPS: barrier: Clean up sync_ginv()
Use the new __SYNC() infrastructure to implement sync_ginv(), for
consistency with much of the rest of the asm/barrier.h.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:24 -07:00
Paul Burton
fe0065e562
MIPS: barrier: Clean up __sync() definition
Implement __sync() using the new __SYNC() infrastructure, which will
take care of not emitting an instruction for old R3k CPUs that don't
support it. The only behavioral difference is that __sync() will now
provide a compiler barrier on these old CPUs, but that seems like
reasonable behavior anyway.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:22 -07:00
Paul Burton
5c12a6eff6
MIPS: barrier: Remove fast_mb() Octeon #ifdef'ery
The definition of fast_mb() is the same in both the Octeon & non-Octeon
cases, so remove the duplication & define it only once.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:21 -07:00
Paul Burton
05e6da742b
MIPS: barrier: Clean up __smp_mb() definition
We #ifdef on Cavium Octeon CPUs, but emit the same sync instruction in
both cases. Remove the #ifdef & simply expand to the __sync() macro.

Whilst here indent the strong ordering case definitions to match the
indentation of the weak ordering ones, helping readability.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:20 -07:00
Paul Burton
21e3134b3e
MIPS: barrier: Clean up rmb() & wmb() definitions
Simplify our definitions of rmb() & wmb() using the new __SYNC()
infrastructure.

The fast_rmb() & fast_wmb() macros are removed, since they only provided
a level of indirection that made the code less readable & weren't
directly used anywhere in the kernel tree.

The Octeon #ifdef'ery is removed, since the "syncw" instruction
previously used is merely an alias for "sync 4" which __SYNC() will emit
for the wmb sync type when the kernel is configured for an Octeon CPU.
Similarly __SYNC() will emit nothing for the rmb sync type in Octeon
configurations.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:18 -07:00
Paul Burton
bf92927251
MIPS: barrier: Add __SYNC() infrastructure
Introduce an asm/sync.h header which provides infrastructure that can be
used to generate sync instructions of various types, and for various
reasons. For example if we need a sync instruction that provides a full
completion barrier but only on systems which have weak memory ordering,
we can generate the appropriate assembly code using:

  __SYNC(full, weak_ordering)

When the kernel is configured to run on systems with weak memory
ordering (ie. CONFIG_WEAK_ORDERING is selected) we'll emit a sync
instruction. When the kernel is configured to run on systems with strong
memory ordering (ie. CONFIG_WEAK_ORDERING is not selected) we'll emit
nothing. The caller doesn't need to know which happened - it simply says
what it needs & when, with no concern for checking the kernel
configuration.

There are some scenarios in which we may want to emit code only when we
*didn't* emit a sync instruction. For example, some Loongson3 CPUs
suffer from a bug that requires us to emit a sync instruction prior to
each ll instruction (enabled by CONFIG_CPU_LOONGSON3_WORKAROUNDS). In
cases where this bug workaround is enabled, it's wasteful to then have
more generic code emit another sync instruction to provide barriers we
need in general. A __SYNC_ELSE() macro allows for this, providing an
extra argument that contains code to be assembled only in cases where
the sync instruction was not emitted. For example if we have a scenario
in which we generally want to emit a release barrier but for affected
Loongson3 configurations upgrade that to a full completion barrier, we
can do that like so:

  __SYNC_ELSE(full, loongson3_war, __SYNC(rl, always))

The assembly generated by these macros can be used either as inline
assembly or in assembly source files.

Differing types of sync as provided by MIPSr6 are defined, but currently
they all generate a full completion barrier except in kernels configured
for Cavium Octeon systems. There the wmb sync-type is used, and rmb
syncs are omitted, as has been the case since commit 6b07d38aaa
("MIPS: Octeon: Use optimized memory barrier primitives."). Using
__SYNC() with the wmb or rmb types will abstract away the Octeon
specific behavior and allow us to later clean up asm/barrier.h code that
currently includes a plethora of #ifdef's.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:17 -07:00
Paul Burton
ef85d057a6
MIPS: Use compact branch for LL/SC loops on MIPSr6+
When targeting MIPSr6 or higher make use of a compact branch in LL/SC
loops, preventing the insertion of a delay slot nop that only serves to
waste space.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:14 -07:00
Paul Burton
878f75c7a2
MIPS: Unify sc beqz definition
We currently duplicate the definition of __scbeqz in asm/atomic.h &
asm/cmpxchg.h. Move it to asm/llsc.h & rename it to __SC_BEQZ to fit
better with the existing __SC macro provided there.

We include a tab in the string in order to avoid the need for users to
indent code any further to include whitespace of their own after the
instruction mnemonic.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:42:13 -07:00
Stefan Roese
376357aca7
MIPS: ralink: Add GARDENA smart Gateway MT7688 board
This patch adds support for the GARDENA smart Gateway, which is based on
the MediaTek MT7688 SoC. It is equipped with 128 MiB of DDR and 8 MiB of
flash (SPI NOR) and additional 128MiB SPI NAND storage.

Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Harvey Hunt <harveyhuntnexus@gmail.com>
Cc: John Crispin <john@phrozen.org>
Cc: linux-mips@vger.kernel.org
2019-10-07 09:41:35 -07:00
Stefan Roese
cd5f9e4fd8
MIPS: ralink: mt7628a.dtsi: Add I2C controller DT node
This patch adds the I2C controller description to the MT7628A dtsi file.

Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Harvey Hunt <harveyhuntnexus@gmail.com>
Cc: John Crispin <john@phrozen.org>
Cc: linux-mips@vger.kernel.org
2019-10-07 09:41:10 -07:00
Paul Burton
5045d06b37
MIPS: r4k-bugs64: Drop CONFIG_CPU_MIPSR6 checks
The r4k-bugs64 code will no longer be built for MIPSr6 kernel
configurations, so there's no need to perform checks for MIPSr6 within
the code. Drop those redundant checks.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
2019-10-07 09:38:54 -07:00
Paul Burton
071d2f0b54
MIPS: r4k-bugs64: Limit R4k bug checks to affected systems
Only build the checks for R4k errata workarounds if we expect that the
kernel might actually run on a system with an R4k CPU - ie.
CONFIG_SYS_HAS_CPU_R4X00=y & we're targeting a pre-MIPSr1 ISA revision.

Rename cpu-bugs64.c to r4k-bugs64.c to indicate the fact that the code
is specific to R4k CPUs.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
2019-10-07 09:38:53 -07:00
Thomas Bogendoerfer
4bf841ebf1
MIPS: SGI-IP27: get rid of compact node ids
Node ids don't need to be contiguous in Linux, so the concept to
use compact node ids to make them contiguous isn't needed at all.
This patchset therefore removes it.

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:37:59 -07:00
Thomas Bogendoerfer
46a73e9e6c
MIPS: SGI-IP27: remove not used stuff inherited from IRIX
Most of the SN/SN0 header files are inherited from IRIX header files,
but not all of that stuff is useful for Linux. Remove not used parts.

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:37:53 -07:00
Paul Burton
6822c29ddb
MIPS: fw/arc: Remove unused addr variable
The addr variable in prom_free_prom_memory() has been unused since
commit 0df1007677 ("MIPS: fw: Record prom memory"), leading to a
compiler warning:

  arch/mips/fw/arc/memory.c:163:16:
    warning: unused variable 'addr' [-Wunused-variable]

Fix this by removing the unused variable.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 0df1007677 ("MIPS: fw: Record prom memory")
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-mips@vger.kernel.org
2019-10-04 11:46:22 -07:00
Paul Burton
437450cf09
MIPS: pmcs-msp71xx: Remove unused addr variable
The addr variable in prom_free_prom_memory() has been unused since
commit b3c948e2c0 ("MIPS: msp: Record prom memory"), causing a warning
& build failure due to -Werror. Remove the unused variable.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: b3c948e2c0 ("MIPS: msp: Record prom memory")
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-mips@vger.kernel.org
2019-10-03 15:47:17 -07:00
Paul Burton
101c40ed26
MIPS: pmcs-msp71xx: Add missing MAX_PROM_MEM definition
Commit b3c948e2c0 ("MIPS: msp: Record prom memory") introduced use of
a MAX_PROM_MEM value but didn't define it. A bounds check in
prom_meminit() suggests its value was supposed to be 5, so define it as
such & adjust the bounds check to use the macro rather than a magic
number.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: b3c948e2c0 ("MIPS: msp: Record prom memory")
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-mips@vger.kernel.org
2019-10-03 15:47:14 -07:00
Christophe JAILLET
25b69a889b
mips: Loongson: Fix the link time qualifier of 'serial_exit()'
'exit' functions should be marked as __exit, not __init.

Fixes: 85cc028817 ("mips: make loongsoon serial driver explicitly modular")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: chenhc@lemote.com
Cc: ralf@linux-mips.org
Cc: jhogan@kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: kernel-janitors@vger.kernel.org
2019-10-02 14:16:32 -07:00
Thomas Bogendoerfer
bd848d1b92
MIPS: init: Prevent adding memory before PHYS_OFFSET
On some SGI machines (IP28 and IP30) a small region of memory is mirrored
to pyhsical address 0 for exception vectors while rest of the memory
is reachable at a higher physical address. ARC PROM marks this
region as reserved, but with commit a94e4f24ec ("MIPS: init: Drop
boot_mem_map") this chunk is used, when searching for start of ram,
which breaks at least IP28 and IP30 machines. To fix this
add_region_memory() checks for start address < PHYS_OFFSET and ignores
these chunks.

Fixes: a94e4f24ec ("MIPS: init: Drop boot_mem_map")
Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
2019-10-02 14:11:30 -07:00
Thomas Bogendoerfer
66b416ee41
MIPS: init: Fix reservation of memory between PHYS_OFFSET and mem start
Fix calculation of the size for reserving memory between PHYS_OFFSET
and real memory start.

Fixes: a94e4f24ec ("MIPS: init: Drop boot_mem_map")
Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
2019-10-02 14:10:16 -07:00
Paul Burton
8919975b61
MIPS: VDSO: Fix build for binutils < 2.25
Versions of binutils prior to 2.25 are unable to link our VDSO due to an
unsupported R_MIPS_PC32 relocation generated by the ".word _start - ."
line of the inline asm in get_vdso_base(). As such, the intent is that
when building with binutils older than 2.25 we don't build code for
gettimeofday() & friends in the VDSO that rely upon get_vdso_base().

Commit 24640f233b ("mips: Add support for generic vDSO") converted us
to using generic VDSO infrastructure, and as part of that the
gettimeofday() functionality moved to a new vgettimeofday.c file. The
check for binutils < 2.25 wasn't updated to handle this new filename,
and so it continues trying to remove the old unused filename from the
build. The end result is that we try to include the gettimeofday() code
in builds that will fail to link.

Fix this by updating the binutils < 2.25 case to remove vgettimeofday.c
from obj-vdso-y, rather than gettimeofday.c.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 24640f233b ("mips: Add support for generic vDSO")
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: linux-mips@vger.kernel.org
2019-10-02 14:07:32 -07:00
Paul Burton
90800281e7
MIPS: VDSO: Remove unused gettimeofday.c
arch/mips/vdso/gettimeofday.c has been unused since commit 24640f233b
("mips: Add support for generic vDSO"). Remove the dead code.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 24640f233b ("mips: Add support for generic vDSO")
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: linux-mips@vger.kernel.org
2019-10-02 14:07:30 -07:00
Paul Burton
0671c5b84e
MIPS: Wire up clone3 syscall
Wire up the new clone3 syscall for MIPS, using save_static_function() to
generate a wrapper that saves registers $s0-$s7 prior to invoking the
generic sys_clone3 function just like we do for plain old clone.

Tested atop 64r6el_defconfig using o32, n32 & n64 builds of the simple
test program from:

  https://lore.kernel.org/lkml/20190716130631.tohj4ub54md25dys@brauner.io/

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Christian Brauner <christian@brauner.io>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: linux-mips@vger.kernel.org
2019-10-02 14:06:41 -07:00
Paul Burton
0228ecf612
MIPS: octeon: Include required header; fix octeon ethernet build
Commit 171a9bae68 ("staging/octeon: Allow test build on !MIPS") moved
the inclusion of a bunch of headers by various files in the Octeon
ethernet driver into a common header, but in doing so it changed the
order in which those headers are included.

Prior to the referenced commit drivers/staging/octeon/ethernet.c
included asm/octeon/cvmx-pip.h before asm/octeon/cvmx-ipd.h, which makes
use of the CVMX_PIP_SFT_RST definition pulled in by the former. After
commit 171a9bae68 ("staging/octeon: Allow test build on !MIPS") we
pull in asm/octeon/cvmx-ipd.h first & builds fail with:

  In file included from drivers/staging/octeon/octeon-ethernet.h:27,
                   from drivers/staging/octeon/ethernet.c:22:
  arch/mips/include/asm/octeon/cvmx-ipd.h: In function 'cvmx_ipd_free_ptr':
  arch/mips/include/asm/octeon/cvmx-ipd.h:330:27: error: storage size of
    'pip_sft_rst' isn't known
      union cvmx_pip_sft_rst pip_sft_rst;
                             ^~~~~~~~~~~
  arch/mips/include/asm/octeon/cvmx-ipd.h:331:36: error: 'CVMX_PIP_SFT_RST'
    undeclared (first use in this function); did you mean 'CVMX_CIU_SOFT_RST'?
      pip_sft_rst.u64 = cvmx_read_csr(CVMX_PIP_SFT_RST);
                                      ^~~~~~~~~~~~~~~~
                                      CVMX_CIU_SOFT_RST
  arch/mips/include/asm/octeon/cvmx-ipd.h:331:36: note: each undeclared
    identifier is reported only once for each function it appears in
  arch/mips/include/asm/octeon/cvmx-ipd.h:330:27: warning: unused variable
    'pip_sft_rst' [-Wunused-variable]
      union cvmx_pip_sft_rst pip_sft_rst;
                             ^~~~~~~~~~~
  make[4]: *** [scripts/Makefile.build:266: drivers/staging/octeon/ethernet.o]
    Error 1
  make[3]: *** [scripts/Makefile.build:509: drivers/staging/octeon] Error 2

Fix this by having asm/octeon/cvmx-ipd.h include the
asm/octeon/cvmx-pip-defs.h header that it is reliant upon, rather than
requiring its users to pull in that header before it.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 171a9bae68 ("staging/octeon: Allow test build on !MIPS")
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: linux-mips@vger.kernel.org
Cc: David S . Miller <davem@davemloft.net>
Cc: Matthew Wilcox <willy@infradead.org>
2019-10-02 10:08:20 -07:00
Jiaxun Yang
d345d9cad2
MIPS: cpu-bugs64: Mark inline functions as __always_inline
Commit ac7c3e4ff4 ("compiler: enable CONFIG_OPTIMIZE_INLINING
forcibly") allows compiler to uninline functions marked as 'inline'.
Leading to section mismatch in this case.

Since we're using const variables to pass assembly flags, 'inline's
can't be dropped. So we simply mark them as __always_inline.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-mips@vger.kernel.org
[paul.burton@mips.com:
  - Annotate these functions with __init, even if it only serves to
    inform human readers when the code can be used.
  - Drop the __always_inline from check_daddi() & check_daddiu() which
    don't use arguments as immediates in inline asm.
  - Rewrap the commit message.]
Signed-off-by: Paul Burton <paul.burton@mips.com>
2019-10-01 12:59:59 -07:00