1. 07 Oct, 2019 37 commits
    • Paul Burton's avatar
      MIPS: cmpxchg: Omit redundant barriers for Loongson3 · a91f2a1d
      Paul Burton authored
      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: default avatarPaul 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
      a91f2a1d
    • Paul Burton's avatar
      MIPS: cmpxchg: Emit Loongson3 sync workarounds within asm · 6a57d2d1
      Paul Burton authored
      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: default avatarPaul 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
      6a57d2d1
    • Paul Burton's avatar
      MIPS: bitops: Use smp_mb__before_atomic in test_* ops · 90267377
      Paul Burton authored
      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: default avatarPaul 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
      90267377
    • Paul Burton's avatar
      MIPS: bitops: Emit Loongson3 sync workarounds within asm · 5bb29275
      Paul Burton authored
      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: default avatarPaul 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
      5bb29275
    • Paul Burton's avatar
      MIPS: bitops: Use BIT_WORD() & BITS_PER_LONG · c042be02
      Paul Burton authored
      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: default avatarPaul 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
      c042be02
    • Paul Burton's avatar
      MIPS: bitops: Abstract LL/SC loops · cc99987c
      Paul Burton authored
      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: default avatarPaul 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
      cc99987c
    • Paul Burton's avatar
      MIPS: bitops: Avoid redundant zero-comparison for non-LLSC · aad028ca
      Paul Burton authored
      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: default avatarPaul 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
      aad028ca
    • Paul Burton's avatar
      MIPS: bitops: Use the BIT() macro · d6103510
      Paul Burton authored
      Use the BIT() macro in asm/bitops.h rather than open-coding its
      equivalent.
      Signed-off-by: default avatarPaul 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
      d6103510
    • Paul Burton's avatar
      MIPS: bitops: Allow immediates in test_and_{set,clear,change}_bit · a2e66b86
      Paul Burton authored
      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: default avatarPaul 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
      a2e66b86
    • Paul Burton's avatar
      MIPS: bitops: Implement test_and_set_bit() in terms of _lock variant · 6bbe043b
      Paul Burton authored
      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: default avatarPaul 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
      6bbe043b
    • Paul Burton's avatar
      MIPS: bitops: ins start position is always an immediate · 27aab272
      Paul Burton authored
      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: default avatarPaul 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
      27aab272
    • Paul Burton's avatar
      MIPS: bitops: Use MIPS_ISA_REV, not #ifdefs · 59361e99
      Paul Burton authored
      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: default avatarPaul 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
      59361e99
    • Paul Burton's avatar
      MIPS: bitops: Only use ins for bit 16 or higher · 3d2920cf
      Paul Burton authored
      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: default avatarPaul 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
      3d2920cf
    • Paul Burton's avatar
      MIPS: bitops: Handle !kernel_uses_llsc first · fe7cd97e
      Paul Burton authored
      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: default avatarPaul 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
      fe7cd97e
    • Paul Burton's avatar
      MIPS: atomic: Deduplicate 32b & 64b read, set, xchg, cmpxchg · 1da7bce8
      Paul Burton authored
      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: default avatarPaul 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
      1da7bce8
    • Paul Burton's avatar
      MIPS: atomic: Unify 32b & 64b sub_if_positive · 40e784b4
      Paul Burton authored
      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: default avatarPaul 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
      40e784b4
    • Paul Burton's avatar
      MIPS: atomic: Use _atomic barriers in atomic_sub_if_positive() · 77d281b7
      Paul Burton authored
      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: default avatarPaul 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
      77d281b7
    • Paul Burton's avatar
      MIPS: atomic: Emit Loongson3 sync workarounds within asm · 4d1dbfe6
      Paul Burton authored
      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: default avatarPaul 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
      4d1dbfe6
    • Paul Burton's avatar
      MIPS: atomic: Use one macro to generate 32b & 64b functions · a38ee6bb
      Paul Burton authored
      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: default avatarPaul 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
      a38ee6bb
    • Paul Burton's avatar
      MIPS: atomic: Handle !kernel_uses_llsc first · 9537db24
      Paul Burton authored
      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: default avatarPaul 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
      9537db24
    • Paul Burton's avatar
      MIPS: atomic: Fix whitespace in ATOMIC_OP macros · 36d3295c
      Paul Burton authored
      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: default avatarPaul 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
      36d3295c
    • Paul Burton's avatar
      MIPS: barrier: Clean up sync_ginv() · 185d7d7a
      Paul Burton authored
      Use the new __SYNC() infrastructure to implement sync_ginv(), for
      consistency with much of the rest of the asm/barrier.h.
      Signed-off-by: default avatarPaul 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
      185d7d7a
    • Paul Burton's avatar
      MIPS: barrier: Clean up __sync() definition · fe0065e5
      Paul Burton authored
      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: default avatarPaul 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
      fe0065e5
    • Paul Burton's avatar
      MIPS: barrier: Remove fast_mb() Octeon #ifdef'ery · 5c12a6ef
      Paul Burton authored
      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: default avatarPaul 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
      5c12a6ef
    • Paul Burton's avatar
      MIPS: barrier: Clean up __smp_mb() definition · 05e6da74
      Paul Burton authored
      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: default avatarPaul 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
      05e6da74
    • Paul Burton's avatar
      MIPS: barrier: Clean up rmb() & wmb() definitions · 21e3134b
      Paul Burton authored
      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: default avatarPaul 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
      21e3134b
    • Paul Burton's avatar
      MIPS: barrier: Add __SYNC() infrastructure · bf929272
      Paul Burton authored
      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 6b07d38a
      ("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: default avatarPaul 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
      bf929272
    • Paul Burton's avatar
      MIPS: Use compact branch for LL/SC loops on MIPSr6+ · ef85d057
      Paul Burton authored
      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: default avatarPaul 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
      ef85d057
    • Paul Burton's avatar
      MIPS: Unify sc beqz definition · 878f75c7
      Paul Burton authored
      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: default avatarPaul 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
      878f75c7
    • Stefan Roese's avatar
      MIPS: ralink: Add GARDENA smart Gateway MT7688 board · 376357ac
      Stefan Roese authored
      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: default avatarStefan Roese <sr@denx.de>
      Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
      Cc: Harvey Hunt <harveyhuntnexus@gmail.com>
      Cc: John Crispin <john@phrozen.org>
      Cc: linux-mips@vger.kernel.org
      376357ac
    • Stefan Roese's avatar
      dt-bindings: mips: Add gardena vendor prefix and board description · 4ce8a03c
      Stefan Roese authored
      This patch adds the vendor prefix for gardena and a short description
      including the compatible string for the "GARDENA smart Gateway" based
      on the MT7688 SoC.
      Signed-off-by: default avatarStefan Roese <sr@denx.de>
      Reviewed-by: default avatarRob Herring <robh@kernel.org>
      Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
      Cc: devicetree@vger.kernel.org
      Cc: linux-mips@vger.kernel.org
      4ce8a03c
    • Stefan Roese's avatar
      dt-bindings: mips: Add missing mt7688a-soc compatible · cf892abf
      Stefan Roese authored
      This patch adds the "ralink,mt7688a-soc" compatible to the ralink DT
      bindings documentation. This compatible is already used by some MIPS
      boards (e.g. omega2p.dts) but not yet documented. It will also be used
      by the upcoming "GARDENA smart Gateway" support.
      Signed-off-by: default avatarStefan Roese <sr@denx.de>
      Reviewed-by: default avatarRob Herring <robh@kernel.org>
      Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
      Cc: devicetree@vger.kernel.org
      Cc: linux-mips@vger.kernel.org
      cf892abf
    • Stefan Roese's avatar
      MIPS: ralink: mt7628a.dtsi: Add I2C controller DT node · cd5f9e4f
      Stefan Roese authored
      This patch adds the I2C controller description to the MT7628A dtsi file.
      Signed-off-by: default avatarStefan Roese <sr@denx.de>
      Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
      Cc: Harvey Hunt <harveyhuntnexus@gmail.com>
      Cc: John Crispin <john@phrozen.org>
      Cc: linux-mips@vger.kernel.org
      cd5f9e4f
    • Paul Burton's avatar
      MIPS: r4k-bugs64: Drop CONFIG_CPU_MIPSR6 checks · 5045d06b
      Paul Burton authored
      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: default avatarPaul Burton <paul.burton@mips.com>
      Cc: linux-mips@vger.kernel.org
      5045d06b
    • Paul Burton's avatar
      MIPS: r4k-bugs64: Limit R4k bug checks to affected systems · 071d2f0b
      Paul Burton authored
      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: default avatarPaul Burton <paul.burton@mips.com>
      Cc: linux-mips@vger.kernel.org
      071d2f0b
    • Thomas Bogendoerfer's avatar
      MIPS: SGI-IP27: get rid of compact node ids · 4bf841eb
      Thomas Bogendoerfer authored
      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: default avatarThomas Bogendoerfer <tbogendoerfer@suse.de>
      Signed-off-by: default avatarPaul 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
      4bf841eb
    • Thomas Bogendoerfer's avatar
      MIPS: SGI-IP27: remove not used stuff inherited from IRIX · 46a73e9e
      Thomas Bogendoerfer authored
      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: default avatarThomas Bogendoerfer <tbogendoerfer@suse.de>
      Signed-off-by: default avatarPaul 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
      46a73e9e
  2. 06 Oct, 2019 3 commits
    • Linus Torvalds's avatar
      Linux 5.4-rc2 · da0c9ea1
      Linus Torvalds authored
      da0c9ea1
    • Linus Torvalds's avatar
      elf: don't use MAP_FIXED_NOREPLACE for elf executable mappings · b212921b
      Linus Torvalds authored
      In commit 4ed28639 ("fs, elf: drop MAP_FIXED usage from elf_map") we
      changed elf to use MAP_FIXED_NOREPLACE instead of MAP_FIXED for the
      executable mappings.
      
      Then, people reported that it broke some binaries that had overlapping
      segments from the same file, and commit ad55eac7 ("elf: enforce
      MAP_FIXED on overlaying elf segments") re-instated MAP_FIXED for some
      overlaying elf segment cases.  But only some - despite the summary line
      of that commit, it only did it when it also does a temporary brk vma for
      one obvious overlapping case.
      
      Now Russell King reports another overlapping case with old 32-bit x86
      binaries, which doesn't trigger that limited case.  End result: we had
      better just drop MAP_FIXED_NOREPLACE entirely, and go back to MAP_FIXED.
      
      Yes, it's a sign of old binaries generated with old tool-chains, but we
      do pride ourselves on not breaking existing setups.
      
      This still leaves MAP_FIXED_NOREPLACE in place for the load_elf_interp()
      and the old load_elf_library() use-cases, because nobody has reported
      breakage for those. Yet.
      
      Note that in all the cases seen so far, the overlapping elf sections
      seem to be just re-mapping of the same executable with different section
      attributes.  We could possibly introduce a new MAP_FIXED_NOFILECHANGE
      flag or similar, which acts like NOREPLACE, but allows just remapping
      the same executable file using different protection flags.
      
      It's not clear that would make a huge difference to anything, but if
      people really hate that "elf remaps over previous maps" behavior, maybe
      at least a more limited form of remapping would alleviate some concerns.
      
      Alternatively, we should take a look at our elf_map() logic to see if we
      end up not mapping things properly the first time.
      
      In the meantime, this is the minimal "don't do that then" patch while
      people hopefully think about it more.
      Reported-by: default avatarRussell King <linux@armlinux.org.uk>
      Fixes: 4ed28639 ("fs, elf: drop MAP_FIXED usage from elf_map")
      Fixes: ad55eac7 ("elf: enforce  MAP_FIXED on overlaying elf segments")
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Kees Cook <keescook@chromium.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      b212921b
    • Linus Torvalds's avatar
      Merge tag 'dma-mapping-5.4-1' of git://git.infradead.org/users/hch/dma-mapping · 7cdb85df
      Linus Torvalds authored
      Pull dma-mapping regression fix from Christoph Hellwig:
       "Revert an incorret hunk from a patch that caused problems on various
        arm boards (Andrey Smirnov)"
      
      * tag 'dma-mapping-5.4-1' of git://git.infradead.org/users/hch/dma-mapping:
        dma-mapping: fix false positive warnings in dma_common_free_remap()
      7cdb85df