target/linux/ramips/patches-4.3/0058-backport-ensure-core-other-GCR-reflect-correct-core.patch

   1 commit 78a54c4d8e5a7915a4ec2ba0eb461fae50590683
   2 Author: Paul Burton <paul.burton@imgtec.com>
   3 Date:   Tue Sep 22 11:12:18 2015 -0700
   4
   5     MIPS: CM, CPC: Ensure core-other GCRs reflect the correct core
   6
   7     Ensure the update to which core the core-other GCR regions reflect has
   8     taken place before any core-other GCRs are accessed by placing a memory
   9     barrier (sync instruction) between the write to the core-other registers
  10     and any such GCR accesses.
  11
  12     Signed-off-by: Paul Burton <paul.burton@imgtec.com>
  13     Cc: linux-mips@linux-mips.org
  14     Cc: Bjorn Helgaas <bhelgaas@google.com>
  15     Cc: linux-kernel@vger.kernel.org
  16     Cc: Markos Chandras <markos.chandras@imgtec.com>
  17     Patchwork: https://patchwork.linux-mips.org/patch/11209/
  18     Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
  19
  20 --- a/arch/mips/kernel/mips-cm.c
  21 +++ b/arch/mips/kernel/mips-cm.c
  22 @@ -278,6 +278,12 @@ void mips_cm_lock_other(unsigned int cor
  23         }
  24
  25         write_gcr_cl_other(val);
  26 +
  27 +       /*
  28 +        * Ensure the core-other region reflects the appropriate core &
  29 +        * VP before any accesses to it occur.
  30 +        */
  31 +       mb();
  32  }
  33
  34  void mips_cm_unlock_other(void)
  35 --- a/arch/mips/kernel/mips-cpc.c
  36 +++ b/arch/mips/kernel/mips-cpc.c
  37 @@ -76,6 +76,12 @@ void mips_cpc_lock_other(unsigned int co
  38         spin_lock_irqsave(&per_cpu(cpc_core_lock, curr_core),
  39                           per_cpu(cpc_core_lock_flags, curr_core));
  40         write_cpc_cl_other(core << CPC_Cx_OTHER_CORENUM_SHF);
  41 +
  42 +       /*
  43 +        * Ensure the core-other region reflects the appropriate core &
  44 +        * VP before any accesses to it occur.
  45 +        */
  46 +       mb();
  47  }
  48
  49  void mips_cpc_unlock_other(void)