Ensure the update to which core the core-other GCR regions reflect has
taken place before any core-other GCRs are accessed by placing a memory
barrier (sync instruction) between the write to the core-other registers
and any such GCR accesses.

Signed-off-by: Paul Burton <[email protected]>
---

 arch/mips/kernel/mips-cm.c  | 6 ++++++
 arch/mips/kernel/mips-cpc.c | 6 ++++++
 2 files changed, 12 insertions(+)

diff --git a/arch/mips/kernel/mips-cm.c b/arch/mips/kernel/mips-cm.c
index fef2647..485e441 100644
--- a/arch/mips/kernel/mips-cm.c
+++ b/arch/mips/kernel/mips-cm.c
@@ -278,6 +278,12 @@ void mips_cm_lock_other(unsigned int core, unsigned int vp)
        }
 
        write_gcr_cl_other(val);
+
+       /*
+        * Ensure the core-other region reflects the appropriate core &
+        * VP before any accesses to it occur.
+        */
+       mb();
 }
 
 void mips_cm_unlock_other(void)
diff --git a/arch/mips/kernel/mips-cpc.c b/arch/mips/kernel/mips-cpc.c
index 8af4d62..566b8d2 100644
--- a/arch/mips/kernel/mips-cpc.c
+++ b/arch/mips/kernel/mips-cpc.c
@@ -76,6 +76,12 @@ void mips_cpc_lock_other(unsigned int core)
        spin_lock_irqsave(&per_cpu(cpc_core_lock, curr_core),
                          per_cpu(cpc_core_lock_flags, curr_core));
        write_cpc_cl_other(core << CPC_Cx_OTHER_CORENUM_SHF);
+
+       /*
+        * Ensure the core-other region reflects the appropriate core &
+        * VP before any accesses to it occur.
+        */
+       mb();
 }
 
 void mips_cpc_unlock_other(void)
-- 
2.5.3

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