4 files changed, 39 insertions, 0 deletions

diff --git a/arch/parisc/include/asm/barrier.h b/arch/parisc/include/asm/barrier.h
new file mode 100644
index 000000000000..dbaaca84f27f
--- /dev/null
+++ b/arch/parisc/include/asm/barrier.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_BARRIER_H
+#define __ASM_BARRIER_H
+
+#ifndef __ASSEMBLY__
+
+/* The synchronize caches instruction executes as a nop on systems in
+   which all memory references are performed in order. */
+#define synchronize_caches() __asm__ __volatile__ ("sync" : : : "memory")
+
+#if defined(CONFIG_SMP)
+#define mb()            do { synchronize_caches(); } while (0)
+#define rmb()           mb()
+#define wmb()           mb()
+#define dma_rmb()       mb()
+#define dma_wmb()       mb()
+#else
+#define mb()            barrier()
+#define rmb()           barrier()
+#define wmb()           barrier()
+#define dma_rmb()       barrier()
+#define dma_wmb()       barrier()
+#endif
+
+#define __smp_mb()      mb()
+#define __smp_rmb()     mb()
+#define __smp_wmb()     mb()
+
+#include <asm-generic/barrier.h>
+
+#endif /* !__ASSEMBLY__ */
+#endif /* __ASM_BARRIER_H */
diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S
index e95207c0565e..1b4732e20137 100644
--- a/arch/parisc/kernel/entry.S
+++ b/arch/parisc/kernel/entry.S
@@ -482,6 +482,8 @@
         .macro          tlb_unlock0     spc,tmp
 #ifdef CONFIG_SMP
         or,COND(=)      %r0,\spc,%r0
+        sync
+        or,COND(=)      %r0,\spc,%r0
         stw             \spc,0(\tmp)
 #endif
         .endm
diff --git a/arch/parisc/kernel/pacache.S b/arch/parisc/kernel/pacache.S
index 22e6374ece44..97451e67d35b 100644
--- a/arch/parisc/kernel/pacache.S
+++ b/arch/parisc/kernel/pacache.S
@@ -353,6 +353,7 @@ ENDPROC_CFI(flush_data_cache_local)
         .macro  tlb_unlock      la,flags,tmp
 #ifdef CONFIG_SMP
         ldi             1,\tmp
+        sync
         stw             \tmp,0(\la)
         mtsm            \flags
 #endif
diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S
index e775f80ae28c..4886a6db42e9 100644
--- a/arch/parisc/kernel/syscall.S
+++ b/arch/parisc/kernel/syscall.S
@@ -633,6 +633,7 @@ cas_action:
         sub,<>  %r28, %r25, %r0
 2:      stw,ma  %r24, 0(%r26)
         /* Free lock */
+        sync
         stw,ma  %r20, 0(%sr2,%r20)
 #if ENABLE_LWS_DEBUG
         /* Clear thread register indicator */
@@ -647,6 +648,7 @@ cas_action:
 3:              
         /* Error occurred on load or store */
         /* Free lock */
+        sync
         stw     %r20, 0(%sr2,%r20)
 #if ENABLE_LWS_DEBUG
         stw     %r0, 4(%sr2,%r20)
@@ -848,6 +850,7 @@ cas2_action:
 
 cas2_end:
         /* Free lock */
+        sync
         stw,ma  %r20, 0(%sr2,%r20)
         /* Enable interrupts */
         ssm     PSW_SM_I, %r0
@@ -858,6 +861,7 @@ cas2_end:
 22:
         /* Error occurred on load or store */
         /* Free lock */
+        sync
         stw     %r20, 0(%sr2,%r20)
         ssm     PSW_SM_I, %r0
         ldo     1(%r0),%r28