parisc: Also flush data TLB in flush_icache_page_asm

This is the second issue I noticed in reviewing the parisc TLB code.

The fic instruction may use either the instruction or data TLB in
flushing the instruction cache.  Thus, on machines with a split TLB, we
should also flush the data TLB after setting up the temporary alias
registers.

Although this has no functional impact, I changed the pdtlb and pitlb
instructions to consistently use the index register %r0.  These
instructions do not support integer displacements.

Tested on rp3440 and c8000.

Signed-off-by: John David Anglin  <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org> # v3.16+
Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/arch/parisc/kernel/pacache.S b/arch/parisc/kernel/pacache.S
index 985e06da37f5163fd6ea566024c9f6e82d9db607..1b39a2acaadf43f16df3a54f3a797b029a3e06ff 100644 (file)
--- a/arch/parisc/kernel/pacache.S
+++ b/arch/parisc/kernel/pacache.S
@@ -96,7 +96,7 @@ fitmanyloop:                                  /* Loop if LOOP >= 2 */
 
 fitmanymiddle:                                 /* Loop if LOOP >= 2 */
        addib,COND(>)           -1, %r31, fitmanymiddle /* Adjusted inner loop decr */
-       pitlbe          0(%sr1, %r28)
+       pitlbe          %r0(%sr1, %r28)
        pitlbe,m        %arg1(%sr1, %r28)       /* Last pitlbe and addr adjust */
        addib,COND(>)           -1, %r29, fitmanymiddle /* Middle loop decr */
        copy            %arg3, %r31             /* Re-init inner loop count */
@@ -139,7 +139,7 @@ fdtmanyloop:                                        /* Loop if LOOP >= 2 */
 
 fdtmanymiddle:                                 /* Loop if LOOP >= 2 */
        addib,COND(>)           -1, %r31, fdtmanymiddle /* Adjusted inner loop decr */
-       pdtlbe          0(%sr1, %r28)
+       pdtlbe          %r0(%sr1, %r28)
        pdtlbe,m        %arg1(%sr1, %r28)       /* Last pdtlbe and addr adjust */
        addib,COND(>)           -1, %r29, fdtmanymiddle /* Middle loop decr */
        copy            %arg3, %r31             /* Re-init inner loop count */
@@ -626,12 +626,12 @@ ENTRY_CFI(copy_user_page_asm)
        /* Purge any old translations */
 
 #ifdef CONFIG_PA20
-       pdtlb,l         0(%r28)
-       pdtlb,l         0(%r29)
+       pdtlb,l         %r0(%r28)
+       pdtlb,l         %r0(%r29)
 #else
        tlb_lock        %r20,%r21,%r22
-       pdtlb           0(%r28)
-       pdtlb           0(%r29)
+       pdtlb           %r0(%r28)
+       pdtlb           %r0(%r29)
        tlb_unlock      %r20,%r21,%r22
 #endif
 
@@ -774,10 +774,10 @@ ENTRY_CFI(clear_user_page_asm)
        /* Purge any old translation */
 
 #ifdef CONFIG_PA20
-       pdtlb,l         0(%r28)
+       pdtlb,l         %r0(%r28)
 #else
        tlb_lock        %r20,%r21,%r22
-       pdtlb           0(%r28)
+       pdtlb           %r0(%r28)
        tlb_unlock      %r20,%r21,%r22
 #endif
 
@@ -858,10 +858,10 @@ ENTRY_CFI(flush_dcache_page_asm)
        /* Purge any old translation */
 
 #ifdef CONFIG_PA20
-       pdtlb,l         0(%r28)
+       pdtlb,l         %r0(%r28)
 #else
        tlb_lock        %r20,%r21,%r22
-       pdtlb           0(%r28)
+       pdtlb           %r0(%r28)
        tlb_unlock      %r20,%r21,%r22
 #endif
 
@@ -898,10 +898,10 @@ ENTRY_CFI(flush_dcache_page_asm)
        sync
 
 #ifdef CONFIG_PA20
-       pdtlb,l         0(%r25)
+       pdtlb,l         %r0(%r25)
 #else
        tlb_lock        %r20,%r21,%r22
-       pdtlb           0(%r25)
+       pdtlb           %r0(%r25)
        tlb_unlock      %r20,%r21,%r22
 #endif
 
@@ -931,13 +931,18 @@ ENTRY_CFI(flush_icache_page_asm)
        depwi           0, 31,PAGE_SHIFT, %r28  /* Clear any offset bits */
 #endif
 
-       /* Purge any old translation */
+       /* Purge any old translation.  Note that the FIC instruction
+        * may use either the instruction or data TLB.  Given that we
+        * have a flat address space, it's not clear which TLB will be
+        * used.  So, we purge both entries.  */
 
 #ifdef CONFIG_PA20
+       pdtlb,l         %r0(%r28)
        pitlb,l         %r0(%sr4,%r28)
 #else
        tlb_lock        %r20,%r21,%r22
-       pitlb           (%sr4,%r28)
+       pdtlb           %r0(%r28)
+       pitlb           %r0(%sr4,%r28)
        tlb_unlock      %r20,%r21,%r22
 #endif
 
@@ -976,10 +981,12 @@ ENTRY_CFI(flush_icache_page_asm)
        sync
 
 #ifdef CONFIG_PA20
+       pdtlb,l         %r0(%r28)
        pitlb,l         %r0(%sr4,%r25)
 #else
        tlb_lock        %r20,%r21,%r22
-       pitlb           (%sr4,%r25)
+       pdtlb           %r0(%r28)
+       pitlb           %r0(%sr4,%r25)
        tlb_unlock      %r20,%r21,%r22
 #endif