powerpc: Fix 64bit memcpy() regression

[linux-2.6-block.git] / arch / powerpc / lib / memcpy_64.S

diff --git a/arch/powerpc/lib/memcpy_64.S b/arch/powerpc/lib/memcpy_64.S
index 3f131129d1c1a496607637f39eb1f563596768d0..e178922b2c2129e808a427464ce8fccc34643309 100644 (file)
--- a/arch/powerpc/lib/memcpy_64.S
+++ b/arch/powerpc/lib/memcpy_64.S
@@ -18,11 +18,23 @@ _GLOBAL(memcpy)
        andi.   r6,r6,7
        dcbt    0,r4
        blt     cr1,.Lshort_copy
+/* Below we want to nop out the bne if we're on a CPU that has the
+   CPU_FTR_UNALIGNED_LD_STD bit set and the CPU_FTR_CP_USE_DCBTZ bit
+   cleared.
+   At the time of writing the only CPU that has this combination of bits
+   set is Power6. */
+BEGIN_FTR_SECTION
+       nop
+FTR_SECTION_ELSE
        bne     .Ldst_unaligned
+ALT_FTR_SECTION_END(CPU_FTR_UNALIGNED_LD_STD | CPU_FTR_CP_USE_DCBTZ, \
+                    CPU_FTR_UNALIGNED_LD_STD)
 .Ldst_aligned:
-       andi.   r0,r4,7
        addi    r3,r3,-16
+BEGIN_FTR_SECTION
+       andi.   r0,r4,7
        bne     .Lsrc_unaligned
+END_FTR_SECTION_IFCLR(CPU_FTR_UNALIGNED_LD_STD)
        srdi    r7,r5,4
        ld      r9,0(r4)
        addi    r4,r4,-8
@@ -41,18 +53,19 @@ _GLOBAL(memcpy)
 3:     std     r8,8(r3)
        beq     3f
        addi    r3,r3,16
-       ld      r9,8(r4)
 .Ldo_tail:
        bf      cr7*4+1,1f
-       rotldi  r9,r9,32
+       lwz     r9,8(r4)
+       addi    r4,r4,4
        stw     r9,0(r3)
        addi    r3,r3,4
 1:     bf      cr7*4+2,2f
-       rotldi  r9,r9,16
+       lhz     r9,8(r4)
+       addi    r4,r4,2
        sth     r9,0(r3)
        addi    r3,r3,2
 2:     bf      cr7*4+3,3f
-       rotldi  r9,r9,8
+       lbz     r9,8(r4)
        stb     r9,0(r3)
 3:     ld      r3,48(r1)       /* return dest pointer */
        blr
@@ -121,17 +134,30 @@ _GLOBAL(memcpy)
        cmpwi   cr1,r5,8
        addi    r3,r3,32
        sld     r9,r9,r10
-       ble     cr1,.Ldo_tail
+       ble     cr1,6f
        ld      r0,8(r4)
        srd     r7,r0,r11
        or      r9,r7,r9
-       b       .Ldo_tail
+6:
+       bf      cr7*4+1,1f
+       rotldi  r9,r9,32
+       stw     r9,0(r3)
+       addi    r3,r3,4
+1:     bf      cr7*4+2,2f
+       rotldi  r9,r9,16
+       sth     r9,0(r3)
+       addi    r3,r3,2
+2:     bf      cr7*4+3,3f
+       rotldi  r9,r9,8
+       stb     r9,0(r3)
+3:     ld      r3,48(r1)       /* return dest pointer */
+       blr
 
 .Ldst_unaligned:
        PPC_MTOCRF      0x01,r6         # put #bytes to 8B bdry into cr7
        subf    r5,r6,r5
        li      r7,0
-       cmpldi  r1,r5,16
+       cmpldi  cr1,r5,16
        bf      cr7*4+3,1f
        lbz     r0,0(r4)
        stb     r0,0(r3)