microblaze: Support word copying in copy_tofrom_user
Word copying is used only for aligned addresses.
Here is space for improving to use any better copying technique.
Look at memcpy implementation.
Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/arch/microblaze/lib/uaccess_old.S b/arch/microblaze/lib/uaccess_old.S
index b327524..5810cec 100644
--- a/arch/microblaze/lib/uaccess_old.S
+++ b/arch/microblaze/lib/uaccess_old.S
@@ -53,7 +53,6 @@
nop
.size __strncpy_user, . - __strncpy_user
-
.section .fixup, "ax"
.align 2
4:
@@ -95,7 +94,6 @@
nop
.size __strnlen_user, . - __strnlen_user
-
.section .fixup,"ax"
4:
brid 3b
@@ -121,21 +119,34 @@
* r7, r3 - count
* r4 - tempval
*/
- addik r3,r7,0
- beqi r3,3f
-1:
- lbu r4,r6,r0
- addik r6,r6,1
-2:
- sb r4,r5,r0
- addik r3,r3,-1
- bneid r3,1b
- addik r5,r5,1 /* delay slot */
+ beqid r7, 3f /* zero size is not likely */
+ andi r3, r7, 0x3 /* filter add count */
+ bneid r3, 4f /* if is odd value then byte copying */
+ or r3, r5, r6 /* find if is any to/from unaligned */
+ andi r3, r3, 0x3 /* mask unaligned */
+ bneid r3, 1f /* it is unaligned -> then jump */
+ or r3, r0, r0
+
+/* at least one 4 byte copy */
+5: lw r4, r6, r3
+6: sw r4, r5, r3
+ addik r7, r7, -4
+ bneid r7, 5b
+ addik r3, r3, 4
+ addik r3, r7, 0
+ rtsd r15, 8
+ nop
+4: or r3, r0, r0
+1: lbu r4,r6,r3
+2: sb r4,r5,r3
+ addik r7,r7,-1
+ bneid r7,1b
+ addik r3,r3,1 /* delay slot */
3:
+ addik r3,r7,0
rtsd r15,8
nop
.size __copy_tofrom_user, . - __copy_tofrom_user
-
.section __ex_table,"a"
- .word 1b,3b,2b,3b
+ .word 1b,3b,2b,3b,5b,3b,6b,3b