aboutsummaryrefslogtreecommitdiff
path: root/arch/alpha/lib/csum_ipv6_magic.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/alpha/lib/csum_ipv6_magic.S')
-rw-r--r--arch/alpha/lib/csum_ipv6_magic.S92
1 files changed, 92 insertions, 0 deletions
diff --git a/arch/alpha/lib/csum_ipv6_magic.S b/arch/alpha/lib/csum_ipv6_magic.S
new file mode 100644
index 00000000000..e09748dbf2e
--- /dev/null
+++ b/arch/alpha/lib/csum_ipv6_magic.S
@@ -0,0 +1,92 @@
+/*
+ * arch/alpha/lib/csum_ipv6_magic.S
+ * Contributed by Richard Henderson <rth@tamu.edu>
+ *
+ * unsigned short csum_ipv6_magic(struct in6_addr *saddr,
+ * struct in6_addr *daddr,
+ * __u32 len,
+ * unsigned short proto,
+ * unsigned int csum);
+ */
+
+ .globl csum_ipv6_magic
+ .align 4
+ .ent csum_ipv6_magic
+ .frame $30,0,$26,0
+csum_ipv6_magic:
+ .prologue 0
+
+ ldq $0,0($16) # e0 : load src & dst addr words
+ zapnot $20,15,$20 # .. e1 : zero extend incoming csum
+ extqh $18,1,$4 # e0 : byte swap len & proto while we wait
+ ldq $1,8($16) # .. e1 :
+
+ extbl $18,1,$5 # e0 :
+ ldq $2,0($17) # .. e1 :
+ extbl $18,2,$6 # e0 :
+ ldq $3,8($17) # .. e1 :
+
+ extbl $18,3,$18 # e0 :
+ sra $4,32,$4 # e0 :
+ sll $5,16,$5 # e0 :
+ addq $20,$0,$20 # .. e1 : begin summing the words
+
+ sll $6,8,$6 # e0 :
+ cmpult $20,$0,$0 # .. e1 :
+ extwh $19,7,$7 # e0 :
+ or $4,$18,$18 # .. e1 :
+
+ extbl $19,1,$19 # e0 :
+ or $5,$6,$5 # .. e1 :
+ or $18,$5,$18 # e0 : len complete
+ or $19,$7,$19 # .. e1 :
+
+ sll $19,48,$19 # e0 :
+ addq $20,$1,$20 # .. e1 :
+ sra $19,32,$19 # e0 : proto complete
+ cmpult $20,$1,$1 # .. e1 :
+
+ nop # e0 :
+ addq $20,$2,$20 # .. e1 :
+ cmpult $20,$2,$2 # e0 :
+ addq $20,$3,$20 # .. e1 :
+
+ cmpult $20,$3,$3 # e0 :
+ addq $20,$18,$20 # .. e1 :
+ cmpult $20,$18,$18 # e0 :
+ addq $20,$19,$20 # .. e1 :
+
+ cmpult $20,$19,$19 # e0 :
+ addq $0,$1,$0 # .. e1 : merge the carries back into the csum
+ addq $2,$3,$2 # e0 :
+ addq $18,$19,$18 # .. e1 :
+
+ addq $0,$2,$0 # e0 :
+ addq $20,$18,$20 # .. e1 :
+ addq $0,$20,$0 # e0 :
+ unop # :
+
+ extwl $0,2,$2 # e0 : begin folding the 64-bit value
+ zapnot $0,3,$3 # .. e1 :
+ extwl $0,4,$1 # e0 :
+ addq $2,$3,$3 # .. e1 :
+
+ extwl $0,6,$0 # e0 :
+ addq $3,$1,$3 # .. e1 :
+ addq $0,$3,$0 # e0 :
+ unop # :
+
+ extwl $0,2,$1 # e0 : fold 18-bit value
+ zapnot $0,3,$0 # .. e1 :
+ addq $0,$1,$0 # e0 :
+ unop # :
+
+ extwl $0,2,$1 # e0 : fold 17-bit value
+ zapnot $0,3,$0 # .. e1 :
+ addq $0,$1,$0 # e0 :
+ not $0,$0 # e1 : and complement.
+
+ zapnot $0,3,$0 # e0 :
+ ret # .. e1 :
+
+ .end csum_ipv6_magic