1 ;; SPDX-License-Identifier: GPL-2.0-or-later
2 ;;  Copyright (C) 2010 Texas Instruments Incorporated
3 ;;  Contributed by Mark Salter <msalter@redhat.com>.
4 ;;
5 
6 #include <linux/linkage.h>
7 
8 	;; uint64_t __c6xabi_mpyll(uint64_t x, uint64_t y)
9 	;;
10 	;; 64x64 multiply
11 	;; First compute partial results using 32-bit parts of x and y:
12 	;;
13 	;;   b63	 b32 b31	  b0
14 	;;    -----------------------------
15 	;;    |      1	    |	   0	  |
16 	;;    -----------------------------
17 	;;
18 	;;   P0 = X0*Y0
19 	;;   P1 = X0*Y1 + X1*Y0
20 	;;   P2 = X1*Y1
21 	;;
22 	;;   result = (P2 << 64) + (P1 << 32) + P0
23 	;;
24 	;; Since the result is also 64-bit, we can skip the P2 term.
25 
26 	.text
27 ENTRY(__c6xabi_mpyll)
28 	mpy32u	.m1x	A4,B4,A1:A0	; X0*Y0
29 	b	.s2	B3
30  ||	mpy32u	.m2x	B5,A4,B1:B0	; X0*Y1 (don't need upper 32-bits)
31  ||	mpy32u	.m1x	A5,B4,A3:A2	; X1*Y0 (don't need upper 32-bits)
32 	nop
33 	nop
34 	mv	.s1	A0,A4
35 	add	.l1x	A2,B0,A5
36 	add	.s1	A1,A5,A5
37 ENDPROC(__c6xabi_mpyll)
38