;; Copyright (C) 2010 Texas Instruments Incorporated ;; Contributed by Mark Salter <msalter@redhat.com>. ;; ;; This program is free software; you can redistribute it and/or modify ;; it under the terms of the GNU General Public License as published by ;; the Free Software Foundation; either version 2 of the License, or ;; (at your option) any later version. ;; ;; This program is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;; GNU General Public License for more details. ;; ;; You should have received a copy of the GNU General Public License ;; along with this program; if not, write to the Free Software ;; Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. #include <linux/linkage.h> ;; uint64_t __c6xabi_mpyll(uint64_t x, uint64_t y) ;; ;; 64x64 multiply ;; First compute partial results using 32-bit parts of x and y: ;; ;; b63 b32 b31 b0 ;; ----------------------------- ;; | 1 | 0 | ;; ----------------------------- ;; ;; P0 = X0*Y0 ;; P1 = X0*Y1 + X1*Y0 ;; P2 = X1*Y1 ;; ;; result = (P2 << 64) + (P1 << 32) + P0 ;; ;; Since the result is also 64-bit, we can skip the P2 term. .text ENTRY(__c6xabi_mpyll) mpy32u .m1x A4,B4,A1:A0 ; X0*Y0 b .s2 B3 || mpy32u .m2x B5,A4,B1:B0 ; X0*Y1 (don't need upper 32-bits) || mpy32u .m1x A5,B4,A3:A2 ; X1*Y0 (don't need upper 32-bits) nop nop mv .s1 A0,A4 add .l1x A2,B0,A5 add .s1 A1,A5,A5 ENDPROC(__c6xabi_mpyll)