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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/c6x/lib/mpyll.S
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/c6x/lib/mpyll.S')
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diff --git a/kernel/arch/c6x/lib/mpyll.S b/kernel/arch/c6x/lib/mpyll.S
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+;; 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)