/* * User memory copying routines for the Hexagon Kernel * * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 and * only version 2 as published by the Free Software Foundation. * * 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., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA. */ /* The right way to do this involves valignb * The easy way to do this is only speed up src/dest similar alignment. */ /* * Copy to/from user are the same, except that for packets with a load and * a store, I don't know how to tell which kind of exception we got. * Therefore, we duplicate the function, and handle faulting addresses * differently for each function */ /* * copy to user: stores can fault */ #define src_sav r13 #define dst_sav r12 #define src_dst_sav r13:12 #define d_dbuf r15:14 #define w_dbuf r15 #define dst r0 #define src r1 #define bytes r2 #define loopcount r5 #define FUNCNAME __copy_to_user_hexagon #include "copy_user_template.S" /* STORE FAULTS from COPY_TO_USER */ .falign 1109: 2109: 4109: /* Alignment loop. r2 has been updated. Return it. */ { r0 = r2 jumpr r31 } /* Normal copy loops. Use dst-dst_sav to compute distance */ /* dst holds best write, no need to unwind any loops */ /* X - (A - B) == X + B - A */ .falign 8189: 8199: 4189: 4199: 2189: 2199: 1189: 1199: { r2 += sub(dst_sav,dst) } { r0 = r2 jumpr r31 } /* COPY TO USER: only stores can fail */ .section __ex_table,"a" .long 1100b,1109b .long 2100b,2109b .long 4100b,4109b .long 8180b,8189b .long 8190b,8199b .long 4180b,4189b .long 4190b,4199b .long 2180b,2189b .long 2190b,2199b .long 1180b,1189b .long 1190b,1199b .previous