diff options
Diffstat (limited to 'arch/hexagon/mm/copy_to_user.S')
| -rw-r--r-- | arch/hexagon/mm/copy_to_user.S | 92 | 
1 files changed, 92 insertions, 0 deletions
diff --git a/arch/hexagon/mm/copy_to_user.S b/arch/hexagon/mm/copy_to_user.S new file mode 100644 index 00000000000..0cfbcc09d1d --- /dev/null +++ b/arch/hexagon/mm/copy_to_user.S @@ -0,0 +1,92 @@ +/* + * User memory copying routines for the Hexagon Kernel + * + * Copyright (c) 2010-2011, The Linux Foundation. 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  | 
