diff options
Diffstat (limited to 'arch/hexagon/mm/copy_to_user.S')
| -rw-r--r-- | arch/hexagon/mm/copy_to_user.S | 79 |
1 files changed, 79 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 000000000..ed8e3cafb --- /dev/null +++ b/arch/hexagon/mm/copy_to_user.S @@ -0,0 +1,79 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * User memory copying routines for the Hexagon Kernel + * + * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved. + */ + +/* 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 raw_copy_to_user +#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 |