93 строки
2.1 KiB
ArmAsm
93 строки
2.1 KiB
ArmAsm
/*
|
|
* 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
|