1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * User memory copying routines for the Hexagon Kernel |
4 | * |
5 | * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved. |
6 | */ |
7 | |
8 | /* The right way to do this involves valignb |
9 | * The easy way to do this is only speed up src/dest similar alignment. |
10 | */ |
11 | |
12 | /* |
13 | * Copy to/from user are the same, except that for packets with a load and |
14 | * a store, I don't know how to tell which kind of exception we got. |
15 | * Therefore, we duplicate the function, and handle faulting addresses |
16 | * differently for each function |
17 | */ |
18 | |
19 | /* |
20 | * copy to user: stores can fault |
21 | */ |
22 | #define src_sav r13 |
23 | #define dst_sav r12 |
24 | #define src_dst_sav r13:12 |
25 | #define d_dbuf r15:14 |
26 | #define w_dbuf r15 |
27 | |
28 | #define dst r0 |
29 | #define src r1 |
30 | #define bytes r2 |
31 | #define loopcount r5 |
32 | |
33 | #define FUNCNAME raw_copy_to_user |
34 | #include "copy_user_template.S" |
35 | |
36 | /* STORE FAULTS from COPY_TO_USER */ |
37 | .falign |
38 | 1109: |
39 | 2109: |
40 | 4109: |
41 | /* Alignment loop. r2 has been updated. Return it. */ |
42 | { |
43 | r0 = r2 |
44 | jumpr r31 |
45 | } |
46 | /* Normal copy loops. Use dst-dst_sav to compute distance */ |
47 | /* dst holds best write, no need to unwind any loops */ |
48 | /* X - (A - B) == X + B - A */ |
49 | .falign |
50 | 8189: |
51 | 8199: |
52 | 4189: |
53 | 4199: |
54 | 2189: |
55 | 2199: |
56 | 1189: |
57 | 1199: |
58 | { |
59 | r2 += sub(dst_sav,dst) |
60 | } |
61 | { |
62 | r0 = r2 |
63 | jumpr r31 |
64 | } |
65 | |
66 | /* COPY TO USER: only stores can fail */ |
67 | .section __ex_table,"a" |
68 | .long 1100b,1109b |
69 | .long 2100b,2109b |
70 | .long 4100b,4109b |
71 | .long 8180b,8189b |
72 | .long 8190b,8199b |
73 | .long 4180b,4189b |
74 | .long 4190b,4199b |
75 | .long 2180b,2189b |
76 | .long 2190b,2199b |
77 | .long 1180b,1189b |
78 | .long 1190b,1199b |
79 | .previous |
80 | |