diff options
Diffstat (limited to 'Documentation/blackfin/cache-lock.txt')
-rw-r--r-- | Documentation/blackfin/cache-lock.txt | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/Documentation/blackfin/cache-lock.txt b/Documentation/blackfin/cache-lock.txt new file mode 100644 index 000000000000..88ba1e6c31c3 --- /dev/null +++ b/Documentation/blackfin/cache-lock.txt | |||
@@ -0,0 +1,48 @@ | |||
1 | /* | ||
2 | * File: Documentation/blackfin/cache-lock.txt | ||
3 | * Based on: | ||
4 | * Author: | ||
5 | * | ||
6 | * Created: | ||
7 | * Description: This file contains the simple DMA Implementation for Blackfin | ||
8 | * | ||
9 | * Rev: $Id: cache-lock.txt 2384 2006-11-01 04:12:43Z magicyang $ | ||
10 | * | ||
11 | * Modified: | ||
12 | * Copyright 2004-2006 Analog Devices Inc. | ||
13 | * | ||
14 | * Bugs: Enter bugs at http://blackfin.uclinux.org/ | ||
15 | * | ||
16 | */ | ||
17 | |||
18 | How to lock your code in cache in uClinux/blackfin | ||
19 | -------------------------------------------------- | ||
20 | |||
21 | There are only a few steps required to lock your code into the cache. | ||
22 | Currently you can lock the code by Way. | ||
23 | |||
24 | Below are the interface provided for locking the cache. | ||
25 | |||
26 | |||
27 | 1. cache_grab_lock(int Ways); | ||
28 | |||
29 | This function grab the lock for locking your code into the cache specified | ||
30 | by Ways. | ||
31 | |||
32 | |||
33 | 2. cache_lock(int Ways); | ||
34 | |||
35 | This function should be called after your critical code has been executed. | ||
36 | Once the critical code exits, the code is now loaded into the cache. This | ||
37 | function locks the code into the cache. | ||
38 | |||
39 | |||
40 | So, the example sequence will be: | ||
41 | |||
42 | cache_grab_lock(WAY0_L); /* Grab the lock */ | ||
43 | |||
44 | critical_code(); /* Execute the code of interest */ | ||
45 | |||
46 | cache_lock(WAY0_L); /* Lock the cache */ | ||
47 | |||
48 | Where WAY0_L signifies WAY0 locking. | ||