Bryan Wu | 1394f03 | 2007-05-06 14:50:22 -0700 | [diff] [blame] | 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. |