gbasys

view src/dma.c @ 12:a6ddf338a111

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author John Tsiombikas <nuclear@member.fsf.org>
date Mon, 01 Feb 2016 04:41:27 +0200
parents c50064b181c2
children
line source
1 /*
2 gbasys - a gameboy advance hardware abstraction library
3 Copyright (C) 2004-2014 John Tsiombikas <nuclear@member.fsf.org>
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18 #include "config.h"
19 #include "dma.h"
21 /* DMA Options */
22 #define DMA_ENABLE 0x80000000
23 #define DMA_INT_ENABLE 0x40000000
24 #define DMA_TIMING_IMMED 0x00000000
25 #define DMA_TIMING_VBLANK 0x10000000
26 #define DMA_TIMING_HBLANK 0x20000000
27 #define DMA_TIMING_DISPSYNC 0x30000000
28 #define DMA_16 0x00000000
29 #define DMA_32 0x04000000
30 #define DMA_REPEAT 0x02000000
31 #define DMA_SRC_INC 0x00000000
32 #define DMA_SRC_DEC 0x00800000
33 #define DMA_SRC_FIX 0x01000000
34 #define DMA_DST_INC 0x00000000
35 #define DMA_DST_DEC 0x00200000
36 #define DMA_DST_FIX1 0x00400000
37 #define DMA_DST_RELOAD 0x00600000
39 /* DMA Register Parts */
40 #define DMA_SRC 0
41 #define DMA_DST 1
42 #define DMA_CTRL 2
44 static volatile unsigned long *reg_dma[4] = {(void*)0x040000b0, (void*)0x040000bc, (void*)0x040000c8, (void*)0x040000d4 };
46 /* --- perform a copy of words or halfwords using DMA --- */
48 void dma_copy32(int channel, void *dst, void *src, int words)
49 {
50 reg_dma[channel][DMA_SRC] = (unsigned long)src;
51 reg_dma[channel][DMA_DST] = (unsigned long)dst;
52 reg_dma[channel][DMA_CTRL] = words | DMA_TIMING_IMMED | DMA_32 | DMA_ENABLE;
53 }
55 void dma_copy16(int channel, void *dst, void *src, int halfwords)
56 {
57 reg_dma[channel][DMA_SRC] = (unsigned long)src;
58 reg_dma[channel][DMA_DST] = (unsigned long)dst;
59 reg_dma[channel][DMA_CTRL] = halfwords | DMA_TIMING_IMMED | DMA_16 | DMA_ENABLE;
60 }
62 /* --- fill a buffer with an ammount of words and halfwords using DMA --- */
64 void dma_fill32(int channel, void *dst, unsigned long val, int words)
65 {
66 unsigned long valmem = val;
67 reg_dma[channel][DMA_SRC] = (unsigned long)&valmem;
68 reg_dma[channel][DMA_DST] = (unsigned long)dst;
69 reg_dma[channel][DMA_CTRL] = words | DMA_SRC_FIX | DMA_TIMING_IMMED | DMA_32 | DMA_ENABLE;
70 }
72 void dma_fill16(int channel, void *dst, unsigned short val, int halfwords)
73 {
74 unsigned short valmem = val;
75 reg_dma[channel][DMA_SRC] = (unsigned long)&valmem;
76 reg_dma[channel][DMA_DST] = (unsigned long)dst;
77 reg_dma[channel][DMA_CTRL] = halfwords | DMA_SRC_FIX | DMA_TIMING_IMMED | DMA_16 | DMA_ENABLE;
78 }