1 /*

2 Copyright 2004 John Tsiombikas <nuclear@siggraph.org>

3

4 This file is part of libgba, a library for GameBoy Advance development.

5

6 This program is free software; you can redistribute it and/or modify

7 it under the terms of the GNU General Public License as published by

8 the Free Software Foundation; either version 2 of the License, or

9 (at your option) any later version.

10

11 This program is distributed in the hope that it will be useful,

12 but WITHOUT ANY WARRANTY; without even the implied warranty of

13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

14 GNU General Public License for more details.

15

16 You should have received a copy of the GNU General Public License

17 along with this program; if not, write to the Free Software

18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

19 */

20

21 #include "libgba_config.h"

22 #include "dma.h"

23

24 /* DMA Options */

25 #define DMA_ENABLE 0x80000000

26 #define DMA_INT_ENABLE 0x40000000

27 #define DMA_TIMING_IMMED 0x00000000

28 #define DMA_TIMING_VBLANK 0x10000000

29 #define DMA_TIMING_HBLANK 0x20000000

30 #define DMA_TIMING_DISPSYNC 0x30000000

31 #define DMA_16 0x00000000

32 #define DMA_32 0x04000000

33 #define DMA_REPEAT 0x02000000

34 #define DMA_SRC_INC 0x00000000

35 #define DMA_SRC_DEC 0x00800000

36 #define DMA_SRC_FIX 0x01000000

37 #define DMA_DST_INC 0x00000000

38 #define DMA_DST_DEC 0x00200000

39 #define DMA_DST_FIX1 0x00400000

40 #define DMA_DST_RELOAD 0x00600000

41

42 /* DMA Register Parts */

43 #define DMA_SRC 0

44 #define DMA_DST 1

45 #define DMA_CTRL 2

46

47 static volatile unsigned long *reg_dma[4] = {(void*)0x040000b0, (void*)0x040000bc, (void*)0x040000c8, (void*)0x040000d4 };

48

49 /* --- perform a copy of words or halfwords using DMA --- */

50

51 void dma_copy32(int channel, void *dst, void *src, int words) {

52 reg_dma[channel][DMA_SRC] = (unsigned long)src;

53 reg_dma[channel][DMA_DST] = (unsigned long)dst;

54 reg_dma[channel][DMA_CTRL] = words | DMA_TIMING_IMMED | DMA_32 | DMA_ENABLE;

55 }

56

57 void dma_copy16(int channel, void *dst, void *src, int halfwords) {

58 reg_dma[channel][DMA_SRC] = (unsigned long)src;

59 reg_dma[channel][DMA_DST] = (unsigned long)dst;

60 reg_dma[channel][DMA_CTRL] = halfwords | DMA_TIMING_IMMED | DMA_16 | DMA_ENABLE;

61 }

62

63 /* --- fill a buffer with an ammount of words and halfwords using DMA --- */

64

65 void dma_fill32(int channel, void *dst, unsigned long val, int words) {

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 }

71

72 void dma_fill16(int channel, void *dst, unsigned short val, int halfwords) {

73 unsigned short valmem = val;

74 reg_dma[channel][DMA_SRC] = (unsigned long)&valmem;

75 reg_dma[channel][DMA_DST] = (unsigned long)dst;

76 reg_dma[channel][DMA_CTRL] = halfwords | DMA_SRC_FIX | DMA_TIMING_IMMED | DMA_16 | DMA_ENABLE;

77 }