more SVP work
[picodrive.git] / Pico / carthw / svp / svp.c
1 #include "../../PicoInt.h"
2
3 svp_t *svp = NULL;
4
5 static void PicoSVPReset(void)
6 {
7         elprintf(EL_SVP, "SVP reset");
8
9         memcpy(svp->iram_rom + 0x800, Pico.rom + 0x800, 0x20000 - 0x800);
10         ssp1601_reset(&svp->ssp1601);
11 }
12
13
14 static void PicoSVPLine(void)
15 {
16         // ???
17         // OSC_NTSC / 3.0 / 60.0 / 262.0 ~= 1139
18         // OSC_PAL  / 3.0 / 50.0 / 312.0 ~= 1137
19         ssp1601_run(100);
20 }
21
22
23 static int PicoSVPDma(unsigned int source, int len, unsigned short **srcp, unsigned short **limitp)
24 {
25         if ((source & 0xfe0000) == 0x300000)
26         {
27                 elprintf(EL_VDPDMA|EL_SVP, "SVP DmaSlow from %06x, len=%i", source, len);
28                 source &= 0x1fffe;
29                 *srcp = (unsigned short *)(svp->dram + source);
30                 *limitp = (unsigned short *)(svp->dram + sizeof(svp->dram));
31                 return 1;
32         }
33
34         return 0;
35 }
36
37
38 void PicoSVPInit(void)
39 {
40         void *tmp;
41
42         elprintf(EL_SVP, "SVP init");
43
44         tmp = realloc(Pico.rom, 0x200000 + sizeof(*svp));
45         if (tmp == NULL)
46         {
47                 elprintf(EL_STATUS|EL_SVP, "OOM for SVP data");
48                 return;
49         }
50
51         Pico.rom = tmp;
52         svp = (void *) ((char *)tmp + 0x200000);
53         memset(svp, 0, sizeof(*svp));
54
55         // init ok, setup hooks..
56         PicoRead16Hook = PicoSVPRead16;
57         PicoWrite8Hook = PicoSVPWrite8;
58         PicoWrite16Hook = PicoSVPWrite16;
59         PicoDmaHook = PicoSVPDma;
60         PicoResetHook = PicoSVPReset;
61         PicoLineHook = PicoSVPLine;
62 }
63