pico/carthw/svp/svp.c

   1 // The SVP chip emulator
   2
   3 // (c) Copyright 2008, Grazvydas "notaz" Ignotas
   4 // Free for non-commercial use.
   5
   6 // For commercial use, separate licencing terms must be obtained.
   7
   8
   9 #include "../../pico_int.h"
  10 #include "compiler.h"
  11
  12 svp_t *svp = NULL;
  13 int PicoSVPCycles = 850; // cycles/line, just a guess
  14 static int svp_dyn_ready = 0;
  15
  16 /* save state stuff */
  17 typedef enum {
  18         CHUNK_IRAM = CHUNK_CARTHW,
  19         CHUNK_DRAM,
  20         CHUNK_SSP
  21 } chunk_name_e;
  22
  23 static carthw_state_chunk svp_states[] =
  24 {
  25         { CHUNK_IRAM, 0x800,                 NULL },
  26         { CHUNK_DRAM, sizeof(svp->dram),     NULL },
  27         { CHUNK_SSP,  sizeof(svp->ssp1601) - sizeof(svp->ssp1601.drc),  NULL },
  28         { 0,          0,                     NULL }
  29 };
  30
  31
  32 static void PicoSVPReset(void)
  33 {
  34         elprintf(EL_SVP, "SVP reset");
  35
  36         memcpy(svp->iram_rom + 0x800, Pico.rom + 0x800, 0x20000 - 0x800);
  37         ssp1601_reset(&svp->ssp1601);
  38 #ifndef PSP
  39         if ((PicoOpt&POPT_EN_SVP_DRC) && svp_dyn_ready)
  40                 ssp1601_dyn_reset(&svp->ssp1601);
  41 #endif
  42 }
  43
  44
  45 static void PicoSVPLine(void)
  46 {
  47         int count = 1;
  48 #if defined(ARM) || defined(PSP)
  49         // performance hack
  50         static int delay_lines = 0;
  51         delay_lines++;
  52         if ((Pico.m.scanline&0xf) != 0xf && Pico.m.scanline != 261 && Pico.m.scanline != 311)
  53                 return;
  54         count = delay_lines;
  55         delay_lines = 0;
  56 #endif
  57
  58 #ifndef PSP
  59         if ((PicoOpt&POPT_EN_SVP_DRC) && svp_dyn_ready)
  60                 ssp1601_dyn_run(PicoSVPCycles * count);
  61         else
  62 #endif
  63         {
  64                 ssp1601_run(PicoSVPCycles * count);
  65                 svp_dyn_ready = 0; // just in case
  66         }
  67
  68         // test mode
  69         //if (Pico.m.frame_count == 13) PicoPad[0] |= 0xff;
  70 }
  71
  72
  73 static int PicoSVPDma(unsigned int source, int len, unsigned short **srcp, unsigned short **limitp)
  74 {
  75         if (source < Pico.romsize) // Rom
  76         {
  77                 source -= 2;
  78                 *srcp = (unsigned short *)(Pico.rom + (source&~1));
  79                 *limitp = (unsigned short *)(Pico.rom + Pico.romsize);
  80                 return 1;
  81         }
  82         else if ((source & 0xfe0000) == 0x300000)
  83         {
  84                 elprintf(EL_VDPDMA|EL_SVP, "SVP DmaSlow from %06x, len=%i", source, len);
  85                 source &= 0x1fffe;
  86                 source -= 2;
  87                 *srcp = (unsigned short *)(svp->dram + source);
  88                 *limitp = (unsigned short *)(svp->dram + sizeof(svp->dram));
  89                 return 1;
  90         }
  91         else
  92                 elprintf(EL_VDPDMA|EL_SVP|EL_ANOMALY, "SVP FIXME unhandled DmaSlow from %06x, len=%i", source, len);
  93
  94         return 0;
  95 }
  96
  97
  98 void PicoSVPInit(void)
  99 {
 100 }
 101
 102
 103 void PicoSVPStartup(void)
 104 {
 105         void *tmp;
 106
 107         elprintf(EL_STATUS, "SVP startup");
 108
 109         tmp = realloc(Pico.rom, 0x200000 + sizeof(*svp));
 110         if (tmp == NULL)
 111         {
 112                 elprintf(EL_STATUS|EL_SVP, "OOM for SVP data");
 113                 return;
 114         }
 115
 116         //PicoOpt &= ~0x20000;
 117         Pico.rom = tmp;
 118         svp = (void *) ((char *)tmp + 0x200000);
 119         memset(svp, 0, sizeof(*svp));
 120
 121         // init SVP compiler
 122         svp_dyn_ready = 0;
 123 #ifndef PSP
 124         if (PicoOpt & POPT_EN_SVP_DRC) {
 125                 if (ssp1601_dyn_startup())
 126                         return;
 127                 svp_dyn_ready = 1;
 128         }
 129 #endif
 130
 131         // init ok, setup hooks..
 132         PicoCartMemSetup = PicoSVPMemSetup;
 133         PicoDmaHook = PicoSVPDma;
 134         PicoResetHook = PicoSVPReset;
 135         PicoLineHook = PicoSVPLine;
 136
 137         // save state stuff
 138         svp_states[0].ptr = svp->iram_rom;
 139         svp_states[1].ptr = svp->dram;
 140         svp_states[2].ptr = &svp->ssp1601;
 141         carthw_chunks = svp_states;
 142         PicoAHW |= PAHW_SVP;
 143 }
 144
 145