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 "../../cpu/drc/cmn.h"
  11 #include "compiler.h"
  12
  13 svp_t *svp = NULL;
  14 int PicoSVPCycles = 850; // cycles/line, just a guess
  15 static int svp_dyn_ready = 0;
  16
  17 /* save state stuff */
  18 typedef enum {
  19         CHUNK_IRAM = CHUNK_CARTHW,
  20         CHUNK_DRAM,
  21         CHUNK_SSP
  22 } chunk_name_e;
  23
  24 static carthw_state_chunk svp_states[] =
  25 {
  26         { CHUNK_IRAM, 0x800,                 NULL },
  27         { CHUNK_DRAM, sizeof(svp->dram),     NULL },
  28         { CHUNK_SSP,  sizeof(svp->ssp1601) - sizeof(svp->ssp1601.drc),  NULL },
  29         { 0,          0,                     NULL }
  30 };
  31
  32
  33 static void PicoSVPReset(void)
  34 {
  35         elprintf(EL_SVP, "SVP reset");
  36
  37         memcpy(svp->iram_rom + 0x800, Pico.rom + 0x800, 0x20000 - 0x800);
  38         ssp1601_reset(&svp->ssp1601);
  39 #ifndef PSP
  40         if ((PicoOpt&POPT_EN_SVP_DRC) && svp_dyn_ready)
  41                 ssp1601_dyn_reset(&svp->ssp1601);
  42 #endif
  43 }
  44
  45
  46 static void PicoSVPLine(void)
  47 {
  48         int count = 1;
  49 #if defined(ARM) || defined(PSP)
  50         // performance hack
  51         static int delay_lines = 0;
  52         delay_lines++;
  53         if ((Pico.m.scanline&0xf) != 0xf && Pico.m.scanline != 261 && Pico.m.scanline != 311)
  54                 return;
  55         count = delay_lines;
  56         delay_lines = 0;
  57 #endif
  58
  59 #ifndef PSP
  60         if ((PicoOpt&POPT_EN_SVP_DRC) && svp_dyn_ready)
  61                 ssp1601_dyn_run(PicoSVPCycles * count);
  62         else
  63 #endif
  64         {
  65                 ssp1601_run(PicoSVPCycles * count);
  66                 svp_dyn_ready = 0; // just in case
  67         }
  68
  69         // test mode
  70         //if (Pico.m.frame_count == 13) PicoPad[0] |= 0xff;
  71 }
  72
  73
  74 static int PicoSVPDma(unsigned int source, int len, unsigned short **srcp, unsigned short **limitp)
  75 {
  76         if (source < Pico.romsize) // Rom
  77         {
  78                 source -= 2;
  79                 *srcp = (unsigned short *)(Pico.rom + (source&~1));
  80                 *limitp = (unsigned short *)(Pico.rom + Pico.romsize);
  81                 return 1;
  82         }
  83         else if ((source & 0xfe0000) == 0x300000)
  84         {
  85                 elprintf(EL_VDPDMA|EL_SVP, "SVP DmaSlow from %06x, len=%i", source, len);
  86                 source &= 0x1fffe;
  87                 source -= 2;
  88                 *srcp = (unsigned short *)(svp->dram + source);
  89                 *limitp = (unsigned short *)(svp->dram + sizeof(svp->dram));
  90                 return 1;
  91         }
  92         else
  93                 elprintf(EL_VDPDMA|EL_SVP|EL_ANOMALY, "SVP FIXME unhandled DmaSlow from %06x, len=%i", source, len);
  94
  95         return 0;
  96 }
  97
  98
  99 void PicoSVPInit(void)
 100 {
 101 #ifndef PSP
 102         // this is to unmap tcache and make
 103         // mem available for large ROMs, MCD, etc.
 104         drc_cmn_cleanup();
 105 #endif
 106 }
 107
 108 static void PicoSVPExit(void)
 109 {
 110 #ifndef PSP
 111         ssp1601_dyn_exit();
 112 #endif
 113 }
 114
 115
 116 void PicoSVPStartup(void)
 117 {
 118         int ret;
 119
 120         elprintf(EL_STATUS, "SVP startup");
 121
 122         ret = PicoCartResize(Pico.romsize + sizeof(*svp));
 123         if (ret != 0) {
 124                 elprintf(EL_STATUS|EL_SVP, "OOM for SVP data");
 125                 return;
 126         }
 127
 128         svp = (void *) ((char *)Pico.rom + Pico.romsize);
 129         memset(svp, 0, sizeof(*svp));
 130
 131         // init SVP compiler
 132         svp_dyn_ready = 0;
 133 #ifndef PSP
 134         if (PicoOpt & POPT_EN_SVP_DRC) {
 135                 if (ssp1601_dyn_startup())
 136                         return;
 137                 svp_dyn_ready = 1;
 138         }
 139 #endif
 140
 141         // init ok, setup hooks..
 142         PicoCartMemSetup = PicoSVPMemSetup;
 143         PicoDmaHook = PicoSVPDma;
 144         PicoResetHook = PicoSVPReset;
 145         PicoLineHook = PicoSVPLine;
 146         PicoCartUnloadHook = PicoSVPExit;
 147
 148         // save state stuff
 149         svp_states[0].ptr = svp->iram_rom;
 150         svp_states[1].ptr = svp->dram;
 151         svp_states[2].ptr = &svp->ssp1601;
 152         carthw_chunks = svp_states;
 153         PicoAHW |= PAHW_SVP;
 154 }
 155