dma: try more accurate timings

[pcsx_rearmed.git] / libpcsxcore / mdec.c

diff --git a/libpcsxcore/mdec.c b/libpcsxcore/mdec.c
index 61ed5ea..4b93ffa 100644 (file)
--- a/libpcsxcore/mdec.c
+++ b/libpcsxcore/mdec.c
@@ -33,12 +33,10 @@
  * so 2.0 to 4.0 should be fine.
  */
  
-/* Was set to 2 before but it would cause issues in R-types and Vandal Hearts videos. 
- * Setting it to 6 as dmitrysmagin did fix those... except for Galerians.
- * Galerians needs this to be set to 10 (!!) before it looks properly.
- * I've tried this with a few other games (including R-Types) and so far, this
- * has not backfired.
- * */
+/*
+ * >= 10 for Galerians
+ * <= 18 for "Disney's Treasure Planet"
+ */
 #define MDEC_BIAS 10
 
 #define DSIZE                  8
@@ -487,7 +485,7 @@ void psxDma0(u32 adr, u32 bcr, u32 chcr) {
        size = (bcr >> 16) * (bcr & 0xffff);
 
        switch (cmd >> 28) {
-               case 0x3: // decode
+               case 0x3: // decode 15/24bpp
                        mdec.rl = (u16 *) PSXM(adr);
                        /* now the mdec is busy till all data are decoded */
                        mdec.reg1 |= MDEC1_BUSY;
@@ -495,10 +493,8 @@ void psxDma0(u32 adr, u32 bcr, u32 chcr) {
                        mdec.rl_end = mdec.rl + (size * 2);
 
                        /* sanity check */
-                       if(mdec.rl_end <= mdec.rl) {
-                               MDECINDMA_INT( size / 4 );
-                               return;
-                       }
+                       if(mdec.rl_end <= mdec.rl)
+                               break;
 
                        /* process the pending dma1 */
                        if(mdec.pending_dma1.adr){
@@ -517,23 +513,18 @@ void psxDma0(u32 adr, u32 bcr, u32 chcr) {
                                iqtab_init(iq_y, p);
                                iqtab_init(iq_uv, p + 64);
                        }
-
-                       MDECINDMA_INT( size / 4 );
-      return;
+                       break;
 
                case 0x6: // cosine table
                        // printf("mdec cosine table\n");
-
-                       MDECINDMA_INT( size / 4 );
-      return;
+                       break;
 
                default:
                        // printf("mdec unknown command\n");
                        break;
        }
 
-       HW_DMA0_CHCR &= SWAP32(~0x01000000);
-       DMA_INTERRUPT(0);
+       MDECINDMA_INT(size);
 }
 
 void mdec0Interrupt()
@@ -629,8 +620,10 @@ void psxDma1(u32 adr, u32 bcr, u32 chcr) {
                }
        }
        
-       /* define the power of mdec */
-       MDECOUTDMA_INT(words * MDEC_BIAS);
+               /* define the power of mdec */
+               MDECOUTDMA_INT(words * MDEC_BIAS);
+               /* some CPU stalling */
+               psxRegs.cycle += words;
        }
 }