implementation of VRAM and other misc crap

1 files changed, 695 insertions, 1 deletions

diff --git a/GPU2D.cpp b/GPU2D.cpp
index 8145101..a879576 100644
--- a/GPU2D.cpp
+++ b/GPU2D.cpp
@@ -16,6 +16,8 @@
     with melonDS. If not, see http://www.gnu.org/licenses/.
 */
 
+#include <stdio.h>
+#include <string.h>
 #include "NDS.h"
 #include "GPU2D.h"
 
@@ -23,6 +25,698 @@
 namespace GPU2D
 {
 
-//
+#define LINE_CYCLES  (355*6 * 2)
+#define FRAME_CYCLES  (LINE_CYCLES * 263)
+
+u16 VCount;
+
+u16 DispStat[2], VMatch[2];
+
+u8 VRAM_A[128*1024];
+u8 VRAM_B[128*1024];
+u8 VRAM_C[128*1024];
+u8 VRAM_D[128*1024];
+u8 VRAM_E[ 64*1024];
+u8 VRAM_F[ 16*1024];
+u8 VRAM_G[ 16*1024];
+u8 VRAM_H[ 32*1024];
+u8 VRAM_I[ 16*1024];
+u8* VRAM[9] = {VRAM_A, VRAM_B, VRAM_C, VRAM_D, VRAM_E, VRAM_F, VRAM_G, VRAM_H, VRAM_I};
+
+u8 VRAMCNT[9];
+u8 VRAMSTAT;
+
+u8* VRAM_ABG[128];
+u8* VRAM_AOBJ[128];
+u8* VRAM_BBG[128];
+u8* VRAM_BOBJ[128];
+u8* VRAM_LCD[128];
+u8* VRAM_ARM7[2];
+
+
+void Reset()
+{
+    VCount = 0;
+
+    DispStat[0] = 0;
+    DispStat[1] = 0;
+    VMatch[0] = 0;
+    VMatch[1] = 0;
+
+    memset(VRAM_A, 0, 128*1024);
+    memset(VRAM_B, 0, 128*1024);
+    memset(VRAM_C, 0, 128*1024);
+    memset(VRAM_D, 0, 128*1024);
+    memset(VRAM_E, 0,  64*1024);
+    memset(VRAM_F, 0,  16*1024);
+    memset(VRAM_G, 0,  16*1024);
+    memset(VRAM_H, 0,  32*1024);
+    memset(VRAM_I, 0,  16*1024);
+
+    memset(VRAMCNT, 0, 9);
+    VRAMSTAT = 0;
+
+    memset(VRAM_ABG, 0, sizeof(u8*)*128);
+    memset(VRAM_AOBJ, 0, sizeof(u8*)*128);
+    memset(VRAM_BBG, 0, sizeof(u8*)*128);
+    memset(VRAM_BOBJ, 0, sizeof(u8*)*128);
+    memset(VRAM_LCD, 0, sizeof(u8*)*128);
+    memset(VRAM_ARM7, 0, sizeof(u8*)*2);
+}
+
+
+void MapVRAM_AB(u32 bank, u8 cnt)
+{
+    u8 oldcnt = VRAMCNT[bank];
+    VRAMCNT[bank] = cnt;
+
+    if (oldcnt == cnt) return;
+
+    u8 oldofs = (oldcnt >> 3) & 0x3;
+    u8 ofs = (cnt >> 3) & 0x3;
+
+    u8* vram = VRAM[bank];
+
+    if (oldcnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (oldcnt & 0x3)
+        {
+        case 0:
+            vrammap = &VRAM_LCD[bank<<3];
+            break;
+
+        case 1:
+            vrammap = &VRAM_ABG[oldofs<<3];
+            break;
+
+        case 2:
+            oldofs &= 0x1;
+            vrammap = &VRAM_AOBJ[oldofs<<3];
+            break;
+
+        case 3:
+            // not mapped to memory
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap   = NULL;
+        }
+    }
+
+    if (cnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (cnt & 0x3)
+        {
+        case 0:
+            vrammap = &VRAM_LCD[bank<<3];
+            break;
+
+        case 1:
+            vrammap = &VRAM_ABG[ofs<<3];
+            break;
+
+        case 2:
+            ofs &= 0x1;
+            vrammap = &VRAM_AOBJ[ofs<<3];
+            break;
+
+        case 3:
+            // not mapped to memory
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap   = vram;
+        }
+    }
+}
+
+void MapVRAM_CD(u32 bank, u8 cnt)
+{
+    u8 oldcnt = VRAMCNT[bank];
+    VRAMCNT[bank] = cnt;
+
+    VRAMSTAT &= ~(1 << (bank-2));
+
+    if (oldcnt == cnt) return;
+
+    u8 oldofs = (oldcnt >> 3) & 0x7;
+    u8 ofs = (cnt >> 3) & 0x7;
+
+    u8* vram = VRAM[bank];
+
+    if (oldcnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (oldcnt & 0x7)
+        {
+        case 0:
+            vrammap = &VRAM_LCD[bank<<3];
+            break;
+
+        case 1:
+            vrammap = &VRAM_ABG[oldofs<<3];
+            break;
+
+        case 2:
+            oldofs &= 0x1;
+            VRAM_ARM7[oldofs] = NULL;
+            break;
+
+        case 3:
+            // not mapped to memory
+            break;
+
+        case 4:
+            if (bank == 2)
+                vrammap = &VRAM_BBG[0];
+            else
+                vrammap = &VRAM_BOBJ[0];
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap   = NULL;
+        }
+    }
+
+    if (cnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (cnt & 0x7)
+        {
+        case 0:
+            vrammap = &VRAM_LCD[bank<<3];
+            break;
+
+        case 1:
+            vrammap = &VRAM_ABG[ofs<<3];
+            break;
+
+        case 2:
+            ofs &= 0x1;
+            VRAM_ARM7[ofs] = vram;
+            VRAMSTAT |= (1 << (bank-2));
+            break;
+
+        case 3:
+            // not mapped to memory
+            break;
+
+        case 4:
+            if (bank == 2)
+                vrammap = &VRAM_BBG[0];
+            else
+                vrammap = &VRAM_BOBJ[0];
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap++ = vram; vram += 0x4000;
+            *vrammap   = vram;
+        }
+    }
+}
+
+void MapVRAM_E(u32 bank, u8 cnt)
+{
+    u8 oldcnt = VRAMCNT[bank];
+    VRAMCNT[bank] = cnt;
+
+    if (oldcnt == cnt) return;
+
+    u8 oldofs = (oldcnt >> 3) & 0x7;
+    u8 ofs = (cnt >> 3) & 0x7;
+
+    u8* vram = VRAM[bank];
+
+    if (oldcnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (oldcnt & 0x7)
+        {
+        case 0:
+            VRAM_LCD[0x20] = NULL;
+            VRAM_LCD[0x21] = NULL;
+            VRAM_LCD[0x22] = NULL;
+            VRAM_LCD[0x23] = NULL;
+            break;
+
+        case 1:
+            vrammap = &VRAM_ABG[0];
+            break;
+
+        case 2:
+            vrammap = &VRAM_AOBJ[0];
+            break;
+
+        case 3:
+            // not mapped to memory
+            break;
+
+        case 4:
+            // BG EXTPAL -- TODO
+            break;
+
+        case 5:
+            // OBJ EXTPAL -- TODO
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap   = NULL;
+        }
+    }
+
+    if (cnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (cnt & 0x7)
+        {
+        case 0:
+            VRAM_LCD[0x20] = &vram[0x0000];
+            VRAM_LCD[0x21] = &vram[0x4000];
+            VRAM_LCD[0x22] = &vram[0x8000];
+            VRAM_LCD[0x23] = &vram[0xC000];
+            break;
+
+        case 1:
+            vrammap = &VRAM_ABG[0];
+            break;
+
+        case 2:
+            vrammap = &VRAM_AOBJ[0];
+            break;
+
+        case 3:
+            // not mapped to memory
+            break;
+
+        case 4:
+            // BG EXTPAL -- TODO
+            break;
+
+        case 5:
+            // OBJ EXTPAL -- TODO
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = &vram[0x0000];
+            *vrammap++ = &vram[0x4000];
+            *vrammap++ = &vram[0x8000];
+            *vrammap++ = &vram[0xC000];
+            *vrammap++ = &vram[0x0000];
+            *vrammap++ = &vram[0x4000];
+            *vrammap++ = &vram[0x8000];
+            *vrammap   = &vram[0xC000];
+        }
+    }
+}
+
+void MapVRAM_FG(u32 bank, u8 cnt)
+{
+    u8 oldcnt = VRAMCNT[bank];
+    VRAMCNT[bank] = cnt;
+
+    if (oldcnt == cnt) return;
+
+    u8 oldofs = (oldcnt >> 3) & 0x7;
+    u8 ofs = (cnt >> 3) & 0x7;
+
+    u8* vram = VRAM[bank];
+    bank -= 5;
+
+    if (oldcnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (oldcnt & 0x7)
+        {
+        case 0:
+            VRAM_LCD[0x24 + bank] = NULL;
+            break;
+
+        case 1:
+            vrammap = &VRAM_ABG[(oldofs & 0x1) | ((oldofs & 0x2) << 1)];
+            break;
+
+        case 2:
+            vrammap = &VRAM_AOBJ[(oldofs & 0x1) | ((oldofs & 0x2) << 1)];
+            break;
+
+        case 3:
+            // not mapped to memory
+            break;
+
+        case 4:
+            // BG EXTPAL TODO
+            break;
+
+        case 5:
+            // OBJ EXTPAL TODO
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap   = NULL;
+        }
+    }
+
+    if (cnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (cnt & 0x7)
+        {
+        case 0:
+            VRAM_LCD[0x24 + bank] = vram;
+            break;
+
+        case 1:
+            vrammap = &VRAM_ABG[(ofs & 0x1) | ((ofs & 0x2) << 1)];
+            break;
+
+        case 2:
+            vrammap = &VRAM_AOBJ[(ofs & 0x1) | ((ofs & 0x2) << 1)];
+            break;
+
+        case 3:
+            // not mapped to memory
+            break;
+
+        case 4:
+            // BG EXTPAL TODO
+            break;
+
+        case 5:
+            // OBJ EXTPAL TODO
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap   = vram;
+        }
+    }
+}
+
+void MapVRAM_H(u32 bank, u8 cnt)
+{
+    u8 oldcnt = VRAMCNT[bank];
+    VRAMCNT[bank] = cnt;
+
+    if (oldcnt == cnt) return;
+
+    u8 oldofs = (oldcnt >> 3) & 0x7;
+    u8 ofs = (cnt >> 3) & 0x7;
+
+    u8* vram = VRAM[bank];
+
+    if (oldcnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (oldcnt & 0x3)
+        {
+        case 0:
+            VRAM_LCD[0x26] = NULL;
+            VRAM_LCD[0x27] = NULL;
+            break;
+
+        case 1:
+            vrammap = &VRAM_BBG[0x00];
+            break;
+
+        case 2:
+            // BG EXTPAL TODO
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap   = NULL;
+        }
+    }
+
+    if (cnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (cnt & 0x3)
+        {
+        case 0:
+            VRAM_LCD[0x26] = &vram[0x0000];
+            VRAM_LCD[0x27] = &vram[0x4000];
+            break;
+
+        case 1:
+            vrammap = &VRAM_BBG[0x00];
+            break;
+
+        case 2:
+            // BG EXTPAL TODO
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = &vram[0x0000];
+            *vrammap++ = &vram[0x4000];
+            *vrammap++ = &vram[0x0000];
+            *vrammap++ = &vram[0x4000];
+            *vrammap++ = &vram[0x0000];
+            *vrammap++ = &vram[0x4000];
+            *vrammap++ = &vram[0x0000];
+            *vrammap   = &vram[0x4000];
+        }
+    }
+}
+
+void MapVRAM_I(u32 bank, u8 cnt)
+{
+    u8 oldcnt = VRAMCNT[bank];
+    VRAMCNT[bank] = cnt;
+
+    if (oldcnt == cnt) return;
+
+    u8 oldofs = (oldcnt >> 3) & 0x7;
+    u8 ofs = (cnt >> 3) & 0x7;
+
+    u8* vram = VRAM[bank];
+    bank -= 5;
+
+    if (oldcnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (oldcnt & 0x3)
+        {
+        case 0:
+            VRAM_LCD[0x28] = NULL;
+            break;
+
+        case 1:
+            vrammap = &VRAM_BBG[0x02];
+            break;
+
+        case 2:
+            vrammap = &VRAM_BOBJ[0x00];
+            break;
+
+        case 3:
+            // not mapped to memory
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap++ = NULL;
+            *vrammap   = NULL;
+        }
+    }
+
+    if (cnt & (1<<7))
+    {
+        u8** vrammap = NULL;
+
+        switch (cnt & 0x3)
+        {
+        case 0:
+            VRAM_LCD[0x28] = vram;
+            break;
+
+        case 1:
+            vrammap = &VRAM_BBG[0x02];
+            break;
+
+        case 2:
+            vrammap = &VRAM_BOBJ[0x00];
+            break;
+
+        case 3:
+            // not mapped to memory
+            break;
+        }
+
+        if (vrammap)
+        {
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap++ = vram;
+            *vrammap   = vram;
+        }
+    }
+}
+
+
+void StartFrame()
+{
+    StartScanline(0);
+}
+
+void StartScanline(u32 line)
+{
+    VCount = line;
+
+    if (line == VMatch[0])
+    {
+        DispStat[0] |= (1<<2);
+
+        if (DispStat[0] & (1<<5)) NDS::TriggerIRQ(0, NDS::IRQ_VCount);
+    }
+    else
+        DispStat[0] &= ~(1<<2);
+
+    if (line == VMatch[1])
+    {
+        DispStat[1] |= (1<<2);
+
+        if (DispStat[1] & (1<<5)) NDS::TriggerIRQ(1, NDS::IRQ_VCount);
+    }
+    else
+        DispStat[1] &= ~(1<<2);
+
+    if (line < 192)
+    {
+        // TODO: draw shit
+
+        NDS::ScheduleEvent(LINE_CYCLES, StartScanline, line+1);
+    }
+    else if (line == 262)
+    {
+        // frame end
+
+        DispStat[0] &= ~(1<<0);
+        DispStat[1] &= ~(1<<0);
+    }
+    else
+    {
+        if (line == 192)
+        {
+            // VBlank
+            DispStat[0] |= (1<<0);
+            DispStat[1] |= (1<<0);
+
+            if (DispStat[0] & (1<<3)) NDS::TriggerIRQ(0, NDS::IRQ_VBlank);
+            if (DispStat[1] & (1<<3)) NDS::TriggerIRQ(1, NDS::IRQ_VBlank);
+        }
+
+        NDS::ScheduleEvent(LINE_CYCLES, StartScanline, line+1);
+    }
+}
+
+
+void SetDispStat(u32 cpu, u16 val)
+{
+    val &= 0xFFB8;
+    DispStat[cpu] &= 0x0047;
+    DispStat[cpu] |= val;
+
+    VMatch[cpu] = (val >> 8) | ((val & 0x80) << 1);
+
+    if (val & 0x10) printf("!! HBLANK ENABLED\n");
+}
 
 }