simplify mmu_{wb,rb}(): add {rom,ram}_{wb,rb}()

1 files changed, 95 insertions, 25 deletions

diff --git a/ops.yaml b/ops.yaml
index 27950ac..ac4b0a7 100644
--- a/ops.yaml
+++ b/ops.yaml
@@ -7912,7 +7912,7 @@ templates:
     }
 
     static uint8_t
-    mmu_rb(
+    rom_rb(
       gb_t * const ctx,
       const uint16_t addr
     ) {
@@ -7929,14 +7929,11 @@ templates:
 
         // return ROM0 (16k, always mapped)
         return ctx->mmu.rom[addr];
-
-        break;
       case 0x1000:
       case 0x2000:
       case 0x3000:
         // return ROM0 (16k, always mapped)
         return ctx->mmu.rom[addr];
-        break;
       case 0x4000:
       case 0x5000:
       case 0x6000:
@@ -7944,12 +7941,22 @@ templates:
         // return ROM1 (16k, banked)
         // TODO:
         return ctx->mmu.rom[addr];
-        break;
+      default:
+        // never reached
+        return 0;
+      }
+    }
+
+    static uint8_t
+    ram_rb(
+      gb_t * const ctx,
+      const uint16_t addr
+    ) {
+      switch (addr & 0xF000) {
       case 0x8000:
       case 0x9000:
         // return vram (8k)
         return ctx->mmu.vram[addr & 0x1FFF];
-        break;
       case 0xA000:
       case 0xB000:
         if (ctx->mmu.eram) {
@@ -7959,17 +7966,43 @@ templates:
           // FIXME: what do we do with no eram?
           return 0;
         }
-
-        break;
       case 0xC000:
       case 0xD000:
         // working ram (8k)
         return ctx->mmu.ram[addr & 0x1FFF];
-        break;
       case 0xE000:
+      case 0xF000:
         // working ram (shadow)
         return ctx->mmu.ram[addr & 0x1FFF];
-        break;
+      default:
+        // never reached
+        return 0;
+      }
+    }
+
+    static uint8_t
+    mmu_rb(
+      gb_t * const ctx,
+      const uint16_t addr
+    ) {
+      switch (addr & 0xF000) {
+      case 0x0000:
+      case 0x1000:
+      case 0x2000:
+      case 0x3000:
+      case 0x4000:
+      case 0x5000:
+      case 0x6000:
+      case 0x7000:
+        return rom_rb(ctx, addr);
+      case 0x8000:
+      case 0x9000:
+      case 0xA000:
+      case 0xB000:
+      case 0xC000:
+      case 0xD000:
+      case 0xE000:
+        return ram_rb(ctx, addr);
       case 0xF000:
         switch (addr & 0x0F00) {
         case 0x0E00:
@@ -7980,8 +8013,6 @@ templates:
             // rest of page reads as zero
             return 0;
           }
-
-          break;
         case 0x0F00:
           if (addr == PORT_IE || addr < 0xFF80) {
             // io port
@@ -7990,14 +8021,10 @@ templates:
             // zero page
             return ctx->mmu.zram[addr & 0x7F];
           }
-
-          break;
         default:
-          // working ram (shadow)
-          return ctx->mmu.ram[addr & 0x1FFF];
+          // working ram (<0xFE00, 8k, shadow)
+          return ram_rb(ctx, addr);
         }
-
-        break;
       default:
         // never reached
         return 0;
@@ -8005,11 +8032,14 @@ templates:
     }
 
     static void
-    mmu_wb(
+    rom_wb(
       gb_t * const ctx,
       const uint16_t addr,
       const uint8_t val
     ) {
+      // TODO: implement banking
+      UNUSED(val);
+
       switch (addr & 0xF000) {
       case 0x0000:
         // bios memory (maybe)
@@ -8038,6 +8068,19 @@ templates:
         // ROM1 (16k, banked)
         // return ctx->mmu.rom[addr];
         break;
+      default:
+        // never reached
+        break;
+      }
+    }
+
+    static void
+    ram_wb(
+      gb_t * const ctx,
+      const uint16_t addr,
+      const uint8_t val
+    ) {
+      switch (addr & 0xF000) {
       case 0x8000:
       case 0x9000:
         // vram (8k)
@@ -8054,14 +8097,41 @@ templates:
         break;
       case 0xC000:
       case 0xD000:
-        // working ram (8k)
+      case 0xE000:
+      case 0xF000:
+        // working ram (8k, shadow)
         ctx->mmu.ram[addr & 0x1FFF] = val;
+      default:
+        // never reached
+        break;
+      }
+    }
 
+    static void
+    mmu_wb(
+      gb_t * const ctx,
+      const uint16_t addr,
+      const uint8_t val
+    ) {
+      switch (addr & 0xF000) {
+      case 0x0000:
+      case 0x1000:
+      case 0x2000:
+      case 0x3000:
+      case 0x4000:
+      case 0x5000:
+      case 0x6000:
+      case 0x7000:
+        rom_wb(ctx, addr, val);
         break;
+      case 0x8000:
+      case 0x9000:
+      case 0xA000:
+      case 0xB000:
+      case 0xC000:
+      case 0xD000:
       case 0xE000:
-        // working ram (shadow)
-        ctx->mmu.ram[addr & 0x1FFF] = val;
-
+        ram_wb(ctx, addr, val);
         break;
       case 0xF000:
         switch (addr & 0x0F00) {
@@ -8083,8 +8153,8 @@ templates:
 
           break;
         default:
-          // working ram (shadow)
-          ctx->mmu.ram[addr & 0x1FFF] = val;
+          // working ram (<0xFE00, 8k, shadow)
+          ram_wb(ctx, addr, val);
         }
       }
     }