Merge pull request #61 from LIV2/wip-crap

Add DF1-3 bootselect, Add option to move slow ram to chip ram

default.cfg

@@ -79,3 +79,10 @@ keyboard k nograb noautoconnect
 # Syntax is mouse [device] [toggle key] [autoconnect|noautoconnect]
 # (see "keyboard" above for autoconnect description)
 mouse /dev/input/mice m noautoconnect
+
+# Uncommenting below moves slow ram to the chip ram giving 1MB of chip ram
+# NOTE: Requires a 1MB ECS Agnus (8372) and a trapdoor memory expansion!
+#setvar move-slow-to-chip
+
+# Swap DF0 with DF1/2/3 - Useful for Kickstart 1.x / Trackloader games that will only boot from DF0
+#setvar swap-df0-df 1

emulator.c

@@ -42,6 +42,9 @@
 int kb_hook_enabled = 0;
 int mouse_hook_enabled = 0;
 int cpu_emulation_running = 1;
+int swap_df0_with_dfx = 0;
+int spoof_df0_id = 0;
+int move_slow_to_chip = 0;
 
 uint8_t mouse_dx = 0, mouse_dy = 0;
 uint8_t mouse_buttons = 0;
@@ -867,6 +870,13 @@ static inline int32_t platform_read_check(uint8_t type, uint32_t addr, uint32_t
             *res = (rres ^ 0x40);
             return 1;
           }
+          if (swap_df0_with_dfx && spoof_df0_id) {
+            // DF0 doesn't emit a drive type ID on RDY pin
+            // If swapping DF0 with DF1-3 we need to provide this ID so that DF0 continues to function.
+            rres = (uint32_t)ps_read(type, addr);
+            *res = (rres & 0xDF); // Spoof drive id for swapped DF0 by setting RDY low
+            return 1;
+          }
           return 0;
           break;
         case CIAAICR:
@@ -940,10 +950,36 @@ static inline int32_t platform_read_check(uint8_t type, uint32_t addr, uint32_t
           }
           return 0;
           break;
+        case CIABPRB:
+          if (swap_df0_with_dfx) {
+            uint32_t result = (uint32_t)ps_read(type, addr);
+            // SEL0 = 0x80, SEL1 = 0x10, SEL2 = 0x20, SEL3 = 0x40
+            if (((result >> SEL0_BITNUM) & 1) != ((result >> (SEL0_BITNUM + swap_df0_with_dfx)) & 1)) { // If the value for SEL0/SELx differ
+              result ^= ((1 << SEL0_BITNUM) | (1 << (SEL0_BITNUM + swap_df0_with_dfx)));                // Invert both bits to swap them around
+            }
+            *res = result;
+            return 1;
+          }
+          return 0;
+          break;
         default:
           break;
       }
 
+      if (move_slow_to_chip && addr >= 0x080000 && addr <= 0x0FFFFF) {
+        // A500 JP2 connects Agnus' A19 input to A23 instead of A19 by default, and decodes trapdoor memory at 0xC00000 instead of 0x080000.
+        // We can move the trapdoor to chipram simply by rewriting the address.
+        addr += 0xB80000;
+        *res = ps_read(type, addr);
+        return 1;
+      }
+
+      if (move_slow_to_chip && addr >= 0xC00000 && addr <= 0xC7FFFF) {
+        // Block accesses through to trapdoor at slow ram address, otherwise it will be detected at 0x080000 and 0xC00000.
+        *res = 0;
+        return 1;
+      }
+
       if (addr >= cfg->custom_low && addr < cfg->custom_high) {
         if (addr >= PISCSI_OFFSET && addr < PISCSI_UPPER) {
           *res = handle_piscsi_read(addr, type);
@@ -962,6 +998,7 @@ static inline int32_t platform_read_check(uint8_t type, uint32_t addr, uint32_t
           return 1;
         }
       }
+
       break;
     default:
       break;
@@ -1088,10 +1125,40 @@ static inline int32_t platform_write_check(uint8_t type, uint32_t addr, uint32_t
           return 0;
           break;
         }
+        case CIABPRB:
+          if (swap_df0_with_dfx) {
+            if ((val & ((1 << (SEL0_BITNUM + swap_df0_with_dfx)) | 0x80)) == 0x80) {
+              // If drive selected but motor off, Amiga is reading drive ID.
+              spoof_df0_id = 1;
+            } else {
+              spoof_df0_id = 0;
+            }
+
+            if (((val >> SEL0_BITNUM) & 1) != ((val >> (SEL0_BITNUM + swap_df0_with_dfx)) & 1)) { // If the value for SEL0/SELx differ
+              val ^= ((1 << SEL0_BITNUM) | (1 << (SEL0_BITNUM + swap_df0_with_dfx)));             // Invert both bits to swap them around
+            }
+            ps_write(type,addr,val);
+            return 1;
+          }
+          return 0;
+          break;
         default:
           break;
       }
 
+      if (move_slow_to_chip && addr >= 0x080000 && addr <= 0x0FFFFF) {
+        // A500 JP2 connects Agnus' A19 input to A23 instead of A19 by default, and decodes trapdoor memory at 0xC00000 instead of 0x080000.
+        // We can move the trapdoor to chipram simply by rewriting the address.
+        addr += 0xB80000;
+        ps_write(type,addr,val);
+        return 1;
+      }
+
+      if (move_slow_to_chip && addr >= 0xC00000 && addr <= 0xC7FFFF) {
+        // Block accesses through to trapdoor at slow ram address, otherwise it will be detected at 0x080000 and 0xC00000.
+        return 1;
+      }
+
       if (addr >= cfg->custom_low && addr < cfg->custom_high) {
         if (addr >= PISCSI_OFFSET && addr < PISCSI_UPPER) {
           handle_piscsi_write(addr, val, type);
@@ -1109,6 +1176,7 @@ static inline int32_t platform_write_check(uint8_t type, uint32_t addr, uint32_t
           return 1;
         }
       }
+
       break;
     default:
       break;

platforms/amiga/amiga-platform.c

@@ -7,6 +7,7 @@
 #include "amiga-autoconf.h"
 #include "amiga-registers.h"
 #include "amiga-interrupts.h"
+#include "gpio/ps_protocol.h"
 #include "hunk-reloc.h"
 #include "net/pi-net-enums.h"
 #include "net/pi-net.h"
@@ -57,6 +58,10 @@ extern unsigned int a314_base;
 extern int kb_hook_enabled;
 extern int mouse_hook_enabled;
 
+extern int swap_df0_with_dfx;
+extern int spoof_df0_id;
+extern int move_slow_to_chip;
+
 #define min(a, b) (a < b) ? a : b
 #define max(a, b) (a > b) ? a : b
 
@@ -523,6 +528,18 @@ void setvar_amiga(struct emulator_config *cfg, char *var, char *val) {
             }
         }
     }
+
+    if CHKVAR("swap-df0-df")  {
+        if (val && strlen(val) != 0 && get_int(val) >= 1 && get_int(val) <= 3) {
+           swap_df0_with_dfx = get_int(val);
+           printf("[AMIGA] DF0 and DF%d swapped.\n",swap_df0_with_dfx);
+        }
+    }
+
+    if CHKVAR("move-slow-to-chip") {
+        move_slow_to_chip = 1;
+        printf("[AMIGA] Slow ram moved to Chip.\n");
+    }
 }
 
 void handle_reset_amiga(struct emulator_config *cfg) {
@@ -531,14 +548,23 @@ void handle_reset_amiga(struct emulator_config *cfg) {
     ac_z2_current_pic = 0;
     ac_z3_current_pic = 0;
 
+    spoof_df0_id = 0;
+
     DEBUG("[AMIGA] Reset handler.\n");
     DEBUG("[AMIGA] AC done - Z2: %d Z3: %d.\n", ac_z2_done, ac_z3_done);
 
     if (piscsi_enabled)
         piscsi_refresh_drives();
 
-    amiga_clear_emulating_irq();
+    if (move_slow_to_chip) {
+      int agnus_rev = ((ps_read_16(0xDFF004) >> 8) & 0x6F);
+      if (agnus_rev != 0x20) {
+        move_slow_to_chip = 0;
+        printf("[AMIGA] Requested move slow ram to chip but 8372 Agnus not found - Disabling.\n");
+      }
+    }
 
+    amiga_clear_emulating_irq();
     adjust_ranges_amiga(cfg);
 }
 
@@ -581,6 +607,10 @@ void shutdown_platform_amiga(struct emulator_config *cfg) {
     kick13_mode = 0;
     cdtv_mode = 0;
 
+    swap_df0_with_dfx = 0;
+    spoof_df0_id = 0;
+    move_slow_to_chip = 0;
+
     autoconfig_reset_all();
     printf("[AMIGA] Platform shutdown completed.\n");
 }

platforms/amiga/amiga-registers.h

@@ -36,12 +36,18 @@ void adjust_gayle_1200();
 #define CIAAICR 0xBFED01
 #define CIAACRA 0xBFEE01
 #define CIAACRB 0xBFEF01
+
+#define CIABPRA 0xBFD000
+#define CIABPRB 0xBFD100
+
 #define POTGOR  0xDFF016
 #define SERDAT  0xDFF030
 
 #define DMACON  0xDFF096
 #define DMACONR 0xDFF002
 
+#define SEL0_BITNUM 3
+
 /* RAMSEY ADDRESSES */
 #define RAMSEY_REG 0xDE0003 /* just a nibble, it should return 0x08 for defaults with 16MB */
 #define RAMSEY_ID 0xDE0043  /* Either 0x0D or 0x0F (most recent version) */