Some fixes to mem.c;

Correctly implemented the 256k wrap around on the ET4000AX, fixes DOS/V.

src/mem.c

@@ -12,7 +12,7 @@
  *		the DYNAMIC_TABLES=1 enables this. Will eventually go
  *		away, either way...
  *
- * Version:	@(#)mem.c	1.0.10	2018/04/29
+ * Version:	@(#)mem.c	1.0.11	2018/08/20
  *
  * Authors:	Fred N. van Kempen, <decwiz@yahoo.com>
  *		Miran Grca, <mgrca8@gmail.com>
@@ -1174,6 +1174,69 @@ mem_write_raml(uint32_t addr, uint32_t val, void *priv)
     mem_write_raml_page(addr, val, &pages[addr >> 12]);
 }
 
+
+static uint8_t
+mem_read_remapped(uint32_t addr, void *priv)
+{
+    if(addr >= (mem_size * 1024) && addr < ((mem_size + 384) * 1024))
+	addr = 0xA0000 + (addr - (mem_size * 1024));
+    addreadlookup(mem_logical_addr, addr);
+    return ram[addr];
+}
+
+
+static uint16_t
+mem_read_remappedw(uint32_t addr, void *priv)
+{
+    if(addr >= mem_size * 1024 && addr < ((mem_size + 384) * 1024))
+	addr = 0xA0000 + (addr - (mem_size * 1024));
+    addreadlookup(mem_logical_addr, addr);
+    return *(uint16_t *)&ram[addr];
+}
+
+
+static uint32_t
+mem_read_remappedl(uint32_t addr, void *priv)
+{
+    if(addr >= mem_size * 1024 && addr < ((mem_size + 384) * 1024))
+	addr = 0xA0000 + (addr - (mem_size * 1024));
+    addreadlookup(mem_logical_addr, addr);
+    return *(uint32_t *)&ram[addr];
+}
+
+
+static void
+mem_write_remapped(uint32_t addr, uint8_t val, void *priv)
+{
+    uint32_t oldaddr = addr;
+    if(addr >= mem_size * 1024 && addr < ((mem_size + 384) * 1024))
+	addr = 0xA0000 + (addr - (mem_size * 1024));
+    addwritelookup(mem_logical_addr, addr);
+    mem_write_ramb_page(addr, val, &pages[oldaddr >> 12]);
+}
+
+
+static void
+mem_write_remappedw(uint32_t addr, uint16_t val, void *priv)
+{
+    uint32_t oldaddr = addr;
+    if(addr >= mem_size * 1024 && addr < ((mem_size + 384) * 1024))
+	addr = 0xA0000 + (addr - (mem_size * 1024));
+    addwritelookup(mem_logical_addr, addr);
+    mem_write_ramw_page(addr, val, &pages[oldaddr >> 12]);
+}
+
+
+static void
+mem_write_remappedl(uint32_t addr, uint32_t val, void *priv)
+{
+    uint32_t oldaddr = addr;
+    if(addr >= mem_size * 1024 && addr < ((mem_size + 384) * 1024))
+	addr = 0xA0000 + (addr - (mem_size * 1024));
+    addwritelookup(mem_logical_addr, addr);
+    mem_write_raml_page(addr, val, &pages[oldaddr >> 12]);
+}
+
 
 uint8_t
 mem_read_bios(uint32_t addr, void *priv)
@@ -1605,7 +1668,7 @@ mem_reset(void)
      */
     if (mem_size < 16384)
 	m = 1024UL * 16384;
-      else
+    else
 	m = 1024UL * mem_size;
     if (ram != NULL) {
 	free(ram);
@@ -1675,13 +1738,22 @@ mem_log("MEM: reset: new pages=%08lx, pages_sz=%i\n", pages, pages_sz);
 #endif
 
     memset(pages, 0x00, pages_sz*sizeof(page_t));
-
+
 
     for (c = 0; c < pages_sz; c++) {
 	pages[c].mem = &ram[c << 12];
 	pages[c].write_b = mem_write_ramb_page;
 	pages[c].write_w = mem_write_ramw_page;
 	pages[c].write_l = mem_write_raml_page;
+    }
+
+    if (pages_sz > 256) {
+	for (c = ((mem_size * 1024) >> 12); c < (((mem_size + 256) * 1024) >> 12); c++) {
+		pages[c].mem = &ram[0xA0000 + ((c - ((mem_size * 1024) >> 12)) << 12)];
+		pages[c].write_b = mem_write_ramb_page;
+		pages[c].write_w = mem_write_ramw_page;
+		pages[c].write_l = mem_write_raml_page;
+	}
     }
 
     /* Initialize the tables. */
@@ -1745,10 +1817,10 @@ mem_log("MEM: reset: new pages=%08lx, pages_sz=%i\n", pages, pages_sz);
     if (romset == ROM_IBMPS1_2011)
 	mem_mapping_add(&romext_mapping, 0xc8000, 0x08000,
 			mem_read_romext,mem_read_romextw,mem_read_romextl,
-			NULL,NULL, NULL, romext, 0, NULL);
+			NULL,NULL, NULL, romext, 0, NULL);
-
+
-    mem_mapping_add(&ram_remapped_mapping, mem_size * 1024, 384 * 1024,
+    mem_mapping_add(&ram_remapped_mapping, mem_size * 1024, 256 * 1024,
-		    mem_read_ram,mem_read_ramw,mem_read_raml,
+		    mem_read_remapped, mem_read_remappedw, mem_read_remappedl,
 		    mem_write_remapped, mem_write_remappedw, mem_write_remappedl,
 		    ram + 0xA0000, MEM_MAPPING_INTERNAL, NULL);
     mem_mapping_disable(&ram_remapped_mapping);

src/video/vid_et4000.c

@@ -8,7 +8,7 @@
  *
  *		Emulation of the Tseng Labs ET4000.
  *
- * Version:	@(#)vid_et4000.c	1.0.9	2018/08/16
+ * Version:	@(#)vid_et4000.c	1.0.10	2018/08/22
  *
  * Authors:	Sarah Walker, <http://pcem-emulator.co.uk/>
  *		Miran Grca, <mgrca8@gmail.com>
@@ -57,6 +57,7 @@ typedef struct et4000_t
         int get_korean_font_enabled;
         int get_korean_font_index;
         uint16_t get_korean_font_base;
+	uint32_t vram_mask;
 } et4000_t;
 
 static uint8_t crtc_mask[0x40] =
@@ -103,6 +104,10 @@ void et4000_out(uint16_t addr, uint8_t val, void *p)
                 old = svga->crtc[svga->crtcreg];
                 val &= crtc_mask[svga->crtcreg];
                 svga->crtc[svga->crtcreg] = val;
+
+		if (svga->crtcreg == 0x36)
+			svga->vram_display_mask = (val & 0x20) ? et4000->vram_mask : 0x3ffff;
+
                 if (old != val)
                 {
                         if (svga->crtcreg < 0xE || svga->crtcreg > 0x10)
@@ -113,7 +118,7 @@ void et4000_out(uint16_t addr, uint8_t val, void *p)
                 }
 				
 		/*Note - Silly hack to determine video memory size automatically by ET4000 BIOS.*/
-                if(svga->crtcreg == 0x37 && !et4000->is_mca)
+                if (svga->crtcreg == 0x37 && !et4000->is_mca)
                 {
                         switch(val & 0x0B)
                         {
@@ -133,19 +138,19 @@ void et4000_out(uint16_t addr, uint8_t val, void *p)
                                 case 0x03:
                                 case 0x08:
                                 case 0x09:
-                                if(svga->vram_max == 256 * 1024)
+                                if (svga->vram_max == 256 * 1024)
                                 	mem_mapping_enable(&svga->mapping);
                                 else
                                 	mem_mapping_disable(&svga->mapping);
                                 break;
                                 case 0x0A:
-                                if(svga->vram_max == 512 * 1024)
+                                if (svga->vram_max == 512 * 1024)
                                 	mem_mapping_enable(&svga->mapping);
                                 else
                                 	mem_mapping_disable(&svga->mapping);
                                 break;
                                 case 0x0B:
-                                if(svga->vram_max == 1024 * 1024)
+                                if (svga->vram_max == 1024 * 1024)
                                 	mem_mapping_enable(&svga->mapping);
                                 else
                                 	mem_mapping_disable(&svga->mapping);
@@ -377,6 +382,7 @@ void *et4000_isa_init(const device_t *info)
                    et4000_in, et4000_out,
                    NULL,
                    NULL);
+	et4000->vram_mask = (device_get_config_int("memory") << 10) - 1;
         
         return et4000;
 }
@@ -402,6 +408,7 @@ void *et4000k_isa_init(const device_t *info)
                    et4000k_in, et4000k_out,
                    NULL,
                    NULL);
+	et4000->vram_mask = (device_get_config_int("memory") << 10) - 1;
 
         et4000->svga.ksc5601_sbyte_mask = 0x80;
 
@@ -447,6 +454,7 @@ void *et4000_mca_init(const device_t *info)
 			   et4000_in, et4000_out,
 			   NULL,
 			   NULL);	
+	et4000->vram_mask = (1 << 20) - 1;
 
 	io_sethandler(0x03c0, 0x0020, et4000_in, NULL, NULL, et4000_out, NULL, NULL, et4000);