From 663e15fd497b1a58234c671568b91f5f5b1491d1 Mon Sep 17 00:00:00 2001
From: Darius Goad <alegend45@gmail.com>
Date: Fri, 22 Jul 2016 19:08:36 -0500
Subject: [PATCH] Fix 8 MB SVGA VRAM limitations

---
 src/vid_svga.c | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/src/vid_svga.c b/src/vid_svga.c
index 76be8611b..1b7c516b1 100644
--- a/src/vid_svga.c
+++ b/src/vid_svga.c
@@ -772,7 +772,7 @@ int svga_init(svga_t *svga, void *p, int memsize,
         svga->vram = malloc(memsize);
         svga->vram_limit = memsize;
         svga->vrammask = memsize - 1;
-        svga->changedvram = malloc(/*(memsize >> 12) << 1*/0x800000 >> 12);
+        svga->changedvram = malloc(/*(memsize >> 12) << 1*/memsize >> 12);
         svga->recalctimings_ex = recalctimings_ex;
         svga->video_in  = video_in;
         svga->video_out = video_out;
@@ -848,7 +848,7 @@ void svga_write(uint32_t addr, uint8_t val, void *p)
         {
                 addr<<=2;
         }
-        addr &= 0x7fffff;
+        addr %= svga->vram_limit;
 
         if (addr >= svga->vram_limit)
                 return;
@@ -1021,7 +1021,7 @@ uint8_t svga_read(uint32_t addr, void *p)
 //        pclog("%i\n", svga->readmode);
         if (svga->chain4 || svga->fb_only) 
         { 
-                addr &= 0x7fffff;
+                addr %= svga->vram_limit;
                 if (addr >= svga->vram_limit)
                    return 0xff;
                 return svga->vram[addr];
@@ -1035,7 +1035,7 @@ uint8_t svga_read(uint32_t addr, void *p)
         else
                 addr<<=2;
         
-        addr &= 0x7fffff;
+        addr %= svga->vram_limit;
         
         if (addr >= svga->vram_limit)
            return 0xff;
@@ -1108,7 +1108,7 @@ void svga_write_linear(uint32_t addr, uint8_t val, void *p)
         {
                 addr<<=2;
         }
-        addr &= 0x7fffff;
+        addr %= svga->vram_limit;
         if (addr >= svga->vram_limit)
                 return;
         if (svga_output) pclog("%08X\n", addr);
@@ -1271,7 +1271,7 @@ uint8_t svga_read_linear(uint32_t addr, void *p)
         
         if (svga->chain4 || svga->fb_only) 
         { 
-                addr &= 0x7fffff;
+                addr %= svga->vram_limit;
                 if (addr >= svga->vram_limit)
                    return 0xff;
                 return svga->vram[addr & 0x7fffff]; 
@@ -1285,7 +1285,7 @@ uint8_t svga_read_linear(uint32_t addr, void *p)
         else
                 addr<<=2;
 
-        addr &= 0x7fffff;
+        addr %= svga->vram_limit;
         
         if (addr >= svga->vram_limit)
            return 0xff;
@@ -1400,7 +1400,7 @@ void svga_writew(uint32_t addr, uint16_t val, void *p)
 
         if (svga_output) pclog("svga_writew: %05X ", addr);
         addr = (addr & svga->banked_mask) + svga->write_bank;
-        addr &= 0x7FFFFF;        
+        addr %= svga->vram_limit;        
 	if ((!svga->extvram) && (addr >= 0x10000))  return;
         if (addr >= svga->vram_limit)
                 return;
@@ -1431,7 +1431,7 @@ void svga_writel(uint32_t addr, uint32_t val, void *p)
 
         if (svga_output) pclog("svga_writel: %05X ", addr);
         addr = (addr & svga->banked_mask) + svga->write_bank;
-        addr &= 0x7FFFFF;
+        addr %= svga->vram_limit;
 	if ((!svga->extvram) && (addr >= 0x10000))  return;
         if (addr >= svga->vram_limit)
                 return;
@@ -1457,7 +1457,7 @@ uint16_t svga_readw(uint32_t addr, void *p)
 
 //        pclog("Readw %05X ", addr);
         addr = (addr & svga->banked_mask) + svga->read_bank;
-        addr &= 0x7FFFFF;
+        addr %= svga->vram_limit;
 	if ((!svga->extvram) && (addr >= 0x10000))  return 0xffff;
 //        pclog("%08X %04X\n", addr, *(uint16_t *)&vram[addr]);
         if (addr >= svga->vram_limit) return 0xffff;
@@ -1481,7 +1481,7 @@ uint32_t svga_readl(uint32_t addr, void *p)
 
 //        pclog("Readl %05X ", addr);
         addr = (addr & svga->banked_mask) + svga->read_bank;
-        addr &= 0x7FFFFF;
+        addr %= svga->vram_limit;
 	if ((!svga->extvram) && (addr >= 0x10000))  return 0xffffffff;
 //        pclog("%08X %08X\n", addr, *(uint32_t *)&vram[addr]);
         if (addr >= svga->vram_limit) return 0xffffffff;
@@ -1508,7 +1508,7 @@ void svga_writew_linear(uint32_t addr, uint16_t val, void *p)
         cycles_lost += video_timing_w;
 
 	if (svga_output) pclog("Write LFBw %08X %04X\n", addr, val);
-        addr &= 0x7FFFFF;
+        addr %= svga->vram_limit;
 	if ((!svga->extvram) && (addr >= 0x10000))  return;
         if (addr >= svga->vram_limit)
                 return;
@@ -1537,7 +1537,7 @@ void svga_writel_linear(uint32_t addr, uint32_t val, void *p)
         cycles_lost += video_timing_l;
 
 	if (svga_output) pclog("Write LFBl %08X %08X\n", addr, val);
-        addr &= 0x7fffff;
+        addr %= svga->vram_limit;
 	if ((!svga->extvram) && (addr >= 0x10000))  return;
         if (addr >= svga->vram_limit)
                 return;
@@ -1559,7 +1559,7 @@ uint16_t svga_readw_linear(uint32_t addr, void *p)
         cycles -= video_timing_w;
         cycles_lost += video_timing_w;
 
-        addr &= 0x7FFFFF;
+        addr %= svga->vram_limit;
 	if ((!svga->extvram) && (addr >= 0x10000))  return 0xffff;
         if (addr >= svga->vram_limit) return 0xffff;
         
@@ -1580,7 +1580,7 @@ uint32_t svga_readl_linear(uint32_t addr, void *p)
         cycles -= video_timing_l;
         cycles_lost += video_timing_l;
 
-        addr &= 0x7FFFFF;
+        addr %= svga->vram_limit;
 	if ((!svga->extvram) && (addr >= 0x10000))  return 0xffffffff;
         if (addr >= svga->vram_limit) return 0xffffffff;