[Qemu-devel] [PATCH] Cirrus bugfixes

[Volker Ruppert]

Hi all,

here are some fixes for the Cirrus emulation. The patch fixes problems with 
the ISA version when running Win 3.11 and some display errors in Win95/98 and 
maybe others.

 - partial implementation of the destination write mask (bit 7 unhandled)
 - fixed banked memory access of the ISA version
 - the bus type bits in sequencer reg 0x17 must be readonly
 - fixed destination write mask in debug message

diff -urN /home/volker/qemu/hw/cirrus_vga.c ./hw/cirrus_vga.c
--- /home/volker/qemu/hw/cirrus_vga.c   2005-01-26 21:35:30.000000000 +0100
+++ ./hw/cirrus_vga.c   2005-04-10 15:28:17.000000000 +0200
@@ -800,7 +800,7 @@
            s->cirrus_blt_srcpitch,
            s->cirrus_blt_dstaddr,
            s->cirrus_blt_srcaddr,
-           s->sr[0x2f]);
+           s->gr[0x2f]);
 #endif
 
     switch (s->cirrus_blt_mode & CIRRUS_BLTMODE_PIXELWIDTHMASK) {
@@ -1042,10 +1042,10 @@
     else
        offset <<= 12;
 
-    if (s->vram_size <= offset)
+    if (s->real_vram_size <= offset)
        limit = 0;
     else
-       limit = s->vram_size - offset;
+       limit = s->real_vram_size - offset;
 
     if (((s->gr[0x0b] & 0x01) == 0) && (bank_index != 0)) {
        if (limit > 0x8000) {
@@ -1213,7 +1213,7 @@
 #endif
        break;
     case 0x17:                 // Configuration Readback and Extended Control
-       s->sr[reg_index] = reg_value;
+       s->sr[reg_index] = (s->sr[reg_index] & 0x38) | (reg_value & 0xc7);
         cirrus_update_memory_access(s);
         break;
     default:
diff 
-urNX /home/volker/exclude-qemu /home/volker/qemu/hw/cirrus_vga_rop2.h 
./hw/cirrus_vga_rop2.h
--- /home/volker/qemu/hw/cirrus_vga_rop2.h      2004-07-06 17:35:16.000000000 
+0200
+++ ./hw/cirrus_vga_rop2.h      2005-04-12 17:48:31.106020808 +0200
@@ -47,6 +47,7 @@
     int x, y, pattern_y, pattern_pitch, pattern_x;
     unsigned int col;
     const uint8_t *src1;
+    int skipleft = (s->gr[0x2f] & 0x07) * (DEPTH / 8);
 
 #if DEPTH == 8
     pattern_pitch = 8;
@@ -56,11 +57,11 @@
     pattern_pitch = 32;
 #endif
     pattern_y = s->cirrus_blt_srcaddr & 7;
-    pattern_x = 0;
+    pattern_x = skipleft;
     for(y = 0; y < bltheight; y++) {
-        d = dst;
+        d = dst + skipleft;
         src1 = src + pattern_y * pattern_pitch;
-        for (x = 0; x < bltwidth; x += (DEPTH / 8)) {
+        for (x = skipleft; x < bltwidth; x += (DEPTH / 8)) {
 #if DEPTH == 8
             col = src1[pattern_x];
             pattern_x = (pattern_x + 1) & 7;
@@ -99,7 +100,8 @@
     unsigned int col;
     unsigned bitmask;
     unsigned index;
-    int srcskipleft = 0;
+    int srcskipleft = s->gr[0x2f] & 0x07;
+    int dstskipleft = srcskipleft * (DEPTH / 8);
 
     if (s->cirrus_blt_modeext & CIRRUS_BLTMODEEXT_COLOREXPINV) {
         bits_xor = 0xff;
@@ -112,8 +114,8 @@
     for(y = 0; y < bltheight; y++) {
         bitmask = 0x80 >> srcskipleft;
         bits = *src++ ^ bits_xor;
-        d = dst;
-        for (x = 0; x < bltwidth; x += (DEPTH / 8)) {
+        d = dst + dstskipleft;
+        for (x = dstskipleft; x < bltwidth; x += (DEPTH / 8)) {
             if ((bitmask & 0xff) == 0) {
                 bitmask = 0x80;
                 bits = *src++ ^ bits_xor;
@@ -142,15 +144,16 @@
     unsigned bits;
     unsigned int col;
     unsigned bitmask;
-    int srcskipleft = 0;
+    int srcskipleft = s->gr[0x2f] & 0x07;
+    int dstskipleft = srcskipleft * (DEPTH / 8);
 
     colors[0] = s->cirrus_blt_bgcol;
     colors[1] = s->cirrus_blt_fgcol;
     for(y = 0; y < bltheight; y++) {
         bitmask = 0x80 >> srcskipleft;
         bits = *src++;
-        d = dst;
-        for (x = 0; x < bltwidth; x += (DEPTH / 8)) {
+        d = dst + dstskipleft;
+        for (x = dstskipleft; x < bltwidth; x += (DEPTH / 8)) {
             if ((bitmask & 0xff) == 0) {
                 bitmask = 0x80;
                 bits = *src++;
@@ -175,6 +178,8 @@
     int x, y, bitpos, pattern_y;
     unsigned int bits, bits_xor;
     unsigned int col;
+    int srcskipleft = s->gr[0x2f] & 0x07;
+    int dstskipleft = srcskipleft * (DEPTH / 8);
 
     if (s->cirrus_blt_modeext & CIRRUS_BLTMODEEXT_COLOREXPINV) {
         bits_xor = 0xff;
@@ -187,9 +192,9 @@
 
     for(y = 0; y < bltheight; y++) {
         bits = src[pattern_y] ^ bits_xor;
-        bitpos = 7;
-        d = dst;
-        for (x = 0; x < bltwidth; x += (DEPTH / 8)) {
+        bitpos = 7 - srcskipleft;
+        d = dst + dstskipleft;
+        for (x = dstskipleft; x < bltwidth; x += (DEPTH / 8)) {
             if ((bits >> bitpos) & 1) {
                 PUTPIXEL();
             }
@@ -213,6 +218,8 @@
     int x, y, bitpos, pattern_y;
     unsigned int bits;
     unsigned int col;
+    int srcskipleft = s->gr[0x2f] & 0x07;
+    int dstskipleft = srcskipleft * (DEPTH / 8);
 
     colors[0] = s->cirrus_blt_bgcol;
     colors[1] = s->cirrus_blt_fgcol;
@@ -220,9 +227,9 @@
 
     for(y = 0; y < bltheight; y++) {
         bits = src[pattern_y];
-        bitpos = 7;
-        d = dst;
-        for (x = 0; x < bltwidth; x += (DEPTH / 8)) {
+        bitpos = 7 - srcskipleft;
+        d = dst + dstskipleft;
+        for (x = dstskipleft; x < bltwidth; x += (DEPTH / 8)) {
             col = colors[(bits >> bitpos) & 1];
             PUTPIXEL();
             d += (DEPTH / 8);