Apparently the Trantor T130B SCSI controllers has a different way of calculating the timings and removed the scsi_bus_read() calls from the Current SCSI bus status port (Read Port+4).
Fixes NT using said controller as well as CD swapping while maintaining the correct accurate CD speed.
XGA:
1. Added a proper poll so to have its timings independent of the SVGA core and changes its renderer accordingly, mainly a blank render one.
2. Workaround the Ctrl-Alt-Del reset of Windows 2.x so that it switches back to VGA text mode correctly when using the 0xA000 64K aperture (in vid_svga.c).
SVGA core:
Re-organized the way the different timers are organized so that the XGA and 8514/A pollers can coexist with the SVGA timer without conflicts.
ATI Mach32:
Reworked the true color renderer and made it a Mach32 exclusive due to its differences from the standard one. Fixes wrong rendered colors in NT using the 32bpp renderer in RGB mode.
1. Separate the SCSI bus functions from NCR 5380 into true general purpose SCSI bus functions, allowing use of future legacy scsi controllers.
2. Corrected NCR 5380 chip period for the SCSI controllers based on that chip so that CD-ROM speed is correct enough per speed tests and no more breakage (I hope, report if they are still there, please!) on desyncs.
3. A NCR 5380 software reset involves asserting an IRQ.
Generic SVGA layer:
Added function pointers of the banked mapping for use with add-on cards with their own mapping when the VGA card banked mapping is not active or viceversa (e.g.: XGA).
XGA-1/2:
1. Reimplemented Area Fill and Boundary Mode as best as possible.
2. Fixed conflicts with banked mapping with VGA clones.
3. Fixed inverted colors (again) on accelerated 16bpp mode under OS/2.
Video7 with ATI 8514/A add-on.
Added a workaround (BIOS issue? I don't know) that disables 8514/A mode and reenables VGA mode when needed. Fixes screen freezes and polling issues with various drivers for Windows and others.
S3:
1. Cleaned up the Short Stroke command processing.
2. Proceed calculating the error term only when it's equal or greater than the line length (Draw Line, Command 1 and also applies to Short Strokes, Command 0).
8514/A compatibles:
1. Reworked the polygon draw type A processing.
2. As with the S3, reworked the way error term is handled in the processing, and on Command 5 (Draw Polygon Boundary Line).
