1. The Mach8 doesn't have separate graphics pitches a la Mach32 (68800-6 and up), fixes the rendering in some drivers for Windows.
2. Special case for the add-on Mach8 for the mode switching (resolution only).
1. Actually mostly workarounds to make it render normally without a hitch (I hope) using the Diamond Stealth VRAM 911-based 15bpp driver.
2. Updated logs.
Matches my AMD Stoney + S3 Trio64V2, and also Intel's 2023 GPU docs (which *still* tend to be more accurate than IBM's), and makes more sense than what we've (I've?) been doing.
1. Do not stall the guest when the passthrough mode is on, fixes hang ups in Windows 3.1 using the 2.3 drivers.
2. In the pitch register, make sure the passthrough goes on when needed only on the ATI Mach32, not 8, fixes mode on/off in text mode when needed.
3. Cosmetic changes and logs.
1. See above, as best as possible, but manuals would be helpful.
2. Reverted the ramdac of the 924 to the sierra one because of a bug that triggers 24bpp mode when it shouldn't.
This patch fixes the pitch that was originally 0 when specifying the 8514/A compatible side in the Mach8/32 cards, which should be 1024 for 8514/A compatible stuff.
1. As tiring as it seems, XOR properly the passthrough bits for mode changes. Fixes everything tested as of now (Mach8/32).
2. Implemented separate destination and source GE pitch and offsets. Fixes Windows 3.1 mach8/32 drivers using devicebitmap enabled (or dmp=1).
3. Properly fixed high and true color patterns so that the aforementioned patterns are drawn correctly in various stuff.
4. Implemented in the best possible way the CRT offset (currently in on conjunction with the GE offset).
5. On ScanToX with bpp set to 24 and dpconfig 0x6211, optmize the SRC/CUR X-Y coordinates at the end of the blit.
6. For mode changes, don't call the mode change recalctimings function if we aren't in the appropriate bits of the respective ports.
7. Separate 8514/A compatible and Extended foreground/background selection implemented, fixes Windows 3.x ATI Ultra drivers from 1992 without hacks.
8. Clear the busy flags when needed without stalling the entire guests (but not the emulator itself) (Mach8/32).
9. The MMIO regs should be enabled only when the VGA aperture has reached a graphics mode (0xA000). This fixes NT 3.x mach drivers in true color mode and making Win3.1 drivers working without a hitch at the same time.
10. Actually implement the hardware 4bpp cursor properly on Mach32.
11. Cosmetic cleanups.
This build is still in work.
* Added character drawing function to support for DOS/V Extension DSPXDA2 driver.
* Implement CRTC regs: start address, end address, line compare to support line compare scrolling in DOS/V Extension.
* Enable updating CRTC regs when output is disabled.
1. Aliases are aliases, period.
2. Actually make the ports using bit 15 of their range use the command FIFO.
3. Improved the special ATI command 0xc2b5 in the IBM bitblt side, fixes cursor issues in 24bpp mode using OS/2.
4. When the FIFO is empty, clear the busy and available flags.
5. Also reapply a workaround for 24bpp foreground color patterns in ATI command Scan To X command, fixes patterns in OS/2 and possibly elsewhere.
6. Accelerated HiColor mode, in the IBM passthrough mode, should always be enabled, for now, as well as the Extended ATI Mach32 8bpp mode when prompted, fixes OS/2 booting into the GUI in HiColor mode.
7. Dummy data path configuration values on direct linedraw should not trigger a pixtrans read when it's not needed, fixes possible hang ups in IBM/ATI mode when the busy flag remains enabled.
1. The DX/DY coordinates for BitBLT are now signed again, fixes 8514/A cursor issues.
2. Made the busy/data available processor statuses more like the ATI one for more stability and no stalls, fixes Windows 3.x and IBM OS/2 1.x (possibly later ones too) that use the built-in 8514/A driver.
3. Made the mode switching clearer (through a note) regarding the shadow sets, this should make every program happy, I hope.
4. In the Mach32 series only, a first load of the CRT sets also initializes the GE offsets if the corresponding bit is set, fixes Mach8/32 mode tests in their eeprom and demoai with hdiload from ATI/IBM.
1. Use proper identification to what chips use what.
2. Apply some mode switch fixes to the ATI 8514/A Ultra and make 1024x768 87Hz interlaced the default mode if htotal is 0 and on ati8514_init.
3. Add the undocumented ports to the ATI 8514/A Ultra add-on as well.
SVGA related:
If CRTC1/HDISP is odd (if bit 0 is set), then make it even accordingly, else leave it as is. Should fix some display skews.
S3 related:
Remove old code references (can still be accessed through history if one needs it).
8514/A compatible related:
Proper use of the htotal and hdisp timings.
1. Implemented the FIFO test data to pass some tests of the Mach8 POST ROM and tests (not complete yet).
2. Overhauled the mode switches again, but this time with way less hacks and more on manual instructions.
3. Use a function pointer to determine if the Mach8 type used is a VGA combo or add-on.
4. Mach32 mode tests are no longer incorrectly green (was caused by improper pixtrans parts).
5. Implemented overscan color to the Mach32 as well as the CRT offset.
6. And fixed a PCI LFB GPF issue with the Mach32 2.3 drivers on Win3.1x.
7. Implemented memory boundary for both the Mach32 SVGA and its accelerator.
8. Added undocumented ports used by the FIFO (such as ports 0x8AEE and 0xEAEE).
9. Plus resetting the device right a la s3.
10. Temporarily switched the bus type of the Mach8 to 8-bit in both MCA and ISA variants.
