DOS ain't dead

SSE in DOS under JEMM386 ?? (DOSX)

posted by Rugxulo , Usono, 07.01.2008, 14:49

> > Would it be so horrible for JEMM386 or even HDPMI32 to automagically
> > enable SSE and FXSAVE/FXRESTORE for us?
>
> HDPMI does it. And Jemm intentionally touches only those bits in CR4 which
> it needs for its own purposes (VME, PGE).
>
> If you need it in DOS with Jemm, run a DEBUG script:
>
> a
> mov eax,cr4
> or ax,200
> mov cr4,eax
> mov ah,4c
> int 21
>
> g
> q

I don't think that's correct (and won't work in MS' 8086-only debug, you obviously need FD debug or similar, heh). At least, from what I gather, you have to turn on the MP bit and turn off the EM bit in CR0 and then enable OSFXSR in CR4. Then, it works in DOS (even without the need for FXSAVE/FXRSTOR). However, you need either a Pentium 4 or a AMD64 to use SSE2 (but SSE should work on Athlon XP or Pentium 3).

P.S. I read (and have now seen) that some late model Pentium 2s (e.g. bro's Intel Celeron "Mendocino" 366 Mhz) have the OSFXSR feature yet don't have SSE. Anyone know any good reason why??

---
Know your limits.h

Complete thread:

• SSE in DOS under JEMM386 ?? - Rugxulo, 03.01.2008, 06:54 (DOSX)
  • SSE in DOS under JEMM386 ?? - DOS386, 03.01.2008, 08:12
    • SSE in DOS under JEMM386 ?? - Rugxulo, 04.01.2008, 01:03
  • SSE in DOS under JEMM386 ?? - Japheth, 03.01.2008, 09:19
    • SSE in DOS under JEMM386 ?? - Rugxulo, 04.01.2008, 01:05
      • SSE in DOS under JEMM386 ?? - Japheth, 04.01.2008, 09:44
        • SSE in HDPMI / bug (c/c) - DOS386, 04.01.2008, 10:20
          • SSE in HDPMI / bug (c/c) - Japheth, 04.01.2008, 11:12
            • SSE in HDPMI / bug (c/c) - Rugxulo, 04.01.2008, 22:39
        • SSE in DOS under JEMM386 ?? - Rugxulo, 07.01.2008, 14:49
          • SSE in DOS under JEMM386 ?? - Japheth, 07.01.2008, 17:42
            • SSE in DOS under JEMM386 ?? - Rugxulo, 09.01.2008, 01:23
              • SSE in DOS under JEMM386 ?? - Rugxulo, 09.01.2008, 10:46
                • SSE in DOS -> Illegal Instruction Exception - DOS386, 10.01.2008, 01:22
                  • SSE in DOS -> Illegal Instruction Exception - Steve, 10.01.2008, 08:46
                  • SSE in DOS -> alignment issues - Rugxulo, 10.01.2008, 22:21
                • SSE in DOS under JEMM386 ?? - Japheth, 10.01.2008, 17:19
  • SSE in pure DOS - Rugxulo, 04.01.2008, 06:09
    • Secure Socket Extremism in DOS | You maybe have a Page Foul - DOS386, 04.01.2008, 07:52
      • SSE in DOS | Page Fault | JEMM386 / HDPMI32 - Rugxulo, 04.01.2008, 22:47
        • SSE in DOS | Page Fault <- YES, your bug | HDPMI32 - DOS386, 05.01.2008, 02:19
          • SSE2 in DOS | PAQ8o8z (Jan. 6) - Rugxulo, 06.01.2008, 05:09
            • SSE2 in DOS | PAQ8o8z (Jan. 6) - DOS386, 08.01.2008, 02:00
  • MS the "only hope"? - Japheth, 04.01.2008, 12:11
    • MS the "only hope"? - RayeR, 04.01.2008, 18:09
      • MS the "only hope"? - Japheth, 04.01.2008, 19:16
        • MS the "only hope"? - RayeR, 04.01.2008, 22:17
        • MS the "only hope"? (Vista DPMI bug: 32 MB max.) - Rugxulo, 04.01.2008, 22:31
          • MS the "only hope" ? NOT for me !!! - DOS386, 05.01.2008, 02:22
            • MS the "only hope" ? NOT for me !!! - RayeR, 05.01.2008, 18:58
              • MS the "only hope" ? NOT for me !!! Multiboot - DOS386, 08.01.2008, 01:47
                • NTVDM forever! - Japheth, 08.01.2008, 09:02
                • MS the "only hope" ? NOT for me !!! Multiboot - Steve, 08.01.2008, 13:54
                • MS the "only hope" ? NOT for me !!! Multiboot - Rugxulo, 09.01.2008, 01:19
                • MS the "only hope" ? NOT for me !!! Multiboot - RayeR, 14.01.2008, 21:34
          • A TSR worth a try in Vista - Japheth, 05.01.2008, 11:04
            • A TSR worth a try in Vista - Rugxulo, 05.01.2008, 21:08
              • A TSR worth a try in Vista - Khusraw, 07.01.2008, 11:06
                • A TSR worth a try in Vista - Rugxulo, 07.01.2008, 14:44
                • A TSR worth a try in Vista - Japheth, 07.01.2008, 17:34
                • A TSR worth a try in Vista - Rugxulo, 09.01.2008, 01:09