Minix

[rabindranath72]

Originally Posted by redblade

I will be interested in this .

When did you change development to Amiga or were you using Hatari for part of the development process?

I'll post links here as soon as I have the stuff ready.
Development happened fully under Atari MINIX running on Hatari. Now that I have Amiga MINIX up and running, I'll switch development to hardware A1200 and WinUAE (also because the xfs filesystem device for Amiga OS allows easy porting of files to/from MINIX; under TOS/MiNT it was somewhat laborious as I needed to switch emulators.)

[redblade]

Great work. Do you think it would be possible to change the disk format to a 880k size one native for the Amiga? Because it's V7 UNIX compatible it should be able to recompile UNIX V7 to it??

Great work by the way

[rabindranath72]

Originally Posted by redblade

Great work. Do you think it would be possible to change the disk format to a 880k size one native for the Amiga? Because it's V7 UNIX compatible it should be able to recompile UNIX V7 to it??

Great work by the way

Thanks!
I don't see any major issues, however the idea of using the 720k format is because MINIX uses the IBM PC format (which is also in use on the Atari ST). In fact, the Amiga floppy disk driver is an awfully complex piece of software: it reads the Amiga binary tracks and converts them to MFM and vice-versa.
I may look into it at some point in the distant future, but to be honest, I never thought about it as an issue.

What do you mean by "recompile UNIX v7?" MINIX is compatible with UV7 at the source level, but the binaries are not compatible (I have never seen the sources of the 68k ports; there's been one or two, IIRC.)

Next steps:
1) Try to make the ATA driver more efficient by using interrupts.
2) Try to use the 68030 MMU to replace the shadowing hack.

[gulliver]

@rabindranath72

Looks like you made quite some notable progress!

I am looking forward to test your WinUAE hardfile.

[kepa]

@rabindranath

Hi!
New member here, but not new to Amiga. It's been a long time since your last update. Any progress?

I'm very interested in your development project, but only the IDE side of it, not the memory management upgrades. You see, on my A500, I have a 50 MHz 68000 turbo card with (supposedly) A600 compatible IDE interface on it. I'm not sure if the A1200 and A600 interfaces are totally compatible, and I don't know if it's possible to get the turbo card's interface to work with Minix, but I'd like to give it a go. Would you be willing to share your source files?

[rabindranath72]

Hi all,
sorry for disappearing off the radar, with the Covid pandemic things have been pretty hectic. I can't believe it's been two years since I last posted! (and two years since I last worked with my A1200... )

As I promised, I am going to share my work. For now, the source code of the driver. I'll try and prepare a WinUAE image, and share a compiled kernel image for use with floppies to try immediately on a A1200.
But if you feel brave, compile the sources below

A few comments:
- A small change is necessary to the kernel/main.c file before compiling the kernel: replace the call to a590_int() with ata_int()
- There's no Makefile, however the dependencies are quite simple

As for the general characteristics:
- LBA28 addressing
- Supports up to two drives (no IDE doubler, though)
- Up to 7 partitions per drive
- MINIX partitions are limited to 32Mb
- This version fully supports interrupts (though on A1200 the system is quite inefficient as it's slaved to the CIA-A)
- Tested on A1200, both physical hardware (using a CF 128Mb drive) and WinUAE emulation. It should work on A600 too, but I haven't tested it yet. It would require some changes to work on A4000 (not really interested in supporting this at the moment)
- Uses Fast memory if available for buffering

I have started looking at the source code of MINIX 2.0.4, which a brave soul has already ported to the Atari ST/TT family, so hopefully I'll manage to do the same for the A1200.

Comments/questions are welcome!

Antonio

[Roodemol]

I have registered myself specially for this topic on EAB to stay up to date. I also interested in UAE images.