> Built into my Amiga 4000 I've got a certain IDE controller for which I
> want to write an appropiate driver.
What IDE controller?
> The reason I write to this list and not the linux-m68k or linux-ppc list
> is that my problem is not that machine dependent.
IMHO you better had CCed at least the linux-m68k list. Linux/m68k already has
drivers that `emulate' DMA, which solves half of your problem. Missing
interrupts is harder, though. I don't think you want to busy wait. Check for
completion in a timer interrupt?
> Having a closer look at the interrupts hooked into the native OS I found
> out that this controller doesn't (!) set up an interrupt. Really.
> A subprocess receives the file system commands, transfers the IDE commands
> to the hard drive or CD-ROM and maybe hangs around in a busy-wait (!) loop
> until the drive is ready to transfer data. The data transfer is done by
> the same subprocess (no DMA) and presented back to the file system.
>
> That's the problem. No interrupts.
>
> The only way to do it under Linux is to implement the same scheme, meaning
> a subprocess (kernel thread?) which does the actual transfer.
>
> Any ideas apart from ditching the controller?
>
> Carsten
>
> ------------------------------------------------------------------------------
> This post is NO, repeat NO, consent to send commercial EMail to my
> address. Violations will be prosecuted, see US code title 47.
Greetings,
Geert
--
Geert Uytterhoeven Geert.Uytterhoeven@cs.kuleuven.ac.be
Wavelets, Linux/{m68k~Amiga,PPC~CHRP} http://www.cs.kuleuven.ac.be/~geert/
Department of Computer Science -- Katholieke Universiteit Leuven -- Belgium
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