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Subject: Re: [PATCH] m68k/mac: Replace macide driver with generic platform
 driver
To:     Finn Thain <fthain@fastmail.com.au>
Cc:     John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Christoph Hellwig <hch@lst.de>,
        Joshua Thompson <funaho@jurai.org>,
        "David S. Miller" <davem@davemloft.net>,
        linux-m68k@lists.linux-m68k.org, linux-kernel@vger.kernel.org,
        linux-ide@vger.kernel.org
References: <793432cca963b632709c4d1312baa9874d73e1d8.1619341585.git.fthain@telegraphics.com.au>
 <ba908b1d-eab5-a4e5-0c0a-2c745287d121@physik.fu-berlin.de>
 <10a08764-c138-9fe5-966c-ce68349b9b6@nippy.intranet>
 <65f01f42-31d9-522a-e690-73d286405a01@gmail.com>
 <9650358f-a789-7dbd-4495-1d39ff321ded@nippy.intranet>
From:   Michael Schmitz <schmitzmic@gmail.com>
Message-ID: <ada88dd6-f8d7-11dc-9a89-5c7e437a0981@gmail.com>
Date:   Wed, 28 Apr 2021 07:54:52 +1200
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Hi Finn,

On 27/04/21 3:47 pm, Finn Thain wrote:
> On Tue, 27 Apr 2021, Michael Schmitz wrote:
>
>> On 26/04/21 7:37 pm, Finn Thain wrote:
>>> Was macide the only IDE driver in Debian/m68k kernels without a libata
>>> alternative? If so, this patch would allow you to finally drop
>>> CONFIG_IDE.
>>>
>> There's still q40ide.c (ISA IDE interface, byte-swapped, so would need
>> treatment similar to Falcon IDE). Hasn't been updated to a platform
>> device yet.
>>
> AIUI, q40 support is not included in Debian/m68k kernel builds.
I see.
> I wonder whether q40 could re-use the pata_falcon driver . I suppose

I'm pretty sure it could, but there is no reason why it would have to be 
crippled in that way. Interrupts should work perfectly fine with IDE on 
Q40.

There is another reason why using the same module binary for both might 
fail - the awkward address translation code in io_mm.h. Not certain at 
all whether we can even have Q40 and Atari in the same kernel binary...

> pata_falcon_set_mode() would be undesirable on q40 (?) It could be made

Not sure what the defaults are - pata_buddha.c and pata_gayle.c use the 
same code in their _set_mode(). I suspect we'd need it for Q40, too.

Cheers,

     Michael