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Subject: Re: [PATCH] m68k/mac: Replace macide driver with generic platform
 driver
To:     Finn Thain <fthain@telegraphics.com.au>,
        Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Michael Schmitz <schmitzmic@gmail.com>,
        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>
From:   John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Message-ID: <ba908b1d-eab5-a4e5-0c0a-2c745287d121@physik.fu-berlin.de>
Date:   Sun, 25 Apr 2021 12:25:50 +0200
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On 4/25/21 11:06 AM, Finn Thain wrote:
> This was tested on my Quadra 630. I haven't tested it on my PowerBook 150
> because I don't have a RAM adapter board for it.
> 
> Apparently, the hardware I tested doesn't need macide_clear_irq() or
> macide_test_irq() -- if it did, the generic driver would not have worked.
> It's possible that those routines are needed for the PowerBook 150 but
> we can cross that bridge if and when we come to it.
> 
> BTW, macide_clear_irq() appears to suffer from a race condition. The write
> to the interrupt flags register could easily have unintended side effects
> as it may alter other flag bits. Fortunately, all of the other bits are
> unused by Linux. Moreover, when tested on my Quadra 630, that assignment
> (*ide_ifr &= ~0x20) was observed to have no effect on bit 5.

Shouldn't we switch to a libata driver instead with legacy IDE been slated
for removal from the Linux kernel?

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz@debian.org
`. `'   Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
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