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Date: Fri, 2 Dec 2011 11:27:12 -0600
From: Scott Wood <scottwood@freescale.com>
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To: Paul Gortmaker <paul.gortmaker@windriver.com>
Subject: Re: [PATCH 3/3] 8250: add workaround for MPC8[356]xx UART break IRQ
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Cc: gregkh@suse.de, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org,
 linuxppc-dev@lists.ozlabs.org, Alan Cox <alan@lxorguk.ukuu.org.uk>,
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On 12/02/2011 10:34 AM, Paul Gortmaker wrote:
> On 11-12-02 06:30 AM, Alan Cox wrote:
>>>> OK, I'll simply change the above to CONFIG_PPC then.
>>>
>>> It does, the bug is in the uart IP which I don't think we ever plan on fixing, so 32 or 64-bit parts will have it for ever and ever ;)
>>
>> It should be runtime selected, there should be no ifdefs here.
> 
> The ifdef wasn't strictly required; it just made it so gcc would
> toss the errata code out of the irq handler for !PPC.  Anyway it
> will be a moot point if I can somehow hide all the mess by snooping
> serial_inp() traffic and deploying the errata fix from there....

Eww.

If it's not to be allowed in the main 8250 code (even for ppc builds
only), a custom handle_port sounds like a saner option.

-Scott