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Subject: Re: [PATCH v13 1/9] LIB: Introduce a generic PIO mapping method
To: dann frazier <dann.frazier@canonical.com>
References: <1518543933-22456-1-git-send-email-john.garry@huawei.com>
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From: John Garry <john.garry@huawei.com>
Message-ID: <b16db30e-67d3-0469-d8c7-029665702378@huawei.com>
Date: Wed, 14 Feb 2018 16:13:57 +0000
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On 13/02/2018 23:05, dann frazier wrote:
>>  	bool
>> >
>> > +config INDIRECT_PIO
>> > +	bool "Access I/O in non-MMIO mode"
>> > +	depends on ARM64
>> > +	help
>> > +	  On some platforms where no separate I/O space exists, there are I/O
>> > +	  hosts which can not be accessed in MMIO mode. Using the logical PIO
>> > +	  mechanism, the host-local I/O resource can be mapped into system
>> > +	  logic PIO space shared with MMIO hosts, such as PCI/PCIE, then the
>> > +	  system can access the I/O devices with the mapped logic PIO through
>> > +	  I/O accessors.
>> > +	  This way has a relatively little I/O performance cost. Please make
> grammar nit - s/a relatively/relatively/
>

Fine, thanks

John

>   -dann
>
>> > +	  sure your devices really need this configure item enabled.
>> > +