From mboxrd@z Thu Jan  1 00:00:00 1970
From: santosh <santosh.shukla@caviumnetworks.com>
Subject: Re: [PATCH v4 02/15] mem: introduce IOVA type
Date: Mon, 6 Nov 2017 14:21:20 +0530
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 <20171106014141.13266-3-thomas@monjalon.net>
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Cc: olivier.matz@6wind.com, sergio.gonzalez.monroy@intel.com,
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On Monday 06 November 2017 02:07 PM, Thomas Monjalon wrote:
> 06/11/2017 06:38, santosh:
>> On Monday 06 November 2017 07:11 AM, Thomas Monjalon wrote:
>>> The IO virtual addresses may be used instead of physical addresses.
>>> As IOVA is more generic, it should be used in most places instead
>>> of physical address wording.
>>>
>>> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
>>> ---
>>> +/**
>>> + * IO virtual address type.
>>> + * When the physical addressing mode is in use,
>>> + * the translation from a virtual address to a physical address
>>> + * is a direct mapping, i.e. the same value.
>>> + */
>> I guess - that description applicable for iova=va mode
>> and for iova=pa mode - Need to do explicit virt2phy translation.
>> I believe you mis-wrote - s/physical addressing mode/virtual addressing mode.
> Not sure to understand your comment.
> Let me reword the description to be less ambiguous:
>
> * When the physical addressing mode (IOVA as PA) is in use,
> * the translation from an IO virtual address (IOVA) to a physical address
> * is a direct mapping, i.e. the same value.
> * Otherwise, in virtual mode (IOVA as VA), an IOMMU may do the translation.
>
> Is this description correct?
>
Yes.