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Subject: Re: [PATCH V2 2/3] Add iommu driver for hi6220 SoC platform
To: Robin Murphy <robin.murphy@arm.com>, <yudongbin@hisilicon.com>,
        <saberlily.xia@hisilicon.com>, <suzhuangluan@hisilicon.com>,
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CC: <dan.zhao@hisilicon.com>, <peter.panshilin@hisilicon.com>,
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From: chenfeng <puck.chen@hisilicon.com>
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Date: Fri, 23 Oct 2015 17:10:31 +0800
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Hi Robin,

On 2015/10/20 23:02, Robin Murphy wrote:
> On 20/10/15 09:45, Chen Feng wrote:
>> iommu/hisilicon: Add hi6220-SoC smmu driver
> 

>> +
>> +static int hi6220_smmu_attach_dev(struct iommu_domain *domain,
>> +                  struct device *dev)
>> +{
>> +    dev->archdata.iommu = &iova_allocator;
> 
> If the hardware doesn't offer any kind of device isolation (i.e. multiple translation contexts), then you should probably have more logic here to ensure only a single domain can ever be active at once.
> 
>> +    return 0;
>> +}
>> +
I feel confused about your above comments. Could you help explain "ensure only a single domain can ever be active at once"?


> Robin.
> 
> 
> .
>