[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-arm] [Qemu-devel] [PATCH 14/27] iommu: Add IOMMU index concept
From: |
Auger Eric |
Subject: |
Re: [Qemu-arm] [Qemu-devel] [PATCH 14/27] iommu: Add IOMMU index concept to IOMMU API |
Date: |
Tue, 22 May 2018 16:22:48 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 |
On 05/22/2018 04:19 PM, Peter Maydell wrote:
> On 22 May 2018 at 15:11, Auger Eric <address@hidden> wrote:
>> Hi Peter,
>>
>> On 05/22/2018 03:22 PM, Peter Maydell wrote:
>>> How many substream IDs do we expect to see in practice?
>>
>> Spec says max 20 bits, matching the max size of the PASID
>
> Right, but do we actually expect to see transactions from
> devices that use the whole 2^20 possible values, or will
> they in practice mostly use 1..5, or somethnig else?
An example given in the spec mentions 8.
"An example would be a compute accelerator with 8 contexts that might
each map to a different user process, but where the single device has
common configuration meaning it must be assigned to a VM whole."
Thanks
Eric
>
> thanks
> -- PMM
>
- [Qemu-arm] [PATCH 14/27] iommu: Add IOMMU index concept to IOMMU API, (continued)
Re: [Qemu-arm] [Qemu-devel] [PATCH 14/27] iommu: Add IOMMU index concept to IOMMU API, Auger Eric, 2018/05/22
Re: [Qemu-arm] [PATCH 14/27] iommu: Add IOMMU index concept to IOMMU API, Richard Henderson, 2018/05/22
[Qemu-arm] [PATCH 19/27] hw/misc/tz-mpc.c: Implement registers, Peter Maydell, 2018/05/21
[Qemu-arm] [PATCH 05/27] Make address_space_access_valid() take a MemTxAttrs argument, Peter Maydell, 2018/05/21
[Qemu-arm] [PATCH 02/27] Make tb_invalidate_phys_addr() take a MemTxAttrs argument, Peter Maydell, 2018/05/21