Messages in this thread |  | | Date | Mon, 24 Feb 2014 17:28:50 +0000 | From | Will Deacon <> | Subject | Re: your mail |
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On Mon, Feb 24, 2014 at 03:12:21PM +0000, srikanth TS wrote: > Hi Will Deacon,
Hello,
> Currently SMMU driver expecting all stream ID used by respective master > should be defined in the DT. > > We want to know how to handle in the case of virtual functions dynamically > created and destroyed. > > Is PCI driver responsible for creating stream ID respective BDand > requesting SMMU to add to the mapping table[stream Id to context mapping > table]? > > Or is there any right way of doing it?
Correct, the driver currently doesn't support dynamic mappings (mainly because I didn't want to try and invent something that I couldn't test).
There are a couple of ways to solve this:
(1) Add a way for a PCI RC to dynamically allocate StreamIDs on an SMMU within a fixed range. That would probably need some code in the bus layer, so that a bus notifier can kick and call back to the relevant SMMU.
(2) Describe the RID -> SID mapping in the device-tree. We probably want to avoid an enormous table, so this would only work for simple `SID = RID + offset' or 'SID = RID & mask' cases.
How do your IDs map to each other?
Will
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