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Minute takers according to this page
August 1024
Apologies:
- Adam noted he has a conflicting meeting this week
August 17
Apologies:
- Dmitry
Participants:
- Peter, Adam, Oleksandr, Gunnar
Graphics discussion not fully successful today due to missing key participants, but we collected the thoughts of those who were here.
Graphics
Let's recap our thoughts and conclusions from last week's discussion
Adam: I have always thought you need hardware support to do this properly. But of course if you are already in another situation you might have to do something different.
But [the hardware-assisted solutions] involve NDAs and binary blobs (that are more difficult to analyze generally).
Peter: We discussed some similarities and a working model last week, the idea of the command queues that seems to be similar in future solutions. There are some special support for video and others. I would like to achieve this model that can progress this without being too specific on one solution. It may also avoid NDA issues. Find these common abstractions to work on. Multiple hardware should be able to be mapped into this.
Peter: We need to consider about composing images also - the display output (2D). When this is combined with other video feeds, there are safety concerns that need solutions.
Gunnar: There are some patterns for handling safety (e.g. fallback to simpler HMI if the advanced one is fails (recognizing failure in various ways)), and these patterns may drive our standardization approach.
Peter: These patterns are useful. Also considering that there are different needs - not all platforms require ASIL-B, for example.
Oleksandr: I'm not as focused on the graphics subsystem, so it's hard to say that much and what we are doing concretely is covered by NDAs. We have experience with hardware that has hardware-assistend virtualization support and we are implementing such things in Xen.
Some hardware has implemented more than one GPU and can use simple pass-through of each of these to for example 2 VMs.
Gunnar: Discussion last week with Daniel and others led to the conclusion we should start this "general model" discussion with the implementers of future graphics hardware. I feel like we need to produce a description that we can bring with us to start that conversation.
Adam: I would like to give it a try. (This week)
Gunnar: Great, and then Peter may want to add to this.
Power Management
Oleksandr: I have made some proposed edits. SCPI should be deprecated because it is now covered in SCMI and we should require the 2.0 version of SCMI.
IOMMU
Oleksandr shares some experience from Xen implementation.
Further discussion how to bring the chapter to a close, in particular the 2-stage IOMMU question that is still not brought to full conclusion.
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August 10 – Graphics/GPU focus
Participants
- Daniel Stone, Ozgur Bulkan, Adam, Dmitry, Peter, Gunnar, Oleksandr, ... ? (I missed recording the full list)
Gunnar introduced the AVPS goals a bit and mentioned that in some hardware areas (and almost surely for GPU), the AVPS specification can/should not reach the point where it requires only one way of doing things. It can still be useful to dig deeper into a few things, and then describe a few different choices through optional or conditional requirements. It is still much more useful to have that analysis done when a production project starts than to have a blank page.
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