gwsystems / composite

A component-based OS
composite.seas.gwu.edu
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HW capabilities only for components that need them #324

Open phanikishoreg opened 6 years ago

phanikishoreg commented 6 years ago

Currently llbooter copies it's HW capability to all components for 2 reasons:

  1. It doesn't know which component needs one and which doesn't. It could be a scheduling component or non-scheduling component that needs access to HW capability.
  2. HW capability is used for getting cpu cycles per microsecond, which is a system call. We need an alternative solution to get cpu cycles (perhaps using the current thread cap ?) and not the HW capability.

We'd probably have more information in the runscript to tell which components need access to HW resources, and the booter can create NEW HW caps with HW bitmap setting allowing components access to only those HW resources. The HW bitmap must be more abstract and not the actual IRQ line bitmap as it is not possible to know at boot-time by the loader as to which lines a component would access to access a specific device.