Kernel: Introduce a new model for writing devicetree drivers #25192
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This will be needed in the next commit, which moves the driver init functions calling code earlier into the boot process.
Devicetree drivers are created by using the `DEVICETREE_DRIVER` macro. That macro creates a new class deriving from `DeviceTree::Driver` and inserts it into the driver init section. The driver code then has to implement the `probe` member function, which will be called if `DeviceTree::Management` finds a node with a compatible property entry that was in the array passed as the second argument to the `DEVICETREE_DRIVER` macro. The `probe` function then will check if it supports the given node and if so, registers a `DeviceTree::DeviceRecipe` at the appropriate subsystem, which will then create a device from that recipe once it is initialized. The driver can store the necessary info it got from the devicetree, such as the physical address and interrupt numbers, in the capture list of the callback lambda stored in `DeviceRecipe::create_device`. The `DeviceTree::DeviceRecipe`s are necessary, as the `probe` functions might not be able to create an instance of the actual device class, since doing so can depend on some subsystems being initialized first.
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This driver doesn't actually get any info (like the physical address) from the devicetree node for now.
This driver doesn't actually get any info (like the physical address) from the devicetree node for now.
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This PR should make writing devicetree drivers a lot simpler and keep code duplication minimal.
This PR does not depend on #25103. But we will need that PR to actually get the physical addresses from the 'reg' properties.