> On Nov 4, 2022, at 6:20 AM, d.meneses via groups.io 
> <d.meneses=softi9...@groups.io> wrote:
> 
> Using DebugLib instead to print a message, I was able to confirm that my 
> driver is now running properly:
> cat debug.log | grep Hello
> This works both when adding it in the OVMF build and also when inserted by 
> UEFITool.
> 
> The drivers is not being listed by the EFI Shell drivers command.
> This is expected to me as Dxe Drivers are unloaded after they return.
> Nonetheless, the same is happening when I package it as a DXE_RUNTIME_DRIVER.
> What is it that I'm missing?
> 

The UEFI Shell drivers command is managing UEFI Driver Model Drivers [1]. A 
UEFI Driver Model Driver has no depex and publishes an EFI Driver Binding 
protocol [2]. The idea is the BDS (platform) can now have the policy of what 
driver gets connected to what device. This is all managed by 
gBS->ConnectController()/gBS->DisconnectController(). 

A DXE Driver just publishes an arbitrary protocol. 

[1] https://uefi.org/specs/UEFI/2.10/11_Protocols_UEFI_Driver_Model.html
[2] 
https://github.com/tianocore/edk2/blob/master/MdePkg/Include/Protocol/DriverBinding.h


PS I seem to remember a question about launching an App….

It is possible to customize a generic UEFIs system boot policy via NVRAM 
variable. You can read up on that here [3]. 

If you want to change the platform policy in a secure way to do something you 
likely need to modify the BDS (Boot Device Selection). The design idea around 
BDS is you could make a system an ATM or a PC just by changing the policy in 
the BDS, thus the BDS is a place to centralize the platform policy. The easiest 
way to customize the edk2 BDS is via a custom PlatformBootManagerLib. You can 
look at the OVMF instance here [4]. You can use this library to add extra 
policy on top of the NVRAM variables in the UEFI Spec [3]. If you look at the 
OVMF example this is how the OVMF platform makes the UEFI Shell a default boot 
option [5].

[3] 
https://uefi.org/specs/UEFI/2.10/03_Boot_Manager.html#globally-defined-variables
[4] 
https://github.com/tianocore/edk2/tree/master/OvmfPkg/Library/PlatformBootManagerLib
[5] 
https://github.com/tianocore/edk2/blob/master/OvmfPkg/Library/PlatformBootManagerLib/BdsPlatform.c#L1717

Sorry if I’m mixing up threads. So much email, and so little time….

> Thank you for your attention,
> Diogo
> 



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