Re: Followup : EfiTestManagedDevice() issue in driver GetControllerName() function

[Jeff Westfahl <jeff.westfahl@ni.com>]

Hi David,

You would install the protocol in the start function of your driver. When 
the start function is called, it passes you an EFI_HANDLE. You install 
your protocol on this handle.

Regards,
Jeff

On Tue, 21 Feb 2017, David A. Van Arnem wrote:

> Hi Jeff,
>
> On 02/21/2017 03:10 PM, Jeff Westfahl wrote:
>> Hello David,
>>
>> It sounds like you are trying to get a list of handles to your specific
>> devices, correct?
>
> Yes, exactly.
>
>>
>> One way to do this is to create a new protocol for your devices and
>> create an instance of this protocol when your driver attaches to a PCI
>> device. Then you can just retrieve all handles that match your new
>> protocol.
>>
>> Creating a new protocol for this use case could be as simple as just
>> allocating a unique GUID, using uuidgen or something similar. You don't
>> necessarily need to have data or functions associated with your protocol
>> for this purpose, although that may prove useful.
>
> This sounds like a simple method to accomplish what I need, thanks.  I
> assume I would install the custom protocol in the same place I install
> the Driver Binding and Component Name(2) implementations?
>
> Regards,
> David
>
>>
>> I wouldn't consider myself an expert of any kind on UEFI drivers, so if
>> others see problems with my suggestions or have better ideas, please
>> chime in.
>>
>> Regards,
>> Jeff
>>
>> On Tue, 21 Feb 2017, David A. Van Arnem wrote:
>>
>>> Hello again,
>>>
>>> I think the problem lies in my application, as upon further
>>> investigation, all the handles that publish the Component Name 2
>>> protocol appear to be failing the EfiTestManagedDevice() check (they all
>>> return EFI_UNSUPPORTED).  My eventual goal is, given a buffer of handles
>>> that publish EFI_PCI_IO_PROTOCOL, I would like to locate my specific
>>> device.  I was going to do a string comparison of the ControllerName,
>>> but this doesn't seem to be the right approach.  Is there a recommended
>>> way to accomplish this?
>>>
>>> Regards,
>>> David
>>>
>>> On 02/21/2017 01:07 PM, David A. Van Arnem wrote:
>>>> Hi all,
>>>>
>>>> I am developing a UEFI_DRIVER for a custom PCIe device.  I've followed
>>>> the UEFI Driver Model, and implemented the Driver Binding, Component
>>>> Name, and Component Name 2 protocols for my driver.  I'm trying to
>>>> retrieve the Controller Name from this driver in a UEFI_APPLICATION, but
>>>> I've run into an issue.
>>>>
>>>> In the driver's Start() function, I open the EFI_PCI_IO_PROTOCOL on
>>>> ControllerHandle using the following:
>>>>
>>>> Status = gBS->OpenProtocol (
>>>>             ControllerHandle,
>>>>             &gEfiPciIoProtocolGuid,
>>>>             (VOID **)&PciIoProtocol,
>>>>             This->DriverBindingHandle,
>>>>             ControllerHandle,
>>>>             EFI_OPEN_PROTOCOL_BY_DRIVER
>>>>     );
>>>>
>>>> And leave it open when Start() exits, unless some other part of the
>>>> Start() function fails, which doesn't appear to be happening based on my
>>>> debug messages.
>>>>
>>>> Following some of the examples in edk2, in my Component Name's
>>>> GetControllerName() function, I used EfiTestManagedDevice() to check
>>>> that the ControllerHandle opened EFI_PCI_IO_PROTOCOL:
>>>>
>>>> Status = EfiTestManagedDevice (
>>>>             ControllerHandle,
>>>>             g<devicename>DriverBinding.DriverBindingHandle,
>>>>             &gEfiPciIoProtocolGuid
>>>>     );
>>>>
>>>> Finally, to get the Controller Name in the application, I first get a
>>>> buffer of handles that publish the ComponentName2 protocol, then walk
>>>> through each and call GetControllerName().
>>>>
>>>> However, the EfiTestManagedDevice() check in my driver is returning
>>>> EFI_UNSUPPORTED, indicating the protocol is not supported on the handle.
>>>>  Furthermore, after using "load <drivername>.efi" from the shell,
>>>> openinfo on the handle returns:
>>>>
>>>> Handle 188 (6E16A798)
>>>> ComponentName2
>>>> ComponentName
>>>> DriverBinding
>>>>   Drv[01] Ctrl[ ] Cnt(200) HandProt  Image(<null string>)
>>>> ImageDevicePath
>>>>   Drv[187] Ctrl[ ] Cnt(01) GetProt  Image(<null string>)
>>>> LoadedImage
>>>>   Drv[01] Ctrl[ ] Cnt(09) HandProt  Image(<null string>)
>>>>
>>>> I feel like maybe I'm missing a step here.  Should I see PciIo in
>>>> openinfo?  Do I need to open a "child" instance of the ControllerHandle
>>>> in my application to get EfiTestManagedDevice() to pass?  I'm not sure
>>>> if that's the right terminology, I'm having a little difficulty
>>>> understanding the "child" concept in this context.  Any tips
>>>> appreciated.
>>>>
>>>
>>> --
>>> Regards,
>>> David Van Arnem
>>> Development Engineer IV
>>> Computer Measurement Laboratory, LLC
>>>
>>> _______________________________________________
>>> edk2-devel mailing list
>>> edk2-devel@lists.01.org
>>> https://lists.01.org/mailman/listinfo/edk2-devel
>>>
>
> -- 
> Regards,
> David Van Arnem
> Development Engineer IV
> Computer Measurement Laboratory, LLC
>
>