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

["David A. Van Arnem" <dvanarnem@cmlab.biz>]

On 02/21/2017 03:30 PM, Jeff Westfahl wrote:
> 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.

Great!  Thanks for your time.

Regards,
David

> 
> 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
>>
>>

-- 
Regards,
David Van Arnem
Development Engineer IV
Computer Measurement Laboratory, LLC