Re: [PATCH] ArmPlatformPkg/ArmJunoPkg/Drivers/ArmJunoDxe: Fixed crash on Juno R0

[Ryan Harkin <ryan.harkin@linaro.org>]

On 18 January 2017 at 23:27, Daniil Egranov <daniil.egranov@arm.com> wrote:
> The Marvell Yukon MAC address load supported only on Juno R1 and R2.
> It disabled for Juno R0 due to PCI issues on this board.
>
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Daniil Egranov <daniil.egranov@arm.com>

Tested-by: Ryan Harkin <ryan.harkin@linaro.org>

> ---
>  ArmPlatformPkg/ArmJunoPkg/Drivers/ArmJunoDxe/ArmJunoDxe.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/ArmPlatformPkg/ArmJunoPkg/Drivers/ArmJunoDxe/ArmJunoDxe.c b/ArmPlatformPkg/ArmJunoPkg/Drivers/ArmJunoDxe/ArmJunoDxe.c
> index 47ff587..e9e6990 100644
> --- a/ArmPlatformPkg/ArmJunoPkg/Drivers/ArmJunoDxe/ArmJunoDxe.c
> +++ b/ArmPlatformPkg/ArmJunoPkg/Drivers/ArmJunoDxe/ArmJunoDxe.c
> @@ -378,6 +378,7 @@ OnEndOfDxe (
>    EFI_DEVICE_PATH_PROTOCOL* PciRootComplexDevicePath;
>    EFI_HANDLE                Handle;
>    EFI_STATUS                Status;
> +  UINT32                    JunoRevision;
>
>    //
>    // PCI Root Complex initialization
> @@ -393,8 +394,12 @@ OnEndOfDxe (
>    Status = gBS->ConnectController (Handle, NULL, PciRootComplexDevicePath, FALSE);
>    ASSERT_EFI_ERROR (Status);
>
> -  Status = ArmJunoSetNicMacAddress ();
> -  ASSERT_EFI_ERROR (Status);
> +  GetJunoRevision (JunoRevision);
> +
> +  if (JunoRevision != JUNO_REVISION_R0) {
> +    Status = ArmJunoSetNicMacAddress ();
> +    ASSERT_EFI_ERROR (Status);

This is just an FYI, but I stacked your patch on top of mainline, like this:

5f81f61  2017-01-18  ArmPlatformPkg/ArmJunoPkg/Drivers/ArmJunoDxe:
Fixed crash on Juno R0       [Daniil Egranov]
19ca06b  2017-01-19  OvmfPkg: Remove superfluous return statements.
 [Thomas Huth]

The first time I ran this, Juno R0 worked fine, but on R1 and R2, the
assert triggered:

UEFI firmware (version 5f81f61 built at 11:56:52 on Jan 19 2017)
[snip]
ASSERT_EFI_ERROR (Status = Not Found)
ASSERT [ArmJunoDxe]
/linaro/platforms/uefi/edk2/ArmPlatformPkg/ArmJunoPkg/Drivers/ArmJunoDxe/ArmJunoDxe.c(401):
!EFI_ERROR (Status)

I worked out what is happening. And it's not to do with this patch.
It's another fall-out from the re-work you did to the previous patch.
It's also ultimately due to a bug the firmware.

With the initial version of your "Set Marvell Yukon MAC address"
patch, this hang didn't happen. I suspect that was because your error
checking was weaker and certain PCIe failures didn't trigger the
assert.

To reproduce the error with this commit:
1) power on and boot R1 or R2 into Shell
  I do this by interrupting the boot by pressing ESCAPE and using the boot menu
2) At the Shell prompt, run "reset -s" to shutdown
3) At the ARM Boot Loader "Cmd>" prompt, run "reboot"
4) the board will hang while booting UEFI, assuming the board firmware
doesn't die with constant messages like this:

    ERROR: PCIe CSR read failed to respond
    ERROR: SMBus transaction not claimed

Assuming the problem is firmware, not EDK2, what should we do about it?

Prior to your "Set Marvell Yukon MAC address" patch, or with the
earlier version, the board would boot anyway, but the Yukon device
would be missing.

Now it dies.

I don't know which is worse, but I think hanging is worse than an
ethernet port dropping out. Although hanging is a bit more obvious
that there's a problem...


> +  }
>  }
>
>  STATIC
> --
> 2.7.4
>