RE: [EXTERNAL] Re: unable to get virtual serial console for EFI

Hi Warner,

The ConOut is :

global NV,BS,RS ConOut = AcpiEx(VMBus,,)/VenHw(9B17E5A2-0891-42DD-B653-80B5C22809BA,02780ADA77E3AC4A8E770558EB1073F8C7E020566280CE4DAEB7520C7EF76171)

Regards,
Souradeep

From: Warner Losh <imp@bsdimp.com>
Sent: Tuesday, May 24, 2022 8:23 PM
To: Souradeep Chakrabarti <schakrabarti@microsoft.com>
Cc: arm@freebsd.org; Wei Hu <weh@microsoft.com>
Subject: [EXTERNAL] Re: unable to get virtual serial console for EFI

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What does the ComOut variable say?

Warner


On Mon, May 23, 2022 at 3:57 AM Souradeep Chakrabarti <schakrabarti@microsoft.com<mailto:schakrabarti@microsoft.com>> wrote:
Hi,
I am trying to get the virtual serial console to access via putty while booting FreeBSD 13 arm64 bootonly on Hyper-V.


Setting console="efi" is not helping to have the virtual serial console access using putty for ARM64. It is before any kernel module loaded.

I can get the loader output in vmconnect.exe but not in the putty.



Though I can see VM is getting connected to Hyper-V virtual COM1 console. But no output is coming to putty.



I have following question :

Any specific support from EFI firmware, is required for virtual serial to work in EFI loader in this phase of loading?



I can see FreeBSD EFI loader is able to read the ConInDev and ConOutDev variables.



With set console="efi" or set console="comconsole,efi"  or set console="efi" , nothing in getting redirected in putty in arm64.

But in X86 that is not the problem.



Without this debugging the bring up of FreeBSD on arm64 Hyper-V is quite difficult. Any help or pointers are really appreciated.



Regards,

Souradeep