help-grub
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: usb keyboard not functional in non-uefi mode


From: Jan Gregor
Subject: Re: usb keyboard not functional in non-uefi mode
Date: Thu, 11 Feb 2016 14:11:06 +0000

On Thu, Feb 11, 2016 at 12:42 PM Andrei Borzenkov <address@hidden> wrote:
On Thu, Feb 11, 2016 at 12:49 PM, Jan Gregor <address@hidden> wrote:
> Yes, it didn't worked in slax livecd until linux kernel was started. I also
> experienced same in debian installer until I disabled csm in bios that turns
> on uefi mode.
>
> I'm aware of legacy usb support in bios and it is enabled.
>

And what about other settings there? Did you try all combinations?

Yes, I hope so. There were three options for usb like ehci support and in another part of bios setup CSM options.
 

> The problem can be that microsoft natural keyboard is visible as two usb hid
> devices and the bios has somehow broken support for non-uefi case via bios
> services.
>
> Well, I didn't expect that native usb drivers makes booting of windows
> impossible.
>

Well ... driver changes hardware state without BIOS being aware of it
so we try to play safe. If it possible to allow concurrent BIOS and
GRUB access, someone with better USB knowledge please chime in.

I understand.
 

> Thanks,
> Jan
>
> On Thu, Feb 11, 2016 at 10:24 AM Andrei Borzenkov <address@hidden>
> wrote:
>>
>> On Thu, Feb 11, 2016 at 12:04 PM, Jan Gregor <address@hidden> wrote:
>> > Hello,
>> >
>> >   my keyboard (microsoft natural 4000) doesn't work in boot managers
>>
>> Do you mean it also does not work in other boot managers, not only GRUB?
>>
>> > although it is functional in bios, windows, linux and uefi mode.
>> > Unfortunatelly my disk works in mbr mode so uefi is not option for me.
>> > The
>> > keyboard worked ok with old computer so I think the problem relates to
>> > my
>> > current motherboard (asus p9dws).
>> >
>> >  I use grub2 from fresh debian installation (jessie), version
>> > 2.02~beta2-22+deb8u1.
>> >
>> >  Without modifications, grub2 boots without problems debian and windows
>> > 10.
>> > Unfortunately due to unfuctional keyboard I have to externally change
>> > default option.
>> >
>> >  When I added following lines to start of grub.cfg, my keyboard works.
>> >     nativedisk
>> >     insmod usb
>> >     insmod usb_keyboard
>> >     insmod ehci
>> >
>> >  Unfortunatelly boot of windows 10 ends with following error message
>> >
>> >    A disk read error occured. Press Ctrl + Alt + Del
>> >
>> > I think the error can relate to usb support that forces grub to use
>> > nativedisk module. Can you recommend how to solve booting of windows 10
>> > in
>> > this case ?
>> >
>>
>> No, you cannot chainload Windows once you tainted system with native
>> USB drivers. But the real question is why keyboard does not work. GRUB
>> is using BIOS services to perform input/output and you say it works in
>> BIOS setup, correct? It sounds like BIOS stops USB support when it
>> boots something. Try playing with BIOS setup options, in particular
>> "Legacy USB Support"; according to documentation if it is disabled,
>> then "USB devices can be used only for the BIOS setup program".

reply via email to

[Prev in Thread] Current Thread [Next in Thread]