ARM64 EFI runtime

ARM64 EFI runtime

[Brijesh Singh]

Hi All,

I noticed that DOM0 kernel fails to get time via RTC device on AMD ARM64 (Seattle) platform. On this platform Linux uses rtc-efi driver to get the time through EFI runtime services, and I know for sure that driver works well outside the Xen environment. It seems that devicetree passed to DOM0 through Xen does not contain UEFI system table information hence DOM0 fails to probe rtc-efi platform driver. I see the below message in DOM0 dmesg log

[    0.000000] bootconsole [uart0] enabled
[    0.000000] efi: Getting EFI parameters from FDT:
[    0.000000] efi: UEFI not found.
[    0.000000] cma: Reserved 16 MiB at 0x00000083df000000


Looking at Xen's common/efi/runtime.c indicates that EFI runtime services are not yet supported on ARM platform, is anyone working on it? 

Thanks
Brijesh

Re: ARM64 EFI runtime

[Stefano Stabellini]

Hi Brijesh,

EFI runtime services are not currently exported to Dom0. They are still
a work in progress.

Regards,

Stefano

On Mon, 12 Oct 2015, Brijesh Singh wrote:
> Hi All,
> 
> I noticed that DOM0 kernel fails to get time via RTC device on AMD ARM64 (Seattle) platform. On this platform Linux uses rtc-efi driver to get the time through EFI runtime services, and I know for sure that driver works well outside the Xen environment. It seems that devicetree passed to DOM0 through Xen does not contain UEFI system table information hence DOM0 fails to probe rtc-efi platform driver. I see the below message in DOM0 dmesg log
> 
> [    0.000000] bootconsole [uart0] enabled
> [    0.000000] efi: Getting EFI parameters from FDT:
> [    0.000000] efi: UEFI not found.
> [    0.000000] cma: Reserved 16 MiB at 0x00000083df000000
> 
> 
> Looking at Xen's common/efi/runtime.c indicates that EFI runtime services are not yet supported on ARM platform, is anyone working on it? 
> 
> Thanks
> Brijesh
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel
> 

Re: ARM64 EFI runtime

[Brijesh Singh]

Thanks for update Stefano,

If you have some sample code on private git then please point me at it. I should be able to help on both development and testing on Seattle  platform. 

-Brijesh

On 10/13/2015 04:57 AM, Stefano Stabellini wrote:
> Hi Brijesh,
> 
> EFI runtime services are not currently exported to Dom0. They are still
> a work in progress.
> 
> Regards,
> 
> Stefano
> 
> On Mon, 12 Oct 2015, Brijesh Singh wrote:
>> Hi All,
>>
>> I noticed that DOM0 kernel fails to get time via RTC device on AMD ARM64 (Seattle) platform. On this platform Linux uses rtc-efi driver to get the time through EFI runtime services, and I know for sure that driver works well outside the Xen environment. It seems that devicetree passed to DOM0 through Xen does not contain UEFI system table information hence DOM0 fails to probe rtc-efi platform driver. I see the below message in DOM0 dmesg log
>>
>> [    0.000000] bootconsole [uart0] enabled
>> [    0.000000] efi: Getting EFI parameters from FDT:
>> [    0.000000] efi: UEFI not found.
>> [    0.000000] cma: Reserved 16 MiB at 0x00000083df000000
>>
>>
>> Looking at Xen's common/efi/runtime.c indicates that EFI runtime services are not yet supported on ARM platform, is anyone working on it? 
>>
>> Thanks
>> Brijesh
>>
>> _______________________________________________
>> Xen-devel mailing list
>> Xen-devel@lists.xen.org
>> http://lists.xen.org/xen-devel
>>

Re: ARM64 EFI runtime

[Stefano Stabellini]

Hi Brijesh,

passing EFI tables to dom0 is still under work by Shannon, see:
http://marc.info/?l=xen-devel&m=144321258920213. For now you could
simply reuse the existing linux uefi device tree nodes, see
Documentation/arm/uefi.txt and the existing acpi patch series for Xen,
which also introduces passing efi tables to dom0:
http://marc.info/?l=xen-devel&m=143189314630953.

Once dom0 knows about efi, then it is just a matter of enabling the
existing PV runtime services on arm64, see drivers/xen/efi.c.


On Tue, 13 Oct 2015, Brijesh Singh wrote:
> Thanks for update Stefano,
> 
> If you have some sample code on private git then please point me at it. I should be able to help on both development and testing on Seattle  platform. 
> 
> -Brijesh
> 
> On 10/13/2015 04:57 AM, Stefano Stabellini wrote:
> > Hi Brijesh,
> > 
> > EFI runtime services are not currently exported to Dom0. They are still
> > a work in progress.
> > 
> > Regards,
> > 
> > Stefano
> > 
> > On Mon, 12 Oct 2015, Brijesh Singh wrote:
> >> Hi All,
> >>
> >> I noticed that DOM0 kernel fails to get time via RTC device on AMD ARM64 (Seattle) platform. On this platform Linux uses rtc-efi driver to get the time through EFI runtime services, and I know for sure that driver works well outside the Xen environment. It seems that devicetree passed to DOM0 through Xen does not contain UEFI system table information hence DOM0 fails to probe rtc-efi platform driver. I see the below message in DOM0 dmesg log
> >>
> >> [    0.000000] bootconsole [uart0] enabled
> >> [    0.000000] efi: Getting EFI parameters from FDT:
> >> [    0.000000] efi: UEFI not found.
> >> [    0.000000] cma: Reserved 16 MiB at 0x00000083df000000
> >>
> >>
> >> Looking at Xen's common/efi/runtime.c indicates that EFI runtime services are not yet supported on ARM platform, is anyone working on it? 
> >>
> >> Thanks
> >> Brijesh
> >>
> >> _______________________________________________
> >> Xen-devel mailing list
> >> Xen-devel@lists.xen.org
> >> http://lists.xen.org/xen-devel
> >>
> 

Re: ARM64 EFI runtime

[Julien Grall]

On 13/10/15 15:55, Stefano Stabellini wrote:
> Hi Brijesh,
> 
> passing EFI tables to dom0 is still under work by Shannon, see:
> http://marc.info/?l=xen-devel&m=144321258920213. For now you could
> simply reuse the existing linux uefi device tree nodes, see
> Documentation/arm/uefi.txt and the existing acpi patch series for Xen,
> which also introduces passing efi tables to dom0:
> http://marc.info/?l=xen-devel&m=143189314630953.
> 
> Once dom0 knows about efi, then it is just a matter of enabling the
> existing PV runtime services on arm64, see drivers/xen/efi.c.

That's not true. There is work to do in Xen in order to support efi
runtime. The hypercall to call runtime services (XENPF_efi_runtime_call)
is not plumbed and most of the code in common/efi/runtime.c is not built.

Regards,

-- 
Julien Grall