[U-Boot] [PATCH] efi_loader: Add network access support

[Alexander Graf]

> Am 03.05.2016 um 01:11 schrieb Peter Robinson <pbrobinson at gmail.com>:
> 
>> On Mon, May 2, 2016 at 10:43 PM, Alexander Graf <agraf at suse.de> wrote:
>> We can now successfully boot EFI applications from disk, but users
>> may want to also run them from a PXE setup.
>> 
>> This patch implements rudimentary network support, allowing a payload
>> to send and receive network packets.
>> 
>> With this patch, I was able to successfully run grub2 with network
>> access inside of QEMU's -M xlnx-ep108.
>> 
>> Signed-off-by: Alexander Graf <agraf at suse.de>
>> 
>> ---
>> 
>> What's missing? We need to verify that this patch works on real hardware.
>> Also actual pxe integration is missing. The bootp client would have to send
>> a different identifier to say "I'm EFI" and the execution code afterwards
>> would need to use bootefi. I guess we could switch to such a mode through
>> a variable?
>> 
>> I'm also not quite sure where we should pull the device tree from in the
>> pxe case. It really only makes sense when the device tree gets bundled with
>> U-Boot.
> 
> Not necessarily, in the distro boot case for ARMv7 we're pulling the
> dtb from tftp along with the kernel and initrd, there should already
> be examples of this that work fine in u-boot and we use it as part of
> automated device testing in Fedora already.

Sorry, with "makes sense" I meant that I can't think of a standardized way to know the dtb file name. I guess we could use logic similar to the current disk boot path, which loops through a number of directories plus $fdtfile to search for a matching dtb...

Either way, pxe integration is separate from network access and I wanted to get this into people's hands early to get feedback before the next merge window ;).


Alex