
uefi_call_wrapper()
-------------------
gnu-efi provides this macro thing as a workaround for older compilers that
don't support the right attributes to handle the fact that the EFI calling
conventions are different than the standard gcc ones.

If HAVE_USE_MS_ABI is defined (as the Makefile here does) and you have a
compiler that's not a fairly ancient, everything Just Works(tm) and the
code is much more readable.


Intel Visual BIOS (on NUC) and netboot
--------------------------------------
This will netboot EFI apps, provided you have a DHCP server which is
setup to give the BIOS the IP of a tftp server and a filename to grab
from there.

You must disable legacy boot for the EFI netboot option to appear.  If
you check the "keep retrying forever" option, when your app exits, the
BIOS will try to download it from the tftp server again, making for a
quick build/download/test cycle


Making tftpd work on Ubuntu with IPv4
-------------------------------------
sudo apt-get install tftpd-hpa

Optionally make it easy to copy files to the server without sudo:
sudo chown `who` /var/lib/tftpdboot 

Edit /etc/default/tftpd-hpa so it looks more like:
TFTP_USERNAME="tftp"
TFTP_DIRECTORY="/var/lib/tftpboot"
TFTP_ADDRESS=":69"
TFTP_OPTIONS="--secure -4 -v -v -v"

Removing the [::] and adding the -4 make it work reliably on IPv4 for me.
The several -v's make it chattier in syslog which is handy if you're not
sure the test machine is actually trying to grab files.

QEMU Tips
-------------------------------------
USB-ETH Adapters:
- For ASIX chipset usb adapters if you have permission issues copy the udev rules in scripts/ to /etc/udev/rules.d/

E1000 local networking bridge:
- You can create a network interface using the Linux tun/tap network device named “qemu” for the
  qemu-e1000 target. Qemu does not need to be run with any special privileges for this, but you need
  to create a persistent tun/tap device ahead of time (which does require you be root):

  sudo apt-get install uml-utilities
  sudo tunctl -u $USER -t qemu
  sudo ifconfig qemu up