efi: efi-stub: notify on DTB absence
efi: efi-stub: notify on DTB absence

In the absence of a DTB configuration table, the EFI stub will happily
continue attempting to boot a kernel, despite the fact that this kernel
may not function without a description of the hardware. In this case, as
with a typo'd "dtb=" option (e.g. "dbt=") or many other possible
failures, the only output seen by the user will be the rather terse
output from the EFI stub:

EFI stub: Booting Linux Kernel...

To aid those attempting to debug such failures, this patch adds a notice
when no DTB is found, making the output more helpful:

EFI stub: Booting Linux Kernel...
EFI stub: Generating empty DTB

Additionally, a positive acknowledgement is added when a user-specified
DTB is in use:

EFI stub: Booting Linux Kernel...
EFI stub: Using DTB from command line

Similarly, a positive acknowledgement is added when a DTB from a
configuration table is in use:

EFI stub: Booting Linux Kernel...
EFI stub: Using DTB from configuration table

Signed-off-by: Mark Rutland <1db9dd262beaa64f35756dd39531d9747b7778bb@arm.com>
Acked-by: Leif Lindholm <a613079f0455438b29e28a9c5b9eb3779a81a33a@linaro.org>
Acked-by: Ard Biesheuvel <66d3c5fdaeea7ff1f996ad04f2c45e08ab38e2f5@linaro.org>
Acked-by: Roy Franz <a58e234ead0397b00b518065b0b5eff3dd8aab1a@linaro.org>
Acked-by: Matt Fleming <b02f0790d66a0f0a6b369873bf6df37420fbe5dd@intel.com>
Signed-off-by: Ard Biesheuvel <66d3c5fdaeea7ff1f996ad04f2c45e08ab38e2f5@linaro.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs