[efi] Add options to set console to native monitor resolution

[jdieter]

Currently, there's no way to change the screen mode to the optimum mode for the monitor. This patch adds two options to rectify that. The first option, '-a' or '--auto', chooses the first EFI graphics mode, which on most systems is the native mode.

However, on some systems the first mode is the mode the BIOS interface is designed to use, and may not actually be the native resolution of the monitor (i.e. the monitor resolution is 1600x900, while the first mode is 1280x1024). So the second option, '-w' or '--max-width', chooses the widest EFI graphics mode, on the assumption that that is the native monitor resolution.

In this patch, -w takes precedence over -a and both override the sizes given by -x, -y and -p.

[ipxe-devel]

On 12/03/16 20:48, Jonathan Dieter wrote:

Currently, there's no way to change the screen mode to the optimum mode
for the monitor. This patch adds two options to rectify that. The first
option, '-a' or '--auto', chooses the first EFI graphics mode, which on
most systems is the native mode.

However, on some systems the first mode is the mode the BIOS interface
is designed to use, and may not actually be the native resolution of the
monitor (i.e. the monitor resolution is 1600x900, while the first mode
is 1280x1024). So the second option, '-w' or '--max-width', chooses the
widest EFI graphics mode, on the assumption that that is the native
monitor resolution.

Both of those seem like very crude heuristics which are likely to be
true only for certain systems and only when certain monitors are attached.

Can you find a better approach?

Michael

[jdieter]

Yeah, just did some research and apparently we can get the EDID using EFI. I'm thinking that might be slightly more robust. It's getting late, so I'll look into that tomorrow.

[jdieter]

And, yes, I do feel a bit like an idiot. ;)