base-config: add FRAMEBUFFER_CONSOLE

[marc-hb]

When graphics fail, a blank screen is not useful.

Even when graphics work, without a framebuffer console chvt still
works but it is "blind" / with a frozen GUI instead! Incredibly
confusing. Linux distributions expect this.

Also useful in case of hangs like
thesofproject/linux#3387: text consoles
are always more responsive and they may even have some logs

Signed-off-by: Marc Herbert [email protected]

[lgirdwood]

@plbossart fyi

[marc-hb]

@plbossart pointed me at https://fedoraproject.org/wiki/Changes/ReplaceFbdevDrivers... trying to find time and have a look.

[marc-hb]

I reverted this change locally and made a naive attempt where I enabled CONFIG_SYSFB_SIMPLEFB=y instead as described at https://fedoraproject.org/wiki/Changes/ReplaceFbdevDrivers. It did not work on my UP2 with Ubuntu 20, the text consoles still work "blindly" while displaying a frozen GUI.

Unless someone (@kv2019i ?) can explain the following jargon to me I'm going to leave this as it is now.

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/firmware/Kconfig

config SYSFB_SIMPLEFB
	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
	depends on SYSFB
	help
	  Firmwares often provide initial graphics framebuffers so the BIOS,
	  bootloader or kernel can show basic video-output during boot for
	  user-guidance and debugging. Historically, x86 used the VESA BIOS
	  Extensions and EFI-framebuffers for this, which are mostly limited
	  to x86 BIOS or EFI systems.
	  This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
	  framebuffers so the new generic system-framebuffer drivers can be
	  used instead. If the framebuffer is not compatible with the generic
	  modes, it is advertised as fallback platform framebuffer so legacy
	  drivers like efifb, vesafb and uvesafb can pick it up.
	  If this option is not selected, all system framebuffers are always
	  marked as fallback platform framebuffers as usual.

	  Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
	  not be able to pick up generic system framebuffers if this option
	  is selected. You are highly encouraged to enable simplefb as
	  replacement if you select this option. simplefb can correctly deal
	  with generic system framebuffers. But you should still keep vesafb
	  and others enabled as fallback if a system framebuffer is
	  incompatible with simplefb.

	  If unsure, say Y.