.. Fixing annoying Gentoo error messages

Do you receive these errors?

No suitable mode found

or

Missing ... unicode.pcf

If so, follow these steps:

USE=truetype emerge grub

The truetype flag of grub is needed to get the grub2-mkfont executable. If you want this executable for every update of grub then you will need to add it to your /etc/portage/package.use permanently by adding the line:

sys-boot/grub truetype

Now we need the unifont package:

emerge unifont

And we use the unifont tools to convert the .hex file to bdf format:

hex2bdf /usr/share/unifont/unifont.hex > unifont.bdf

And convert .bdf to .pf2:

grub2-mkfont -o unicode.pf2 unifont.bdf

You need to copy the .pf2 file to a fonts folder in the grub prefix folder. The examples below use the usual prefix of /boot/grub:

mkdir /boot/grub/fonts
sudo mv unicode.pf2 /boot/grub/fonts

And create a /boot/grub/custom.cfg file containing:

insmod font

if loadfont ${prefix}/fonts/unicode.pf2
then
    insmod gfxterm
    set gfxmode=auto
    set gfxpayload=keep
    terminal_output gfxterm
fi

Creating a custom.cfg prevents the settings getting overwritten on a grub update. There is no need to regenerate anything.

Do you receive this error message?

drivers/rtc/hctosys.c: unable to open rtc device (rtc0)

Disable CONFIG_RTC_HCTOSYS in kernel using a graphical tool:

genkernel --splash --install --menuconfig all

Look for Device Drivers -> Real Time System Clock and disable it with spacebar. Or press / to search for CONFIG_RTC_HCTOSYS and it will tell you where that option is located in the tree. See here for explanation of what the RTC is used for, and whether or not you need it. Most people don't.