Apollo Lake GPIO driver with Coreboot/U-Boot

[Wolfgang Wallner]

Hello Simon, Bin, all,

I have an Apollo Lake based device, where U-Boot is booted as a Coreboot
payload. I would like to utilize the Apollo Lake GPIO driver
(drivers/gpio/intel_gpio.c), but I struggle with the dependencies.

For my use case, I face 2 obstacles:

  1) Some required drivers are not built

    The Apollo Lake GPIO driver requires the P2SB and ITSS drivers, but those
    are located in arch/x86/cpu/apollolake. Drivers in this directory are not
    included in my build as it builds for Coreboot, not for Apollo Lake.

  2) Some header files are not found

    The header files gpio.h and itss.h are located in
    arch/x86/include/asm/arch-apollolake, but as I build for Coreboot the
    symlink arch/x86/include/asm/arch points to arch-coreboot instead of
    arch-apollolake, so those header files are not found.

Does anyone have recommendations on how to solve those issues?
Would it be possible to move the drivers for P2SB and ITSS out of
arch/x86/cpu/apollolake to the generic drivers/ directory?

regards, Wolfgang

PS: Thanks Simon for providing the initial support for Apollo Lake!