Coreboot test cases.

tested combos:

1. coreboot+libgfxinit+seabios: all outputs are on serialport,no graphics, boots mbr grub ok but from there on, not consistant with system loading, like not booing, failed to load the kernel, writing outside hd0.

2. coreboot+GOP+seabios: triggers the Graphics only during boot device selection and then goes away,the graphics, rest outputs are on serialport again, boots mbr grub ok but from there on, not consistant with system loading, like not booing, failed to load the kernel, writing outside hd0.

3. coreboot+libgfxinit+tcore+coreboot_payload: no GRUB

4. coreboot+libgfxinit+tcore+uefi_payload: (need to try with Graphics card, no DISPLAY)

5. coreboot+libgfxinit+tcore_debug+coreboot_payload: reveals a lot which also includes USB initializing issue, (need to try with Graphics card, may be GOP is not necessary for the Graphics card), no GRUB

6. coreboot+libgfxinit+tcore_debug+uefi_payload: tcore_debug and uefi_payload does not go along no matter if switched to GOP from libgfxinit and also including onboard_vga (So not usable)

7. coreboot+GOP+tcore+coreboot_payload:

8. coreboot+GOP+tcore+uefi_payload: last tested, logs available, CLI boot with nomodeset was successful, No DISPLAY with builtin Graphics. No display even with the Graphics Card (Card was attached later).

9. coreboot+GOP+tcore_debug+coreboot_payload: (need to try with Graphics card, may be GOP is not necessary for the Graphics card)


The onboard VGA didn't help much on any case:

10. coreboot+libgfxinit+tcore+uefi_payload+onboard_vga: on goin now (16-02-2020 10.47 PM), did not activated the display even after the booting into CLI mode using the serial port.

11. coreboot+GOP+tcore+uefi_payload+onboard_vga:

Summery (so far) : tcore+coreboot_payload does not load the GRUB, only UEFI_payload loads the GRUB in tcore's case. And tcore_debug and uefi_payload does not go along but tcore_debug always triggers the Display with coreboot_logo but stays there, nothing happens afterwards. Tried coreboot with single MBR partitioned HDD along with SeaBIOS results in frequent not booing, failed to load the kernel, writing outside hd0 after if FspSiliconInit succeeds, most of the time itdoesn't (in both MBR and UEFI case) and also with GPT partitioned HDD along with tcore, from GRUB tcore handles the process better afterwards as it is mentioned in Intel FSP manual, FSP works better with UEFI.

kernel parameters used:
acpi=off iomem=relaxed nomodeset random.trust_cpu=on initcall_debug console=tty0 console=ttyS0,115200 earlyprintk=ttyS0,115200

with acpi=off for stock uefi bios, the system boots but on coreboot it keeps in kernel loading state with no further logs,

but nomodeset (ofcourse without acpi=off) allowed both Parabola and Ubuntu to boot into CLI mode accessible only from the serial port, still the main display is turned off on both system's case. Turns out in case of stock uefi bios, nomodeset parameter boots into CLI mode obviously with the main DISPLAY activated from the beginning but can not run the Xorg server.