blob: 5837a102a6dcd6b0728b76f02c7b1630b29f8874 [file] [log] [blame]
config X86
select 64BIT
def_bool y
config X86_64
def_bool 64BIT
menu "x86 Options"
config PCI_VERBOSE
bool "Verbose PCI Output"
default n
help
Will print out extra information related to PCI.
config NOFASTCALL_FSBASE
depends on X86_64
bool "Disable fastcall to set FS base"
default n
help
Disable the fast path syscall to set FS base. If your hardware
allows setting FS base from userspace, you can say y to disable the
fastcall for a slight improvement for all syscalls. If unsure, say
n.
endmenu
menu "x86 Hacks"
config LOUSY_LAPIC_TIMER
bool "Lousy Local APIC Timer"
default n
help
This turns our one-shot APIC timer into a periodic timer. If your
system seems to lock up until you hit the keyboard, say 'Y' here and
report the results.
Qemu without KVM had issues firing a one-shot LAPIC timer (the timer
IRQ would only go off when some other IRQ fired), but it worked with
a periodic tick. Since we aggressively disarm the timer, this config
shouldn't be a performance hit.
config NOMTRRS
bool "Disable MTRRs"
default y
help
Old debug option from when we were having issues with MTRRs. If your
machine won't boot, try turning this on.
config KB_CORE0_ONLY
bool "Keyboard from core0 only"
default n
help
Say 'n' unless you are using a buggy x86 machine that can't handle
polling the keyboard PIO from cores other than core 0.
config X86_DISABLE_KEYBOARD
bool "Disable Keyboard"
default n
help
x86 machines with a legacy USB keyboard often implement the USB stack
in SMM mode. When doing anything with the keyboard, including
polling the keyboard from the kernel monitor, SMM mode can
dramatically interfere with other cores (like a 10-15x performance
impact on some benchmarks).
Say 'y' if you have such a machine and do not need the keyboard.
config ENABLE_LEGACY_USB
bool "Enable Legacy USB"
default n
help
Say 'y' if you want to use a USB keyboard. Given that we do not have
a USB stack, disabling legacy USB means USB keyboards will not work.
We disable legacy USB by default, since our primary console
communication is serial, and legacy USB support results in SMM
interference that affects all cores.
endmenu