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CONFIG_X86_VERY_EARLY_CONSOLE

Support very early boot printk

Type: bool

Help

Non-emulated X86 devices often require special hardware to attach
a debugger, which may not be easily available. This option adds a
very minimal serial driver which gets initialized at the very
beginning of z_cstart(), via arch_kernel_init(). This driver enables
printk to emit messages to the 16550 UART port 0 instance in device
tree. This mini-driver assumes I/O to the UART is done via ports.

Direct dependencies

SOC_LAKEMONT || (PRINTK && X86)

(Includes any dependencies from ifs and menus.)

Defaults

  • n

  • y

Kconfig definitions

At soc/x86/lakemont/Kconfig.defconfig:15

Included via Kconfig:8Kconfig.zephyr:27

Menu path: (Top)

config X86_VERY_EARLY_CONSOLE
    bool
    default n
    depends on SOC_LAKEMONT

At arch/x86/Kconfig:326

Included via Kconfig:8Kconfig.zephyr:39arch/Kconfig:12

Menu path: (Top) → X86 Architecture Options

config X86_VERY_EARLY_CONSOLE
    bool "Support very early boot printk"
    default y
    depends on PRINTK && X86
    help
      Non-emulated X86 devices often require special hardware to attach
      a debugger, which may not be easily available. This option adds a
      very minimal serial driver which gets initialized at the very
      beginning of z_cstart(), via arch_kernel_init(). This driver enables
      printk to emit messages to the 16550 UART port 0 instance in device
      tree. This mini-driver assumes I/O to the UART is done via ports.

(The ‘depends on’ condition includes propagated dependencies from ifs and menus.)