Commit 17916b28 authored by Will Deacon's avatar Will Deacon Committed by Russell King
Browse files

ARM: 7072/1: debug: use kconfig choice for selecting DEBUG_LL UART 



Enabling CONFIG_DEBUG_LL (which is required for earlyprintk) hardwires
the debug UART address into the kernel, so that we can print before the
platform is initialised.

If the user inadvertently selects multiple platforms with DEBUG_LL
enabled, the UART address may not be correct and will likely cause the
kernel to hang in the very early stages of boot.

This patch, based on a skeleton from Russell, uses a Kconfig choice for
selecting the DEBUG_LL UART, therefore allowing the user to make a
choice about the supported platform when DEBUG_LL is enabled.

Acked-by: default avatarNicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent d0a77454

arch/arm/Kconfig.debug

+24 −17
Original line number Diff line number Diff line
@@ -72,6 +72,30 @@ config DEBUG_LL 
	  in the kernel.  This is helpful if you are debugging code that

	  executes before the console is initialized.



choice

	prompt "Kernel low-level debugging port"

	depends on DEBUG_LL



	config DEBUG_DC21285_PORT

		bool "Kernel low-level debugging messages via footbridge serial port"

		depends on FOOTBRIDGE

		help

		  Say Y here if you want the debug print routines to direct

		  their output to the serial port in the DC21285 (Footbridge).

		  Saying N will cause the debug messages to appear on the first

		  16550 serial port.



	config DEBUG_CLPS711X_UART2

		bool "Kernel low-level debugging messages via UART2"

		depends on ARCH_CLPS711X

		help

		  Say Y here if you want the debug print routines to direct

		  their output to the second serial port on these devices.

		  Saying N will cause the debug messages to appear on the first

		  serial port.



endchoice



config EARLY_PRINTK

	bool "Early printk"

	depends on DEBUG_LL
@@ -100,23 +124,6 @@ config OC_ETM 
	  buffer driver that will allow you to collect traces of the

	  kernel code.



config DEBUG_DC21285_PORT

	bool "Kernel low-level debugging messages via footbridge serial port"

	depends on DEBUG_LL && FOOTBRIDGE

	help

	  Say Y here if you want the debug print routines to direct their

	  output to the serial port in the DC21285 (Footbridge). Saying N

	  will cause the debug messages to appear on the first 16550

	  serial port.



config DEBUG_CLPS711X_UART2

	bool "Kernel low-level debugging messages via UART2"

	depends on DEBUG_LL && ARCH_CLPS711X

	help

	  Say Y here if you want the debug print routines to direct their

	  output to the second serial port on these devices.  Saying N will

	  cause the debug messages to appear on the first serial port.



config DEBUG_S3C_UART

	depends on PLAT_SAMSUNG

	int "S3C UART to use for low-level debug"

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