[PATCH 1/3] ARM: debug: use kconfig choice for selecting DEBUG_LL UART
Nicolas Pitre
nico at fluxnic.net
Thu Aug 18 00:06:25 EDT 2011
On Tue, 16 Aug 2011, Will Deacon wrote:
> 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.
>
> Cc: Linus Walleij <linus.walleij at stericsson.com>
> Signed-off-by: Will Deacon <will.deacon at arm.com>
Acked-by: Nicolas Pitre <nicolas.pitre at linaro.org>
(ditto for the other 2 patches)
> ---
> arch/arm/Kconfig.debug | 41 ++++++++++++++++++++++++-----------------
> 1 files changed, 24 insertions(+), 17 deletions(-)
>
> diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
> index 81cbe40..11604c9 100644
> --- a/arch/arm/Kconfig.debug
> +++ b/arch/arm/Kconfig.debug
> @@ -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"
> --
> 1.7.0.4
>
>
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