arm: mvebu: add another earlyprintk Kconfig option
In order to support both old and new bootloaders, we add a new Kconfig
option for the earlyprintk UART selection. The existing option allows
to work with old bootloaders (that keep the internal registers mapped
at 0xd0000000), while the newly introduced option allows to work with
new bootloaders (that remap the internal registers at 0xf1000000).
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 1d41908..e6a6ab1 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -303,12 +303,37 @@
their output to the serial port on MSM 8960 devices.
config DEBUG_MVEBU_UART
- bool "Kernel low-level debugging messages via MVEBU UART"
+ bool "Kernel low-level debugging messages via MVEBU UART (old bootloaders)"
depends on ARCH_MVEBU
help
Say Y here if you want kernel low-level debugging support
on MVEBU based platforms.
+ This option should be used with the old bootloaders
+ that left the internal registers mapped at
+ 0xd0000000. As of today, this is the case on
+ platforms such as the Globalscale Mirabox or the
+ Plathome OpenBlocks AX3, when using the original
+ bootloader.
+
+ If the wrong DEBUG_MVEBU_UART* option is selected,
+ when u-boot hands over to the kernel, the system
+ silently crashes, with no serial output at all.
+
+ config DEBUG_MVEBU_UART_ALTERNATE
+ bool "Kernel low-level debugging messages via MVEBU UART (new bootloaders)"
+ depends on ARCH_MVEBU
+ help
+ Say Y here if you want kernel low-level debugging support
+ on MVEBU based platforms.
+
+ This option should be used with the new bootloaders
+ that remap the internal registers at 0xf1000000.
+
+ If the wrong DEBUG_MVEBU_UART* option is selected,
+ when u-boot hands over to the kernel, the system
+ silently crashes, with no serial output at all.
+
config DEBUG_NOMADIK_UART
bool "Kernel low-level debugging messages via NOMADIK UART"
depends on ARCH_NOMADIK
@@ -632,7 +657,8 @@
DEBUG_IMX51_UART || \
DEBUG_IMX53_UART ||\
DEBUG_IMX6Q_UART
- default "debug/mvebu.S" if DEBUG_MVEBU_UART
+ default "debug/mvebu.S" if DEBUG_MVEBU_UART || \
+ DEBUG_MVEBU_UART_ALTERNATE
default "debug/mxs.S" if DEBUG_IMX23_UART || DEBUG_IMX28_UART
default "debug/nomadik.S" if DEBUG_NOMADIK_UART
default "debug/omap2plus.S" if DEBUG_OMAP2PLUS_UART