This is a very simple method for code running in an emulator, or under
the supervision of a debugger, to use I/O facilities on the controlling
host.
Tested with OpenOCD, and ARM's Fast Models.
Details on semihosting can be found in chapter 8 of
DUI0203I_rvct_developer_guide.pdf from ARM Ltd.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
we will select now the DBGU used by the soc at Kconfig level
For the DEBUG_LL and early_printk this will allow to select which DBGU to use
this will also allow to select them when multiple SOC are enabled
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Add support for DEBUG_LL on the 8660 and 8960 development boards.
While we're here cleanup the uncompress.h code a bit. Avoid
the use of readl/writel as those are Linux specific APIs that
aren't guaranteed to work in the decompressor.
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: David Brown <davidb@codeaurora.org>
Now that DEBUG_LL is a choice we can move MSM's homegrown choice
menu to DEBUG_LL.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: David Brown <davidb@codeaurora.org>
* 'next/soc' of git://git.linaro.org/people/arnd/arm-soc: (21 commits)
MAINTAINERS: add ARM/FREESCALE IMX6 entry
arm/imx: merge i.MX3 and i.MX6
arm/imx6q: add suspend/resume support
arm/imx6q: add device tree machine support
arm/imx6q: add smp and cpu hotplug support
arm/imx6q: add core drivers clock, gpc, mmdc and src
arm/imx: add gic_handle_irq function
arm/imx6q: add core definitions and low-level debug uart
arm/imx6q: add device tree source
ARM: highbank: add suspend support
ARM: highbank: Add cpu hotplug support
ARM: highbank: add SMP support
MAINTAINERS: add Calxeda Highbank ARM platform
ARM: add Highbank core platform support
ARM: highbank: add devicetree source
ARM: l2x0: add empty l2x0_of_init
picoxcell: add a definition of VMALLOC_END
picoxcell: remove custom ioremap implementation
picoxcell: add the DTS for the PC7302 board
picoxcell: add the DTS for pc3x2 and pc3x3 devices
...
Fix up trivial conflicts in arch/arm/Kconfig, and some more header file
conflicts in arch/arm/mach-omap2/board-generic.c (as per an ealier merge
by Arnd).
* 'next/cross-platform' of git://git.linaro.org/people/arnd/arm-soc:
arm/imx: use Kconfig choice for low-level debug UART selection
ARM: realview: use Kconfig choice for debug UART selection
ARM: plat-samsung: use Kconfig choice for debug UART selection
ARM: versatile: convert logical CPU numbers to physical numbers
ARM: ux500: convert logical CPU numbers to physical numbers
ARM: shmobile: convert logical CPU numbers to physical numbers
ARM: msm: convert logical CPU numbers to physical numbers
ARM: exynos4: convert logical CPU numbers to physical numbers
Fix up trivial conflict (config DEBUG_S3C_UART move/split vs addition of
ARM_KPROBES_TEST option) in arch/arm/Kconfig.debug
Now that the DEBUG_LL UART can be selected by a Kconfig choice,
simplify the #ifdefery in debug-macro.S and add entries to the
top-level Kconfig.debug instead.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Now that the DEBUG_LL UART can be selected by a Kconfig choice, simplify
the #ifdefery in debug-macro.S and add entries to the top-level
Kconfig.debug instead.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Now that the DEBUG_LL UART can be selected by a Kconfig choice, convert
the Samsung UART selection to use a set of bools rather than an int.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Defaulting to DEBUG_ICEDCC will cause systems to hang during boot unless
a hardware debugger is listening to the debug comms. channel.
This patch adds a dummy UART option as the default DEBUG_LL choice which
requires the platform to do the right thing.
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
DEBUG_ICEDCC support is just another DEBUG_LL choice and
selecting it along with other DEBUG_LL options doesn't make
much sense. Put it into the DEBUG_LL choice to avoid confusion.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM patch 7072/1 (debug: use kconfig choice for selecting
DEBUG_LL UART) didn't notice that the Kconfigs relied on being
unselected to configure a different serial port. Since there is
no NONE option in a choice menu, explicitly add the other option
so that both serial ports can be selected.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Enabled DEBUG_LL hardcodes the UART address into the kernel and results
in a non-portable kernel image. Since this option is only intended for
use when debugging early boot failures, supporting multiple platforms
in such a configuration is not the intended use-case.
This patch documents this limitation in the DEBUG_LL Kconfig help text,
so that users are aware of the portability restrictions that are associated
with enabling low-level debugging support.
Reported-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The CONFIG_ARM_AMBA symbol is selected by the platforms that support
AMBA, and the other platforms (e.g. orion) might not be able to
build that code at all when they do not support the clk API.
Instead, make sure that OC_ETM is only built on platforms that
do support the amba subsystem already.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Nicolas Pitre
Arnd Bergmann
Jean-Christophe PLAGNIOL-VILLARD
Stephen Boyd
Linus Torvalds
Shawn Guo
Rob Herring
Russell King
Will Deacon
Jon Medhurst